From Indolent to Invasive: Tumour-Stage Transformation in Mycosis Fungoides

A 47-year-old man presented to dermatology with a 4-year history of a progressively worsening, pruritic, and painful rash.The eruption began as scaly patches and plaques on the torso and became increasingly raised and widespread over the preceding 4 months.He had a known history of human immunodeficiency virus (HIV), with sustained viral suppression on antiretroviral therapy for 13 years.On examination, he was erythrodermic with widespread nodules involving the face (Panel A), trunk, and limbs (Panel B).The nodules distorted his facial features, producing a leonine facies.Erosions with extensive honey-coloured crusting were noted on the face and neck.Additional findings included palmoplantar keratoderma and palpable cervical, axillary, and inguinal lymphadenopathy.Peripheral blood flow cytometry revealed a limited population of atypical T-lymphocytes.Staging computed tomography demonstrated generalised lymphadenopathy involving the bilateral cervical, axillary, para-aortic, iliac, and inguinal nodes.A skin punch biopsy confirmed the diagnosis of mycosis fungoides with large-cell transformation.The patient was initiated on combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone, with marked clinical improvement noted after two cycles (Panel C).