Cytogenetic, Cytophotometric, and Ultrastructural Study of Large Cerebriform Cells of the Sézary Syndrome and Description of a Small-Cell Variant23

Abstract

Ultrastrudural, cytophotometric, and cytogenetic studies were performed on 4 patients with Sézary syndrome. The diagnosis of Sézary syndrome was based on the association of skin manifestations with the presence in the blood of an abnormal cell exhibiting a high nucleocytoplasmic ratio, a grooved and folded nucleus, and peroxidase and nonspecific esterase negativity. Twelve patients were used as controls: 1 with monocytic leukemia, 6 with chronic lymphocytic leukemia (CLL), 2 healthy donors, and 3 patients with other skin diseases. Two types of abnormal cells were recognized: 1) a large-cell type with a serpentine and cerebriform nucleus, near-tetraploid DNA values, and near-tetraploid chromosome counts and 2) a small-cell variant with indented nucleus, diploid DNA values,and pseudodiploid or hyperdiploid chromosome counts. Among others, A and B as well as Gq— markers were found. It was concluded that chromosomal abnormalities represent an additional criterion for the characterization of the Sézary cell, the nature of which appears to be lymphocytic because of itsresponse in culture to phytohemagglutinin. In addition, preliminary immunologic studies indicated that the Sézary cell is not a B-lymphocyte. It was hypothesized that Sézary syndrome is an uncommon thymus-derived form of CLL.