Gastric cancer is a major cause of cancer death, and many patients are only diagnosed when the cancer has reached an advanced stage. Neoadjuvant chemotherapy (NAC), that is, chemotherapy administered shortly before surgical treatment, could provide a method of increasing the possibility of complete resection and survival.
To evaluate the effect of neoadjuvant chemotherapy versus none for patients with resectable gastric cancer in terms of efficacy and toxicity.
Electronic databases including Cochrane Library, MEDLINE, EMBASE, CancerLit, Chinese Biomedical Literature Database (CBMDISC) and ongoing clinical trials as well as handsearching of conference proceedings, were searched to retrieve relevant data.
Randomized controlled clinical trials of neoadjuvant chemotherapy on resectable gastric cancer.
Data collection and analysis
We identified a total of 36 published citations or meeting abstracts. Thirty-two items were excluded. Of the four remaining studies, three stated random allocation but the method of randomization was unclear. Two of these employed allocation concealment by sealed envelope which was controlled by an independent party. None of the trials was double blind. All trials presented a detailed description of the number of withdrawals, dropouts and losses to follow-up.
Of the four clinical trials enrolled, there were 250 and 332 cases in total, with 106 and 126 deaths at the end of follow-up in the NAC and control group, respectively. The OR (odds ratio) was 1.05 (95%CI: 0.73-1.50), which was not statistically significant. Of the evaluable 129 patients receiving NAC, 28.7% demonstrated either a complete or a partial response. Two studies of NAC in resectable gastric cancer had resection rate data available for analysis The R0 resection rate in the NAC group was comparable to that in the control (OR: 0.96 (95%CI: 0.51-1.83)). The morbidity and mortality of NAC varied with the regimens used preoperatively. Of the 129 patients included in the analyzed studies, some acceptable toxicity was observed.
There is no definite evidence of the effectiveness of NAC in resectable gastric cancer, in terms of improvements in patient survival, in the trials we reviewed. Neoadjuvant chemotherapy should not be used routinely in clinical setting until further results from randomized clinical are available. Neoadjuvant chemotherapy of gastric cancer should be applied under the framework of clinical trials.