Effective therapy of epidermal growth factor receptor inhibitor-associated dermatologic side effects in a patient with metastatic colorectal cancer: a case report and review of literature

Overexpression and impaired signaling of the epidermal growth factor receptor (EGFR) are involved in the cancerogenesis. The EGFR inhibitors such as cetuximab have shown efficacy in the targeted therapy of neoplasm. The acneiform rash has been revealed as the most common side effect of treatment, usually occurring within 2 weeks after therapy onset. We report perifollicular pustules and papules with impetiginization in a 63-year-old patient with metastatic colorectal cancer treated with cetuximab. The neoplasm was diagnosed in 2008 and treated surgically (resection of the sigmoid). After 3 years, a combined therapy was administered due to the disease progression. It consisted of cetuximab and FOLFOX (Folinic acid, Fluorouracil, Oxaliplatin) chemotherapy regimen. The effective dermatologic management (with systemic doxycycline and topical tacrolimus and fusidic acid) of the skin toxicity allowed for maintenance of oncologic treatment. Despite the proper dermatological therapy, the described side effects may persist, and the exacerbation of skin lesions can cause discontinuation of treatment of cancer with those modern biological agents (EGFR inhibitors and other kinase inhibitors). When discontinuation is not necessary – cutaneous symptoms adversely affect the quality of life. However, there are reports that recognition of the skin lesions in the course of the above therapies is a good prognostic factor, confirming effectiveness of treatment. Moreover, the association between genetic polymorphisms, the risk of treatment adverse effects and the response of the tumor to monoclonal antibody targeted therapy is well established. This leads to the increasing role of pharmacogenetics in the management of neoplasms.