Pancreatic adenocarcinoma remains one of the most aggressive and difficult-to-treat solid tumor malignancies, with a high mortality-to-incidence ratio. Globally, pancreatic cancer ranks 12th in terms of incidence but sixth for mortality signifying its aggressive behavior and limited treatment options. While the mortality rates for many other solid tumors have substantially improved over the past few decades, temporal trends in pancreatic cancer mortality rates are quite sobering. In the United States, from 2000 to 2020, the mortality rates from pancreatic cancer have increased, whereas at the same time, mortality rates from other cancers, such as lung, colorectal, or kidney, have fallen appreciably. Is this for lack of treatment innovation? How do we improve survival for patients with pancreatic cancer? In this chapter, we discuss the recent advances and future directions with targeted therapies and immunotherapies in the treatment of pancreatic cancer, and provide the reasons for both optimism and caution for the future of systemic treatment of pancreatic cancer.

Early recognition and characterization of soft tissue tumors is important for proper fetal and maternal care. Here, we present sonographic, fetal and postnatal MRI, and pathological findings of a rare case of congenital NTRK-rearranged malignant spindle cell sarcoma with TPM3-NTRK1 fusion in a male fetus.

Larotrectinib is the first-in-class, highly selective TRK inhibitor with demonstrated efficacy in various TRK fusion solid tumours. We report the efficacy and safety of larotrectinib in patients with TRK fusion gastrointestinal (GI) cancer.

Patients with TRK fusion GI cancer from NAVIGATE (NCT02576431) were included. Response was independent review committee (IRC)-assessed per RECIST v1.1.

As of July 2023, 44 patients were enrolled. Tumour types included colorectal (CRC; n = 26), pancreatic (n = 7), cholangiocarcinoma (n = 4), gastric (n = 3), and one each of appendiceal, duodenal, oesophageal and hepatic cancers. Of the 26 patients with CRC, 16 (62 %) had known microsatellite instability-high (MSI-H) status. For the 43 IRC-eligible patients, overall response rate was 28 % (95 % confidence interval [CI] 15-44) for all patients and 44 % (95 % CI 24-65) for those with CRC. In patients overall and in those with CRC, median duration of response was 27 months (95 % CI 6-not estimable [NE]) and 27 months (95 % CI 6-NE), median progression-free survival was 6 months (95 % CI 5-9) and 7 months (95 % CI 6-NE), and median overall survival was 13 months (95 % CI 7-29) and 29 months (95 % CI 7-NE), respectively. Grade 3/4 treatment-related adverse events (TRAEs) occurred in seven (16 %) patients. There were no deaths due to TRAEs.

Larotrectinib demonstrated long durability, extended survival and manageable safety in patients with TRK fusion GI cancer, including those with MSI-H CRC. This supports the wider adoption of next-generation sequencing testing for NTRK gene fusions in patients with GI cancer.

Entrectinib, a central nervous system (CNS)-penetrant TRK/ROS1 inhibitor, has demonstrated clinical activity in children with NTRK1/2/3 or ROS1 fusion-positive extracranial solid and CNS tumours. We present integrated data of entrectinib in children with NTRK or ROS1 fusion-positive tumours from the STARTRK-NG, TAPISTRY, and STARTRK-2 trials.

Efficacy analyses were undertaken on TRK/ROS1 inhibitor-naïve patients aged <18 years with metastatic/locally advanced NTRK1/2/3 or ROS1 fusion-positive extracranial solid or CNS tumours who received ≥1 entrectinib dose and had ≥6 months of follow-up from enrolment. Tumour responses were confirmed by blinded independent central review (BICR) per RECIST v1.1/RANO criteria.

BICR-assessed confirmed objective response rate (cORR). Key secondary endpoints: duration of response (DoR); time to response (TtR); safety.

As of 16 July 2023, out of 91 safety-evaluable patients, 64 (NTRK: n=44; ROS1: n=20) were efficacy evaluable. In the NTRK and ROS1 subgroups, respectively, median age was 4.0 years and 7.5 years; median survival follow-up was 24.2 months and 27.6 months. cORR was 72.7 % (NTRK, 95 % confidence interval [CI]: 57.2-85.0) and 65.0 % (ROS1, 95 % CI: 40.8-84.6). Median DoR was not reached (NTRK, 95 % CI: 25.4-not evaluable [NE]); ROS1, 95 % CI: 16.2-NE); median TtR was 1.9 months in both subgroups. The most frequently reported treatment-related adverse events included weight gain (35.2 %) and anaemia (31.9 %).

Integrated data from three trials confirm entrectinib induces rapid and durable responses in children with NTRK or ROS1 fusion-positive tumours. The increased duration of safety monitoring does not demonstrate new or cumulative toxicity. Registered clinical trials: STARTRK-NG: NCT02650401; TAPISTRY: NCT04589845; STARTRK-2: NCT02568267.

Liposomal irinotecan + fluorouracil/leucovorin (nal-IRI + 5FU/LV) is commonly used as a second- or later-line treatment for pancreatic ductal adenocarcinoma (PDAC) and offers survival benefits. However, its efficacy and safety in patients previously treated with FOLFIRINOX, which includes irinotecan, remain unclear. We evaluated the efficacy and safety of nal-IRI + 5FU/LV in patients with unresectable PDAC who received previous FOLFIRINOX therapy and those who did not.

This retrospective observational study included 42 patients with PDAC who were treated with nal-IRI + 5FU/LV (October 2020-November 2023). Patients were grouped based on prior FOLFIRINOX treatment.

