ABSTRACT
Prolymphocytic leukemias (PLLs) of B-and T-cell subtype are rare diseases, which
together account for around 2% of all mature lymphoid leukemias. When first described
in the 1970s (1), the different cells of origin were not appreciated, and the disease was
called a variant of chronic lymphocytic leukemia (CLL). Advances in immunophenotyp-
ing and molecular cytogenetics have significantly contributed to a more precise
classification of the mature lymphoid leukemias, and this has resulted in better
management of patients with these conditions. Recent studies have highlighted the role of
specific oncogenes such as TCL1, MTCP-1, and ATM in T-cell prolymphocytic leukemia
(T-PLL) and TP53 mutations in the case of B-cell prolymphocytic leukemia (B-PLL).
However, despite better understanding of the underlying cell biology, prognosis for these
patients remains poor with no curative therapy and shortened survival. The advent of
monoclonal antibody therapy and the wider application of nonmyeloablative allogeneic
transplantation have increased the treatment options for this group of patients. Table 1
summarizes the characteristic features of the PLLs.
