[Clinicopathological features of intravascular peripheral T-cell lymphoma]

Objective: To summarize the clinical and pathological features of intravascular NK and T cell lymphoma for better understanding of such disease to reduce misdiagnosis and miss-diagnosis. Methods: Clinical and pathological features were analyzed retrospectively in one case of intravascular peripheral T-cell lymphoma, not otherwise specified (IVPTCL, NOS) , with literatures review. Results: The case presented in this study was a 66-year-old man. PET/CT scan showed multiple lymph nodes enlargement throughout the body. Normal lymph node structure could not be observed by tissue biopsy, while lymph follicles were partially disrupted. High-power light microscope revealed a large number of blood vessels with diffuse proliferation and dilation, where atypical lymphoid cell mass was restricted in the lumen and partially infiltrated the large blood vessel wall. These tumor cells were medium to large with moderate cytoplasm. The nucleus was irregular, single or multiple nucleoli could be seen, chromatin was condensed, some were empty and bright, and mitotic figures could be seen. Immunohistochemical staining showed that the neoplastic cells were positive for expression of CD3, CD43, CD8, GrB, TIA-1 and perforin. EBER in situ hybridization result was negative. Polymerase chain reaction test identified a clonal gene rearrangement of T-cell receptor γ. The patient was treated with CHOP in combination with chidamide, but died of infection and cardiopulmonary failure within 2 months. 56 cases of intravascular NK/T cell lymphoma with definite classification were collected from relevant literatures, including 47 cases with nasal type of extranodal NK/T cell lymphoma (27 were male and 20 were female) , 8 cases with anaplastic large cell lymphoma (3 males and 5 females) , and only one case with de nova IVPTCL, NOS in brain. We report the second case of IVPTCL,NOS, and notably originated from lymph node for the first time. Conclusions: Intravascular NK/T cell lymphoma is a highly aggressive disease with no effective treatment at present. Involvement of Lymph node has rarely been reported, and further studies on more cases are necessary.