A Case of Adult T-cell Leukemia Masquerading as Mycosis Fungoides

摘要

Introduction and Initial Presentation This 81 year old Japanese American male presented 9 years ago with a rash that was diagnosed as psoriasis and was treated with 14 weeks of light therapy. Shortly after this therapy a skin biopsy of the right buttock revealed an atypical T-cell infiltrate consistent with mycosis fungoides with the malignant cells positive for CD 2,3,4, and 5 but negative for CD7 and 8. The epidermis showed hyperkeratosis, hyperparakeratosis, and acanthosis and there was a band-like lymphocytic infiltrate in the superficial dermis. Epidermotropism and Pautrier microabscesses with atypical lymphocytes with convoluted nuclei and occasional large cells were noted. T-cell gene rearrangement and HTLV-1 serology were positive. Bone marrow examination was unrevealing. While the patient had not ever been in Japan, his father came from Kyushu.The patient received therapy with PUVA with an initial response, then experienced progression in skin. Treatment with topical BCNU and extracorporeal photopheresis were also rendered; again with initial short-lived responses, then progression of the skin rash. Two years after the initial diagnostic skin biopsy, the patient had a PET scan showing right hilar, axillary, and inguinal adenopathy.The patient began therapy with bexarotene with a complete response in skin and continued on bexarotene in good health for 3 years. He then presented with a hemoglobin of 8.9 and white blood cells of 12,800. CT scanning showed bilateral perihilar alveolar infiltrates, a 1.5 cm density at the right apex of the lung, mediastinal and right hilar adenopathy and splenomegaly with peripheral hypodensities. Diagnostic Work-Up At this time, he was referred to a tertiary center. On physical examination the patient was a frail, ill-appearing elderly man who had no skin lesions, and no palpable adenopathy. The liver was 10 cm below the right costal margin and the spleen was 8 cm below the left costal margin in the mid-clavicular line. Flow cytometry of his blood showed that 8% of lymphocytes were abnormal T-cells with positive CD 2,3,4,5,25 and 52 and a T-cell gene rearrangement was present. Human T-cell leukemia type 1 serology was positive by ELISA screen with Western blot confirmation.