Kinetic patterns in advanced gastric cancer as related to histotype and tumor extension

Kinetic patterns of advanced gastric cancers were analyzed for comparison between intestinal- and diffuse-types by using the mean values of mitotic index (MI), apoptotic index (AI), the sum of the two [i.e., the turnover index (TI)] and growth index (GI), and the values of the same parameters in the three layers (upper, intermediate, lower) in which cancers were subdivided from surface to depth. Site and extent of tumors, lymph node invasion, and p53 and PCNA expression were not different between the two histotypes; tumor cell dissociation (TCD) was higher in diffuse-type cancers. Mean MI, AI, TI, and GI were not different between the two histotypes, while MI, AI, TI, and GI were higher in the upper layer of intestinal-type cancers than in that of diffuse-type. MI and GI decreased while AI increased from upper to deeper layers in intestinal-type tumors; MI, AI, and TI increase from upper to lower layers in diffuse-type tumors. In intestinal-type cancers, but not in diffuse cases, TI and GI were higher in the T2 group than in T3. This different behavior between the two histotypes is discussed.