Bcl-2 Expression in Endometrial Hyperplasia and Carcinoma

Kim, Jong Hyeok; Koh, Chang Won; Huh, Joor Yung; Kim, Bong Hee; Kong, Hun Sik; Na, Jun Hee; Kim, Yong Nam; Kim, Young Tak; Nam, Joo Hyun

Abstract

PURPOSE
To speculate the role of bcl-2 protooncogene in endometrial carcinogenesis by determination of the expression of bcl-2 in endometrial hyperplasia and carcinoma.
MATERIALS AND METHODS
We studied bcl-2 expression by an immunohistochemical method in the paraffin-embedded blocks of 78 patients with endometrial hyperplasia, 64 with simple hyperpasia, 9 with complex hyperplasia and 5 with atypical hyperplasia respectively, and 33 endometrial carcinoma treated at Asan Medical Center from June, 1989 to May, 1997. Intensity of bcl-2 staining was scored on a scale of 0 to 4, calibrated by comparison with stromal lymphocytes, which always received a score of 4.
RESULTS
The results of this study showed that bcl-2 was relatively highly expressed in simple (n= 64), complex (n=9) and atypical hyperplasias (n=5) with mean staining scores of 2.95+/-1.09 (Mean+Standard Deviation), 2.78+/-1.20 and 3.60+/-0.89 respectively, which showed no difference among histologic types. In endometrial carcinoma, the expression of bcl-2 was significantly down regulated (mean score=1.76+/-1.35) compared with that of hyperplasia, and did not conelate with FIGO surgical stage. However, grade III tumor showed significantly lower expression that grade I or II tumor.
CONCLUSION
Bcl-2 expression is down regulated in endometrial carcinoma than endo- metrial hyperplasia, and correlates with tumor grade, which suggest that bcl-2 expression might be the result of carcinogenesis or bcl-2 plays only an adjunctive role in the endometrial carcinogenesis.