Comparison of long-term oncologic outcomes between metastatic ovarian carcinoma originating from gastrointestinal organs and advanced mucinous ovarian carcinoma.

Background: Occasionally, ovarian tumors are found to have originated from non-ovarian organs as metastatic lesions since the ovary is a common site of metastasis from many cancers. The aim of the current study was to estimate the long-term oncologic outcome of patients with metastatic mucinous ovarian carcinoma (MmOC) in comparison with those with primary mucinous ovarian carcinoma (PmOC) at an advanced stage.
Materials and Methods: The data of one hundred and sixty-seven patients with mucinous ovarian cancer, including 91 patients with MmOC from the digestive organs and 76 patients with stage III-IV PmOC, were retrospectively analyzed. The prognostic significances of clinicopathologic factors were evaluated employing both uni- and multivariable analyses. Pathological slides were evaluated based on centralized pathological review.
Results: The median age of patients with PmOC and MmOC was 55 (18-81) and 51 years (30-82), respectively. With follow-up of a total of 167 patients, 145 patients (86.8%) developed recurrence. In addition, 122 patients (73.0%) died of the disease. Regardless of the residual tumor status, patients with PmOC did not a show a significantly poorer OS than those with MmOC. Furthermore, in a Cox multivariable hazard model, after adjustment for various clinicopathologic confounders, a gastric cancer (GC)-originated tumor and larger residual tumor were significant predictors of poorer OS [GC (vs. PmOC): HR (95% CI) 2.205 (1.303-3.654), P = 0.0036].
Conclusion: The oncologic outcome of patients with MmOC was extremely poor; however, it was almost the same as that of those with PmOC. We should recognize MmOC derived from gastric carcinoma as a highly aggressive malignancy.