Objective: The purpose of this study was to define the incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE) in patients with clear cell carcinoma (CCC) of the ovary and to investigate the prognostic factors in such patients.
Methods: Between January 1987 and December 2003, 641 women with primary invasive epithelial ovarian cancer underwent treatment at the Royal Hospital for Women in Sydney, Australia. Sixty-six patients (10.3%) with CCC were identified from the data bank, and their data were compared with a matched-control group of 132 patients with non-clear cell epithelial ovarian carcinoma.
Results: A thromboembolic event (DVT or PE) was noted in 27.3% of patients with CCC, compared to 6.8% of patients with other epithelial ovarian cancers. PE was detected in 13.6% and 3.8% of patients, respectively. In patients with CCC, DVT was frequently observed before operation or at the time of recurrence. In a multivariate analysis of patients matched for age and stage, the occurrence of a DVT or the presence of endometriosis was significant predictors of clear cell histology. Within the clear cell group, no particular risk factor for DVT could be identified. Metastases of 50 mm or greater in diameter, ascites of 1000 ml or more, advanced FIGO stage, and the occurrence of DVT were poor prognostic factors for CCC in univariate analysis, but in a multivariate Cox regression analysis, only FIGO stage and occurrence of DVT remained significant.
Conclusion: The incidence of venous thromboembolic events was found to be significantly higher in patients with CCC when compared to patients with other epithelial ovarian cancers.