Aspirin May Help Treat Colon Cancer
Study Shows Aspirin Use Boosts Survival Rate of People With Colon Cancer
Aspirin-Resistant Colon Cancer continued...
That might raise an eyebrow or two, particularly since aspirin use has been linked to reduced risk of colorectal cancer.
The researchers say the finding suggests that some colorectal cancer tumors may be resistant to aspirin's effects, while others may be especially susceptible. Aspirin is believed to block a substance called cyclooxygenase-2 (Cox-2). Cox-2 promotes inflammation and cell growth. If the substance is overexpressed, the tumor is called Cox-2-positive; tumors that do not overexpress the substance are called Cox-2-negative tumors.
Cox-2-positive colorectal tumors may be especially sensitive to aspirin's anticancer effects. In the study, the survival improvements were seen primarily among those with such tumors. Specifically, patients with Cox-2-positive colorectal tumors who used aspirin regularly after diagnosis had a 61% lower risk of colorectal cancer death and 38% lower overall death risk than non-aspirin users.
Survival in those with the Cox-2-negative tumors did not appear to be affected by aspirin use.
The new findings could one day lead to aspirin-based therapies for patients with newly diagnosed, early-stage colorectal cancer. However, the researchers do not recommend the routine use of aspirin or related medicines for cancer treatment until further studies are done. Aspirin and other Cox-2 inhibitors can cause potentially dangerous side effects such as gastrointestinal bleeding.
In an accompanying editorial published in the same journal, Alfred I. Neugut, MD, PhD, of Columbia University, adds that aspirin-related survival studies should also be done in patients with metastatic colorectal cancer.