Reactions 1412 - 28 Jul 2012

SCetuximab

Hypomagnesaemia: 5 case reportsTwo women and three men aged 56–78 years developed

grade 3–4 hypomagnesaemia after starting cetuximab formetastatic colorectal cancer [route not stated; dosages notclearly stated]. They were identified as part of aretrospective analysis of routine monitoring of serummagnesium levels in patients receiving cytotoxicchemotherapy.

All five patients developed grade 3 hypomagnesaemia35–280 days after starting cetuximab; two progressed tograde 4 hypomagnesaemia after 175 and 273 days,respectively. The patients’ lowest serum magnesium levelswere 0.24–0.37 mmol/L. Duration of cetuximab therapy*

ranged from 10 to 45 weeks. No major clinical symptomsattributable to low serum magnesium levels were noted inthe five patients; however, grade 1 fatigue was reported inone woman. All five patients also had serum calcium levelsbelow the lower limit of normal; the lowest serum calciumlevels ranged from 1.32 to 1.85 mmol/L. Serum potassiumlevels were 2.7–4.8 mmol/L. Survival from the start oftreatment ranged from 3 to 33 months for the five patients.

Author comment: "[A]symptomatic hypomagnesaemia iscommon in metastatic colorectal carcinoma patientstreated with cetuximab. . . Serum magnesium should beroutinely assessed in cancer patients treated with new agents,specifically with agents targeting [epidermal growth factorreceptor]."

* Most patients in the retrospective analysis received cetuximab(loading dose of 400 mg/m2 then 250 mg/m2 weekly), irinotecan,folinic acid [leucovorin] and fluorouracil; however, one patientreceived a modified version of this regimen, one received theregimen with irinotecan omitted and one patient receivedcetuximab monotherapy.

Melichar B, et al. Hypomagnesaemia in patients with metastatic colorectalcarcinoma treated with cetuximab. Hepato-Gastroenterology 59: 366-371, No. 114,Apr 2012. Available from: URL: http://dx.doi.org/10.5754/hge10330 - CzechRepublic 803074295

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Reactions 28 Jul 2012 No. 14120114-9954/10/1412-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved