Prognostic value of subclassification of T2 tumours in patients with gastric cancer.

Background: This study was designed to evaluate the prognostic value of tumour stage T2 subcategorization (T2a and T2b) in patients with gastric carcinoma. Methods: Clinicopathological details of a prospective series of patients who had radical resection of gastric adenocarcinoma in a single institution were analysed. Univariable and multivariable survival analyses were performed with the log rank test and Cox's model respectively. Results: Of 373 evaluable patients, 49 (13.1 per cent) had a T2a and 143 (38.3 per cent) a T2b tumour. At a median follow-up of 35.5 months, the 5-year overall survival rate was 73 and 31.1 percent for patients with T2a and T2b lesions respectively (P < 0.001). On multivariable analysis, T stage remained an independent prognostic factor. Compared with T1a, the mortality risk for patients with T1b (hazard ratio (HR) 1.00; P = 0.992) and T2a (HR 0.97; P = 0.916) tumours was similar; by contrast, the risk of death associated with T2b (HR 1.81; P = 0.031) and T3 (HR 1.89; P = 0.038) lesions was significantly greater than for T1a tumours. Conclusion: Subclassification of T2 tumours should be undertaken routinely in order to stratify patients with gastric cancer more accurately in terms of their mortality risk.