Clinicopathologic analysis of five cases of cutaneous intravascular natural killer/T-cell lymphoma

Objective To improve the understanding of cutaneous intravascular natural killer/T-cell lymphoma (CIVNKTC). Methods Clinical data on five cases of CIVNKTC were collected. The histopathological feature, treatment and prognosis of CIVNKTC were retrospectively analyzed and discussed. Results Of the 5 patients, 1 was male and 4 were female. The age of onset ranged from 38 to 83 years (average, 56.2 years). All the patients presented with multiple plaques and nodules as the primary symptoms. Histopathological examination revealed vasodilatation in the dermis and subcutaneous tissue, as well as atypical lymphoid cells with large hyperchromatic nuclei containing 1 -2 small nucleoli in dilated veins. Immunohistochemical studies of tumor cells showed positive staining for CD3e, cytotoxic proteins (including T cell-restricted intracellular antigen-1, granzyme B and perforin) and Epstein-Barr virus (EBV)-encoded microRNA, but negative staining for cytokeratin, CD20, CD79a, CD4 and CD8. Furthermore, the tumor cells stained positive for CD56 in two patients. Among the 5 patients, only 2 received chemotherapy and the remaining received no treatment. During a 24-month follow-up, 4 patients died, and only 1 survived with the tumor. Conclusion CIVNKTC is a rare extranodal Hodgkin's lymphoma with distinct histologic manifestations and immunophenotypes, rapid and aggressive clinical course, and poor prognosis. Key words: Lymphoma, extranodal NK-T-cell; Skin manifestations; Pathological processes; Immunohistochemistry; Intravascular lymphoma