Meta-analysis of incidence and risk of hypomagnesemia with cetuximab for advanced cancer.

BACKGROUND Cetuximab is often used in patients with colorectal cancer, head and neck cancer, and other cancers. Hypomagnesemia is a major adverse event that was often ignored in studies. The aim of this meta-analysis is to gain a better understanding of the overall incidence and risk of hypomagnesemia in patients who received cetuximab-based therapy. METHODS Databases, including Pubmed, EMBASE, The Cochrane Library, American Society of Clinical Oncology (2000-2008), and Web of Science, were searched to identify relevant studies. Eligible studies were prospective phase II/III clinical trials of patients with cancer assigned cetuximab at a dose of 400 mg/m(2) i.v. on day 1 and 250 mg/m(2) weekly thereafter. The primary endpoint was incidence of hypomagnesemia. RESULTS Nineteen clinical reports were identified which included a total of 4,559 patients available for analysis, with 3,081 patients assigned cetuximab-based treatment. This result showed a high incidence of grade 3 and 4 hypomagnesemia (5.6%; 95% CI = 3.0-10.2) and a high incidence of all-grade hypomagnesemia associated with cetuximab-based therapy for advanced cancer (36.7%; 95% CI = 22-54.4). Compared with non-cetuximab therapy, cetuximab-based therapy has a higher risk of grade 3 and 4 hypomagnesemia (4.75; 95% CI = 3.661-6.18) and all-grade hypomagnesemia (4.75; 95% CI = 3.661-6.18). CONCLUSION Cetuximab-based therapy is associated with a significant risk of hypomagnesemia. Early monitoring and effective management of hypomagnesemia are important for patients that received cetuximab-based therapy.