Intravascular NK/T-cell lymphoma: a report of five cases with cutaneous manifestation from China

Background: Intravascular lymphoma is a rare type of lymphoma that frequently affects the skin and is usually of B-cell origin. This lymphoma type is very rare and not recognized as a separate entity in the 2008 World Health Organization classification of hematopoietic and lymphoid tissue tumors. Methods: We reported five cases of intravascular NK/T cell lymphoma with cutaneous manifestation and reviewed 12 published cases involving Chinese patients with similar characteristics. Results: All five patients were adults who exhibited red or brown patches or plaques on the lower extremities or trunk; four cases were associated with B symptoms; one case developed subsequent to a lymphoma on the face (possibly extranodal NK/T cell lymphoma, nasal type). Histopathologically, all patients exhibited abnormal, medium-sized intravascular lymphocytes in the dermis and subcutaneous tissues. All patients were positive for CD2, CD3 epsilon, CD56 and cytotoxic proteins. All cases were Epstein-Barr virus (EBV) positive. Four of FIVE patients died of lymphoma within a few months of diagnosis. Conclusions: Intravascular NK/T-cell lymphoma is a rare highly aggressive and EBV-associated lymphoma that is prone to develop in Chinese patients. The relationship between intravascular NK/T-cell lymphoma and extranodal NK/T-cell lymphoma, nasal type, requires clarification.