• EPID
• VMAT QA
• control-point specific QA
• log-based QA
• patient-specific QA

• Varian Medical Systems

• Gastric cancer
• Human epidermal growth factor receptor 2
• Review
• Targeted therapy

• Chinese Society of Clinical Oncology (CSCO)
• adjuvant
• chemotherapy
• diagnosis
• gastric cancer
• immunotherapy
• neoadjuvant
• radiotherapy
• surgery
• targeted therapy

• Humans
• Stomach Neoplasms/diagnosis
• Stomach Neoplasms/genetics
• Stomach Neoplasms/therapy
• Medical Oncology
• Immunotherapy
• Neoadjuvant Therapy
• China

• Image guided
• Position verification
• Treatment planning system
• Volume rotation intensity

• Chinese Society of Clinical Oncology (CSCO)
• adjuvant
• chemotherapy
• diagnosis
• gastric cancer
• immunotherapy
• neoadjuvant
• radiotherapy
• surgery
• targeted therapy

• China
• Humans
• Medical Oncology
• Societies, Medical
• Stomach Neoplasms/diagnosis
• Stomach Neoplasms/drug therapy

• beam energy
• helical tomotherapy
• intensity-modulated radiotherapy
• proximal gastric cancer
• volumetric-modulated arc therapy

• Aged
• Female
• Humans
• Male
• Middle Aged
• Photons
• Radiometry
• Radiotherapy Dosage
• Radiotherapy Planning, Computer-Assisted
• Radiotherapy, Intensity-Modulated/methods
• Retrospective Studies
• Stomach Neoplasms/radiotherapy

• Adjuvant
• Chemotherapy
• Chinese Society of Clinical Oncology (CSCO)
• Diagnosis
• Gastric cancer
• Immunotherapy
• Neoadjuvant
• Radiotherapy
• Surgery
• Targeted therapy

• China
• Humans
• Medical Oncology
• Societies, Medical
• Stomach Neoplasms/diagnosis
• Stomach Neoplasms/therapy

To retrospectively analyze dosimetric parameters of volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiotherapy (3D-CRT) delivered to extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma) to find out advantages of VMAT and conditions for definite benefits of VMAT.

Fifty patients with stage I-II gastric MALT lymphoma received VMAT (n = 14) or 3D-CRT (n = 36) between December 2005 and April 2018. Twenty-seven patients were categorized according to whether the planning target volume (PTV) overlaps kidney(s). Dosimetric parameters were analyzed by dose-volume histogram.

Radiation dose to the liver was definitely lower with VMAT in terms of mean dose (p = 0.026) and V₁₅ (p = 0.008). The V₁₅ of the left kidney was lower with VMAT (p = 0.065). For those with PTV overlapping kidney(s), the left kidney V₁₅ was significantly lower with VMAT. Furthermore, the closer the distance between the PTV and kidneys, the less the left kidney V₁₅ with VMAT (p = 0.037). Delineation of kidney(s) by integrating all respiratory phases had no additional benefit.

VMAT significantly increased monitor units, reduced treatment time and radiation dose to the liver and kidneys. The benefit of VMAT was definite in reducing the left kidney V₁₅, especially in geometrically challenging conditions of overlap or close separation between PTV and kidney(s).

• 3-D conformal radiotherapy
• Gastric MALT lymphoma
• Kidney dose
• Liver dose
• Organs at risk
• Volumetric-modulated arc therapy

Regulatory T-cell density and cytotoxic T lymphocyte density are crucial in regulating antitumor immune responses. Tumor infiltration has marked therapeutic effects in gastric carcinoma, and there is evidence that chemoradiotherapy (CRT) exhibits an immune-mediated component. In the present study, the density of CD4⁺ and CD8⁺ cells were evaluated in post-CRT surgical samples from 68 patients with gastric cancer using immunohistochemistry. The associations between T-cell density, cytotoxic T lymphocyte density and clinical survival rate were also analyzed. Cytotoxic T lymphocyte density was associated with gastric carcinoma regression grade and regulatory T-cell density was also associated with gastric carcinoma regression grade. Of the patients who had a pathologic complete response, 84 and 76% were found to have a high CD3⁺ and CD4⁺ cell density, which was significantly different to patients who had a low CD3⁺ and CD4⁺ cell density. High cytotoxic T lymphocyte density was also associated with improved survival rates of patients with gastric cancer. In conclusion, these outcomes indicated that regulatory T-cell density and cytotoxic T lymphocyte density in the tumor microenvironment were associated with the response to neoadjuvant CRT and may represent a therapeutic target for gastric cancer.

• chemoradiotherapy
• cytotoxic T lymphocyte
• gastric cancer
• regulatory T cells

Intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) are two of the main treatment techniques for cervical cancer. Whether either technique significantly reduces irradiated volumes of organs at risk (OARs) remains controversial. The aim of this study was to explore which of these treatment paradigms is the superior technique in cervical treatment, taking clinical outcomes and treatment efficiency from published findings into consideration.

PubMed, EMBASE, and Cochrane Library databases were utilized. The average percent irradiated volumes of OAR were extracted from all included studies. Dual arc results were extracted due to their superiority to single arc methods in terms of plan quality. Standard mean deviations and 95% CIs were calculated for delivery time, monitor units, and average percent irradiated volumes of OAR. Assessment of publication bias and sensitivity analyses were performed. All statistical analyses were conducted using R 3.5.0 software.

Eight studies were included in this meta-analysis. For irradiated volumes of OARs, irradiated volume of rectum receiving 40 Gy (rectum V40) was significantly decreased in VMAT compared with IMRT. However, no significant differences were observed between IMRT and VMAT plans in bladder V40 or small bowel V40/V30. In addition, delivery times and monitor units were significantly lower in the VMAT plan than in the IMRT plan.

