Study: Arthritis Pain Killer May Also Help Fight Cancer

A pain reliever commonly used to treat serious and painful forms of arthritis may also reduce the growth of malignant tumors after cancer surgery, according to researchers at Johns Hopkins University School of Nursing and Tel Aviv University.

Indomethacin (Indocin), a nonsteroidal anti-inflammatory medication, given to rats after surgery reduced the growth of tumors by more than 50 percent, the researchers reported in the Journal of Pain.

"These findings provide further support to our supposition that unmanaged pain is associated with potentially life-threatening consequences," said Gayle Page, associate professor and co-author of the study. "If our results in animals prove to be similar in humans, controlling postoperative pain and inflammation must become a priority in the management of cancer patients undergoing surgery."

Prior research in laboratory animals has shown that pain and surgical trauma suppress the immune system's natural killer cells, trigger an inflammatory response and significantly increase the growth of tumors.

"We have already tested other pain relievers, such as morphine and fentanyl, and shown that they provide some protection against tumor-promoting effects of surgery, but these drugs are pain relievers without anti-inflammatory action," said Page. "So we chose to test indomethacin because it eases both pain and inflammation and is injectable, giving us control in its administration."

A total of 124 rats without a tendency to grow tumors were anesthetized, subjected to surgery, given indomethacin, and injected with cancer cells. After surgery, female rats had an overall 200 percent increase in lung tumor growth, and tumor growth in the male rats increased by 350 percent. Two doses of indomethacin reduced tumor development in both the female and male rats by up to 63 percent.

Researchers found that rats undergoing surgery showed suppressed natural killer cell activity, which was restored after receiving indomethacin.

Both the male and female rats given indomethacin exhibited behavior suggesting that their abdominal discomfort was relieved.

Indomethacin is used in the treatment of moderate to severe rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, and acute gouty arthritis.

Other sources: Johns Hopkins