Table 3. Summary of relative risks of developing cancer in regular aspirin users (at least 1-2 tablets per week) compared to non-users in several common solid tumours. Data from Bosetti et al. 2012 [24]—a meta-analysis of observational studies assessing aspirin use and cancer incidence. Data on pancreatic, endometrial, ovarian, bladder, and renal cancer are also available, but for these tumour types, the overall results did not reach statistical significance.
| Cancer Type/Study | No of Studies | No of Cases | RR (95% CI) |
|---|---|---|---|
| Colorectal | |||
| Case-control | 15 | 21,414 | 0.63 (0.56-0.70) |
| Cohort | 15 | 16,105 | 0.82 (0.75-0.89) |
| Overall | 30 | 37,519 | 0.73 (0.67-0.79) |
| Gastric Cancer | |||
| Case-control | 7 | 2411 | 0.60 (0.44-0.82) |
| Cohort | 6 | 2108 | 0.77 (0.58-1.04) |
| Overall | 13 | 4519 | 0.67 (0.54-0.83) |
| Oesophageal/cardia adenocarcinoma | |||
| Case-control | 9 | 3222 | 0.60 (0.48-0.75) |
| Cohort | 2 | 499 | 0.88 (0.68-1.15) |
| Overall | 11 | 3721 | 0.64 (0.52-0.78) |
| Oesophageal Squamous Cell Carcinoma/unknown | |||
| Case-control | 7 | 1075 | 0.54 (0.44-0.67) |
| Cohort | 4 | 1118 | 0.73 (0.51-1.07) |
| Overall | 11 | 2193 | 0.61 (0.50-0.76) |
| Breast | |||
| Case-control | 10 | 28.835 | 0.83 (0.76-0.91) |
| Cohort | 22 | 27,091 | 0.93 (0.87-1.00) |
| Overall | 32 | 52.926 | 0.90 (0.85-0.95) |
| Prostate | |||
| Case-control | 9 | 5795 | 0.87 (0.74-1.02) |
| Cohort | 15 | 31,657 | 0.91 (0.85-0.97) |
| Overall | 24 | 37,452 | 0.90 (0.85-0.96) |
| Lung | |||
| Case-control | 5 | 4863 | 0.73 (0.55-0.98) |
| Cohort | 15 | 11,356 | 0.98 (0.92-1.05) |
| Overall | 20 | 16,219 | 0.91 (0.84-0.99) |