Published online Jun 28, 2021. doi: 10.3748/wjg.v27.i24.3630
Peer-review started: February 5, 2021
First decision: March 6, 2021
Revised: March 20, 2021
Accepted: May 19, 2021
Article in press: May 19, 2021
Published online: June 28, 2021
Processing time: 139 Days and 21.6 Hours
Liver transplantation (LT) presents a curative treatment option in patients with early stage hepatocellular carcinoma (HCC) who are not eligible for resection or ablation therapy. Due to a risk of up 30% for waitlist drop-out upon tumor progression, bridging therapies are used to halt tumor growth. Transarterial chemoembolization (TACE) and less commonly stereotactic body radiation therapy (SBRT) or a combination of TACE and SBRT, are used as bridging therapies in LT. However, it remains unclear if one of those treatment options is superior. The analysis of explant livers after transplantation provides the unique opportunity to investigate treatment response by histopathology.
To analyze histopathological response to a combination of TACE and SBRT in HCC in comparison to TACE or SBRT alone.
In this multicenter retrospective study, 27 patients who received liver transplantation for HCC were analyzed. Patients received either TACE or SBRT alone, or a combination of TACE and SBRT as bridging therapy to liver transplantation. Liver explants of all patients who received at least one TACE and/or SBRT were analyzed for the presence of residual vital tumor tissue by histopathology to assess differences in treatment response to bridging therapies. Statistical analysis was performed using Fisher-Freeman-Halton exact test, Kruskal-Wallis and Mann-Whitney-U tests.
Fourteen patients received TACE only, four patients SBRT only, and nine patients a combination therapy of TACE and SBRT. There were no significant differences between groups regarding age, sex, etiology of underlying liver disease or number and size of tumor lesions. Strikingly, analysis of liver explants revealed that almost all patients in the TACE and SBRT combination group (8/9, 89%) showed no residual vital tumor tissue by histopathology, whereas TACE or SBRT alone resulted in significantly lower rates of complete histopathological response (0/14, 0% and 1/4, 25%, respectively, P value < 0.001).
Our data suggests that a combination of TACE and SBRT increases the rate of complete histopathological response compared to TACE or SBRT alone in bridging to liver transplantation.
Core Tip: In patients with early-stage hepatocellular carcinoma (HCC) who are not eligible for resection or ablation, liver transplantation presents a curative treatment option. To halt tumor growth during waiting time, bridging therapies such as transarterial chemoembolization (TACE), ablation, and stereotactic body radiation therapy (SBRT) are used prior to liver transplantation. In a multicenter retrospective trial with 27 HCC patients who received either TACE or SBRT alone, or a combination of TACE and SBRT, explant histopathology was analyzed to assess treatment response. Strikingly, almost all patients in the combination group exhibited no residual vital tumor by histopathology, whereas TACE or SBRT alone resulted in significantly lower rates of complete histopathological response.