CLL immunophenotypic score (Matutes score)

Immunophenotypic score for diagnosis of chronic lymphocytic leukemia

Flow cytometric analysis of peripheral blood or bone marrow is performed for expression of the cell surface markers listed in the table below. The scores for each marker are summed.

A score ≥ 4 is indicative of CLL. A score of ≤ 3 should prompt consideration of an alternative diagnosis.

Cell surface marker0 points1 point
CD79b (or CD22)StrongWeak
CD23NegativePositive
CD5NegativePositive
FMC7PositiveNegative
SmIgStrongWeak
Adapted from Matutes et al, 19941 and Moreau et al, 1997.2

The original version of this immunophenotypic scoring system for chronic lymphocytic leukemia (CLL), also known as the CLL score or Matutes score, was published in 1994.1 A modification of the scoring system, substituting CD22 with CD79b, was proposed in 1997.2

FMC7: an antibody clone identifying an epitope of CD20
SmIg: surface membrane immunoglobulin