Discussion of modifying stage IV gastric cancer based on Borrmann classification

This study aims to investigate the prognostic significance of reclassification of stage IV gastric cancers in conjunction with Borrmann type. A total of 1,673 gastric cancer patients who received a gastrectomy between 1980 and 2003 were retrospectively evaluated. Of the patients, 244 (14.58 %), 344 (20.56 %), 589 (35.21 %), and 496 (29.65 %) had stage I, II, III, and IV cancers, respectively. After Cox regression analysis, Borrmann type was identified to be the independent prognostic factor in stage IV gastric cancer. The disease-specific postoperative survival of patients with Borrmann I, II, and III tumors was clearly distinguished by TNM classification system (P < 0.05), while it failed to classify Borrmann IV tumors (P = 0.147). Interestingly, the disease-specific postoperative survival of stage IV patients with Borrmann IV tumors (group 1) was significantly poor than the cases with stage IV but not Borrmann IV tumors (group 2), as well as the patients with Borrmann IV while not included in stage IV tumors (group 3) (P = 0.022 and P = 0.000, respectively). Meanwhile, the disease-specific postoperative survival was not observed as significantly different between group 2 and group 3 (P = 0.063); furthermore, group 2 + 3 had a better prognosis than group 1 (introduced stage IVa vs. stage IVb; P = 0.006). Reclassification of stage IV through combining the present TNM classification system with Borrmann type may more accurately predict the prognosis of patients.