A 60-year-old man is referred because of splenomegaly and generalized lymphadenopathy. The total white blood cell count is markedly elevated, and the differential count reveals a preponderance of mature appearing lymphocytes. Bone marrow examination reveals a diffuse infiltration with similar-appearing lymphocytes. Which of the following statements best characterizes this disorder?
High-Yield Explanation
The diagnosis is CLL. Hypogammaglobulinemia may occur early in the course of the disease, leading to frequent bacterial infections. The mean survival is 3 to 7 years after diagnosis, although much longer symptom-free survivals are quite common. CLL is characterized by a proliferation of neoplastic mature lymphoid cells, which are almost always B cells.