Examination of a peripheral blood smear demonstrates leukemia composed of small mature lymphocytes without blast forms. Which of the following is the most likely age of this patient?: (A) 1 year, (B) 20 years, (C) 45 years, (D) 65 years
Answer is D. The disease described is chronic lymphocytic leukemia (CLL), which is a disease of older adults. The 1 year-old (choice A) would be most likely to have acute lymphocytic leukemia (ALL). The 45 year-old (choice C) would be likely to have either AML or chronic myelogenous leukemia (CML).