Survival and prognostic factors in patients with recurrent low-grade epithelial ovarian cancer: An analysis of five prospective phase II/III trials of NOGGO metadata base

Objective. Low-grade epithelial ovarian cancers (EOC), constitute the minority among all epithelial cancers. Our study objective was to focus on low-grade recurrent EOC and compare the survival with high-grade disease, as well as in regard to "platinum-sensitive" and "-resistant" recurrences according to platinum-free interval. Methods. This is an exploratory analysis within the North-Eastern German Society of Gynecological Oncology (NOGGO) database including five randomized phase II/III trials comparing different chemotherapy regimens in recurrent EOC. We conducted survival analyses and cox-proportional regression models. Results. Out of 1050 patients having the first recurrence, 42 (4%) patients had low-grade and 1008 (96%) patients had high-grade disease. In the subgroup of platinum-sensitive recurrences, progression-free survival (PFS) (8.7 m vs 9.7 m, p = 0.7) and overall survival (OS) (23.9 m vs 24.8 m, p = 0.9) did not differ between low-grade and high-grade diseases. In platinum-resistant recurrences, patients with low-grade ovarian cancer had significantly better PFS (7.6 m vs 3.6 m, p = 0.03) and OS (41.9 m vs 9.5 m, p = 0.002) in comparison to those with high-grade cancer. At low-grade EOC, there were no significant PFS (p = 0.91) and OS (p = 025) differences between platinum-sensitive and -resistant recurrences. Patients with low-grade non-serous histology had lower PFS with compared to those with low-grade serous histology (p = 0.004). At cox regression analysis presence of ascites and residual disease after secondary cytoreductive surgery were independently associated with poor PFS within low-grade recurrent EOC. Conclusion. Our study indicates, platinum-free interval does not have any prognostic significance at recurrent low-grade EOC and non-serous histology is associated with poorer outcome in recurrence. Secondary surgical cytoreduction to no-gross residual disease and ascites are independently associated with disease progression. (C) 2019 Published by Elsevier Inc.