Radiotherapy in localized gastric cancer management: To be or not to be?

Abstract

e16511 Background: Gastric adenocarcinoma still have dismal outcome in spite of the progress made in systemic treatment in last 2 decades. In localized disease, treatment outcome still suboptimal, with up to 88% suffer from recurrence/metastasis. Hence, improvement in radical initial treatment is mandatory. Recent trials showed survival benefit of adding radiotherapy (preoperative or adjuvant) with favorable toxicity profile when using current advances radiation techniques. Methods: We retrospectively analyzed impact of radiotherapy in management of localized gastric cancer in Kuwait. 87 adult patients with newly diagnosed gastric cancers were treated and followed up at Kuwait Cancer Control Center (KCCC) between 2009-2015, 12 were excluded due to inoperability. 13 patients were excluded as they had early disease and underwent only surgery. Finally, 62 patients were submitted in study 48 patient received radiotherapy (RT group) as part of treatment (44 postoperative, 3 postoperative after induction Chemotherapy, 1 preoperative). 14 patients did not receive radiotherapy (NRT group); five received perioperative chemotherapy, nine received postoperative chemotherapy). Survival analysis was done using Kaplan-Meier, and comparison was done according to clinicopathological features. Results: The median age at diagnosis was 55 (range 25-70). Men represented 65.5%. Asian were 17 patients and Caucasian were 70 patients. 68.9% were nonsmoker while 31% were smoker. Median follow up was 45 months (1-89). 2 year Overall survival in the NRT group was 50% while in RT group was 79.1%. 3 year OAS was 42.8% and 64.5% in NRT group and RT group respectively. Median overall survival for NRT group was 82 months. While for the RT group median survival was not reached at time of analysis with p value (0.025). 2 year DFS in NRT group was 50% while in RT group was 66.6%. 3 year DFS was 42.8% and 54.1% in NRT group and RT group respectively. Median DFS not reached in both groups p value (0.04). On correlation of prognostic clinicopathological features with benefits of adding radiotherapy it was noticed that high grade, positive margins statistically benefit more from local radiotherapy and had better local control. Distal tumours behave badly whether received radiotherapy or not. Interestingly benefit of adding radiotherapy was not significantly affected by nodal status. Conclusions: Radiotherapy should be part of management in postoperative locally advanced gastric cancer especially with high grade tumours and positive margins. However still ongoing trials to clear the role of radiotherapy in preoperative setting.