544P Feasibility of two different first-line carboplatin plus paclitaxel regimens in elderly women with ovarian cancer: A retrospective study

Abstract

The EWOC-1 trial compared single-agent Carboplatin (C) to two Carboplatin-Paclitaxel (CP) regimens (weekly and standard every-3-weeks (sCP)) in vulnerable elderly patients with advanced epithelial ovarian cancer (OC). This study was terminated prematurely because of significantly worse progression-free (PFS) and overall survival (OS) outcomes in the C group. Both CP regimens were equivalent in terms of feasibility and efficacy. However, treatment adverse effects were less frequent with the sCP than weekly CP. This study aims to compare the feasibility of two CP regimens - sCP and fractionated regimen (fCP) - in elderly patients in our institution. This retrospective study enrolled patients ≥70 years with OC who received a first-line sCP regimen: C AUC4-5 + Paclitaxel (P) 175 mg/m2 d1q3week regimen, or fCP : C AUC4-5 d1q3week + P 80mg/m2 d1-d8 q3week, between 2015 and 2020. Primary endpoint was treatment feasibility according to the EWOC-1 standard. Secondary endpoints were investigator assessed PFS, OS and selected adverse events (AE). A total of 74 patients were analyzed. The median age was 76 years. Non-high-grade-serous histological types were more frequent in the fCP group (17%) than in the sCP group (5%). The feasibility endpoint was met in 30 of 38 (79%) and 21 of 36 (58%) patients in the sCP and fCP groups, respectively (P = 0.079). After the exclusion of non-high-grade-serous histological types, the feasibility endpoint was met in 29 of 37 patients (78%) in the sCP group and 21 of 30 patients (70%) in the fCP group (P = 0.547). The median PFS was 35.2 months (95% confidence interval [CI], 22.7 to NA) with fCP and 58 months (95% CI, 37.9 to NA) with sCP (P = 0.05). The median OS was not reached with sCP (95% CI, 54.7 to NA) versus 71 months with fCP (95% CI, 44 to NA; P = 0.40). Peripheral sensory neuropathy of grade 2 or 3 were reported in 11% of the patients in the fCP group as compared with 42% of those in the sCP group. Anemia of grade 3 or 4 occurred more frequently in the fCP regimen (28%) than the sCP regimen (5%). These results suggest that both CP regimens (standard or fractionated) are equivalent in terms of feasibility in elderly patients with OC.