Building muscle is important in all stages of cancer

sPhysical weakness plays an important role in patients with advanced cancers. Approximately one-third of cancer deaths are thought to be attributable to a wasting syndrome called cachexia, which is characterized by significant loss of skeletal muscle mass and weight. Clinicians have also identified sarcopenia, or muscle wasting generally associated with aging, as an important prognostic indicator in patients with advanced cancer. In general, the less muscle mass a patient with advanced cancer has, the less likely they are to survive the disease. But new studies show that early-stage cancer patients are also at risk, and doctors hope more research will show that building more muscle can help patients recover. “The goal is to change the prognosis. Additional studies are needed to determine if increasing muscle mass in patients can improve outcomes,”

The most recent study, published in the April issue of JAMA Oncology , followed 3,241 patients with stage II and III breast cancer, concluding that patients with low muscle mass at diagnosis had a lower chance of survival than patients without sarcopenia. In the study, none of the patients’ cancers had spread outside the breast at the time of diagnosis. The study authors concluded that although sarcopenia occurs in more than a third of patients newly diagnosed with non-metastatic breast cancer, the condition has not been recognized in this population.

The authors also said that the findings may apply to many other non-metastatic cancers, where the association between higher muscle mass and improved survival in patients with metastatic disease has been observed in patients with a variety of solid tumors. A similar trial led by the study’s lead investigator, for example, linked decreased muscle mass in patients with non-metastatic colorectal cancer to a poorer prognosis.

Leukopenia, combined with high body fat, worsens the outlook for patients. In the JAMA study, breast cancer patients with sarcopenia and a lot of body fat were 89 percent more likely to die from the disease. The American Society of Clinical Oncology also found that sarcopenia combined with inflammation nearly doubled the risk of death from cancer for patients.

Based on the findings, the researchers advise clinicians to recommend strength training for patients with non-invasive disease, as well as weight loss and diet changes. “I recommend exercise, as well as a healthy diet, as there are studies showing the benefits of a healthy lifestyle in reducing the risk of breast cancer recurrence,” says Dr. Lynch. “I look forward to seeing the studies conducted that will evaluate the effects of improving muscle mass on breast cancer outcomes.”