PROGNOSTIC-SIGNIFICANCE OF APOPTOSIS RELATED PROTEINS BCL-2 AND BAX IN NODE-NEGATIVE BREAST-CANCER PATIENTS

In this immunohistochemical study we investigated the expression of Bc l-2 and Bar apoptosis related proteins in node-negative breast carcino mas. The results were con elated with the recurrence rate of the patie nts. In order to avoid the influence of the most important tumor progn ostic parameters Mie selected two groups of node negative breast ducta l carcinomas that were grade II according to Bloom and Richardson clas sification, had a diameter of 1-3 cm but differed in clinical outcome: 44 of the patients had a 10 year disease-free survival while 46 devel oped metastatic disease in the same period of time. Bcl-2 and to a les ser degree Bar expression were inversely related with distant metastas es (Pbcl-2 = 0.007, P-bax = 0.03). Combined analysis of Bax/Bcl-2 expr ession in relation to clinical outcome showed that the absence of both factors was more strongly associated with the development of distant metastases (P = 0.006, P-trend = 0.001). Our findings indicate that Bc l-2 and Bax apoptosis-related proteins are good indicators of prognosi s in node-negative breast cancer patients, and their combined absence, suggestive of serious deregulation of the apoptotic process, may cont ribute to the biologic aggressiveness of the tumors.