Table 1.
Required and Recommended Markers for Use in the Diagnosis of CLL with Reagent Specification Based on Expression Patterns in Normal Peripheral Blood.
| Control population in normal peripheral blood | Minimum relative fluorescence intensity of positive and negative control | ||||
|---|---|---|---|---|---|
| Inclusion in diagnostic panel | Antigen | Expression in CLL (% pos vs. control) | Positive | Negative | populations (preferred) |
| Required | CD19 | Positive (>95%) | CD20+ B‐cells | CD3+ T‐cells | ≥10a |
| CD5 | Positive (>20%) | CD3+ T‐cells | CD19+ B‐cells | ≥30 (≥65) | |
| CD23 | Positive (>20%) | CD23+ B‐cells | T‐cells | ≥5a | |
| CD20 | Weak | CD19+ B‐cells | CD3+ T‐cells | ≥10 (≥20) | |
| Igκ Igλ | Weak & restricted | CD20+ B‐cells | CD3+ T‐cells | ≥5a | |
| Recommended | CD43 | Positive (>20%) | CD3+ T‐cells | CD20+ B‐cells | ≥15 (≥40) |
| CD79b | Weak | CD20+ B‐cells | CD3+ T‐cells | ≥15 (≥30) | |
| CD81 | Weak | CD3+ T‐cells | Granulocytes | ≥12 (≥20) | |
| CD200 | Positive (>20%) | CD19+ B‐cells | CD3+ T‐cells | ≥5a | |
| CD10 | Negative (<20%) | Granulocytes | T‐cells | ≥10a | |
| ROR1 | Positive (>20%) | B‐progenitors | T‐cells | ≥5a | |
Required, consensus from >75% of participants. Recommended, consensus from >50% of participants with the following exceptions determined by the steering committee and confirmed by further consensus: exclusion of FMC7 (epitope of CD20) 15, CD38 & CD45 (used for prognostic information and gating orientation but not specifically required for diagnosis), and inclusion of ROR1 which is closely associated with CLL 9, 10 but diagnostic antibodies were not widely available at the time of the survey.
Definition of weak: median fluorescence intensity at least 20% [identified as the minimum measurable difference based on ICSH/ISLH guideline recommendations for acceptable variation due to assay imprecision and specimen stability 14] lower than the median expression level by normal peripheral blood B‐cells. Each laboratory was requested to determine their own reference range.
Specifically validated otherwise consensus, defined as approval of all contributing authors with no disagreement on open consultation by ERIC/ESCCA members. Values refer to the relative signal on positive versus negative control populations required to achieve optimal separation of CLL cells from normal B‐cells 13.