591P - Colon Cancer Adjuvant Mfolfox-6 – Survival Impact of Oxaliplatin Reduced Dose-Intensity

Abstract

ABSTRACT Background Adjuvant colon cancer treatment may include the oxaliplatin/fluoropirimidine combination. This association has shown benefit on progression free survival (PFS) and overall survival (OS) compared to fluoropirimidine monotherapy in these patients. Adverse events are frequent and may cause delay on treatment delivery or drug dose reduction. The survival impact of oxaliplatin reduced dose intensity (RDI) is unknown. Objective Evaluation of survival impact of oxaliplatin RDI in colon cancer patients treated with adjuvant mFOLFOX-6. Material and methods: A consecutive series of colon cancer patients treated with adjuvant mFOLFOX-6 at our institution between 09/2004 and 11/2009. The impact of Oxaliplatin Results There were no differences in age, sex, ECOG, comorbidity, histologic grade and stage distribution between groups. Two hundred and seventy seven (277) patients were identified (53% in group A). Fifty nine percent (59%) of patients completed the 12 mFOLFOX-6 cycles and the median duration of adjuvant chemotherapy was 6,5 months. The mean oxaliplatin dose-intensity was 71% (median 74%). Adverse events led to dose reduction and drug suspension in 53% and 40% of patients, respectively. There were 3 deaths during treatment. The main causes to RDI were grade ≥ 3 hematologic toxicity (47%) and neuropathy (12%) – median cumulative oxaliplatin dose at first neurologic severe event was 1024 mg. There were no differences in PFS and OS between RDI groups, neither after stage stratification. Conclusion In our cohort patient's characteristics and toxicity profile were similar to published trials. FOLFOX conclusion rate was inferior than the described in MOSAIC trial (59% vs 74,7%). Despite the inferior accomplishment rate, there was no impact in PFS and OS in oxaliplatin RDI Disclosure All authors have declared no conflicts of interest.