Hypocellular/lymphohistiocytic variant of Anaplastic Large Cell Lymphoma of lymph node, mimicking granulation tissue

Anaplastic Large Cell Lymphoma (ALCL) is a subgroup of T/null cell non-Hodgkin lymphoma (NHL) in WHO classification. Lymphohistiocytic (LH) variant constitutes about 10% of all ALCLs and characterized by presence of abundant reactive histiocytes that can mask the neoplastic nature of the lesion, leading to misdiagnose as "reactive lymphadenopathy". Here we introduce a 16-year-old female patient, diagnosed as hypocellular LH variant ALCL with unusual histologic feature including granulation tissue- like appearance. We emphasize that in young patients with unusual- looking reactive lymphadenopathy, ALCL should be considered as one of differential diagnoses. A brief review of the nature of the lesion and differential diagnoses is also included.