DENDRITIC CELL TUMORS ASSOCIATED WITH LOW-GRADE B-CELL MALIGNANCIES -REPORT OF 3 CASES

Indeterminate and interdigitating cell tumors are rare proliferations of immunoregulatory cells that demonstrate morphologic, immunologic, a nd ultrastructural features similar to their cells of origin. Although an association of lymphoproliferative disease with Langerhans' cell h istiocytosis is well described, only sporadic cases of non-Langerhans' dendritic cell proliferations have been published. The authors descri be three patients with low grade B-cell lymphoproliferative disease wh o developed subsequent indeterminate cell or interdigitating cell tumo rs. When the two cases of indeterminate cell tumor are added to those previously described in the literature, it appears that 4 of 13 cases (31%) are associated with a history of low grade B-cell malignancy. Po ssible explanations for the relationship between these two disorders a re discussed.