A cross-sectional study of immunohistochemical evaluation of surface epithelial ovarian tumors

Background: Ovarian cancer is one of the most common malignancies in female patients. In recent years, immunohistochemistry (IHC) has emerged as an important tool in the diagnosis of ovarian tumors. The study aimed to assess estrogen receptors (ERs), progesterone receptors (PRs), Her-2-neu, and Ki-67 by IHC in surface epithelial ovarian tumors and to correlate the findings with different variables. Materials and Methods: It was a cross-sectional study. Oophorectomy/salpingo-oophorectomy/cystectomy specimens were included in this study. IHC was done on 10% neutral buffer formalin-fixed paraffin-embedded tissue sections by using Dako FLEX Ready to use mouse monoclonal antibodies and DakoEnvisionTM FLEX/HRP detection reagent. Results: The study includes 81 cases of surface epithelial ovarian tumors (a benign serous tumor [20], a benign mucinous tumor [18], a borderline mucinous tumor [5], low-grade serous carcinoma [8], high-grade serous carcinoma [19], mucinous carcinoma [7], endometrioid carcinoma [2], borderline Brenner tumor [1], and malignant Brenner tumor [1]. ER had higher expression in malignant cases (51.33%) than in benign cases (15.8%). PR had higher expression in malignant tumors (54.05%) incomparable to benign (18.42%) and borderline tumors (16.66%). PR had higher expression in high grade. Expression of Her-2-neu positivity was found to be 29.7% out of the total 81 cases. Her-2-neu was found in 11 high-grade tumors among 31 malignant cases. CA-125 levels were significantly higher in malignant ovarian tumors (P = 0.0143). Proliferation activity was considered low if proliferation index (PI) 10%. The study showed high PI in malignant tumors. Conclusion: Expression of these marks in adjunct to H&E diagnosis may prove beneficial in differentiating benign, borderline, and malignant cases, in which a diagnosis of borderline cases based on sole H & E is doubtful.