LY21 A rare case of cutaneous CD4-positive cytotoxic T-cell lymphoma

Abstract

Cutaneous CD4-positive cytotoxic T-cell lymphoma is a rare subtype of cutaneous T-cell lymphoma with heterogeneous clinical presentations. We report a case with an aggressive course culminating in life-threatening skin failure and an excellent therapeutic response. A 65-year-old woman presented with a 2-year history of a pruritic erythematous rash, initially localized to the torso and back, which gradually became generalized before rapidly deteriorating over 4 months. She developed confluent erythematous macules with erosions, skin tightness, scaling, alopecia and exudative fluid loss from the lower limbs. Thermoregulation was impaired, with dry, fragile and tender skin. This was associated with B symptoms, palpable lymphadenopathy, anaemia (haemoglobin 84 g L−1), hypoalbuminaemia (16 g L−1) and a rapid decline in performance status from 0 to 3, necessitating urgent hospital admission with skin failure and sepsis. Multiple skin biopsies showed ulceration, interface inflammation and possible folliculotropism without definitive evidence of lymphoma. A mildly positron emission tomography-avid lymph node was initially interpreted as dermatopathic. Subsequent comparison of multiple skin sites and the lymph node demonstrated a clonal CD4-positive, CD8-negative, CD30-negative T-cell infiltrate with partial loss of CD5 and frequent TIA-1 expression. Identical T-cell receptor gene rearrangements in skin and lymph node specimens supported the diagnosis of CD4-positive cytotoxic T-cell lymphoma. Following clinical optimization, dose-attenuated chemotherapy with cyclophosphamide, vincristine and prednisone (CVP), followed by obinutuzumab-CVP, achieved a partial response but was complicated by severe treatment-related toxicity and neutropenic sepsis. Treatment was transitioned to total-skin electron beam radiotherapy (10 Gy in five fractions), resulting in near-complete cutaneous response, with residual disease confined to sanctuary sites. Systemic symptoms resolved, laboratory parameters normalized, and performance status improved. By 5 months’ ­follow-up, she remains well with plans for radiotherapy to sanctuary sites and maintenance low-dose methotrexate. This case highlights prolonged inflammatory mimicry, diagnostic challenges and management complexity in rare cutaneous T-cell lymphomas.