Clinicopathological and Immunohistochemical Study of High Grade Serous Ovarian Carcinoma

Abstract

Background: High grade serous ovarian carcinoma has a heterogenous morphology and marked genomic instability with aggressive behavior and poor overall prognosis. A molecular classification of HGSOC demonstrated 4 subtypes; C1, C2, C4 & C5 as a trial to correlate this molecular classification with patient prognosis. A correlation between these molecular subtypes, clinical data, histopathological criteria and immunohistochemical features needed to be established aiming at individualization of the treatment of each patient to achieve the best outcome. Aim: Investigating for a correlation between the histopathological classification of high grade serous ovarian carcinoma (HGSOC), clinicopathological parameters, and immunohistochemistry. Methods: Eighty five cases of high grade serous ovarian carcinoma were revised for their clinical data regarding their age, pathological staging, CA 125 levels, ascites, and chemotherapy regimen taken. The cases classified into four groups. Paraffin-embedded HGSOC specimens were re-cut at 5 microns thickness sections and stained with haematoxylin and eosin stain and examined for the different histopathological criteria. The tissue sections were also stained immunohistochemically with antibodies against Ki67, CD8, E cadherin, Vimentin, ER & PR. Results: HGSOC could be classified into 4 groups (mesenchymal, immunoreactive, Proliferative & differentiated type either with SET features or papillary features). Ki 67 & CD8 had a strong significant correlation with the proliferative subtype & immunoreative subtype respectively (P< 0.001). Low PR expression was also correlated with advanced stage disease in cases underwent 1ry debulking surgery (P=0.03). in cases received neoadjuvant treatment, differentiated subtype with SET features showed a statistically significant correlation with high CD8 expression.