An updated meta-analysis of adjuvant chemotherapy after curative resection for gastric cancer

Abstract 

Objectives

To investigate whether and how much gastric cancer patients after curative resection could benefit from chemotherapy.

Patients and methods

Meta-analysis was conducted with all the qualified clinical randomized trials which compared adjuvant chemotherapy with surgery alone. The database includes MEDLINE, EMBase and CBM disc, and the censor data were up to November 2007. Primary outcomes were relative risk (RR) on death and disease-free survival (DFS); secondary outcomes include RR of adverse reactions of the two arms. Sub-group analysis and sensitivity analysis were also performed. All the calculations and statistical tests were done with the RevMan 4.2.8 software.

Results

Finally, 23 trials which included 4919 patients (2441 in the adjuvant chemotherapy arm, 2478 in the observation arm) achieved all the criteria. Among them, 19 studies reported the survival rate at the end of follow-up, 60.6% alive among 2286 patients in the adjuvant chemotherapy arm, 53.4% alive among 2313 patients in the observation arm, with the RR on death of 0.85 (95%CI: 0.80–0.90). Eight studies reported the DFS, and the observation arm had a shorter DFS (RR: 0.88, 95%CI: 0.77–0.99). Grade 3/4 of myelosuppression and GI toxicity occurred more frequently in the treatment arm. Nine studies reported the recurrence rate and suggested that the treatment arm had a lower recurrence rate (RR: 0.78, 95%CI: 0.71∼0.86).

Conclusions

Statistically, adjuvant chemotherapy could improve the survival rate and disease-free survival rate in gastric cancer after curative resection and reduce the relapse rate. However, the clinical benefits of adjuvant chemotherapy still need to be improved. Additionally, post-operative chemotherapy could be tolerated.

Keywords: Gastric cancer, Adjuvant chemotherapy, Randomized controlled clinical trial, Meta-analysis