The progression-free survival (PFS) in patients who previously received modified FOLFIRINOX (mFFX) therapy was shorter than that in patients who did not (2.5 vs. 3.5 months, P = 0.07). When patients with greater than- and less than the cut-off value of irinotecan-free interval (IFI) were classified into the long and short IFI groups, respectively, PFS was significantly longer in the long-IFI group than that in the short IFI group (4.0 vs. 2.1 months, P = 0.01). Moreover, the C-reactive protein/albumin ratio (CAR) was also a significant predictor of PFS (P = 0.03). Furthermore, both factors were found to be independent factors influencing PFS in the univariate Cox regression analysis (P = 0.02 and P = 0.04).

Nal-IRI + 5FU/LV therapy may be a safe and effective option as a second- or later-line treatment, particularly for patients who have not previously received mFFX therapy. For patients who received prior mFFX exposure, a longer IFI and lower CAR may indicate greater potential benefit, thus aiding in more personalized treatment approaches.

Pan-Trk immunohistochemistry has become an affordable screening tool for tumors harboring NTRK1 - 3-rearrangements. However, false positive staining has been addressed especially in tumors with mesenchymal origin. As a positive staining triggers reflex testing, a better understanding about pan-Trk immunohistochemistry in these tumors has become necessary. In this work, we extensively studied pan-Trk IHC in a large cohort of mesenchymal neoplasms using two antibody clones: EPR17341 (RTU Assay, Roche/Ventana) and A7H6R (Cell Signaling Technologies). Whole slide sections of 809 individual cases, including 35 subtypes of mesenchymal neoplasms, were analyzed by two different pan-Trk antibodies. Any positivity above background in > 1% of tumor cells was classified as positive. Positive stained cases were molecularly analyzed. The specificity of clone EPR17341 was 78% and showed 21.9% false positive staining (177/809). Forty-five percent (80/177) of the false positive stained cases harbored a non-NTRK-gene fusion. When comparing the two antibodies in mesenchymal neoplasms, clone A7H6R showed 80% less false positive stains compared to clone EPR17341. Additionally, three tumors harboring a NTRK1-fusion were newly identified (0.4%) and reclassified in our cohort. Our work showed a high false positive rate in mesenchymal neoplasms using clone EPR17341. Clone A7H6R demonstrated a higher specificity and therefore could be considered in clinical practice for screening mesenchymal tumors for NTRK1 - 3-rearrangements, eventually leading to less unnecessary reflex testing.

Oncogenic gene fusions occur across a broad range of cancers and are a defining feature of some cancer types. Cancers driven by gene fusion products tend to respond well to targeted therapies, where available; thus, detection of potentially targetable oncogenic fusions is necessary to select optimal treatment. Detection methods include non-sequencing methods, such as fluorescence in situ hybridization and immunohistochemistry, and sequencing methods, such as DNA- and RNA-based next-generation sequencing (NGS). While NGS is an efficient way to analyze multiple genes of interest at once, economic and technical factors may preclude its use in routine care globally, despite several guideline recommendations. The aim of this review is to present a summary of oncogenic gene fusions, with a focus on fusions that affect tyrosine kinase signaling, and to highlight the importance of testing for oncogenic fusions. We present an overview of the identification of oncogenic gene fusions and therapies approved for the treatment of cancers harboring gene fusions, and summarize data regarding treating fusion-positive cancers with no current targeted therapies and clinical studies of fusion-positive cancers. Although treatment options may be limited for patients with rare alterations, healthcare professionals should identify patients most likely to benefit from oncogenic gene fusion testing and initiate the appropriate targeted therapy to achieve optimal treatment outcomes.

Pediatric gliomas are the most frequently occurring central nervous system tumors in children. While targeted therapies have been widely applied in the treatment of many adult cancers, their use in pediatric gliomas has lagged behind. However, recent advances in multiomics profiling of pediatric gliomas, coupled with the approval of inhibitors against Raf serine/threonine kinase (RAF), isocitrate dehydrogenase 1/2 (IDH1/2) and neurotrophic receptor tyrosine kinase (NTRK), have spurred significant progress in this field. In light of these developments, this review aims to provide a comprehensive overview of current advancements and the evolving landscape of targeted therapeutic strategies and approaches for pediatric gliomas.

Data analyzed in this study were obtained from the literature from PubMed, as well as other online databases and websites, including ClinicalTrials.gov and the Pediatric Neuro-Oncology Consortium.

Based on findings from multiomics profiling, significant insights have been gained into the genetic and molecular landscape of pediatric gliomas, enabling the identification of key mutations and potentially targetable lesions. These advancements provide rationales for the development of more precise treatment strategies and targeted therapies. Recent approvals of targeted therapies and ongoing clinical trials in pediatric gliomas are converging on the targeting of key signaling molecules and metabolic pathways.

In the molecular era, targeted therapies offer new hope for more effective and personalized treatment options for pediatric glioma patients. By developing and tailoring treatments to target specific molecular and metabolic vulnerabilities, targeted therapies have the potential to improve the clinical management of pediatric gliomas, ultimately enhancing both the treatment experience and overall prognosis of these patients.

