[Clinicopathologic features of gastric adenocarcinoma based on the revised Lauren's classification]

Objective: To compare the clinicopathologic features and prognosis of the subtypes in a consecutive series of gastric cancers (GC) patients basing on the revised Lauren's classification so as to better understand the biological behavior of GC. Methods: The surgically resected GC from Peking Union Medical College Hospital during 2003-2005 were reviewed for patients' age, gender, tumor size, location, Borrman classification, depth of invasion, lymph node metastasis, vascular invasion, and tumor growth pattern (Ming classification). Results: One hundred and sixty-six GC cases were enrolled and classified into four groups: intestinal GC (30, 18.1%), diffuse GC (56, 33.7%), solid GC (9, 5.4%), and mixed GC (71, 42.8%). Intestinal GC patients were older[ (63.2±11.3) years], with a male predominance, and were more frequently found in the antrum. Intestinal GC was the most common subtype for early GC, and tend to develop liver metastases. Diffuse GC patients were youngest [(52.2±12.7) years], with no gender difference, and were usually found in the antrum. Microscopically, diffuse GC were more likely infiltrative (51/56, 91.1%), and tended to metastasize by lymphatic pathway. Solid GC were usually large[ (6.4±2.2) cm], with a male predominance, and the most frequent site was the body/fundus. Solid GC were more likely to show expansile growth pattern with greater depth of invasion (8 of 9 cases were T3/4), but lower rate of lymphatic metastasis. Mixed GC also showed a male predominance, usually found in the antrum, and showed an infiltrative growth pattern (49/71, 69.0%). Though there was fewer T3/4 than solid and diffuse GC, mixed GC were more likely to show lymph nodes, vascular metastases and liver metastases (13/71, 18.3%). TNM staging, lymph nodes metastasis, lymphovascular invasion and revised Lauren's classification were four independent prognostic factors on multivariate analysis(P<0.05). The survival of patients with mixed GC were significantly worse than patients with other histological types. Conclusion: Revised Lauren's classification for GC has four distinct subgroups and can be used as independent prognostic factors.