Long-term, regular use of acetaminophen (Tylenol®) may increase the risk of leukemia and lymphoma. These results were published in the Journal of Clinical Oncology.
Some studies have suggested that use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may reduce the risk of colorectal cancer and certain other types of cancer. Acetaminophen—another commonly used type of pain reliever—has a different mechanism of action than NSAIDs, and may have a different effect on cancer risk.
Hematologic cancers refer to cancers of the blood or bone marrow, such as leukemia and lymphoma. To explore the relationship between NSAIDs and acetaminophen and risk of hematologic cancers, researchers evaluated information from the Vitamins and Lifestyle (VITAL) study.
The study enrolled more than 64,000 men and women between the ages of 50 and 76. None of the participants had a history of cancer (other than non-melanoma skin cancer) at the start of the study.
During roughly 6 ½ years of follow-up, 577 study participants (0.9%) developed a hematologic cancer.
For each type of drug (acetaminophen, aspirin, and non-aspirin NSAIDs), high use was defined as use at least four times a week for at least four years.
- Compared with people who did not use acetaminophen, high users of acetaminophen had an almost two-fold increased risk of a hematologic cancer. This increased risk was seen for myeloid disorders (such as myelodysplastic syndrome and acute myeloid leukemia), non-Hodgkin’s lymphoma, and plasma cell disorders, but not for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL).
- Overall, use of aspirin or non-aspirin NSAIDs did not affect the risk of hematologic cancers.
These results suggest that regular, long-term use of acetaminophen may increase the risk of leukemia and lymphoma. The researchers note, however, that “supporting evidence from other prospective studies would be needed before any recommendations about acetaminophen use could be made.”
Reference: Walter RB, Milano F, Brasky TM, White E. Long-term use of acetaminophen, aspirin, and other nonsteroidal anti-inflammatory drugs and risk of hematologic malignancies: results from the prospective Vitamins and Lifestyle (VITAL) Study. Journal of Clinical Oncology. Early online publication May 9, 2011.