Own experience of adjuvant chemotherapy in operable gastric cancer (retrospective analysis)

Introduction. Stomach cancer (SC) is the second leading cause of death from cancer in the world. Surgical removal is still cornerstone of treatment for SC. The question on the necessity of adjuvant chemotherapy remains unclear. Objective. To analyze retrospectively the effectiveness of adjuvant chemotherapy for resectable gastric cancer in Arkhangelsk Clinical Cancer Center during the period from 2006 to 2010. Materials and methods. The overall survival (OS) was retrospectively assessed in patients with resectable stage II-III SC, receiving or not receiving adjuvant chemotherapy. Initial characteristics’ distribution was compared using the chi-square method, while the median OS - using log-rank method. Cox regression was applied for evaluation of factors influencing OS. Results. One hundred and forty six and 74 patients were selected to surgery alone and combined treatment groups, respectively. At one, 3 and 5 years 84% (95% confidence interval (CI), 78-90%) 69% (95% CI, 64-74%) and 63% (95% CI, 56-69%) patients were alive in the surgical group, while in combined treatment group - 92% (95% CI, 85-98%), 62% (95% CI, 49-74%) and 47% (95% CI, 35-59%) patients respectively. The median follow-up for all patients was 54 (range 13-100) months. Median survival in the adjuvant chemotherapy group was 53 (95% CI 28-78) months, in the surgical group was not reached. Differences in survival between the groups were not statistically significant (χ 2 = 1,2, p = 0.277). In multivariate analysis the adjuvant chemotherapy did not improve disease-free and overall survival. The only prognostic factor, significantly affecting OS was stage, HR 0.41 (95% CI 0,24-0,70). There was a trend towards improved prognosis for patients with platinum-containing adjuvant chemotherapy, HR 0.25 (95% CI 0,03-1,93). Conclusion. In a retrospective analysis adjuvant 5-fluorouracil both in monotherapy and in non-Platinum combinations did not improve OS of patients with resectable SC. A trend towards increased survival after platinum-containing adjuvant chemotherapy is registered. These results require confirmation in a randomized trial.