Concept
B-cell prolymphocytic leukemia, referred to as B-PLL, is a rare blood cancer. It is a more aggressive, but still treatable, form of leukemia. Specifically, B-PLL is a prolymphocytic leukemia (PLL) that affects prolymphocytes – immature forms of B-lymphocytes and T-lymphocytes – in the peripheral blood, bone marrow, and spleen. It is an aggressive cancer that presents poor response to treatment. Mature lymphocytes are infection-fighting immune system cells. B-lymphocytes have two responsibilities: Production of antibodies – In response to antigens, B-lymphocytes produce and release antibodies specific to foreign substances in order to aid in their identification and elimination phagocytes Generation of memory cells – Interactions between antibodies and antigens allow B-lymphocytes to establish cellular memories, otherwise known as immunities that allow the body to respond more rapidly and efficiently to previously encountered species It is categorized as a lymphoproliferative disorder due to the excessive production of lymphocytes, in B-PLL there is excess production of B-prolymphocytes by the bone marrow. These immature lymphocytes are not normally found in the blood; part of their maturation process is being programmed to produce antibodies against foreign material prior to their departure from the bone marrow. In B-PLL, malignant B-prolymphocytes disrupt the adaptive capabilities of the immune system due to the lack of mature B-lymphocytes. It has been suggested that some cases may represent a variant of mantle cell lymphoma. This type of leukemia is characterized by: More than 55% of circulating cells in peripheral blood (red blood cells, white blood cells and platelets collectively) are prolymphocytes. Generally, prolymphocyte proportion exceeds 90% Minimal or absence of lymphadenopathy – abnormalities in size, number or consistency of lymph nodes Splenomegaly - Abnormal enlargement of the spleen High white blood cell count B-symptoms – Fever, night sweats and/or weight loss Similar to other leukemias, B-cell prolymphocytic leukemia is often asymptomatic.
