Background: In an ageing population, a greater proportion of geriatric patients will be considered for systemic chemotherapy. Colorectal cancer (CRC) is a common malignancy and will be a major health issue in geriatrics. We used the MAX population to investigate whether age affected the improved outcome found in CRC when bevacizumab is added to capecitabine chemotherapy.
Patients and methods: MAX, a three arm study of Capecitabine (C) versus CBevacizumab (CB) versus CBMitomycin C (CBM), found an improvement in progression-free survival (PFS), with addition of B [+/- mitomycin C (MMC)] to C. This analysis assesses the effect of adding B (+/- MMC) to C on PFS, overall survival (OS), response rate (RR), toxicity and dose intensity in geriatric patients (age ≥ 75 years).
Results: Ninety-nine patients (21%) were aged 75-86 years. Baseline characteristics were well balanced. Eighty-eight per cent commenced C at the lower optional dose of 2000 mg/m(2)/day; days 1-14, q21 (61% for <75 years) and 88% were Eastern Cooperative Oncology Group 0-1. Co-morbidities were as expected in this population. The addition of B significantly improved PFS in geriatric patients(C 5.8 months versus CB 8.8 months, Hazard ratio (HR) 0.65 and C versus CBM 10.4 months HR 0.38). The interaction test for OS, RR and PFS revealed no impact of age. Dose intensity was maintained >90% in all patients. There were no major differences in toxicity patterns between age cohorts.
Conclusions: Addition of B to C significantly improved PFS in this geriatric population, with similar benefits to those aged <75 years. Treatment was well tolerated with no signal of increased toxicity (including thromboembolism) when compared with those aged <75 years.