Chronic lymphocytic leukemia (CLL), haematological described since the early nineteenth century, is considered a haematological indolence, but of-a-time there was found that its evolution can be extremely varied.
Most of the patients were over 60 years at the time the diagnosis was established, and this may be due to decreased immune competence with age. Males are affected 2 times more frequently than the female, the male percentage: female being 2:1. Fewer than 10% of cases occur in adults and in children below 40 years old have been few reported cases of CLL. (1.2)