Tre-P-05 - Use of mogamulizumab for refractory Sézary syndrome in real clinical practice: report of three cases

Abstract

Sézary syndrome (SS) is a cutaneous T cell lymphoma (CTLC) with poor prognosis which can present de novo or secondary to mycosis fungoides (MF). We report our experience treating patients with SS with mogamulizumab (n=3). <h3>Case 1:</h3> A 76-year-old woman presented with an 8-year history of refractory erythroderma. Skin biopsy showed dermal lymphocytic infiltrate with aberrant phenotype. Blood flow cytometric analysis detected 77% pathologic T-lymphocytes (TL) with SS phenotype and positive T-cell receptor (TCR) ϒ gene rearrangement. Lymph node biopsy showed SS infiltration. She was diagnosed with stage IVA1 SS (T4N1M0B2). Due to disease progression after treatment with bexarotene, mogamulizumab was started following the usual protocol. Patient achieved complete clinical response (CR) since the 2nd infusion in skin, blood and lymph nodes. She presented grade IV neutropenia after the 6th infusion which resolved with filgastrim, and a grade II lymphopenia after the 5th infusion which resolved with posology spaced to every 6 weeks. Patient continues disease-free after 12 months of treatment. <h3>Case 2:</h3> A 66-year-old woman presented with a 1-year history of erythroderma. Skin biopsies were consistent with MF. Blood flow cytometric analysis detected 59.2% of pathological TL with SS phenotype and positive TCR ϒ gene rearrangement. Lymph node biopsy showed SS infiltration. Diagnosis of stage IVA2 SS (T4N3M0B2) was stablished. She was treated with extracorporeal photopheresis, interferon α-2B, bexarotene and gemcitabine with partial response. Treatment with mogamulizumab was started with complete CR after the 4th infusion in skin, lymph nodes, and blood with good tolerability. She received an allogeneic bone marrow transplant after the 5th cycle and continues disease-free after 100 days post-transplant. CASE 3 A 36-year-old man presented with follicular infiltrated papules and alopecia affecting most of the body surface. Blood flow cytometric analysis showed 93% of pathological TL and positive TCR ϒ gene rearrangement. Skin biopsy was consistent with MF. Lymph nodes showed SS infiltration. Patient was diagnosed with Stage IVA2 SS (T2N3M0B2). He was treated with bexarotene and brentuximab with initial CR but disease progression after 10 cycles. Treatment with mogamulizumab was started with initial improvement but failure after 6 months. Mogamulizumab is a monoclonal antibody that selectively binds to CCR4 present on atypical TL. To date, only a series of 13 patients with CTCL treated with mogamulizumab in clinical practice has been reported, with good tolerability and CR in blood and skin. In our series 2 out of 3 patients presented an impressive CR in all aspects of the disease. One patient developed neutropenia and lymphopenia in relation to mogamulizumab, which resolved after specific treatment. This series supports the use of mogamulizumab in patients with refractory SS. Larger series are needed to evaluate the use mogamulizumab for CTCL in routine clinical practice.