Chemotherapy compliance, tolerance and efficacy in elderly and non-elderly patients with metastatic colorectal cancer: a single institution comparative study.

PURPOSE To evaluate whether elderly patients with metastatic colorectal cancer (mCRC) receive chemotherapy of suboptimal intensity and duration, mainly due to fears of poor compliance and/or excessive toxicity. METHODS We carried out a retrospective analysis in a series of 94 mCRC patients. Using the cut-off of 70 years, we compared elderly patients with their younger counterparts in terms of treatment delivery [type, dose intensity (DI), relative dose intensity (RDI), duration], chemotherapy toxicity and efficacy [objective response rate (ORR), overall survival (OS) and progression-free survival (PFS)]. RESULTS Complete data were available for 72 patients (76.6%) among which 38 (52.8%) were elderly. As compared to the younger, elderly patients were more likely to receive single-agent chemotherapy (13.1 vs 0%, p<0.001). The mean number of chemotherapy cycles was 6.2 for the elderly and 8.3 for the non-elderly patients who received either the FOLFOX or FOLFIRI regimen (p=0.142) and 5.1 vs 5.0 for those who received either the XELOX or XELIRI regimen, respectively (p=0.831). In oxaliplatin-containing regimens, elderly patients received 42.8% of the planned dose, as compared to 78.4% for the younger ones (p=0.012). DI for oxaliplatin was higher in non-elderly than in the elderly (46.66 mg/ m(2)/week vs 32.47 mg/m(2)/week, p=0.008). No difference was observed in the rate of severe (grade III-IV) toxicities. ORR, PFS and OS were similar between the two groups. CONCLUSION Despite the inferior type and intensity of chemotherapy, elderly patients derived equivalent benefit to their younger counterparts. These data further support the use of optimal chemotherapy in elderly patients with mCRC.