Regular Low-Dose Aspirin Linked to Smaller Lung and Colon Cancer Tumors
Effect of aspirin not so pronounced in prostate and breast cancers (August 16)
In a study published in the British Journal of Cancer, patients with colon and lung cancer who regularly took low-dose aspirin before their diagnosis tended to have less advanced tumors.
Scientists have long known that daily use of aspirin is associated with reduced cancer mortality. To explore this association, researchers in Sweden compared tumor characteristics among aspirin users and non-users.
The investigators identified patients diagnosed with colorectal, lung, prostate, and breast cancers between 2006 and 2009 in the Swedish Cancer Register and matched them to the Swedish Prescribed Drug Register to obtain information on low-dose aspirin use prior to diagnosis. Data were obtained for 17,041 colorectal, 9,766 lung, 29,770 prostate, and 20,299 breast cancer patients.
The proportion of low-dose aspirin users was approximately 26% among colorectal, lung, and prostate cancer patients and approximately 14% among breast cancer patients. When adjusted for age, gender, education level, and place of residence, low-dose aspirin use was associated with lower tumor extent (T) for colorectal and lung cancers (P < 0.0001) but not for prostate and breast cancers. For all cancers, the researchers found no evidence of an association of aspirin use with nodal involvement (N). Except for a borderline result in prostate cancer, aspirin use was associated with a lower rate of metastatic disease.
Among the histological subgroups of lung cancer, significant differences in tumor extent were observed in patients with adenocarcinoma. There was a significant reduction of approximately 20 to 30 percent in the odds of metastasis among aspirin users across subgroups.
The authors concluded that the use of low-dose aspirin in the year prior to diagnosis was associated with lower tumor extent and less metastatic disease for colorectal and lung cancers, but not for prostate and breast cancers.
The findings don’t mean, however, that everyone should take aspirin to ward off advanced cancer, the authors caution. Regular aspirin use has been shown to increase the chance of gastrointestinal bleeds. Ideally, only those at high risk for developing cancer should consider taking low-dose aspirin, they say.