Obesity and black race are associated with an increased risk for transformation of monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma, according to a retrospective study published in the Journal of the National Cancer Institute.1

Multiple myeloma is 1 of the most common hematologic malignancies in the United States and is frequently preceded by MGUS, an asymptomatic plasma cell neoplasm involving an excess of M protein.

To investigate the role of obesity in the progression of MGUS to multiple myeloma, researchers analyzed data from 7878 patients with MGUS included in the US Veterans Health Administration database. Of those, 39.8% were overweight, 33.8% were obese, and 64.1% were white.

During a median follow-up of 68 months, 329 (4.2%) patients with MGUS progressed to multiple myeloma, including 72 (3.5%) normal-weight patients, 144 (4.6%) overweight patients, and 113 (4.3%) obese patients.

After adjusting for multiple variables, researchers found that obese patients had a nearly 2 times higher risk for progressing to multiple myeloma than normal-weight patients (hazard ratio [HR], 1.98; 95% CI, 1.47-2.68). In addition, overweight patients had a 55% increased risk for transforming to multiple myeloma compared with normal-weight patients (HR, 1.55; 95% CI, 1.16-2.06).

Moreover, results showed that black race was associated with an approximately 2 times increased risk for progression from MGUS to multiple myeloma (HR, 1.98; 95% CI, 1.55-2.54).

These findings may ultimately help to guide clinicians in the risk stratification and management of patients with MGUS. Future clinical trials should investigate whether weight loss is an effective strategy for reducing the risk of multiple myeloma progression in this population.

Reference

1. Chang S-H, Luo S, Thomas TS, et al. Obesity and the transformation of monoclonal gammopathy of undetermined significance to multiple myeloma: A population-based cohort study. J Natl Cancer Inst. 2016 Dec 31. doi: 10.1093/jnci.djw264. [Epub ahead of print]