Allogeneic stem cell transplantation for patients with advanced primary cutaneous T-cell lymphoma

Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) provides a potentially curative option for patients affected by primary Cutaneous T-Cell Lymphoma (CTCL) in advanced stage. We are reporting 13 patients (8 F; 5 M) with a median age of 52 years (range 41-64 yrs) affected by advanced CTCL. Diagnosis were: panniculitis-like T-cell lymphoma (n=1) large T-cell lymphoma (n=3), NK T-cell lymphoma (n=1), Mycosis Fungoides (MF, n=2), Sezary Syndrome (SS, n=6). Seven patients had a relapsed/refractory disease, 4 patients were in partial remission and 2 in complete remission. All patients but 1 were heavily pretreated and 3 had undergone a previous auto- logous transplant. Six patients were transplanted from a HLA identical sibling, 1 from a HLA mismatched sibling, 4 patients were transplanted from a matched unrelated donor and 2 from umbilical cord blood (UCB) unit. Nine patients received a RIC regimen consisted of thiotepa, fludarabine and cyclophos- phamide (n=7) and thiotepa, fludarabine and busulfan (n=2). Four patients received a myeloablative conditioning (MAC) consisted of cyclophosphamide and busulfan in 2 patients and thiotepa and fludarabine and busulfan in 2. Cyclosporine and methotrexate were used as GVHD prophylaxis in HLA identical transplant. UCB transplant received cyclosporine and myco- phenolate mofetil and cyclosporine and prednisone, respec- tively. Thymoglobulin was added in mismatched transplant. Neutrophil and platelet engraftment were achieved in all but one patients. A grade I-II acute GVHD developed in 4 patients, grade III-IV in one. Chronic GVHD (cGVHD) was observed in 11 patients: 9 limited and two extended. Eleven patients were evaluable for response (2 too early) and achieved a complete remission. Five patients experienced relapse at 3, 8, 9, 10, 17 months from HSCT. Three of them infused donor lymphocyte: a second durable remission was obtained in 2 SS patients, no response was observed in patient with NK T lymphoma. Trans- plant-related mortality occurred in four patients (3 MAC regi- men, 1 RIC regimen). They died as result of multiorgan failure (n=3) and infection plus extensive cGVHD (n=1), 2 at 3 months, 1 at 7 months, 1 at 11. To date at median follow up of 45 months (range 20-85) 9 patients are alive, 6 without evidence of lym- phoma. Our results show a lower transplant-related toxicity by using RIC regimen, suggest a potential curative effect of allogeneic RIC transplant and indicate the existence of a graft versus tumor effect in CTCL.