The use of Comprehensive Genomic Profiling (CGP) in clinical practice to detect broad-spectrum therapeutic, prognostic, and predictive biomarkers, including tumor mutational burden (TMB), microsatellite instability (MSI), somatic BRCA (sBRCA) and other homologous recombination repair genes (HRRs) provides a more cost-efficient and tissue-preserving approach than serial single-biomarker analysis. A total of 1000 biopsy-proven cancer patients at the HCG cancer center were profiled in an IRB-approved prospective study. The findings were discussed in the multidisciplinary molecular tumor board (MTB), and recommendations were documented in electronic medical records (EMRs) for clinical management and follow-up. A total of 1747 genomic alterations were detected (mean 1.7 mutations/sample), with 80% of patients having genetic alterations with therapeutic and prognostic implications (Tier I-32%, Tier II-50%). CGP revealed a greater number of druggable genes (47%) than did small panels (14%). Tumor-agnostic markers for immunotherapy (IO) were observed in 16% of the current cohort, based on which IO was initiated. In 13.5% of the cohort, alterations in the HRR pathway including sBRCA (5.5%) were detected providing an option for treatment with platinum or PARP inhibitors. Other significant alterations included those in EGFR, KRAS/BRAF, PIK3CA, cKIT, PDGFRA, ARID1A, ARID2, and FGFR. RNA sequencing revealed 55 + RNA alterations, including those in TMPRSS-ERG, RPS6KB1-VMP1, EML4-ALK, NTRK, PDGFRA and EWSR. Clinical outcome data were available via EMR for 618 patients (62%), out of whom 419 patients had druggable mutations (67%; 95% CI 88.9-93.9%) and 39 patients had 1 or more mutations with prognostic implications. However, only 200 patients (44%; 95% CI 39.1-48.1%) were included in the MTB discussion. Based on genomics reports, the treatment regimen was changed for 137 and 61 patients with and without clinical inputs from the MTB, respectively. The overall change in therapy based on CGP in the clinical cohort was 43%, which was greater in patients enrolled for MTB than in patients who had not undergone MTB. At the interim analysis, with a median follow-up of 18 months (range 12-24 months) after the change in therapy as per genomics report, 97 patients (71%) were found to be alive thus establishing the importance of CGP and MTB in personalized genomics-driven treatment.

In recent years, pembrolizumab has demonstrated significant efficacy in treating tumors characterized by a high tumor mutational burden and high microsatellite instability. Tropomyosin receptor kinase (TRK) inhibitors have shown considerable efficacy against tumors harboring neurotrophic receptor tyrosine kinase (NTRK) fusion genes, highlighting the growing importance of personalized medicine in cancer treatment. Advanced sequencing technologies enable the rapid analysis of numerous genetic abnormalities in tumors, facilitating the identification of patients with positive biomarkers. These advances have increased the likelihood of providing effective, tailored treatments. NTRK fusion genes are present in various cancer types, including sarcomas, and the TRK inhibitors larotrectinib and entrectinib have been effectively used for these malignancies. Consequently, the treatment outcomes for NTRK fusion-positive tumors have improved significantly, reflecting a shift toward more personalized therapeutic approaches. This review focuses on NTRK fusion-positive sarcomas and comprehensively evaluates their epidemiology, clinical features, and radiological and histological characteristics. We also investigated the treatment landscape, including the latest methodologies involving TRK inhibitors, and discussed the long-term efficacy of these inhibitors, and their optimal order of use. Notably, larotrectinib has demonstrated a high response rate in infantile fibrosarcoma, and its efficacy has been confirmed even in advanced cases. However, further research is warranted to optimize treatment duration and subsequent management strategies. The accumulation of clinical cases worldwide will play a pivotal role in refining the treatment approaches for tumors associated with NTRK fusion genes.

A subset of gastrointestinal stromal tumors (GISTs) lacks the common mutations in KIT/PDGFRa genes. This is a rare and heterogeneous group of challenging GISTs due to their diversity and absence of sensitivity to the tyrosine kinase inhibitor (TKI) imatinib.

In this manscript, we review the pathogenesis, natural history, diagnostic features and management of KIT/PDGFRa wild-type (WT) GISTs, including SDH-deficient GISTs, GISTs with mutations in the RAS/RAF pathway, and quadruple WT GISTs which lack mutations in either KIT/PDGFRa and SDH genes or components of the RAS/RAF pathway, and syndromic GISTs as well as GISTs with rare KIT/PDGFRa mutations.

Patients should be managed in reference centers. There has been progress in the understanding of the biology of these GISTs, and promising therapeutic targets have been identified. In SDH-deficient GISTs, the TKI olverembatinib has shown encouraging clinical activity but requires further clinical validation, while the HIF2a inhibitor bezultifan and temozolomide alone or in combination with the death receptor agonist 5 are under clinical investigation. Targeting the RAS/RAF pathway in RAS/RAF-mutated GISTs warrants evaluation in clinical trials. Rare molecular alterations in quadruple WT GISTs require investigation for their oncogenic potential. Collaborative research and patient advocacy is critical for these extremely rare tumors.

Recent advances in molecular profiling have enabled the identification of potential therapeutic targets for biliary tract cancer (BTC). However, in patients with BTC, molecular profiling is hindered by challenges in obtaining adequate tissue samples. Circulating tumor DNA (ctDNA) may offer an alternative to tissue-based analysis. Herein, we aimed to assess the concordance between ctDNA and tissue genomic profiling in a large cohort of Asian patients with advanced BTC, and to evaluate the feasibility of liquid biopsy in BTC treatment.

This study included patients with systemic treatment-naive advanced BTC, treated at CHA Bundang Medical Center between January 2019 and December 2022. We enrolled patients with available baseline tissue-based next-generation sequencing, and sufficient plasma samples for ctDNA analysis (AlphaLiquid®100 from IMBdx).

Among 102 enrolled patients, 49.0% had intrahepatic cholangiocarcinoma, 26.5% extrahepatic cholangiocarcinoma, and 24.5% gallbladder cancer. The concordance between intra-patient ctDNA and tumor tissue mutations revealed a sensitivity of 84.8%, and positive predictive value of 79.4%. ctDNA revealed targetable alterations in 34.3% of patients - including FGFR2 fusions, IDH1 mutations, microsatellite instability-high, ERBB2 amplifications, PIK3CA mutations, BRCA1/2 mutations, and MET amplifications. Notably, a novel FGFR2-TNS1 fusion was identified in ctDNA, which was not targeted in the tissue NGS panel. A high maximum somatic variant allele frequency in ctDNA was associated with poor prognosis after gemcitabine/cisplatin-based chemotherapy, in terms of both overall survival (p = 6.9 × 10-6) and progression-free survival (p = 3.8 × 10-7).

