Varied manifestations of a familial lymphoproliferative disorder.

In a sibship of nine adults, four died of lymphocytic or histiocytic lymphomas, and one of Waldenström's macroglobulinemia (immunoglobulin M [IgM], kappa type) complicated by adenocarcinoma of the lung. In the next generation, one member died of Hodgkin's disease; four of nine healthy persons had impaired lymphocyte transformation in vitro in response to phytohemagglutinin-P (PHA-P), and three of these had polyclonal elevations in IgM levels. Subsequent to these observations, adenocarcinoma of the lung developed in one woman with immune defects, and lymphocytic leukemia developed in her 3 year old grandson. The findings in this family point to a genetically regulated defect of immunity expressed as diverse lymphoproliferative disorders, including polyclonal and monoclonal IgM gammopathies. The occurrence of pulmonary adenocarcinoma in two members suggests genetic and immunologic determinants in these instances.