Clinical, Phenotypic, and Genetic Characteristics of Non-CLL Type Monoclonal B Lymphocytosis (MBL)
Bibliographic record
Abstract
Abstract Abstract 5209 Monoclonal B-cell lymphocytosis (MBL) has been established as a diagnostic category to denote the finding of clonal B lymphocytes in otherwise healthy and asymptomatic individuals. MBL likely represents early lesions in lymphoid neoplasms. Immunophenotypically, MBL is divided into CD5+ CLL-type and CD5- non-CLL type MBL, respectively. While most studies have focused on CLL-type MBL and provided evidence of progression of MBL to clinical CLL, the biological nature and clinical relevance of non-CLL type MBL remain unclear. In this study, we have identified and evaluated a series of 18 patients with non-CLL type MBL. This group comprised 10 males and 8 females with a median age of 74 years (range 53–95). All the patients presented initially with a mild to moderate absolute lymphocytosis. Clinical and laboratory evaluations were performed with a follow-up period of 1–20 years (median 8.5). Clonal B lymphocyte populations were confirmed by flow cytometry analysis. All the MBL clones showed negative for CD5, CD10 and CD103, positive for CD19 and CD20, and heterogeneous for CD23, CD25, CD79b, FMC7 and CD38. The phenotypic findings excluded CLL, mantle cell lymphoma and hairy cell leukemia, but may overlap with marginal zone lymphoma or lymphoplasmacytic lymphoma. Cytogenetics were available for 9 patients. Of the cytogenetic abnormalities, 7q deletion was found in two clones, 17 q deletion in two other clones, 11q deletion in one clone and t(2;7) in another clone. An overall tendency was shown toward clonal expansion with an increase in absolute lymphocyte count (ALC) over time (initial mean ALC of 4.9 ± 0.46 × 109/L to a recent mean ALC of 8.3 ± 2.18 × 109/L, p = 0.151). Three patients had an initial ALC >8 × 109/L which remained stable in one patient and decreased to <6 × 109/L in 2 patients. The patient with the longest follow-up of 20 years underwent a completely benign course, while the CD5- clonal B cell population was persistent but non-progressing. Of the progressive clones, three patients had an increase in ALC >10 × 109/L; one patient's ALC progressed over a period of 9 years to 35 × 109/L that required treatment. Clinically, three patients developed splenomegaly and one patient progressed with lymphadenopathy. Unlike the findings from population screening, this study represents a series of clinical MBL of non-CLL phenotype, and our results indicate the heterogeneity in genetic changes and clonal progression. Disclosures: No relevant conflicts of interest to declare.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".