Among patients with advanced BTC, ctDNA-based genotyping showed acceptable concordance with tissue genomic profiling. Liquid biopsy using ctDNA could be a valuable complement to tissue-based genomic analysis in BTC.

Our study is the first large-scale investigation of the clinical utility of liquid biopsy, focusing on circulating tumor DNA (ctDNA), as an alternative to conventional tumor tissue analysis, among Asian patients with advanced biliary tract cancer. The results demonstrated acceptable concordance between analysis of ctDNA vs. tissue for identifying therapeutic targets and potentially actionable genetic alterations. This indicates that ctDNA analysis can provide critical insights regarding advanced biliary tract cancer treatment, particularly in cases where it is challenging to obtain or analyze tumor tissue.

Sarcomas are a rare and heterogeneous group of mesenchymal malignant tumors and account for approximately 1% of all adult cancers and around 20% of all pediatric solid tumors in Europe. Technology advances have enabled a more accurate and efficient characterization of the molecular mechanisms underlying the pathogenesis of sarcoma subtypes and revealed novel and unexpected therapeutic targets with prognostic/predictive biomarkers, namely the neurotrophic tyrosine receptor kinase (NTRK) gene fusion. The NTRK fusion assessment has recently become a standard part of management for patients with unresectable locally advanced or metastatic cancers and has been identified in various tumor types. In the more prevalent adult and pediatric sarcomas, NTRK fusions are present in 1% and 20%, respectively, and in more than 90% of very rare subsets of tumors. The inhibition of TRK activity with first-generation TRK inhibitors has been found to be effective and well tolerated in adult and pediatric patients, independently of the tumor type. Overall, the therapeutic benefit to those patients compensates for the difficulties of identifying NTRK gene fusions. However, the rarity and diagnostic complexity of NTRK gene fusions raise several questions and challenges for clinicians. To address these issues, an expert panel of medical and pediatric oncologists, radiologists, surgeons, orthopedists, and pathologists reviewed the recent literature and discussed the current status and challenges, proposing a diagnostic algorithm for identifying NTRK fusion sarcomas. The aim of this article is to review the updated information on this issue and to provide the experts' recommendations and practical guidance on the optimal management of patients with soft tissue sarcomas, infantile fibrosarcoma, gastrointestinal stromal tumors, and osteosarcoma.

The TRK inhibitor larotrectinib is US Food and Drug Administration approved for NTRK fusion-positive solid tumors that lack a satisfactory alternative or have progressed after treatment but has not been systematically studied as a frontline therapy with a defined duration of treatment. ADVL1823 evaluated larotrectinib in patients with newly diagnosed NTRK fusion-positive solid tumors with response-adapted duration of therapy and local control.

Patients received larotrectinib twice daily in 28-day cycles for a predefined duration of treatment, ranging from 6 to 26 cycles depending on response to therapy and surgical resectability. The primary end point was the objective response rate (ORR) within six cycles in patients with infantile fibrosarcoma (IFS); patients with other histologic diagnoses were analyzed in a separate cohort. Secondary objectives included event-free survival (EFS) and overall survival (OS).

Thirty-three patients were enrolled: 18 with IFS and 15 with other solid tumors. The ORR within six cycles was 94% (17/18; 95% adjusted CI, 72.7 to 98.6) among children with IFS and 60% (9/15; 95% CI, 32.3 to 83.7) among children with other solid tumors. Six percent (2/33; 95% CI, 0.7 to 22.2) patients developed progressive disease while on therapy. Two-year EFS and OS among these groups were 82.2% (95% CI, 54.3 to 93.9) and 93.8% (95% CI, 63.2 to 99.1) for IFS and 80% (95% CI, 50.0 to 93.1) and 93.3% (95% CI, 61.3 to 99.0) for other solid tumors, respectively. Patients undergoing surgical resection of their tumor had prolonged EFS, with only 1 of 16 such patients experiencing disease progression. Four of 33 patients had dose-limiting toxicities.

Larotrectinib is highly active in patients with newly diagnosed NTRK fusion-positive solid tumors. Larotrectinib should be a frontline option for patients with IFS and other NTRK fusion-positive solid tumors. Local control with surgical resection remains important in the treatment of patients with IFS.

Larotrectinib is a highly selective tropomyosin receptor kinase (TRK) inhibitor with efficacy in children with TRK fusion tumors. We evaluated patient outcomes after elective discontinuation of larotrectinib in the absence of disease progression in a protocol-defined wait-and-see subset analysis of eligible patients where treatment resumption with larotrectinib was allowed if disease progressed. We also assessed the safety and efficacy of larotrectinib in all pediatric patients with sarcoma. This cohort included 91 patients (younger than 18 years) from two clinical trials: infantile fibrosarcoma (49), other soft tissue sarcomas or related mesenchymal tumors (41), and bone sarcoma (1). Treatment-related adverse events were of maximum grade 1 or 2 in 25% and 25% of patients, respectively. The overall response rate was 87% (95% CI, 78 to 93). In the wait-and-see analysis, 47 patients discontinued larotrectinib. Median time from discontinuation to disease progression was not reached. Sixteen patients had tumor progression during the wait-and-see period. All 16 patients resumed larotrectinib, and 15 (94%) achieved disease control, with 11 objective responses. Larotrectinib continues to demonstrate durable responses with favorable safety in children with TRK fusion sarcomas. Treatment discontinuation is feasible in select patients with objective response and clinical benefit noted in those who have disease progression after elective treatment discontinuation.

