Effects of Type of Antibody to EGFR and Hypomagnesemia on Overall Survival in First-line Treatment of Patients With Unresectable Advanced/Recurrent Colorectal Cancer

Abstract

Aim: To clarify the differences in overall survival (OS) depending on the presence or absence of hypomagnesemia and the type of epidermal growth factor receptor antibody as first-line therapy for metastatic colorectal cancer (mCRC). Patients and Methods: We retrospectively compared the OS in 68 patients who received cetuximab or panitumumab for mCRC at Ogaki Municipal Hospital (Ogaki, Japan) between January 2010 and December 2019. Results: The complete and partial response rates in the cetuximab and panitumumab groups were 60.0% and 72.0%, respectively (p=0.470). The OS was significantly longer in the panitumumab group (median=1,007 days, range=208-1,433 days) than in the cetuximab group (median=735 days, range=181-2,391 days; p=0.047). Hypomagnesemia did not contribute to differences in OS in the two groups. Conclusion: Panitumumab may lead to a longer OS than cetuximab as first-line treatment of mCRC. The presence or absence of hypomagnesemia in cetuximab- or panitumumab-treated patients did not affect OS.