Nakamura T et al. – The results show that, regarding cell proliferation and apoptosis, the depressed type of intramucosal differentiated–type gastric cancer has high malignant potential in comparison to the elevated type.

• A total of 57 intramucosal differentiated gastric cancers were studied.
• Twenty samples were the elevated type and 37 were the depressed type.
• The tumor cells were analyzed by immunohistochemistry for Ki-67, Bcl-2, and Bax, and terminal deoxynucleotidyl transferase 2´-deoxyuridine, 5´-triphosphate (dUTP)-biotin nick end labeling was carried out to detect apoptotic cells.

• The Ki-67 labeling index (KI) was higher in the depressed type (median: 38.6) than in the elevated type (median: 21.2).
• Immunopositivity for Bax and the apoptosis index (AI) were lower in the depressed type (median AI: 0.20) than the elevated type (median AI: 1.05).
• The AI/KI was lower in the depressed type (median: 0.17) than in the elevated type (median: 5.57).
• The AI in the tumors with a Bcl-2-negative and Bax-positive pattern (median: 2.0) was higher than that in the tumors with a Bcl-2-positive and Bax-negative pattern (median: 0.2).