Gene fusions represent important oncogenic driver mutations resulting in aberrant cellular signaling. In up to 17% of all solid tumors at least one gene fusion can be identified. Precision therapy targeting fusion gene signaling has demonstrated effective clinical benefit. Advancements in clinically relevant next-generation sequencing and bioinformatic techniques have enabled expansion of therapeutic opportunity to subpopulations of patients with fusion gene expression. Clinically, tyrosine inhibitors have shown efficacy in treating fusion gene expressing cancers. Fusion genes are also clonal mutations, meaning it is a personal cancer target involving all cancer cells of that patient, not just a subpopulation of cancer cells within the cancer mass. Thus, both fusion signal disruption and immune signal targeting are effective therapeutic directions. This review discusses fusion gene targeting, therapeutic resistance, and molecular biomarkers.

Neurotrophic tyrosine receptor kinase gene fusions are oncogenic drivers of various solid tumors. Larotrectinib is a highly selective tropomyosin receptor kinase (TRK) inhibitor approved for patients with TRK fusion cancer on the basis of single-arm trials. This study was a matched comparative effectiveness study of larotrectinib in clinical trials versus standard of care (SOC) in the real-world (RW) setting.

Adult patients with advanced/metastatic TRK fusion non-small cell lung cancer, colorectal cancer, soft tissue sarcoma, thyroid cancer, or salivary gland carcinoma were included. Deduplicated data from RW patients were from US and ex-US data sources. Patients in the larotrectinib cohort (pooled data from three trials, ClinicalTrials.gov identifiers: NCT02122913, NCT02576431, and NCT02637687) were matched 1:1 to RW patients on the basis of tumor type and line of therapy (LOT). A propensity score (weighting) model was used to balance key characteristics between cohorts. The primary outcome was overall survival (OS).

In total, 164 patients were matched 1:1 on tumor type and LOT (82 in each cohort). Balance in the baseline covariates was achieved after weighting. Larotrectinib-treated patients had longer OS (median, not reached [NR] v 37.2 months; hazard ratio [HR], 0.44 [95% CI, 0.23 to 0.83]), time to next treatment (median, NR v 10.6 months; HR, 0.22 [95% CI, 0.13 to 0.38]), duration of therapy (median, 30.8 v 3.4 months; HR, 0.23 [95% CI, 0.15 to 0.33]), and progression-free survival (median, 36.8 v 5.2 months; HR, 0.29 [95% CI, 0.18 to 0.46]) compared with RW patients after propensity score weighting.

In TRK fusion cancers, treatment with larotrectinib was associated with longer OS and prolonged time to event compared with SOC in all categories measured. These RW data provide context to support larotrectinib effectiveness in this population.

Multigene sequencing technologies provide a foundation for targeted therapy and precision oncology by identifying actionable alterations and enabling the development of treatments that substantially improve clinical outcomes. This review emphasizes the importance of having a molecular compass guiding treatment decision-making through the multitude of alterations and genetic mutations, showcasing why NGS plays a pivotal role in modern oncology.

Cancers affecting < 6/100,000/year are classified as rare, but they account for up to 25% of all cancers and are associated with worse 5-year survival than common cancers. Early-phase clinical trials (EPCTs) may represent a viable treatment option for patients with rare cancers as they have evolved significantly with novel designs and the increasing use of precision medicine.

A retrospective study of patients with rare cancers referred to a large EPCT team at a UK specialist centre over 5 years (2016-2020) was conducted. Patient demographics, medical and oncological history, genomic variants, EPCT participation, responses and survival outcomes were analysed.

In total, 240 patients with rare cancers were included. The mean age at diagnosis was 51.7 years (range 16-84), 54.2% of the patients were female. The most frequent rare cancers originated from the digestive system (27.1%), female genital tract (20%) and head and neck (H + N) (18.3%). Molecular profiling was offered to 45.5% of the population, median number of gene alterations was 3 per patient (range 1-20) while actionable gene alterations were reported in 60.2% (n = 50) of those with identified gene aberrations. Fifty-one patients participated in EPCTs, with 39.2% achieving SD and 11.8% PR. Median PFS for trial participants was three months (95% CI 1.12 - 4.88) while median OS in the trial patients was 16 months (95% CI 9.10 - 22.90) compared to 7 months for non-trial participants (95% CI 5.50 - 8.51). Finally, poor Royal Marsden Hospital (RMH) prognostic score (2-3) was correlated with worse survival when controlling for age and sex (HR 1.714, 95% CI 1.19 - 2.46, p = 0.004).

Participation of patients with rare cancers in EPCTs may be associated with a survival benefit and lead to the development of new treatments for these patients. Moreover, expanded use of precision medicine is paramount as it can inform targeted treatment selection in this heterogenous group.

The development of targeted therapy with small-molecule tyrosine kinase inhibitors and immunotherapy with immune checkpoints inhibitors has ushered in the era of precision medicine in treating lung cancer, which remains the leading cause of cancer-related deaths worldwide. Both targeted therapy and immunotherapy have significantly improved the survival of patients with metastatic non-small-cell lung cancer (NSCLC). Additionally, recent groundbreaking studies have demonstrated their efficacy in both the perioperative setting and following concurrent chemoradiotherapy in early-stage NSCLC. Despite significant advancements in first-line treatment options, disease progression remains inevitable for most patients with advanced NSCLC, necessitating the exploration and optimization of subsequent therapeutic strategies. Emerging novel agents are expanding treatment options in the first-line setting and beyond. Recently, emerging bispecific antibodies have shown enhanced efficacy. For instance, amivantamab has been approved as a treatment for epidermal growth factor receptor (EGFR)-mutant NSCLC, including those with EGFR exon 20 insertion mutations. Additionally, antibody-drug conjugates (ADCs), including HER2-targeting trastuzumab deruxtecan, TROP2-targeting ADCs, HER3-targeting patritumab deruxtecan, and MET-targeting telisotuzumab vedotin, have demonstrated promising outcomes in several clinical trials. This review summarizes the recent advancements and challenges associated with the evolving NSCLC therapeutic landscape.

