Clinical Significance of Recurrence Risk Score for Conversion Surgery in Patients With Advanced Gastric Cancer

BACKGROUND/AIM: To develop a recurrence risk score for determining the clinical indication for adjuvant chemotherapy in patients with initially unresectable advanced gastric cancer who underwent conversion surgery after chemotherapy. PATIENTS AND METHODS: A total of 65 patients with stage IV gastric cancer who underwent conversion surgery after chemotherapy were retrospectively enrolled. We established a risk score based on clinicopathological factors related to recurrence after conversion surgery. RESULTS: Out of 65 patients, 40 (62%) had recurrence after conversion surgery. The 5-year overall survival rates in patients with and without recurrence were 14.4% and 87.1%, respectively (p<0.01). Multivariate logistic regression analysis identified the depth of tumor invasion (pT2-4) and histological tumor response (grade 0-1a) as an independent risk factor for disease recurrence (p=0.033 and p=0.048, respectively). A scoring system determined by these two factors was created; total score ranged from 0 to 2 points, and patients were categorized into three groups (scores of 0 vs. 1 vs. 2 points). This scoring system showed that 12 (18%), 15 (23%), and 38 (58%) patients had recurrence risk scores of 0, 1, and 2 points, respectively. There was a close relationship between a high score and the presence of tumor recurrence (p<0.01). Moreover, our model system had a high sensitivity for the prediction of recurrence, compared with the pathological stage. CONCLUSION: Recurrence risk score is a promising tool for assessing the need for adjuvant chemotherapy in patients with initially unresectable advanced gastric cancer after conversion surgery.