Epidermal growth cell receptors (EGFR) play a key role in tumor proliferation. Their inhibitors (anti-EGFR) are promising treatments for various types of cancers. Papulopustular follicular eruptions are the most frequent dermatological side effect and occur in 45 to 85% of patients receiving this treatment. Paronychias appear after several weeks of treatment. They are painful and impair hand and foot function. A positive correlation seems to exist between the intensity of the papulo-follicular eruption, tumor regression and survival.