MAR 19, 2019

Efficacy of Cancer Therapeutics is Better When Muscle Mass is Normal

WRITTEN BY: Carmen Leitch

People have been pumping iron to improve their physique for many years, and it’s known that exercise is related to good health. Now scientists have determined that increasing muscle mass could be a life-saver. Researchers at Osaka University found that the loss of skeletal muscles, also known as sarcopenia, is closely related to a lack of responsiveness to therapeutics aimed at advanced non-small cell lung cancer (NSCLC). The findings have been published in Scientific Reports, and are briefly summarized in the video.

Treatments for NSCLC are called programmed cell death (PD-1) inhibitors; they are a relatively new class of drugs that have the potential to combat various types of cancer. They are designed to enhance a patient’s ability to use their own immune system to attack cancer, and as such, depend heavily on the proper function of that patient’s immune system.

Unfortunately, only a small number of patients respond well to these drugs. The Osaka researchers are hopeful that their work will help address this problem. 

“Sarcopenia is a well-known risk factor associated with poor outcomes for several cancer types," said the lead author of the report, Takayuki Shiroyama. "Because muscle degradation is associated with a dysregulated immune response, we wanted to investigate how, in lung cancer patients, sarcopenia impacts the efficacy of PD-1 inhibitor therapy.”

In this study, the scientists assessed the medical records of 42 advanced NSCLC patients who had also been checked for muscle mass to see how well they responded to PD-1 inhibitors. 

“The results were surprisingly emphatic. We found that the treatment outcomes for patients with sarcopenia at the start of therapy were far worse than those without,” revealed the senior author of the work Atsushi Kumanogoh.

The researchers determined that one year after treatment, 38.1 percent of non-sarcopenia patients were in remission but only 10.1 percent of sarcopenia patients had no progression in tumor growth in that same time period.  

“Our findings suggest that baseline skeletal muscle mass has a substantial impact on PD-1 inhibitor efficacy. As such, skeletal muscle mass might be useful for predicting whether treatment is likely to be effective,” explained Shiroyama.

Muscle wasting is commonly observed in patients who have advanced cancer. Some new drugs may help increase skeletal muscle mass, which could be very important to the success of therapeutics.

Patients that will be receiving PD-1 inhibitor therapy may also increase the likelihood that the treatment will be successful if they aim to increase muscle mass before treatment begins.

 

Sources: AAAS/Eurekalert! Via Osaka University, Scientific Reports