The clinical, morphological, immunologic, and cytogenetic features of seven cases of chronic granulated T cell
lymphocytosis with
neutropenia were studied. The disorder was characterized by moderate blood and bone marrow
lymphocytosis,
neutropenia, polyclonal
hypergammaglobulinemia,
splenomegaly, absence of
lymphadenopathy, and a chronic, relatively stable
clinical course. The proliferative lymphocytes manifested a cytotoxic/suppressor T lymphocyte phenotype. In two of four cases studied, blood lymphocytes showed clonal
chromosome abnormalities. One patient treated with pulse
steroid therapy had reversal of
lymphocytosis and severe
neutropenia with subsequent resolution of an intractable
infection. The
lymphocytosis and
neutropenia recurred when
steroids were withdrawn. Six of the seven patients were living three months to 17 years from diagnosis; one died at 4.3 years of an unrelated cause. Five of the patients, including the two with lymphocyte
chromosome abnormalities, had persistent
lymphocytosis and
neutropenia from three months to 13 years from diagnosis. In two patients, the disease appears to have undergone
spontaneous regression. No differences in clinical presentation or the morphological or immunologic characteristics of the proliferative lymphocytes were apparent between those patients with lymphocyte
chromosome abnormalities and persistent disease and those who had a
spontaneous regression. The finding of clonal
chromosome abnormalities in the blood lymphocytes of two of the patients in this study suggests a neoplastic origin for chronic granulated T cell
lymphocytosis with
neutropenia. However, apparent
spontaneous regression in two patients, one after 11 years, lends support to a chronic reactive or immunoregulatory disorder as the etiology. It is probable that cases of granulated T cell
lymphocytosis with
neutropenia, although morphologically and immunologically similar, are biologically heterogeneous.