NSAIDs may protect against bladder cancer

NEW YORK (Reuters Health) - Regular use of non-steroidal anti-inflammatory drugs (NSAIDs), especially aspirin, may decrease the risk of bladder cancer, particularly more advanced, high-grade tumors containing alterations in the tumor suppressor protein TP53, results of a study suggest.

The findings also provide further evidence of an increased risk of bladder cancer among users of phenacetin-containing analgesics, particularly long-term users. Phenacetin was withdrawn from the U.S. market in the 1980s after it was implicated in kidney damage and cancer.

For their study, Dr. Margaret R. Karagas of Dartmouth Medical School, Hanover, New Hampshire, and colleagues assessed lifetime use of analgesics and NSAIDs with the bladder cancer incidence in a population-based case-control study. Other common NSAIDs include naproxen (Aleve) and ibuprofen (Motrin).

There were 376 cases of bladder cancer and 463 healthy subjects (controls) from New Hampshire. Overall, 42 percent of the cancer patients and 45 percent of the controls reported regular use of a pain reliever.

Patients with bladder cancer reported regular phenacetin use more than twice as often than the controls did, the researchers report in the current online issue of the peer-reviewed journal BMC Urology. Regular phenacetin users of more than 8 years had a three-fold increased risk of bladder cancer.

In contrast, there was no correlation, overall, between the use of acetaminophen (also known as paracetamol) and risk of bladder cancer.

However, regular use of any NSAID was associated with a statistically significant reduced risk of bladder cancer, an association that was largely due to regular aspirin use. Regular NSAID use seemed to protect against invasive, high-grade and TP53-positive tumors, in particular.

Karagas and colleagues suggest that, "in light of the chemopreventive effects of NSAIDs including aspirin for other neoplasms, the possibility that they may reduce bladder cancer incidence warrants further consideration. Studies assessing the effect on bladder cancer prognosis are lacking but would be of great interest."

SOURCE: BMC Urology, August 10, 2007.