CHILDHOOD ANAPLASTIC LARGE-CELL LYMPHOMA KI-1 CD30 - CLINICOPATHOLOGICAL FEATURES OF 19 CASES

The authors report their cumulative experience of 19 children with wha t was previously called malignant histiocytosis (MH) but is now consid ered a true lymphoma and termed anaplastic large cell lymphoma (ALCL). The median age at diagnosis was 10 years and 6 months (range 2 y, 11 m, to 15 y). There were 13 males and 6 females. Most cases presented w ith fever, wasting and enlarged, often tender, lymph nodes. Other feat ures were: fleeting cutaneous rashes in 7 cases; spontaneous regressio n of lymph nodes and skin lesions were seen in 5 patients. Bone marrow involvement was present in 3 cases, pulmonary infiltrate in 5, kidney s in 2, and central nervous system in none. The morphology of lymph no de involvement was consistent with so-called MH, a description origina lly applied to sinusoidal infiltration by large 'histiocytic'' cells. The coexpression of lymphoid activation antigens Ki-1/CD 30 (18/19), e pithelial membrane antigen EMA (18/19) and interleukin-2 receptor/CD 2 5 (10/10) was the unifying immunopathologic feature of the neoplasm. L ineage antigens were not identifiable in 8/19 instances (null phenotyp e), while 10/19 expressed a T-cell phenotype. None of the tumors expre ssed histiocytic markers. After variable, but intensive, combination c hemotherapy, 15 children out of 18 evaluable achieved complete remissi on (CR). Among all patients, thirteen are still alive in CR (ten in fi rst CR) with a median follow-up of 5 years. This evaluation in the ped iatric age group reinforces that so-called MH is a lymphoid neoplasm, a conceptual change that could lead to improved understanding and ther apy. (C) 1994 Wiley-Liss, Inc.