[Progress in conversion therapy for originally unresectable gastric cancer]

Abstract

Conversion therapy is adopted to achieve radical cure for patients with originally unresectable but potentially resectable late stage gastric cancer, who obtain partial or complete remission after systemic chemotherapy, to acquire relatively longer postoperative survival and recurrence-free survival. Some of the previous researches on conversion therapy for originally unresectable gastric cancer suggest that high chemotherapy response rate, high pathological response rate and R0 resection rate are associated with favorable prognosis. And the efficacy of patients with lymphatic metastasis is better than that of those with peritoneal metastasis. The protocol of conversional chemotherapy varies and so does its efficacy according to different reports. Latest clinical researches indicate that initially unresectable gastric cancer gained higher remission rate and better chance of R0 operation and consequently prolonged survival from paclitaxel based triplet chemotherapy. However, not all originally unresectable gastric cancer can benefit from conversion therapy due to the high heterogeneity of its biological behavior. Regarding the enormous number of originally unresectable gastric cancer patients, it will be a research hot spot in the field of surgical oncology, on screening criteria to select cases suitable for conversion. Exploration on conversion therapy for gastric cancer is still at initial stage, and reports that have been published are mostly single-centered with limited sample, lacking of sufficient evidence on its feasibility, safety and efficacy. Expert consensus on conversion indication, case selection, chemotherapy regimen, efficacy assessment and resection range is absent. So it is in urgent need for higher level clinical evidence to support and guide this practice. Such goal can never be achieved without joint efforts of all parties to carry out clinical trial to modify the practice of conversion therapy for late stage gastric cancer, and determine the proper selection of suitable candidates for conversion therapy, eventually to offer optimal strategy for originally unresectable gastric cancer patients. Thus, this article focuses on reviewing research progress of conversion therapy for originally unresectable late stage gastric cancer.