A 53-year-old Caucasian woman presented with a 40-year history of severe plaque psoriasis. The patient had recalcitrant psoriasis that was unresponsive to multiple conventional therapies such as methotrexate and acitretin. The patient also had a 20-year history (>800 treatments) of psoralen plus ultraviolet A (PUVA) therapy. Her past medical history was notable for a benign compound nevus on the left anterior thigh, which was completely excised in January 2011. In January 2012, the patient was screened (including physical examination, baseline laboratory studies, and screening for latent tuberculosis and chronic viral infections) and began etanercept therapy (50 mg subcutaneously twice weekly). After 3 months, the patient was responding insufficiently to etanercept and was switched to infliximab (5 mg/kg at weeks 0, 2 and 6, and then every 8 weeks thereafter). This treatment resulted in the complete disappearance of her psoriasis. Twelve months after beginning the infliximab treatment, the patient developed palpable lymphadenopathy in the left inguinal region. Given the suspect nature of the palpable mass, the patient underwent an inguinal lymph node biopsy. The histology of the biopsy specimen showed a metastatic melanoma. Positron emission and computed tomography scans were negative for distant metastatic disease. Infliximab was discontinued and a complete inguinal lymph node dissection was performed, which revealed no additional nodal involvement. A full skin evaluation did not reveal any suspicious lesions, but 4 cm below the metastatic lymph node, the scar from the previously removed nevus could be seen (fig. 1). The histopathologic slides of the excised nevus were reviewed along with immunohistochemical studies, which led to the definite diagnosis of nevoid melanoma (Breslow thickness 1.44 mm; fig. 2). A BRAF V600E mutation was detected and the patient was enrolled in a clinical trial of combined adjuvant therapy with dabrafenib and trametinib.