A study presented at the 2016 Genitourinary Cancers Symposium last week warns that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen but not aspirin or acetaminophen (Tylenol), appear to be associated with fatal cases of renal cell carcinoma (RCC).
The data from the study suggest that non-aspirin NSAID use is associated with an increase in the incidence of fatal RCC after at least 4 years of use. They suggest that the NSAIDs cause some kind of impact to the kidney itself. However, they conclude that the relationship between non-aspirin NSAIDs and RCC is not causal, but there is a clear association. More work is needed to to determine what is happening.