Nonsteroidal Anti-inflammatory Drugs and Cyclooxygenase-2 Inhibitors for Primary Prevention of Colorectal Cancer: A Systematic Review Prepared for the U.S. Preventive Services Task Force
Bibliographic record
Abstract
PURPOSE: To examine the benefits and harms of nonaspirin (non-ASA) nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase (COX-2) inhibitors for the prevention of colorectal cancer (CRC) and adenoma. DATA SOURCES: MEDLINE (1966 to 2006), EMBASE (1980 to 2006), Cochrane Central Register of Controlled Trials, Cochrane Collaboration's registry of clinical trials, Cochrane Database of Systematic Reviews. STUDY SELECTION: Randomized, controlled trials and case-control and cohort studies of the effectiveness of NSAIDs for the prevention of CRC and colorectal adenoma were identified by multilevel screening by 2 independent reviewers. Systematic reviews of harms were sought. DATA EXTRACTION: Data abstraction, checking, and quality assessment were completed in duplicate. DATA SYNTHESIS: A single cohort study showed no effect of non-ASA NSAIDs on death due to CRC. Colorectal cancer incidence was reduced with non-ASA NSAIDs in cohort studies (relative risk, 0.61 [95% CI, 0.48 to 0.77]) and case-control studies (relative risk, 0.70 [CI, 0.63 to 0.78]). Colorectal adenoma incidence was also reduced with non-ASA NSAID use in cohort studies (relative risk, 0.64 [CI, 0.48 to 0.85]) and case-control studies (relative risk, 0.54 [CI, 0.4 to 0.74]) and by COX-2 inhibitors in randomized, controlled trials (relative risk, 0.72 [CI, 0.68 to 0.77]). The ulcer complication rate associated with non-ASA NSAIDs is 1.5% per year. Compared with non-ASA NSAIDs, COX-2 inhibitors reduce this risk but, in multiyear use, have a higher ulcer complication rate than placebo. Cyclooxygenase-2 inhibitors and nonnaproxen NSAIDs increase the risk for serious cardiovascular events (relative risk, 1.86 [CI, 1.33 to 2.59] for COX-2 inhibitors vs. placebo). LIMITATIONS: Heterogeneity in the dose, duration and frequency of use necessitated careful grouping for analysis. CONCLUSIONS: Cyclooxygenase-2 inhibitors and NSAIDs reduce the incidence of colonic adenomas. Nonsteroidal anti-inflammatory drugs also reduce the incidence of CRC. However, these agents are associated with important cardiovascular events and gastrointestinal harms. The balance of benefits to risk does not favor chemoprevention in average-risk individuals.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.014 | 0.046 |
| Meta-epidemiology (narrow) | 0.002 | 0.002 |
| Meta-epidemiology (broad) | 0.012 | 0.008 |
| Bibliometrics | 0.014 | 0.014 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.003 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".