Anaplastic thyroid cancer (ATC) is the rarest but also the most aggressive carcinoma entity of the thyroid gland. In recent years, treatment options have evolved and molecular oncological treatment approaches have gained in importance. The neoadjuvant use of these innovative therapies has the potential to convert previously unresectable tumors into a resectable state, thereby expanding surgical options and significantly improving the prognosis of patients. This article provides recommendations relevant for surgery for the diagnostics and treatment of ATC, based on a current literature review and the discussions of the S3 guideline conferences.

Rare diseases, also known as orphan diseases, are a group of disorders that affect a small percentage of the population. Despite individually affecting a small number of people, collectively, they impact millions worldwide. This is particularly significant in paediatric patients, highlighting the global scale of the issue. This review delves into the exact prevalence of rare diseases among children and adolescents and their diverse impact on the quality of life of patients and their families. The review sheds light on the complex interplay of genetic and environmental factors contributing to these conditions and the diagnostic challenges and delays often encountered in identifying and categorising these diseases. It is noted that although there have been significant strides in the field of genomic medicine and the development of orphan drugs, effective treatments remain limited. This necessitates a comprehensive, multidisciplinary approach to management involving various specialities working closely together to provide holistic care. Furthermore, the review addresses the psychosocial and economic burdens faced by families with paediatric patients suffering from rare diseases, highlighting the urgent need for enhanced support mechanisms. Recent technological and therapeutic advancements, including genomic sequencing and personalized medicine, offer promising avenues for improving patient outcomes. Additionally, the review underscores the role of policy and advocacy in advancing research, ensuring healthcare access, and supporting affected families. It emphasises the importance of increased awareness, education, and collaboration among healthcare providers, researchers, policymakers, and patient advocacy groups. It stresses the pivotal role each group plays in improving the diagnosis, treatment, and overall quality of life for paediatric patients with rare diseases.

Hepatobiliary cancers are heterogeneous and molecularly complex. Recent advances in next-generation sequencing (NGS) have enhanced the understanding of their molecular landscape and enabled deployment of biomarker-based gene- and immune-targeted therapies. This review examines the role of molecular testing and targeted therapies in these malignant neoplasms.

Patients with hepatobiliary cancers have poor outcomes. Precision oncology studies have shown that while many common molecular alterations are not currently targetable in hepatocellular carcinoma (HCC), a large number of actionable alterations characterize biliary tract cancers (BTCs), with several therapies now approved by the US Food and Drug Administration. Immunotherapy is increasingly adopted in clinical practice, either as monotherapy or combined with cytotoxic chemotherapy, for both HCC and BTCs. Moreover, multiple solid cancer tumor-agnostic therapies are approved (larotrectinib, entrectinib, and repotrectinib for NTRK fusions; selpercatinib for RET fusions; dabrafenib and trametinib combination for BRAF V600E mutations; dostarlimab or pembrolizumab for tumors with high microsatellite instability and pembrolizumab for tumor mutation burden ≥10 mutations/megabase), highlighting the need for NGS as well as ERBB2 (formerly HER2) immunohistochemistry (IHC) (with the recent approval of solid tissue-agnostic deruxtecan trastuzumab for ERBB2-positive [IHC 3+] cancer) across cancers. N-of-1 clinical trials using customized drug combinations matched to the tumor's molecular profile have yielded encouraging results and provide a promising framework for future clinical trial design.

Molecular testing and gene- and immune-targeted therapies are transforming hepatobiliary cancer treatment. Tumor-agnostic and N-of-1 clinical trials have challenged traditional clinical trial paradigms and provide the foundation for truly personalized oncology for patients with these aggressive cancers. Further work is needed to determine how to leverage these novel approaches into the management of operable disease.

The US Food and Drug Administration approves tissue-agnostic therapies to target tumor biomarkers regardless of tumor type. In light of the growing number of such approvals in recent years, a better understanding of their relative clinical benefit across cancer types is required. To address this need, we analyzed tissue-agnostic indications (TMB-High, MSI-High/MMRd, BRAFV600E mutations, and NTRK and RET fusions) in a database of 295,316 molecularly-profiled tumor samples with associated clinical outcomes data. Here, we show that 21.5% of tumors harbored at least one of the tissue-agnostic indications investigated, including 5.4% lacking a cancer-specific indication. Our analysis reveals poor uptake of targeted therapies for rare NTRK fusions, significant differences in pembrolizumab-associated outcomes across tumor types for TMB-High and MSI-High/MMRd, as well as clinical benefits in tumor types and drugs of the same class not investigated in the pivotal clinical trials. These results demonstrate that treatment effects are not necessarily tissue-agnostic, and suggest possible expansion of therapeutic avenues for a given tissue-agnostic indication.

Cardiac angiosarcoma is a rare, aggressive malignancy with limited treatment options. Both sporadic and familial cases occur, with recent links to germline POT1 mutations. The genomic landscape of this disease is poorly understood.

We conducted comprehensive genomic profiling of cardiac angiosarcoma to assess the burden of germline predisposition and identify other recurrent genomic alterations of clinical significance.

Six patients were female, and four were male. The median age at presentation was 40 years (range, 21-69 years). All cases with available follow-up exhibited an aggressive clinical course (6/8 patients died of disease). KDR alterations, including novel structural variants, were found in 9/11 cases at a rate significantly higher than that in noncardiac angiosarcomas. POT1 mutations were present in 45.5% of cardiac angiosarcoma cases. In three of five POT1-mutant cases, the germline status was confirmed through testing of normal tissue, and in one additional case, the germline status was inferred with high probability through allele frequency analysis. Additionally, we identified novel recurrent MED12 exon 2 mutations in POT1 wild-type cardiac angiosarcoma, suggesting an alternative path to cardiac angiosarcoma oncogenesis.