Compared with IMRT, VMAT is significantly more protective for the rectum, suggesting that it may be an optional therapy technique for patients with cervical cancer.

• IMRT
• VMAT
• cervical cancer
• meta-analysis

To compare dosimetric parameters of intensity-modulated radiotherapy (IMRT), volumetric-modulated arc therapy (VMAT) and tomotherapy (TOMO) in the adjuvant treatment of gastroesophageal junction (GEJ)/stomach cancer. The planning goal was to maintain high target coverage while keeping the dose to the bowel and bone marrow (BM) as low as possible.

After curative surgery, 16 patients with GEJ/stomach cancer were re-planned by coplanar IMRT (five fixed beam), VMAT (double-arc), and TOMO. The dose to the planning target volume (PTV) was 45 Gy in 25 fractions. The target parameters, including the homogeneity index (HI) and conformity index (CI), and doses to the organs at risk (OARs) were analyzed.

Dosimetric parameters for PTV and OARs were comparable among the three techniques. However, TOMO provided improved conformity (CI = 0.92±0.03) and homogeneity (HI = 1.07±0.02) than IMRT (CI = 0.87±0.03; HI = 1.09±0.02; p < 0.05) and VMAT (CI = 0.86±0.03; HI = 1.09±0.02; p < 0.01). TOMO also improved dose sparing of the bowel (percentage of the volume receiving a dose of ≥ 30 Gy [V30] = 23.24±9.85) and BM (V30 = 71.66±6.15) compared with IMRT (bowel V30 = 30.02±11.74; BM V30 = 83.74±8.42; p < 0.01) and VMAT (bowel V30 = 31.88±11.59; BM V30 = 79.51±9.07; p < 0.01).

TOMO is a good option for adjuvant treatment of GEJ/stomach cancer in patients undergoing radical surgery due to its superior bowel and BM dose sparing, dose conformity and dose homogeneity; however, future studies are required to validate its clinical efficacy.

• gastric cancer
• gastroesophageal junction cancer
• helical tomotherapy
• intensity-modulated radiotherapy
• volumetric-modulated arc therapy

• Dosimetry
• Gastric cancer
• Helical tomotherapy
• Volumetric arc therapy

Adjuvant radiotherapy is an important clinical treatment for the majority of gastric cancer, a common cancer. However, radiotherapy is a double-edged sword. It is necessary to develop a method to predict radiosensitive patients who are most likely to benefit from radiotherapy. Using the publicly available data of gastric cancer from The Cancer Genome Atlas (TCGA), we developed a gene signature that predicts radiosensitive patients through estimating a new index, nominal HR (nHR) (HR product of sensitive genes), for each patient. In this study, we provided several results to validate our prediction. Cross-validation results showed that the predicted radiosensitive patients who received radiotherapy had significantly better survival than predicted radiosensitive patients who did not receive radiotherapy. After adjusting for other clinical factors, including age, sex, target therapy, histologic diagnosis, tumor stage, the benefit of radiotherapy on predicted radiosensitive patient remained significant. In addition, predicted radiosensitive patients who received radiotherapy had a significantly reduced rate of disease progression. Taken together, we have obtained a set of genes, to identify radiosensitive patients with gastric cancer. These genes may be potential biomarkers for diagnosis and treatment of gastric cancer, which could give new insight for revealing the underlying mechanism of radiosensitivity of gastric cancer.

• Gastric cancer
• density variations
• dosimetric comparison
• radiotherapy
• scanned-proton beams

• Chemotherapy
• Heart
• Lungs
• Organs at risk
• Survival

• 3d-crt
• Dosimetric comparisons
• RapidArc
• imrt
• organ preservation
• pancreatic cancer

• Conformal radiotherapy
• Gastric cancer
• Treatment plan comparison

• D2 dissection
• adjuvant
• biomarker
• chemoradiotherapy
• efficacy
• gastric cancer
• radiotherapy technique

• Gating
• Renal cell carcinoma
• Stereotactic body radiation therapy
• Volumetric arc therapy

The aim of the present study was to compare radiotherapy treatment plans for gastric cancer using intensity-modulated radiotherapy (IMRT) and single/double-arc volumetric modulated arc therapy (SA/DA-VMAT) delivery techniques. A total of 29 postoperative gastric cancer patients were enrolled in this study and each patient was scheduled 5-field IMRT (5F-IMRT), 7-field IMRT (7F-IMRT), SA-VMAT and DA-VMAT techniques. Dose-volume histogram statistics, conformal index (CI), homogeneity index (HI) and monitor units (MUs) were analyzed to compare treatment plans. The DA-VMAT plans exceeded the other three methods in terms of planning tumor volume dose and organs at risk in the kidneys, but not in the liver. DA-VMAT exhibited a better mean CI (0.87±0.03) and HI (0.10±0.01) than the other techniques. In addition, for the kidneys the dose sparing (V13, V18 and mean kidney dose) was improved by DA-VMAT plans. Similar results were observed for MUs. However, 5F-IMRT showed a marginal advantage in V30 and mean dose in normal liver when compared with DA-VMAT. The results of this study suggest that DA-VMAT provides improved tumor coverage when compared with 5F-IMRT, 7F-IMRT and SA-VMAT; however, DA-VMAT exhibits no advantage in liver protection when compared with 5F-IMRT. Further studies are required to establish differences in treatment outcomes among the four technologies.

• dosimetric comparison
• gastric cancer
• intensity-modulated radiotherapy
• volumetric modulated arc therapy