Premalignant lesions in the contralateral ovary of women with unilateral ovarian carcinoma

Objective. A limited number of studies have looked at premalignant lesions of ovaries and the results are conflicting. Our goal is to identify, histologically and by immunohistochemistry, any features that may represent premalignant changes in the ovaries. Methods. Our cases included 29 patients with unilateral ovarian cancer. These were compared to 19 controls that had unilateral benign ovarian pathology and to 39 controls with bilateral normal ovaries. Tissue sections from the contralateral normal ovary were examined. Analysis of histological features and immunohistochemical staining for the apoptosis inhibitor Bcl-2, the proliferation marker Ki-67 and the tumor suppressor gene p53 was performed. Results. Epithelial stratification, nuclear atypia, and inclusion cysts were more often seen in the cases than in the two control groups. Epithelial stratification and nuclear atypia was statistically significantly more common among the cases than the normal controls. Inclusion cysts were present in more of the cases ( P = 0.017) and in higher numbers than in the normal controls. Bcl-2 overexpression was statistically more commonly seen in the cases with contralateral ovarian cancer (39%) than in the normal controls (15%), while it was present in 28% of cases with contralateral benign pathology. Conclusions. Epithelial alterations and Bcl-2 overexpression was seen in all three groups studied. However, the epithelial alterations and Bcl-2 overexpression was more commonly seen in the contralateral ovary of women with unilateral ovarian cancer. This suggests an association between these changes and ovarian cancer. Although it is tempting to label the above changes premalignant, women with the above changes are at possibly higher risk of developing ovarian cancer rather than having acquired an oncogenic change that would inevitably lead to ovarian cancer.