Fifteen RCTs (3,162 women) were included. Ten of these RCTs were included in the meta-analysis.
Radiotherapy versus no treatment: the one identified RCT did not report results for each treatment arm.
Chemotherapy versus radiotherapy (5 RCTs, 862 women): in all these RCTs, the treatment groups were similar at baseline with respect to prognostic factors. There was no significant difference in overall survival or disease-free survival between chemotherapy and radiotherapy. The HR was 0.85 (95% CI: 0.62, 1.17) for overall survival and 0.94 (95% CI: 0.56, 1.59) for disease-free survival. Significant heterogeneity was found. A subgroup analysis showed no significant difference between chemotherapy and whole abdomen radiotherapy, between chemotherapy and P32 radiotherapy, or between platinum-based chemotherapy and P32 radiotherapy (the results were reported).
Chemotherapy plus radiotherapy versus radiotherapy alone (2 RCTs, 242 women): the studies compared whole abdominal radiotherapy with pelvic radiotherapy plus chemotherapy. In neither study were the treatment groups similar at baseline with respect to prognostic factors. Neither study presented extractable quantitative data. The individual studies showed no significant difference in survival between the treatments.
Chemotherapy versus no treatment (5 RCTs, 1234 women): 75% of the patients came from 2 RCTs. The RCTs were all of a good quality. The meta-analysis showed that chemotherapy significantly improved overall survival and disease-free survival. The HR was 0.71 (95% CI: 0.63, 0.80) for overall survival and 0.68 (95% CI: 0.59, 0.79) for disease-free survival.
The analysis was repeated after removing the one RCT that did not use a platinum-based chemotherapy regimen. Neither the results for overall survival nor disease-free survival were altered (the results were reported).