Second-line panitumumab as a triweekly dose for patients with wild-type KRAS exon 2 metastatic colorectal cancer: a single-institution experience

Abstract

Objective: Panitumumab administered as monotherapy in colorectal cancer (CRC) has shown response and disease stabilizationrates of approximately 30%. The current study aimed to evaluate the progression-free survival (PFS) and overall survival (OS) ofpatients with metastatic colorectal cancer (mCRC) treated with panitumumab every 3 weeks as a second line treatment.

Methods: This study is a retrospective analysis of 18 patients, aged more than 18 years, with wild-type KRAS exon 2 mCRC treatedwith panitumumab as a second-line single agent after progression on first-line chemotherapy.

Results: The median number of courses received was 10 (range, 4-29), and the median duration of treatment was 30 weeks (range,12-96 weeks). After a median follow-up period of 13 months, the median PFS was 6 months (range, 4.3-7.7 months) and themedian OS was 11 months (range, 7.4-14.5 months). The median PFS was 4 months for patients with < grade 2 skin toxicity and 6months (range, 4.5-7.5 months) for patients with ≥ grade 2 skin rash (P=0.05). The median OS was 9 months (range, 6.4-11.5months) and 14 months (range, 11.6-16.3 months) for the two groups of patients (P=0.002).

Conclusions: Panitumumab given every 3 weeks is effective and well tolerated in patients with advanced CRC that progressed afterstandard chemotherapy.