Prognostic value of histological type in stage IV ovarian carcinoma: a retrospective analysis of 223 patients.

Background: Patients with FIGO stage IV epithelial ovarian carcinoma have a poor but non-uniform prognosis. This study aimed to compare the survival of patients with serous or endometrioid tumours (S/E) and clear cell or mucinous tumours (non-S/E).
Methods: Data for 223 patients who underwent surgery between 1987 and 2010 and were diagnosed by centralized pathology review and were retrospectively analysed. The patients included 169 with S/E tumours and 54 with non-S/E tumours.
Results: The median overall survivals (OSs) of the S/E and non-S/E groups were 3.1 and 0.9 years, respectively (P<0.001). Six patients (2.7%), all with non-S/E tumours, died within 6 weeks after the initial surgery. Multivariate OS analysis revealed that performance status, residual tumor, metastatic sites, no debulking surgery, and non-S/E tumours were independent poor prognostic factors. For patients with non-S/E tumours, prognosis was more favourable for single-organ metastasis, except for liver or distant lymph nodes, no residual tumor, and resection of metastasis (median OS: 4.1, 4.6, and 2.6 years, respectively).
Conclusions: In stage IV ovarian carcinoma, non-S/E tumours are associated with a significantly poorer prognosis and higher rates of early mortality compared to S/E tumours. Therefore, careful management and development of new strategies are required.