Weekly Carboplatin and Paclitaxel: A Retrospective Comparison with the Three-Weekly Schedule in First-Line Treatment of Ovarian Cancer

Background: Conventional first-line combination therapy for ovarian cancer comprises 6 cycles of adjuvant or neoadjuvant carboplatin (AUC5-6) with paclitaxel (175 mg/m² ) every 3 weeks (PC-3W). Weekly scheduling of paclitaxel may maximize its antiangiogenic effect and reduce adverse effects. We compared the efficacy and safety of PC-3W with a modified protocol of weekly paclitaxel 80 mg/m² and weekly carboplatin AUC2 administered on days 1, 8, and 15 in a 28-day cycle (i.e., with 1 week off-treatment [PC-W]).

Materials and methods: Medical records of consecutive patients treated between 2000 and 2018 were reviewed; 707 patients were analyzed for demographic and clinical characteristics, effectiveness and toxicity.

Results: PC-3W was administered to 402 patients (median age, 60.5 years) and PC-W to 305 patients (median age, 62.5 years). Most patients (91.4%) were diagnosed at stage III-IV. Notwithstanding a higher proportion of residual disease and older patients in the PC-W group, median progression-free survival was 21.4 months and 13.2 months for PC-W and PC-3W, respectively; median overall survival was 75.2 and 54.0 months for PC-W and PC-3W, respectively. Cox proportional hazards model indicated improved survival for patients treated with PC-W (hazard ratio, 0.54). Similar results were observed for older patients diagnosed at ≥75 years. PC-W demonstrated a better safety profile, with lower incidence of neuropathy, neutropenia, and alopecia.

Conclusion: PC-W is as active and better tolerated than the standard PC-3W regimen. PC-W may serve as an alternative option for elderly or frail patients.

Implications for practice: Weekly scheduling of paclitaxel 80 mg/m² and carboplatin AUC2, administered on days 1, 8, and 15 in a 28-day cycle (PC-W) for first-line therapy for advanced ovarian cancer, is as active and better tolerated than the standard regimen of carboplatin and paclitaxel (175 mg/m² ) every 3 weeks (PC-3W). It is possible that the weekly holiday on day 21 in the PC-W regimen may ensure better completion rates (which may result in treatment delays for toxicity in PC-3W). The results of this retrospective analysis highlight the weekly regimen as a valid treatment option, especially for elderly patients and those with significant comorbidities.