Acral interdigital melanoma mimicking tinea pedis

We report a case of interdigital acral nodular melanoma on the right fourth toe cleft of a 56‐year‐old Caucasian man that was initially misdiagnosed and mistreated as tinea pedis for over one year. Despite undergoing complete tumor resection and therapeutic lymphadenectomy, as well as adjuvant immunotherapy, the patient died of metastatic disease 18 months after his first visit. This case emphasizes that refractory interdigital dermatophytoses should raise suspicion for the possibility of concomitant malignant neoplasms. Histopathological assessment is indispensable for definite diagnosis of acral interdigital lesions not responding to treatment.