Patients with non-small-cell lung cancer (NSCLC) taking beta-blockers for heart problems, in addition to their radiation treatments, lived 22% longer than patients not using beta-blockers, according to a large cohort study.

“These findings were the first, to our knowledge, demonstrating a survival benefit associated with the use of beta blockers and radiation therapy for lung cancer,” said lead researcher Daniel Gomez, M.D., an assistant professor in the department of radiation oncology at the University of Texas M.D. Anderson Cancer Center in Houston. “The results imply that there may be another mechanism, largely unexplored, that could potentially reduce the rates of tumor spread in patients with this very aggressive disease.”

In the study, beta-blocker use was associated with improved distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) in NSCLC patients. Beta-blocker made no difference in the length of survival without the disease progressing in the part of the lungs where it started, according to the authors.

The researchers speculate that the benefit may be tied to the beta-blockers’ suppression of norepinephrine, which is known to promote the spread of cancer cells.

“Right now, we would not advocate that patients take beta blockers for this purpose, until these findings can be validated by prospective trials,” said Gomez. “In addition, future studies will help us to understand if the mechanism that we propose is correct, and thus if beta blockers are indeed directly affecting the aggressiveness of this cancer or if these findings are due to the activation or inhibition of another pathway.”