Beta-2 Microglobulin in Follicular Lymphoma

Role in Prognostic Scoring Systems

The European Society for Medical Oncology (ESMO) guidelines incorporate Beta-2 microglobulin (B2M) as a critical prognostic marker in follicular lymphoma, which independently predicts survival outcomes and is part of validated prognostic scoring systems, such as FLIPI 2 and PRIMA-PI, in patients with follicular lymphoma 1, 2, 3
B2M is a core component of the FLIPI 2 index, which includes elevated B2M as one of five risk factors, stratifying patients into low-risk, intermediate-risk, and high-risk categories, and is used to guide treatment decisions in patients with follicular lymphoma 1, 2, 3
The PRIMA-PI uses B2M as the primary stratification tool, with low-risk patients having normal B2M without bone marrow involvement, intermediate-risk having normal B2M with bone marrow involvement, and high-risk having elevated B2M, regardless of bone marrow status, in patients with follicular lymphoma 1, 2, 3, 4

Elevated B2M indicates high tumor burden and triggers treatment initiation, even in asymptomatic patients, as it is included among the high tumor burden criteria that mandate starting systemic therapy in patients with follicular lymphoma 1, 2, 4, 5, 6

The European Society for Medical Oncology (ESMO) guidelines recommend measuring B2M at diagnosis, alongside complete blood count, LDH, uric acid, and immunoglobulin levels, as part of the standard initial laboratory assessment in patients with follicular lymphoma 7, 8
B2M measurement is essential for calculating FLIPI 2 and PRIMA-PI scores, which guide treatment intensity decisions in patients with follicular lymphoma 1, 2, 3