A 68-year-old male with a history of chronic lymphocytic leukemia presents for follow-up with his oncologist. On review of symptoms the patient reports worsening fatigue and a recent fever that has persisted for one weeks' duration. He denies sick contacts, weight loss, or night sweats. Physical examination reveals enlarged, fixed axillary and abdominal lymph nodes. Lymph node biopsy reveals a monotonous infiltrate of small lymphocytes on one side with a pattern of diffuse large cells on the right.
The most likely explanation for these findings is
- acute myelogenous leukemia
- benign leukemoid reaction
- infectious mononucleosis
- progressive chronic lymphocytic leukemia
- Richter's transformation