RESUMEN
Psoriasis is a systemic inflammatory cutaneous disease that affects approximately 2% of the world's population. Systemic treatments and biologic treatment therapies are a powerful option for patients with moderate to severe psoriasis. Some studies from the literature indicate an overall small, but increased, risk of neoplasia in patients with psoriasis treated with phototherapy or systemic medication. The relationship between psoriasis and malignancy is not very well established; there are few studies with conflicting results. We present the case of a 31-year-old male patient, diagnosed with psoriasis, who was deemed eligible for systemic therapy. Treatment with methotrexate was initiated, but without a satisfactory outcome. Given the patient's resistant disease involving 15% of his body surface, his desire to have a clear skin, besides his being naïve to biologic therapy, he was proposed to start treatment with secukinumab 300 mg monthly. The patient experienced complete clearance of lesions and was followed-up on the basis of clinical and biological parameters. There are limited data concerning the relationship between melanocytic lesions, psoriasis and melanoma. Immunologic pathways implicated in psoriasis induce a reduction in the number of melanocytic nevi. Nevertheless, little is known concerning the association of melanocytic nevi with psoriasis. Thorough skin examination, meaning clinical and dermoscopic evaluation of melanocytic lesions, must be encouraged in patients treated with systemic therapies such as biologic agents.