I requested quantitative reports from Beth Israel Deaconnes Medical Center in Boston where the diagnosis was done last summer. They were waiting for me when I returned from Canada and I discovered some answers to some questions:
- The bone marrow biopsy/aspirate showed 33% lymphocytes -- that answers the "small clonal population" question as according to MD Anderson, "lymphocytes >30% are diagnostic for CLL.
- The flow cytometry studies showed the "presence of a Kappa restricted CD20 dim, CD23+, CD5 B-cell population that is immunophenotypically consistent with involvement by chronic lymphocytic leukemia/small cell lymphocytic lymphoma."
- CD38 expression is not detected (and that is a good thing!!!!)
- CD5+ B-cells express ZAP-70 (not a good thing ---- but ---- it could be a lab error)
- Molecular cytogenetic - four DNA probes -- all in normal ranges (another good thing)
So here is what I now understand: CLL and SLL are biologically and morphologically the same disease but present differently: CLL in the blood and SLL in the lymphatic system.