B-cell chronic lymphocytic leukemia: recent progress in biology, diagnosis, and therapy.

B-cell chronic lymphocytic leukemia (CLL) is a highly common form of leukemia characterized by the accumulation of long-lived, functionally inactive, mature appearing neoplastic B lymphocytes. In addition, immune disturbances such as hypogammaglobulinemia and autoimmune phenomena (particularly, autoimmune hemolytic anemia) are frequently found in CLL patients [1-2]. The etiology of CLL is unknown. In contrast with other leukemias, there is no relationship between CLL and exposure to radiation or other cytotoxic agents. A genetic basis is highly likely since there are differences in the incidence of CLL in different countries (e.g., CLL accounts for 30%-40% of all the leukemias in Western countries as compared to 5%-10% in Asian countries) and the risk of contracting CLL is higher among persons with first-degree relatives with the disease [3]. Because the incidence of CLL increases with age and the longer life expectancy of the general population, the age of patients at diagnosis is increasing. The median age at diagnosis is now about 70 years, with only one-third of the patients being less than 60 years of age. In the majority of the series, males predominate over females in a proportion of 1.5/1. The prognosis of patients with CLL is variable. However, clinical stages and other prognostic factors allow the individual risk of each patient to be assessed very accurately, which is useful for making treatment decisions. In the past two decades, significant progress has been made in CLL [4-10]. This review summarizes recent advances in the biology, diagnosis, and therapy of CLL.