Comparison of first-line chemotherapy regimens for ovarian carcinosarcoma: a single institution case series and review of the literature.

BACKGROUND: The optimal first-line chemotherapy for ovarian carcinosarcoma has not yet been determined. We therefore sought to determine the progression-free survival (PFS) and overall survival (OS) for patients with ovarian carcinosarcoma treated at our institution with different first-line chemotherapy regimens.

METHODS: This single-institution, retrospective analysis included all patients with ovarian or primary peritoneal carcinosarcoma diagnosed from September 1996 to July 2017. Kaplan Meier analysis with a log-rank Mantel-Cox test was used to compare PFS and OS between treatment groups, and a p-value of < 0.05 was considered statistically significant.

RESULTS: Thirty-one patients met inclusion criteria: two patients were stage IC, 5 were stage II, 21 were stage III, and 3 were stage IV. The median PFS and OS for all stages was 9.3 and 19.7 months respectively. Fifteen patients (48%) received carboplatin/paclitaxel as first therapy, 7 (23%) received ifosfamide/paclitaxel, 6 (19%) received a different regimen, and 3 (10%) did not receive chemotherapy. Patients treated with carboplatin/paclitaxel had a statistically significant longer PFS when compared to those receiving ifosfamide/paclitaxel (17.8 vs. 8.0 months, p = 0.025). OS was similar between all comparisons.

CONCLUSIONS: In summary, in our cohort of ovarian carcinosarcoma patients, median PFS is longer in patients treated with carboplatin/paclitaxel compared to ifosfamide/paclitaxel. Overall survival was similar for all treatment groups, potentially due to subsequent treatment crossover. Given the rarity and aggressive nature of this tumor, further study into optimal first-line chemotherapy is warranted.