In a retrospective hospital-based cohort study from the Mayo Clinic, Shanafelt et al.(19) explored the outcome of patients with CLL-like MBL relative to that of individuals with Rai stage 0 CLL. Using hematopathology records, the authors were able to identify 631 patients with newly diagnosed MBL or Rai stage 0 CLL. Within this cohort, 302 patients fulfilled the criteria for diagnosis of MBL (B-cell counts of 0.02 to 4.99 x 109/L); and 313 Rai stage 0 CLL (94 patients had Rai stage 0 CLL with an ALC ≤10 x 109/L; 219 patients had Rai stage 0 CLL with an ALC >10 x 109/L). Clinical information regarding date of diagnosis, physical examination, prognostic parameters, treatment history, and disease-relatedcomplications were abstracted from clinical records.
