Flow Cytometric Analysis of Apoptosis in Colorectal Adenomas and Carcinomas

Osamu Kimura, Nariyuki Yamane, Kenji Sugamura, Masato Makino, Michio Maeta, Nobuaki Kaibara

First Department of Surgery, Faculty of Medicine, Tottori University

We assessed the occurrence of apoptotic cell death in 24 colorectal adenomas, 69 colorectal carcinomas and 37 metastatic lesions, which included 21 of the liver and 16 of lymph nodes, in order to investigate the possible relation between apoptosis and clinicopathological features and to evaluate apoptosis as a possible prognostic factor. The apoptotic index (AI) was calculated by flowcytometry using terminal-deoxynucletidyl-transferase-mediated dUTP-biotin nick end labeling. The median values of AI were 27.0 in normal mucosas, 28.2 in adenomas and 15.2 in colorectal carcinomas. The AI was significantly lower in colorectal carcinomas than in normal mucosas and adenomas. Apoptosis of colorectal carcinomas was less frequently observed in tumors with higher malignant potential, such as tumors at advanced stages and with venous and lymphatic invasion. Moreover, the patients with a low AI had significantly poorer survival than those with a high AI. In comparing apoptosis between primary and metastatic lesions, AI was significantly lower in the latter. These results suggest that less apoptosis might result in greater progression of colorectal carcinomas and that the rate of apoptosis might be an indicator of the degeee of malignancy.

Key words
apoptosis of colorectal carcinoma, apoptosis of adenoma, apoptosis of metastatic lesion, apoptosis and prognosis of colorectal carcinoma

Reprint requests
Osamu Kimura First Department of Surgery, Faculty of Medicine, Tottori University
36-1 Nishimachi, Yonago, 683 JAPAN

Accepted
January 8, 1997

To read the PDF file you will need Abobe Reader installed on your computer.