Nonsteroidal anti-inflammatory drugs (NSAIDs) appear to have a protective effect against several cancers, but the few human studies examining the relationship between these medications and squamous cell carcinoma (SCC) – the second most common form of skin cancer – have yielded conflicting results.

New findings from a retrospective case-control study, however, show that regular use of NSAIDs resulted in no statistically significant reduction in SCC risk. Investigators evaluated use of any NSAID, aspirin, ibuprofen, and nonaspirin NSAIDs in 415 people with SCC and 415 without. Acetaminophen was used as a comparison drug because it is often used for the same indications as an NSAID, but acetaminophen is not thought to protect against skin cancer.

 “We did not detect any consistent relationships between SCC risk and overall NSAID, aspirin, ibuprofen, or nonaspirin NSAID use,” the researchers wrote in a report, published online by Archives of Dermatology.

More specific findings included the following:

  • People who used NSAIDs for only a short period of time (one to three years) appeared to be at somewhat increased risk for SCC, but the investigators found no consistent effects of duration of use of any NSAID on SCC risk.
  • Neither regular aspirin use nor duration of aspirin use was associated with SCC risk, and SCC risk was the same for high-dose and low-dose aspirin users.
  • Ibuprofen appeared to protect against SCC, with regular users showing a nonsignificant, slightly lower risk than never/occasional users.
  • Use of nonaspirin NSAIDs did not significantly reduce SCC risk.
  • As expected, regular acetaminophen use, acetaminophen dose, and acetaminophen duration had no bearing on SCC risk.