In Barcelona in late 2018, at the 1st International ERIC meeting, there was much talk about MBL or Monoclonal B-cell Lymphocytosis, a possible precursor to CLL.
I asked Dr. John Seymour of the PeterMac in Melbourne, Australia to explain the basic concepts.
- All cancer including CLL is clonal, in other worlds it is made up of identical cells.
- If one has ≥5,000 monoclonal B-cells that are typical of CLL, then chronic lymphocytic leukemia can be diagnosed.
- If one has < 5,000 the diagnosis is MBL or Monoclonal B-cell Lymphocytosis.
- The clonal cells in both diagnoses are the same and the 5,000 value is admittedly arbitrary.
- MBL consist of two groups:
- Low-count MBL has bloodB-cell counts <0.5x9 cells/liter.
- High-count MBL has bloodB-cell counts ≥0.5x9/L but <5×109/L.
- Low-count MBL does not progress to a malignant disease.
- High-count MBL does at a rate of 1-2% per year.
- Both MBL and CLL patients have impaired immunity that puts us at a higher risk for infections and cancer.
- Even when diagnosed with CLL, many of us can have a normal life expectancy.
Please enjoy my interview from ERIC 2018 with Dr. John Seymour.
For more on MBL from Dr. Neil Kay of Mayo please see this interview from ASH 2016 that tells some of the backstory of how MBL was first recognized: https://cllsociety.org/2017/06/mbl-precursor-cll/
Here is a 2015 lecture that Dr. Kay gave on MBL and early care in CLL: https://cllsociety.org/2015/07/crc-2015-dr-neil-kay-on-prognostic-indicators-and-standard-early-care-for-cll-chronic-lymphocytic-leukemia/
Thanks for watching and reading.
Brian Koffman MDCM (retired)