Prolymphocytic leukemia: clinical, histopathological, and cytochemical observations.

The clinical, histopathological, and cytochemical features of eight patients with prolymphocytic leukemia, a rare variant of chronic lymphocytic leukemia, were reviewed. Six of the patients had clinical evidence of "massive" splenomegaly at the time of diagnosis, and in four of these this clinical impression was confirmed by splenic weights in excess of 2000 g. No patient had significant lymph node enlargement. The initial leukocyte count was elevated in seven patients and was greater than 100 X 10(9)/1 in four of them. The absolute prolymphocyte count ranged from 16.3 to 378.1 X 10(9)/1 and was greater than 100 X 10(9)/1 in four patients. Splenectomy in four patients had no lasting effect on the peripheral leukocyte count. In the four patients in whom the disease was shown by surface marker or immunocytochemical studies to be of B-cell origin, the histopathologic features were distinctive and were characterized by a pattern of infiltration which was nodular and diffuse in both the splenic red pulp and the bone marrow, whereas involvement of the lymph nodes was pseudonodular. In one patient in whom the prolymphocytes had cytochemical characteristics suggestive of T-cells, the distribution of the abnormal cellular proliferation in the lymph nodes was paracortical and the infiltrations of the spleen and the bone marrow were diffuse.