ROLE OF IMMUNOHISTOCHEMISTRY IN OVARIAN TUMORS

BACKGROUND: Ovarian tumors are characterized by marked heterogeneity in their clinical presentation, so an accurate histopathological diagnosis is needed. Immunohistochemistry is helpful in vast number of cases where the morphology and clinical data alone do not allow definite diagnosis of tumor present in tissue sections. AIMS: 1. To evaluate the role of immune- histochemistry in classification and histogenesis of ovarian tumours and in resolving diagnostic dilemma in closely mimicking and poorly differentiated tumours. 2. To evaluate the role of immunohistochemistry in ovarian tumours and to differentiate primary from metastatic tumours. MATERIALS AND METHODS: 80 operated cases of ovarian tumours over a period of one and half year (January 2008 to September 2010) were studied. Paraffin blocks of various ovarian tumours for relevant immunostains were subjected for automated immunostaining. Total 52 immunostains were included in the study. RESULTS: Out of the 80 cases of ovarian tumours, benign ovarian lesions were more common (75%) than malignant lesions (25%). Serous cystadenoma was the commonest benign tumor (45%). Overall surface epithelial carcinomas were responsible for 70% of all malignant lesions among which serous cyst adenocarcinoma was most common (45%). 88.8% cases of serous carcinomas showed diffuse positivity for CK7, 60% showed positivity for CA125 and 100% were negative for CK20. 100% cases of mucinous carcinoma showed positivity for CK7, 66.66% showed positivity for CEA and 100% were negative for CA125. ER and PR showed nuclear positivity in both cases (100%) of endometrioid carcinoma. Dysgerminoma showed positivity for placental alkaline phosphatase (PLAP). Yolk sac tumor was positive for alpha-feto protein (AFP). Embryonal carcinoma was positive for CD30. Granulosa cell tumor was positive for Calretinin and Inhibin and negative for AFP. CONCLUSION: Thus IHC is helpful in confirming the histological diagnosis, to know the histogenesis of ovarian tumours. It is particularly helpful in resolving the diagnostic dilemma in closely mimicking and poorly differentiated ovarian tumours. IHC is also helpful in differentiating primary ovarian tumours from metastatic tumours. This differentiation is important for both