Vascular endothelial growth factor expression in serous ovarian carcinoma: relationship with topoisomerase II alpha and prognosis.

OBJECTIVE: This study investigated the expression of vascular endothelial growth factor (VEGF) and topoisomerase II alpha (TPII alpha) in a cohort of serous ovarian carcinomas by immunohistochemistry with regard to outcome and clinicopathologic variables.
METHODS: Formalin-fixed, paraffin-embedded archival tissue sections of 10 benign serous cystadenomas and 41 serous ovarian carcinomas were immunostained with antibodies to VEGF and TPII alpha. Immunostaining for VEGF was scored with regard to quantity and intensity of positively stained cells as weak, focal strong, and diffuse strong. TPII alpha labeling indices (LI) were quantitated as the percentage of positively stained nuclei in 1000 tumor cells.
RESULTS: VEGF expression was weak or negative in serous cystadenomas. In contrast, focal or diffuse strong immunostaining was observed in 21 cases (51%) of serous carcinomas. VEGF immunoreactivity was positively related with TPII alpha LI (P = 0.0055), adverse outcome (P = 0.0052), high International Federation of Gynecology and Obstetrics (FIGO) stage (P = 0.0158), and high tumor grade (P = 0.0303). TPII alpha LI increased with FIGO stage (P = 0.0076) as well as tumor grade (P = 0.0034) and indicated poor prognosis (P = 0.0182).
CONCLUSIONS: VEGF immunoreactivity is related with TPII alpha LI and prognostically relevant. Expression of VEGF protein and TPII alpha may serve as markers of aggressive tumor behavior in serous adenocarcinomas.