Histomorphological Spectrum of Ovarian Tumors with Immunohistochemical Analysis of Poorly or Undifferentiated Malignancies

Background: Ovarian cancer has the worst prognosis and highest case fatality rate among all gynecological malignancies. Differential diagnosis remains a major problem in histopathology of ovarian tumors especially for poorly differentiated or undifferentiated malignancies. This study was conducted to determine the frequency of morphologic spectrum of ovarian tumors and the role of immunohistochemistry in definite histogenesis of poorly differentiated or undifferentiated ovarian malignancies. Material & Methods: This descriptive study was conducted at Histopathology section of Dow Diagnostic Reference and Research Laboratory at Dow University of Health Sciences, during a period of 2 years from 2008 to 2010. The study material included 123 consecutive samples of ovarian tumors. Inclusion criteria were pretreatment cases with sufficient tumor material. In addition we also included 20 cases/blocks of poorly or undifferentiated malignancies submitted for immunohistochemistry. Results: The mean age of study group was 33.7±13 years (range 5-72 years). Out of 123 cases, 93(75.6%) were benign, 4(3.3%) borderline and 26(21.1%) malignant. Amongst benign tumors, serous cystadenoma was the most frequent subtype, while for the malignant tumors serous cystadenocarcinoma was the commonest. Regarding the analysis of 20 undifferentiated or poorly differentiated tumors, sex cord tumors with 7 cases were found as the commonest malignancy. Conclusion: Malignant germ cell tumors appear to be more common in our population. Immunohistochemical analysis is helpful in the proper diagnosis of undifferentiated or poorly differentiated tumors.