Cetuximab and panitumumab in a patient with colon cancer and concomitant chronic skin disease: a potential beneficial effect on psoriasis vulgaris.

Monoclonal antibodies against epidermal growth factor receptor (EGFR) are used in the treatment of advanced colorectal cancer. However, these agents can induce severe dermatological side effects that discourage their administration in patients with chronic dermatological disease. EGFR plays a key role in normal skin development and immunological function, and is expressed in various tissues and organs, although contrarily, it is overexpressed in psoriasis-related skin lesions. Thus, discussion is ongoing regarding the putative pathological role and therapeutic potential of this protein. We herein report on a patient with advanced colon cancer and concomitant long-standing psoriasis vulgaris who received anti-EGFR antibody monotherapy as a third-line treatment for metastatic disease. One week after the initiation of treatment, the patient's skin lesions dramatically subsided and the improvement was sustained during therapy. Based on this case, we propose that anti-EGFR antibody therapy is not necessarily contraindicated in patients with psoriasis vulgaris. Moreover, the findings reaffirmed that EGFR is an important molecule in the pathology of psoriasis.