Grading of the ovarian serous cystadencarcinomas, and its correlation with BRCA1 and p53 immunoreactivity

Abstract

Objective: Ovarian cancer is a gynecological malignancy with the higest mortality. The surface epithelial tumors of the ovary are the most common cancer types. The purpose of this study was to grade the ovarian serous cystadenocarcinomas and to evaluate BRCA1 and p53 proteins immunohistochemically. Material and Methods: Fifty-eight cases diagnosed as serous cystadenocarcinomas of the ovary were selected for this study. The cases were graded according to two-tier grading system, FIGO and Shimizu-Silverberg grading system and the results were compared. The BRCA1 and p53 proteins were studied immunohistochemically. Results: The cases were distributed as follows: according to the two-tier grading system low grade 12 (21%) cases and high grade 46 (79%) cases; according to the FIGO grading system grade 19 (16%) cases, grade B 29 (50%) cases, and grade 11120 (34%) cases and according to the Shimizu-Silverberg grading system grade 111 (19%) cases, grade II 29 (50%) cases, and grade 11118 (31%) cases. Positive p53 staining was detected in 57% (33/58) and BRCA1 was detected in 67% (39/58) of the cases. The relationship between p53 and BRCA1 proteins and histopathologic grade was analyzed. High grade ovarian serous carcinomas had a higher rate of p53 expression (65%) compared to low grade (25%) tumors. BRCA1 immunstaining was detected in 92% (11/12) of low grade and 61% (28/46) of high grade tumors according to two-tier grading system. Conclusion: There is a good correlation between the two-tier grading system and the FIGO and the Shimizu-Silverberg grading systems. In addition, the application of the two-tier grading system for ovarian serous carcinomas is easy because this system is based on easily understood two criteria and includes two categories (low grade, high grade). In contrast to p53, high grade tumors had a lower rate of BRCA1 expression (61%) compared to low grade (92%) tumors. In high-grade carcinomas, no statistical correlation was present between the p53 and BRCA1 positivity (p= 0.666).