Muscle and cancer - It is not getting old that is the problem, it is getting weaker!

I saw this get picked up in a few places but no one was linking to the actual study.  The takeaway message is that building and maintaining muscle strength is vital to all for overall health and this extends to surviving cancer.  It is not getting old that is the problem, it is getting weaker!

Researchers studied patients with advanced melanoma to understand the illness as it related to muscle strength. They looked at CT scans of the psoas muscle in order to measure core muscle density. The authors then correlated the core muscle density with the risk of metastasis, or spreading of the cancer. 

Patients with higher muscle density were found to have significantly better survival rates and less metastasis.  The authors concluded that decreased muscle density was an important predictor in the outcome of the disease. Furthermore, they stated that “frailty, not age, was associated with decreased disease-free survival.”

Here is theabstract

Sarcopenia as a Prognostic Factor among Patients with Stage III Melanoma.

Abstract

BACKGROUND: Several hypotheses proposed to explain the worse prognosis for older melanoma patients include different tumor biology and diminished host response. If the latter were true, then biologic frailty, and not age, should be an independent prognostic factor in melanoma.

METHODS: Our prospective institutional review board (IRB)-approved database was queried for stage III patients with computed tomography (CT) scans at time of lymph node dissection (LND). Psoas area (PA) and density (PD) were determined in semi-automated fashion. Kaplan-Meier (K-M) survival estimates and Cox proportional-hazard models were used to determine PA and PD impact on survival and surgical complications.

RESULTS: Among 101 stage III patients, PD was significantly associated with both disease-free survival (DFS) (P = 0.04) and distant disease-free survival (DDFS) (P = 0.0002). Cox multivariate modeling incorporating thickness, age, ulceration, and N stage showed highly significant association with PD and both DFS and DDFS. DDFS was significantly associated with Breslow thickness (P = 0.04), number of positive nodes (P = 0.001), ulceration (P = 0.04), and decreasing muscle density (P = 0.01), with hazard ratio of 0.55 [95% confidence interval (CI) 0.35-0.87]. PD also correlated with surgical complications, with odds ratio (OR) of 1.081 [95% CI 1.016-1.150, P = 0.01]. 

CONCLUSIONS: Decreased psoas muscle density on CT, an objective measure of frailty, was as important a predictor of outcome as tumor factors in a cohort of stage III melanoma patients. On multivariate analysis, frailty, not age, was associated with decreased disease-free survival and distant disease-free survival, and higher rate of surgical complications.