Molecular, phenotypic, and clinical characteristics of the Ig V gene-defined B-cell chronic lymphocytic leukemia (B-CLL) subgroups.*
| . | Subgroup I . | Subgroup II . |
|---|---|---|
| * Subgroup I is defined by the expression of unmutated (< 2% difference from germline counterpart) BCRs, and Subgroup II by the expression of mutated (≥ 2% difference from germ line) BCRs. Patients in Subgroup I experience a much more aggressive clinical course. | ||
| Abbreviations: Ig, immunoglobulin; BCR, B-cell receptor. | ||
| Stage at presentation | Often Rai intermediate/high risk | Often Rai low risk |
| Age at presentation | No difference | No difference |
| Gender | More males | M = F |
| Lymphocyte doubling time | Frequently < 12 months | Frequently > 12 months |
| V gene mutations | Few or none | Significant numbers |
| Antigen selection | Yes | Yes |
| ZAP70 expression | High | Low |
| CD38 expression | High | Low |
| Activation markers | 38+/69+ | 71+/62L+ |
| Telomere length | Uniformly short | Diverse lengths |
| Telomerase activity | High | Low |
| Retention of BCR signaling | Yes | No |
| Ongoing Ig V gene mutations | Yes | Yes |
| Intermittent expression of AID | Yes | Yes |
| Chromosomal abnormalities | Poor prognosis | Better prognosis |
| Treatment requirement | Usual | Unusual |
| . | Subgroup I . | Subgroup II . |
|---|---|---|
| * Subgroup I is defined by the expression of unmutated (< 2% difference from germline counterpart) BCRs, and Subgroup II by the expression of mutated (≥ 2% difference from germ line) BCRs. Patients in Subgroup I experience a much more aggressive clinical course. | ||
| Abbreviations: Ig, immunoglobulin; BCR, B-cell receptor. | ||
| Stage at presentation | Often Rai intermediate/high risk | Often Rai low risk |
| Age at presentation | No difference | No difference |
| Gender | More males | M = F |
| Lymphocyte doubling time | Frequently < 12 months | Frequently > 12 months |
| V gene mutations | Few or none | Significant numbers |
| Antigen selection | Yes | Yes |
| ZAP70 expression | High | Low |
| CD38 expression | High | Low |
| Activation markers | 38+/69+ | 71+/62L+ |
| Telomere length | Uniformly short | Diverse lengths |
| Telomerase activity | High | Low |
| Retention of BCR signaling | Yes | No |
| Ongoing Ig V gene mutations | Yes | Yes |
| Intermittent expression of AID | Yes | Yes |
| Chromosomal abnormalities | Poor prognosis | Better prognosis |
| Treatment requirement | Usual | Unusual |