Cetuximab plus irinotecan after irinotecan failure in elderly metastatic colorectal cancer patients: Clinical outcome according to KRAS and BRAF mutational status

BackgroundScarce data are available about safety and efficacy of cetuximab in elderly metastatic colorectal cancer (mCRC) patients.Patients and methodsWe retrospectively analysed 54 irinotecan-refractory mCRC patients aged ≥ 70 years treated with cetuximab plus irinotecan and evaluated clinical outcome according to KRAS and BRAF mutational status.ResultsMedian age was 73 years (70–82). Main grade 3–4 toxicities were skin rash (15%), diarrhea (19%) and neutropenia (13%). Irinotecan dose reduction was necessary in 39% of patients. Fifty-two (96%) patients were analysed for KRAS and BRAF status. The 29 KRAS wild-type patients achieved better RR (31% vs 4%; p = 0.030) and median PFS (4.21 months vs 3.95 months; p = 0.034; HR: 0.50, 95% CI: 0.27–0.95) when compared with KRAS mutated ones. RR (41% vs 3%; p = 0.001) and mPFS (4.57 months vs 3.78 months, p = 0.001; HR: 0.35, 95% CI: 0.19–0.66) were significantly higher among the 22 KRAS and BRAF wild-type patients compared to the 30 KRAS or BRAF mutated ones.ConclusionCetuximab plus irinotecan has a favourable safety profile in elderly mCRC patients, but a reduced dose of irinotecan should be considered. Such a combination can be a useful option for elderly KRAS and BRAF wild-type patients.