Plasma Cell Disorder Family History Linked to Longer OS in MM

Having a family history of plasma cell disorders (PCD) was associated with improved overall survival among patients with monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma (MM), and systemic light chain (AL) amyloidosis, according to a recent study.

“Previous studies have focused on characterizing the prevalence of PCD’s amongst family members of PCD patients and the determinants of heritability, however the question of whether a PCD family history affects a patient’s prognosis has not been well studied,” study researchers wrote.

Therefore, the researchers conducted a retrospective study of outcomes of 25,423 patients with MGUS, MM, or AL amyloidosis. Of these, 2.7% of patients reported having a family member with a PCD. This family history was documented in the medical record of 94% of patients with MGUS, 92% of patients with MM, and 88% of patient with AL amyloidosis.

A review of outcomes showed that overall survival was consistently longer in patients with compared with without a familial PCD. The crude hazard ratio (HR) for MGUS was 0.52 (P<0.001), for MM was 0.68 (P<0.001), and for AL amyloidosis was 0.60 (P=0.003).

According to the researchers, this association with family history remained even after adjustment for baseline patient and disease characteristics.

“While we cannot completely exclude all biases in this study, we believe that the consistency of our results suggests that the association between family history of PCD and improved survival is a robust finding,” the researchers wrote.

However, the study also demonstrated that among patients with MGUS, the risk of progression to MM, AL amyloidosis, or a lymphoproliferative disorders was higher in those with a family PCD history when accounting for death as a competing risk (HR=1.9; P<0.001).

“Though our study suggests that a PCD family history may increase risk of disease progression, at present there are no data to suggest that screening for MGUS improves health outcomes,” the researchers wrote. “While early intervention trials in smoldering MM have shown a progression free survival benefit with anti-plasma cell therapy compared to observation, these data are not generalizable to MGUS patients given the lower risk of disease progression.”