A 55-year-old man receiving cetuximab for metastatic colorectal cancer develops an acneiform papulopustular eruption on the face and upper trunk starting in week 2 of therapy. Prophylactic use of which agent has been shown to reduce the severity of this eruption?

• A Oral isotretinoin 20 mg daily
• B Topical tacrolimus twice daily
• C Oral acyclovir 400 mg twice daily
• D Oral doxycycline 100 mg daily with topical corticosteroid ✓

Explanation

EGFR inhibitor acneiform eruptions result from EGFR blockade in keratinocytes leading to follicular inflammation, and doxycycline, through its anti-inflammatory action, is the standard prophylactic and therapeutic agent, often paired with a topical corticosteroid and emollient. Isotretinoin is occasionally used in refractory cases but is not the established prophylactic choice. Acyclovir targets herpetic eruptions and tacrolimus addresses inflammatory dermatoses such as atopic dermatitis, neither of which applies here.

Reference: Bolognia Dermatology, 5th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.