Cardiac angiosarcoma demonstrates a unique genetic profile, distinct from noncardiac angiosarcoma. This study highlights the role of germline POT1 burden on cardiac angiosarcoma development and demonstrates recurrent MED12 alterations for the first time. The reported KDR variants provide a potential avenue for the treatment of this aggressive disease. Given the prevalence of germline POT1 mutations reported in this study, germline genetic testing should be considered in patients diagnosed with cardiac angiosarcoma.

The poor prognosis for high-grade serous ovarian cancer (HGSOC), the dominant subtype of ovarian cancer, reflects its aggressive nature, late diagnosis, and the highest mortality rate among all gynaecologic cancers. Apart from late diagnosis, the main reason for the poor prognosis and its unsuccessful treatment is primarily the emergence of chemoresistance to carboplatin. Although there is a good response to primary treatment, the disease recurs in 80% of cases, at which point it is largely resistant to carboplatin. The introduction of novel targeted therapies in the second decade of the 21st century has begun to transform the treatment of HGSOC, although their impact on overall survival remains unsatisfactory. Targeting the specific pathways known to be abnormally activated in HGSOC is especially difficult due to the molecular diversity of its subtypes. Moreover, a range of molecular changes are associated with acquired chemoresistance, e.g., reversion of BRCA1 and BRCA2 germline alleles. In this review, we examine the advantages and disadvantages of approved targeted therapies, including bevacizumab, PARP inhibitors (PARPis), and treatments targeting cells with neurotrophic tyrosine receptor kinase (NTRK), B-rapidly accelerated fibrosarcoma (BRAF), and rearranged during transfection (RET) gene alterations, as well as antibody-drug conjugates. Additionally, we explore promising new targets under investigation in ongoing clinical trials, such as immune checkpoint inhibitors, anti-angiogenic agents, phosphatidylinositol-3-kinase (PI3K) inhibitors, Wee1 kinase inhibitors, and ataxia telangiectasia and Rad3-related protein (ATR) inhibitors for platinum-resistant disease. Despite the development of new targeted therapies, carboplatin remains the fundamental medicine in HGSOC therapy. The correct choice of treatment strategy for better survival of patients with advanced HGSOC should therefore include a prediction of patients' risks of developing chemoresistance to platinum-based chemotherapy. Moreover, effective targeted therapy requires the selection of patients who are likely to derive clinical benefit while minimizing potential adverse effects, underscoring the essence of precision medicine.

While biomarker-guided treatments and NGS-based approaches are refining precision medicine, they are not universally applicable. The gap between the genomic characterization of tumors and their functional behavior is becoming increasingly evident. There is an escalating demand for functional assays that can customize cancer treatments for individual patients and bridge this gap. We have developed OncoFlow, an integrated microfluidic platform that automates viability assays. This platform customizes treatment options by assessing the functional responses of a patient's tumor cells to a specific drug panel. This study specifically addressed non-small cell lung adenocarcinoma (NSCLC) in patients presenting pleural effusion. We used the NCI-H2228 adenocarcinoma cell line, which harbors the EML4-ALK fusion oncogene, to develop and fine-tune the viability assay. Cells cultivated in microfluidic chambers were treated with various concentrations of the tyrosine kinase inhibitors alectinib and crizotinib, and the cytotoxic effects were measured. The results were consistent with those from conventional cell culture methods, thereby validating the assay's reliability. Next, pleural effusion samples from six NSCLC patients, four of them harboring the EML4-ALK rearrangement were tested with alectinib and crizotinib using the OncoFlow system. Monitoring and analysis of cell viability showed varied sensitivities to crizotinib, while all samples exhibited resistance to alectinib. These findings underscore OncoFlow's potential to enhance physician decision-making and customize treatment plans, ultimately improving patient outcomes.

Background and Objectives: Neurotrophic receptor tyrosine kinase 3 (NTRK3) is a member of the tropomyosin receptor kinase family of receptor tyrosine kinases, which play a crucial role in neural development. However, owing to the limited number of studies about NTRK3 and cancer, we aimed to investigate NTRK3 as a potential prognostic marker for breast cancer (BC). Materials and Methods: We conducted a comprehensive analysis of NTRK3 expression in BC using the Tumor Immune Estimation Resource, Gene Expression Profiling Interactive Analysis 2, and Kaplan-Meier Plotter databases. We also explored the association between NTRK3 expression and tumor-infiltrating immune cells. Results: Low NTRK3 expression showed poorer prognosis in BC, as well as with T stage, pathology, and the Luminal subtype. In BC (BRCA), NTRK3 was positively correlated with CD4+ T cell, CD8+ T cell, macrophage, and neutrophil infiltration. Conclusions: These results suggest that NTRK3 may serve as a prognostic biomarker and provide novel insights into tumor immunology in BC. Therefore, NTRK3 represents a potential diagnostic and therapeutic target for BC treatment.

Traditional anatomic pathologic classification of cancer is based on tissue of origin and morphologic and immunohistochemical characterization of the malignant cells. With the technological improvements of massively parallel or next-generation sequencing, oncogenic drivers that are shared across different tumor types are increasingly being identified and used as pan-cancer biomarkers. This approach is reflected in the growing list of Food and Drug Administration-approved tumor-agnostic therapies, including pembrolizumab in the setting of microsatellite instability and high tumor mutational burden, larotrectinib and entrectinib for solid tumors with NTRK fusions, and combined dabrafenib-trametinib for BRAF V600E-mutated neoplasms. Several other biomarkers are currently under investigation, including fibroblast growth factor receptor (FGFR), RET, and ROS1 fusions; ERBB2 amplification; and mutations in the AKT1/2/3, NF1, RAS pathway and (mitogen-activated protein kinase (MAPK) pathway. As molecular assays are increasingly incorporated into routine tumor workup, the emergence of additional pan-cancer biomarkers is likely to be a matter more of "when" than "if." In this review, we first explore some of the conceptual and technical considerations at the intersection of surgical and molecular pathology, followed by a brief overview of both established and emerging molecular pan-cancer biomarkers and their diagnostic and clinical applications.

