Features of prolymphocytes
(1) medium-sized (about twice the size of a mature lymphocyte)
(2) prominent nucleolus
(3) moderately condensed nuclear chromatin
(4) faintly basophilic cytoplasm
Clinical features of CLL/PL:
(1) typically an older male
(2) presence of systemic symptoms
(3) massive splenomegaly
(4) no or limited lymphadenopathy
(5) poor prognosis
Laboratory findings:
(1) increasing white blood cell count with a large percent of prolymphocytes
(1a) CLL with increased prolymphocytes (percent 10 to 55%)
(1b) CLL with prolymphocytic transformation (percent > 55%)
(2) bone marrow involvement with anemia and thrombocytopenia
(3) complex cytogenetic abnormalities, especially c-myc gene alterations such as t(8;14) and t(8;22).
(4) B cell markers (if B-PL) with
(4a) positive CD19, CD20, CD22, CD79a, and FMC7
(4b) negative CD23
Differential diagnosis:
(1) mantle cell leukemia