HOUSTON -- Many cancer patients who have heart attacks often are not treated with life saving aspirin given the belief in the medical community that they could experience lethal bleeding. Researchers at The University of Texas M. D. Anderson Cancer Center, however, say that notion is now proven wrong and that without aspirin, the majority of these patients will die.
Researchers say that their study, to be published in the February 1, 2007 issue of the journal Cancer and now available online, turns common medical assumptions upside down and will likely change medical practice for cancer patients. Because aspirin can thin blood and cancer patients experience low platelet counts and abnormal clotting, physicians view aspirin as a relative contraindication. Given that blood platelets are responsible for the clotting process, physicians do not eagerly prescribe aspirin as a standard treatment.
In this study, however, the investigators found that 9 of 10 cancer patients with thrombocytopenia (low platelet count) who were experiencing a heart attack and who did not receive aspirin died, whereas only one patient died in a group of 17 similar cancer patients who received aspirin. They also found aspirin helps cancer patients with normal platelet count survive heart attacks, just as it does for people without cancer.
"The notion that heart attacks in patients with low platelets should be treated with clot-dissolving aspirin defies logic, that is unless you suspect that the cancer is interfering with platelet function," says the study's senior investigator and author, Jean-Bernard Durand, M.D., assistant professor in the Department of Cardiology at M. D. Anderson Cancer Center.
"We believe tumors may be releasing chemicals that allow the cancer to form new blood supplies which makes blood more susceptible to forming clots." Durand, a heart failure specialist, says. "There appears to be a platelet paradox suggesting that cancer may
Contact: Laura Sussman
University of Texas M. D. Anderson Cancer Center