Little is known about metabolic vulnerabilities in oncogene-driven lung cancer. Here, we perform a phosphoproteomic screen in anaplastic lymphoma kinase (ALK)-rearranged ("ALK+") patient-derived cell lines and identify guanylate kinase 1 (GUK1), a guanosine diphosphate (GDP)-synthesizing enzyme, as a target of ALK signaling in lung cancer. We demonstrate that ALK binds to and phosphorylates GUK1 at tyrosine 74 (Y74), resulting in increased GDP biosynthesis. Spatial imaging of ALK+ patient tumor specimens shows enhanced phosphorylation of GUK1 that significantly correlates with guanine nucleotides in situ. Abrogation of GUK1 phosphorylation reduces intracellular GDP and guanosine triphosphate (GTP) pools and decreases mitogen-activated protein kinase (MAPK) signaling and Ras-GTP loading. A GUK1 variant that cannot be phosphorylated (Y74F) decreases tumor proliferation in vitro and in vivo. Beyond ALK, other oncogenic fusion proteins in lung cancer also regulate GUK1 phosphorylation. These studies may pave the way for the development of new therapeutic approaches by exploiting metabolic dependencies in oncogene-driven lung cancers.

Tropomyosin receptor kinase (TRK) has emerged as a promising therapeutic target in cancers driven by NTRK gene fusions. Herein, we report a highly potent TRK inhibitor, C11, developed using bioisosteric replacement and computer-aided drug design (CADD) strategies. Compound C11 demonstrated significant antiproliferative effects against TRK-dependent cell lines (Km-12), and exhibited a dose-dependent inhibition of both colony formation and cell migration. Mechanistic study revealed that C11 induced cancer cell death by arresting the cell cycle, triggering apoptosis, and reducing phosphorylated TRK levels. In vitro stability assays showed that compound C11 possessed excellent plasma stability (t1/2 > 480 min) and moderate liver microsomal stability (t1/2 = 38.9 min). Pharmacokinetic evaluation further indicated an oral bioavailability of 15.2 % for compound C11. These results highlight compound C11 as a promising lead compound for the further development of TRK inhibitors.

Soft tissue sarcomas [STSs] are rare tumors of mesodermal origin that arise in diverse tissues such as muscles, fat, and nerves. There are over 100 subtypes of STS, each with distinct clinical behaviors and responses to treatment. Recent advances in treatment have moved towards histology-specific approaches, emphasizing the integration of pathological, immunohistochemical, and molecular features to guide treatment. Localized STS is primarily treated with surgery, often supplemented by neoadjuvant or adjuvant radiation and/or chemotherapy. However, about half of patients with localized disease will progress to an advanced stage, which is typically managed with systemic therapies including anthracycline-based chemotherapy such as doxorubicin or epirubicin. Despite these treatments, the survival rates for most subtypes of advanced metastatic STS remain relatively low. While anthracycline-based chemotherapy remains the mainstay of treatment, ongoing research into the biology of STSs is enhancing our understanding and approach to these complex tumors with an expansion beyond chemotherapy to include targeted therapy and immunotherapy to improve response rates and survival outcomes. This review focuses on STS other than gastrointestinal stromal tumors [GISTs], examines the current systemic treatment strategies, highlights recent advances, and explores future directions in the systemic therapy of sarcoma patients.

Accurate detection of oncogenic gene fusions is important for histological diagnosis of a subset of tumours. Some fusions are also the target of precision therapies. We describe our validation and early diagnostic results for the detection of fusions using the commercially available Illumina TruSight RNA Fusion Panel (TRFP) and the Arriba fusion detection algorithm. Retrospective validation showed that this assay demonstrated high accuracy (94% positive predictive agreement) for a wide variety of fusions. Prospective diagnostic data comprised a cohort of 131 clinical samples (102 mesenchymal tumours, 29 epithelial tumours), of which 80 were excisional specimens and 51 were small specimens, predominantly core biopsies. The test failure rate was 10.7%. We detected 64 (54.7%) clinically-actionable fusions in passed samples, including 12 (10.3%) that either changed or were critical for the diagnosis and 14 (12.0%) that were potentially therapeutically targetable. Most samples (89.7%) fulfilled criteria for partial reimbursement by the Australian Government Medical Benefits Scheme. In addition to describing the utility of an RNA-based fusion assay in cancer diagnostics, it is hoped that this study will provide practical advice for other laboratories considering introducing such a test.

In recent years, treatment options for patients with advanced biliary tract cancer (BTC) have increased significantly due to the positive results from phase 2/3 clinical trials of immune checkpoint inhibitors, combined with chemotherapy, and molecularly targeted agents. These advances have led to the need for molecular testing to identify actionable alterations and patients amenable to targeted therapies. However, these improvements have brought with them many questions and challenges, including the identification of resistance mechanisms and therapeutic sequences. In this Series paper we aim to provide an overview of the current systemic treatment options for patients with BTC, highlighting disparities in access to innovative treatments and molecular testing across European countries, which lead to inequalities in the possibilities of treating patients with advanced BTC. We also discuss how ongoing European collaborative projects, such as the COST Action Precision-BTC-Network CA22125, supported by COST (European Cooperation in Science and Technology), linked to the European Network for the Study of Cholangiocarcinoma (ENSCCA), can help overcome these disparities and improve the current scenario.