Sarcopenia and adiposity measures are significantly prognostic among patients with nonmetastatic breast cancer and may help determine effective management strategies, according to a study published in JAMA Oncology.1
The most commonly used measure to help understand the association between cancer outcomes and body composition is body mass index (BMI), but significant shortcomings — such as the failure to take into consideration muscle content and adiposity — have led to mixed results when assessing survival among this patient population. Previous studies have demonstrated that sarcopenia, poor muscle quality, and excess adiposity (as determined by computed tomography [CT] scans) are associated with higher mortality, but their prognostic value for cancer outcomes is not fully understood.
For this retrospective, observational study, researchers collected data of 3241 women with stage II or III breast cancer diagnosed between January 2000 and December 2013 from 2 different cancer centers. Eligible patients had a valid weight at time of CT, readable CT results, and a BMI higher than 18.5. The median follow-up was 6 years.
Analysis showed that 1086 (34%) and 1199 (37%) patients had sarcopenia and low muscle radiodensity, respectively.
Patients with sarcopenia had a higher overall mortality compared with patients without sarcopenia (hazard ratio [HR], 1.41; 95% CI, 1.18-1.69), and patients in the highest tertile of total adipose tissue also had a higher overall mortality compared with the lowest tertile (HR, 1.35; 95% CI, 1.08-1.69).
Among study patients, those with sarcopenia and the highest levels of total adipose tissue had the highest level of mortality (HR, 1.89; 95% CI, 1.30-2.73).
No associations between mortality and low muscle radiodensity were observed. There were no significant correlations between BMI and overall mortality and BMI did not have any prognostic value for death when considering body composition.
The authors concluded that “both muscle and adiposity represent modifiable risk factors in patients with breast cancer. In addition to weight loss, we should also consider interventions to improve muscle mass, such as resistance training or protein supplementation. In the era of precision medicine, the direct measurement of muscle and adiposity will help to guide treatment plans and interventions to optimize survival outcomes.”
- Caan BJ, Cespedes Feliciano EM, Prado CM, et al. Assocation of muscle and adiposity measured by computed tomography with survival in patients with nonmetastatic breast cancer [published online April 5, 2018]. JAMA Oncol. doi: 10.1001/jamaoncol.2018.0137