Histological subtypes and distribution of ovarian epithelial carcinoma as seen in the department of pathology, Makerere University, college of health sciences, Kampala, Uganda

Abstract

Background Malignant ovarian neoplasm is the sixth most common malignancy among Ugandan women. Globally, ovarian epithelial carcinoma accounts for 90% of all malignant ovarian neoplasms. Routine microscopic examination alone can identify histological types of ovarian epithelial carcinoma that show distinct clinical behaviour and specific genetic features which have therapeutic as well as prognostic implications. In Uganda, histological subtyping of ovarian epithelial carcinoma is overlooked; hence their distribution remains unclear. Objectives The aim of this study was to describe the histological subtypes and distribution of ovarian epithelial carcinoma seen in the Department of Pathology, Makerere University College of Health Sciences (MakCHS). Methods This study was carried out in the Department of Pathology, MakCHS from February to May, 2012; through a cross sectional study on formalin fixed and paraffin wax embedded tissue blocks. Cases that had been histologically diagnosed as ovarian epithelial carcinoma between 2002- 2011 inclusive were retrieved from the tissue repository and their ages from the corresponding histology request forms. All retrieved archival tissue blocks were resectioned and stained with haematoxylin and eosin. The stained tissue sections mounted on glass slides were examined under light microscopy and subtyped using the modified (2009) World Health Organization morphological criteria. Results One hundred and nine cases of ovarian epithelial carcinoma with an age range of 23 to 80 years had a mean age of 49 years. Of these, 44% were below 45 years of age and 87% were between 30 to 69 years of age. The histological subtypes of ovarian epithelial carcinoma seen were as follows: high grade serous─74.3%, low grade serous─12.8%, mucinous─4.6%, Brenner’s/Transitional─3.7%, endometrioid─1.8%, clear cell─1.8% and mixed─0.9%. The majority (96%) of high grade serous carcinomas showed a highly cellular, stratified epithelium with irregular slit like spaces as well as marked nuclear pleomorphism. Conclusion The age specific incidence of ovarian epithelial carcinoma rises precipitously from approximately 20 to 70 years and subsequently declines. More than one third of the cases were in reproductive age group. Ovarian epithelial carcinoma is extremely rare in very young women and children. The high grade serous carcinoma comprising of a highly stratified epithelium with fenestrated appearance and slit like spaces is the most common histological subtype of ovarian epithelial carcinoma seen in this study.