Conversion surgery for gastric cancer patients: A review

Abstract

Gastric cancer (GC) is the third most common cancer-related cause of death worldwide. In locally advanced tumors, neoadjuvant chemotherapy has recently been introduced in most international Western guidelines. For metastatic and unresectable disease, there is still debate regarding correct management and the role of surgery. The standard approach for stage IV GC is palliative chemotherapy. Over the last decade, an increasing number of M1 patients who responded to palliative regimens of induction chemotherapy have been subsequently undergone surgery with curative intent. The objective of the present review is to analyze the literature regarding this approach, known as “conversion surgery”, which has become one of the most commonly adopted therapeutic options. It is defined as a treatment aiming at an R0 resection after chemotherapy in initially unresectable tumors. The 13 retrospective studies analyzed, with a total of 411 patients treated with conversion therapy, clearly show that even if standardization of unresectable and metastatic criteria, post-chemotherapy resectability evaluation and timing of surgery has not yet been established, an R0 surgery after induction chemotherapy with partial or complete response seems to offer superior survival results than chemotherapy alone. Additional larger sample-size randomized control trials are needed to identify subgroups of well-stratified patients who could benefit from this multimodal approach.

Conversion Surgery in Metastatic Gastric Cancer and Cancer Dormancy as a Prognostic Biomarker

“…In this study, we have implemented a propensity score modeling, producing a matched cohort based on baseline characteristics, as well as the extent of initial biological disease, before palliative chemotherapy and response to chemotherapy. Our findings were consistent with previous studies that advocated conversion surgery if R0 resection could be achieved, even after adjusting for potential confounding factors [9,10,12,21,22]. It is noteworthy that patients who underwent conversion surgery exhibited a longer survival rate after additionally excluding early disease progression in the chemotherapy only group.…”

Successful Conversion Surgery Following Chylous Ascites After Nivolumab for Advanced Gastric Cancer

“…Due to the development of new drugs and regimens, the number of cases of conversion surgery is increasing. Most are performed for patients with advanced GC who exhibited dramatic effects on first-line chemotherapy (3). Therefore, a successful R0 resection after third-line chemotherapy is valuable and provides significant hope for peritoneal carcinomatosis of GC.…”

Optimization of perioperative approaches for advanced and late stages of gastric cancer: clinical proposal based on literature evidence, personal experience, and ongoing trials and research

“…In the aftermath of the REGATTA trial, even though some authors emphasized the beneficial role of palliative gastrectomy, Fujitani et al described no survival benefit was noted for palliative gastrectomy prior to chemotherapy [38]. Given the poor results achieved with chemotherapy alone, drug resistance or cumulative adverse effects, the possible benefits of surgical resection as a part of a multimodality treatment strategy for selected patients who responded well to the chemotherapy were evaluated [39][40][41]. In a study by Yoshida et al, conversion therapy was classified into four categories defined with respect to the biological and heterogeneous characteristics of GC [42,43]: category 1-in cases where the primary tumor and the metastatic lesion are evaluated technically resectable with good oncological margins, primary tumor resection with metastasectomy is recommended with or without NAC [42][43][44]; category 2-in cases where metastatic lesions are considered to be oncologically or technically unresectable, such as multiple liver metastases, liver lesions infiltrating the hepatic and/or Fig.…”