Objectives To evaluate the risk of incomplete cycles of weekly gemcitabine on survival for patients with platinum-resistant ovarian cancer (PROC).

Methods We collected patients with PROC who received weekly gemcitabine (1000mg/m2; D1, D8 every 3 weeks or D1, D8, D15 every 4 weeks) between 2006–2018. We investigated rates of completed cycles, skipped cycles, dose reduction (DR) and prophylactic granulocyte colony-stimulating factor (G-CSF) usage, tumor response and factors affecting progression-free survival (PFS) and overall survival (OS).

Results A total of 101 patients with PROC received weekly gemcitabine. 58(57.4%) completed scheduled cycles without skip and 86 (85.1%) completed more than 80% of scheduled cycles. DR and the use of G-CSF were observed in 34(33.7%) and 25 patients (24.8%), respectively. Weekly gemcitabine was skipped because of grade3 or more hematologic toxicity(31.7%). Complete response, partial response, stable disease and progressive disease were identified in 1(1%), 12 (11.9%), 26 (25.7%) and 61 (60.4%). In terms of survival, the completion rate of scheduled cycles≥80% was a factor for better OS (median OS, the completion rate of scheduled cycles≥80% vs. <80%, 39.23 months vs. 8.97months, p=0.011), but not for better PFS (median PFS, the completion rate of scheduled cycles≥80% vs. <80%, 2.89months vs. 2.43months, p=0.238). Use of G-CSF was factor for better PFS and OS (median PFS, G-CSF group vs. non-G-CSF group, 2.53month vs. 2.07month, p=0.023; median OS, 39.23months vs. 14.72months, p=0.011)

Conclusions Incompletion of scheduled cycles of weekly gemcitabine may be associated with prognosis, and especially, the completion rate of scheduled cycles<80% may not improve survival in patients with PROC.