ANAPLASTIC LARGE-CELL MALIGNANT-LYMPHOMA WITH EXTENSIVE EOSINOPHILIC OR NEUTROPHILIC INFILTRATION

Aims: We describe the clinicopathological features of eight cases of K i-1 positive anaplastic large cell malignant lymphoma (Ki-1 ALCL) in w hich there was extensive infiltration by eosinophils and/or neutrophil s in the absence of necrosis. Methods and results: The patients compri sed four males and four females with an age range of 24-74 gears. Five cases had originally been diagnosed as Hodgkin's disease and one as t rue histiocytic lymphoma. In all cases, there was massive infiltration by eosinophils and/or neutrophils sometimes to such an extent that ma lignant cells were obscured. Immunohistochemical was performed using t he monoclonal anti-CD30, CD15, CD45, CD20, CD3, CD45RO, epithelial mem brane antigen (EMA), CAM5.2, vimentin and CD68. In all cases, tumour c ells were strongly positive for CD30 but negative for CD15, One case w as positive for CD45 but none expressed B or T-cell markers. Five case s were positive for vimentin and two for EMA, Three of seven patients in whom adequate clinical details were available had stage III or IV d isease at presentation and four exhibited B symptoms. Four patients ha d a peripheral neutrophilia and one a peripheral eosinophilia. Conclus ions: The study shows that an eosinophil and/or neutrophil-rich varian t of Ki-1 ALCL exists, expanding the morphological spectrum of this tu mour.