LY20 Cutaneous lymphoma in the post-transplant setting

Abstract

Post-transplant lymphoproliferative disorders (PTLDs) are mostly Epstein–Barr virus-induced B-cell lymphomas. A small minority are of T-cell origin, and of those, primary cutaneous T-cell lymphoma is rare. We present a rare case of mycosis fungoides occurring post-transplant, with subsequent development of systemic peripheral T-cell lymphoproliferative disorder. A 67-year-old man with cadaveric renal transplant, maintained on mycophenolate mofetil and ciclosporin, presented 25 years post-transplant with an eczematous rash that over a year developed into scaly annular and indurated plaques affecting his trunk and limbs. Diagnostic biopsies demonstrated a predominantly CD4+ T helper cell infiltrate, with partial loss of CD5 and CD7, and > 10% CD30 positivity. T-cell gene rearrangement studies demonstrated T-cell receptor clonality. A staging computed tomography (CT) scan identified an indeterminate 11-mm subpleural nodule on the left lower lobe for monitoring. A diagnosis of mycosis fungoides (stage 1B) was made. Mycophenolate mofetil was discontinued and prednisolone started. The patient received skin-directed treatment with low-dose radiotherapy to symptomatic lesions followed by total-skin electron beam (TSEB) phototherapy (12 Gy in eight fractions) due to progressive skin involvement. Following completion of TSEB phototherapy, he reported breathlessness and intermittent fever. Repeat CT thorax 1 month later showed an enlarged nodule on the left lower lobe and new large left-sided pleural effusion. Diagnostic cytology of pleural fluid was suspicious of T-cell lymphoma, and left pleural biopsy confirmed pleomorphic CD30+ EBER− T-cell lymphoproliferative disorder. He is planned to start dose-modified GCVP (rituximab, gemcitabine, cyclophosphamide, vincristine, prednisolone). To date, there have been fewer than 15 case reports of mycoses fungoides occurring after solid organ transplant, often with a less favourable prognosis than in immunocompetent individuals. This case illustrates an exceptionally rare systemic T-cell PTLD possibly arising from mycosis fungoides (clonality pending). It emphasizes need for heightened vigilance for progressive dermatoses in immunosuppressed patients and highlights the risk of aggressive transformation. Early recognition and close multidisciplinary management are critical to balance effective lymphoma treatment with graft preservation.