Blood: Progression and prognosis of monoclonal B lymphocytosis

Monoclonal B-cell lymphocytosis (MBL) is a common hematologic precancerous lesion that has not been well studied
in screening cohorts.
According to the size of the B cell clones, MBL can be divided into low count (LC) and high count (HC) types
.

Through the Mayo Clinic Biobank, researchers such as Susan L.
Slager screen MBL cases and assess their correlation
with future hematological malignancies and overall survival (OS).

This is a two-phase study design that includes a discovery and validation cohort
.
The researchers used eight-color flow cytometry to detect MBL
.
Medical records
to screen for hematological malignancies and deaths.
Cox regression was used to assess correlation, estimating risk ratios and 95% confidence intervals (CI), adjusted
for age and sex.

The incidence of MBL

A total of 1712 (17%) MBL (95% LC-MBL) were identified, with a median follow-up of 34.
4 months and 621 patients died
.
An association with OS was not observed in patients with LC-MBL (P=0.
78), but was associated in patients with HC-MBL (HR 1.
8, 95% CI 1.
3-3.
1, P=0.
03).

Incidence of hematological malignancies and malignancies of the lymphatic system

In the discovery cohort, with a median follow-up of 10.
0 years, 31 people developed hematologic cancers, two-thirds of which were lymphatic malignancies
.
Compared with controls, MBL was associated with a 3.
6-fold increased risk of hematological malignancies (95% CI 1.
7-7.
7, P<0.
001) and a 7.
7-fold increased risk of lymphatic malignancies (95% CI 3.
1-19.
2, P<0.
001).

。 LC-MBL was associated with a 4.
3-fold increased risk of lymphatic malignancy (95% CI 1.
4-12.
7; P=0.
009); Patients with HC-MBL had a 74-fold increased risk of lymphatic malignancy (95% CI 22-246, P<0.
001)!

In summary, the results of this large-scale screening cohort showed that the survival rate of LC-MBL patients and non-LC-MBL patients was similar, but the risk of lymphatic malignancy in LC-MBL patients was increased by 4 times
.
There is increasing evidence that LC-MBL has an impact
on clinical outcomes.

Original source:

Susan L.
Slager, et al.
Progression and survival of MBL: a screening study of 10?139 individuals.
Blood (2022) 140 (15): 1702–1709.
https://doi.
org/10.
1182/blood.
2022016279