Anaplastic large cell malignant lymphoma with extensive eosinophilic or neutrophilic infiltration

We describe the clinicopathological features of eight cases of Ki-1 positive anaplastic large cell malignant lymphoma (Ki-1 ALCL) in which there was extensive infiltration by eosinophils and/or neutrophils in the absence of necrosis.

The patients comprised four males and four females with an age range of 24-74 years. Five cases had originally been diagnosed as Hodgkin's disease and one as true histiocytic lymphoma. In all cases, there was massive infiltration by eosinophils and/or neutrophils sometimes to such an extent that malignant cells were obscured. Immunohistochemical staining was performed using the monoclonal antibodies CD30, CD15, CD45, CD20, CD3, CD45RO, epithelial membrane antigen (EMA), CAM5.2, vimentin and CD68. In all cases, tumour cells were strongly positive for CD30 but negative for CD15. One case was positive for CD45 but none expressed B or T-cell markers. Five cases were positive for vimentin and two for EMA. Three of seven patients in whom adequate clinical details were available had stage III or IV disease at presentation and four exhibited B symptoms. Four patients had a peripheral neutrophilia and one a peripheral eosinophilia.

The study shows that an eosinophil and/or neutrophil-rich variant of Ki-1 ALCD exists, expanding the morphological spectrum of this tumour.