Prognostic significance of subclassification of pT2 gastric cancer: a retrospective study of 847 patients

Abstract

Purpose: To investigate the prognostic significance of subclassification of pT2 gastric cancers according to the nodal status.

Methods: Clinicopathological characteristics and prognostic outcomes of 847 gastric cancer patients who received a gastrectomy between 1985 and 2003 were retrospectively evaluated based on the subclassification of pT2 stage (i.e. pT2a and pT2b).

Results: Of the patients, 244 and 603 had pT2a and pT2b stage cancers, respectively. Patients with pT2a cancers had a significantly longer disease-specific 5-year survival rate than those with pT2b cancers (P<0.001). The prognosis was significantly better in patients with pT2a cancers than in patients with pT2b cancers at pN0, pN1 and pN2 (P=0.036, 0.021, and 0.019 respectively), but not pN3 stages (P=0.775). Multivariate analysis identified age, tumor location, pT stages, pN stages, and adjuvant chemotherapy as independent prognostic factors for pT2 gastric cancers. The survival rates were similar between pT2aN1 (stage II) and pT2bN0 (stage IB) cancers (P=0.604), and between pT2aN2 (stage IIIA) and pT2bN1 (stage II) cancers (P=0.936).

Conclusions: Subclassification of pT2 gastric cancers into pT2a or pT2b is of prominent prognostic significance, and thus it is recommended that the current stage grouping conventions include subclassification of pT2, in order to more accurately predict the prognosis of patients.