Study: Body Fat Composition May Predict Poor Treatment Outcomes in Patients With Multiple Myeloma

While studies have demonstrated that excess body weight is a risk factor for both the incidence and mortality of multiple myeloma (MM), to date, the correlation between body fat composition and disease activity, adverse events, and treatment response has not been well investigated. A recent study, published in Oncotarget, found that excess body fat in the abdomen and pelvis may predict poor treatment response in patients with MM.

The study followed a subgroup of 108 patients with MM who were enrolled in the prospective GMMG-MM5 trial. The patients received whole-body low-dose computed tomography (WBLDCT) that measured body fat composition prior to induction therapy.

In each patient, body fat was divided into the areas of abdomen, pelvis, and thigh. Total adipose tissue (TAT) was categorized as either subcutaneous (SAT) or visceral (VAT). The researchers assessed the relationship between these body fat parameters and disease activity, cytogenetics, adverse events, and treatment response.

The researchers found that baseline hemoglobin levels correlated significantly with abdominal TAT and VAT, as well as with abdominal VAT. Furthermore, a significant correlation was found between osteopenia and abdominal TAT and SAT, as well as with pelvic TAT. Finally, a reciprocal correlation was observed between adverse cytogenetics and abdominal and pelvic VAT.

In terms of treatment outcomes, 42 patients achieved a very good partial response (VGPR) or better, while 55 patients reached a partial response (PR) or worse. Treatment response was negatively correlated to abdominal and pelvic VAT. In contrast to body fat composition, body mass index did not show a significant association with treatment response.

The researchers did not identify a correlation between body fat parameters and disease activity; calcium, renal, anemia, and bone (CRAB) criteria; or adverse events.

The researchers concluded that there was a clinically relevant difference in the treatment outcomes of patients depending upon VAT and SAT, and that excessive body fat in the pelvis could be a predictive factor for poor treatment response. Further studies are necessary, they say, in order to investigate this apparent relationship and to assess the role of weight gain or loss over the course of treatment for MM. Additional influences that warrant further investigation, according to the study, include comorbidities, chemotherapy dosing, and the interaction of drugs with body fat metabolism.