Which patients, if any, should receive prophylactic antibiotics when starting therapy with epidermal growth factor receptor (EGFR) inhibitors? 


—Jeanette Pasche, RN-BC, CEN


The EGFR inhibitors used in the United States are cetuximab (Erbitux) and erlotinib (Tarceva). The agents are used to treat multiple cancers including lung, head and neck, and pancreatic adenocarcinoma. Cetuximab is a monoclonal antibody administered intravenously; erlotinib is a tyrosine kinase inhibitor that is taken orally. Both are associated with the occurrence of an acneiform rash. The rash is maculopapular in nature, and occurs most frequently on the face, neck, chest, scalp, and upper back. Patients may also complain of itching in the sites where the rash occurs. In clinical studies, rash occurred in more than 75% of patients taking cetuximab and in 49% to 75% of patients taking erlotinib, with up to 18% of patients experiencing grade 3 rash in some studies.1,2

Although the rash appears similar to acne, its management is different. Moisturizing, avoiding irritants, and decreasing inflammation are crucial components. Patients should use mild cleansers (eg, Cetaphil) and apply thick emollient moisturizers (eg, Aquaphor or Eucerin) twice daily to affected areas. Topical antibiotics (eg, clindamycin) to minimize inflammation are an important early intervention, and may be utilized with topical corticosteroids. Systemic antibiotics such as doxycycline and minocycline may also be used to reduce inflammation and rash severity. Patients with grade 3/4 rash should hold their EGFR inhibitor until the rash has improved to grade 1 or less. Dose-reductions or permanent discontinuation should be considered for severe rashes or if a grade 3/4 rash recurs.

Preventative strategies seek to minimize the occurrence and severity of the rash. The Multinational Association for Supportive Care in Cancer (MASCC) guidelines for the prevention and treatment of EGFR inhibitor-associated dermatologic toxicities recommend prophylactic management for all patients receiving EGFR inhibitors if possible per patient- and prescriber-specific factors.3 All patients beginning treatment with an EGFR inhibitor should minimize sun exposure by wearing wide-brimmed hats and should wear broad spectrum sunscreen containing zinc oxide. Early initiation of moisturizing creams and mild cleansers is also an important preventive strategy. The MASCC guidelines also recommend initiating prophylactic doxycycline and topical hydrocortisone in patients receiving EGFR inhibitors, although this may not be done in all patient populations in the United States.

Patients who are receiving concurrent radiation should undergo aggressive skin care. Patients receiving radiation should consult with their radiation team regarding the optimal timing of topical product application, as some (such as sunscreen) may affect administration of radiation. ONA 

Disclaimer: The author reported no relationships, financial or otherwise, to products or devices related to the content of this article.



Lisa Thompson is assistant professor, Department of Clinical Pharmacy, University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, Colorado.


REFERENCES


1. Erbitux [package insert]. Princeton, NJ: Bristol-Myers Squibb Company; 2013.

2. Tarceva [package insert]. San Francisco, CA: Genentech USA, Inc; 2012.

3. Lacouture ME, Anadkat MJ, Bensadoun RJ, et al; MASCC Skin Toxicity Group. Clinical practice guidelines for the prevention and treatment of EGFR inhibitor-associated dermatologic toxicities. Support Care Cancer. 2011;19(8):1079-1095.