Post-recurrence survival in patients with stage III gastric cancer who received adjuvant chemotherapy; post-hoc analysis of the JACCRO GC-07 study

Background

As adjuvant chemotherapy for stage III gastric cancer, the phase III (JACCRO GC-07) trial showed that docetaxel plus S-1 (DS) was superior to S-1 in terms of recurrence-free and overall survival. However, whether adding docetaxel to S-1 in the adjuvant setting affects survival after recurrence remains unclear. The optimal treatment strategy for patients who develop recurrence during or after DS has also been controversial.

Methods

We used results from JACCRO GC-07 to investigate post-recurrence survival (PRS) in patients who developed recurrence during or after completing adjuvant chemotherapy. PRS was compared between adjuvant groups and among post-recurrence chemotherapeutic regimens.

Results

During 5 years of follow-up after surgery, 161 of 441 patients in the DS group and 216 of 452 patients in the S-1 group developed recurrence, with median PRS of 12.6 and 11.4 months, respectively (hazard ratio [HR] 0.98, 95 % confidence interval [CI] 0.79–1.22; p = 0.84). Among patients with recurrence, 115 patients in the DS group and 165 patients in the S-1 group received chemotherapy, and median PRS was 14.5 and 13.7 months, respectively (HR 1.04, 95 %CI 0.81–1.34; p = 0.76). Platinum-based chemotherapy resulted in longer PRS than non-platinum chemotherapy, regardless of the adjuvant chemotherapeutic regimen or time of recurrence.

Conclusions

PRS was similar between patients who received adjuvant chemotherapy with DS or with S-1 alone. PRS was also similar between groups of patients who received chemotherapy after recurrence. Platinum-based chemotherapy might be the optimal treatment for patients who develop recurrence after completing adjuvant DS, regardless of the time of recurrence.