Clinical Laboratory Hematology 3rd Edition by Shirlyn McKenzie, Lynne Williams

Exercise 11

Francine, a 10-year-old female, was brought to her pediatrician for complaints of lethargy and leg pain. Physical examination revealed splenomegaly and lymphadenopathy. A complete blood count was ordered with the following results:
platelets
Refer to the tables on the front inside cover of the book and determine which blood cell parameters, if any, are abnormal.
Microscopic examination of a stained blood smear from Francine revealed a predominance of very young blood cells (blasts) in the peripheral blood. These cells are normally found only in the bone marrow. Subsequently, she had bone marrow aspirated for examination. This revealed 100% cellularity (red marrow) with a predominance of the same type of blasts as those found in the peripheral blood.
Francine had lymphadenopathy. The leukemia was diagnosed as a leukemia of lymphocytic cells.
What might explain the lymphadenopathy?