Use of nonsteroidal anti-inflammatory drugs and risk of endometrial cancer: a nationwide case-control study

Aspirin use and endometrial cancer risk: a meta-analysis and systematic review

Background

The use of aspirin has been linked to a reduced risk of cancer at several sites, such as the breast, prostate, and colorectum. However, the evidence for this chemopreventive effect from aspirin use on endometrial cancer is conflicting, and whether an association exists is an open question.

Methods

After carrying out a database search of articles published up to December 2019, we identified 7 case-control studies and 11 cohort studies, including a total of 14,766 endometrial cancer cases. We pooled the odds ratios (ORs) in case-control studies and risk ratios (RRs) in cohort studies, and then conducted subgroup analysis based on factors such as the frequency and duration of aspirin use, and obesity.

Results

In the overall meta-analysis, we found a significant inverse association between any aspirin use and the risk of endometrial cancer both in case-control studied [pooled ORs =0.88, 95% confidence interval (CI): 0.78–0.98] and cohort studies (pooled RRs =0.86, 95% CI: 0.86–0.99). In the subgroup analysis, a negative association was observed between the maximal frequency of aspirin use and the endometrial cancer risk (pooled ORs/RRs: 0.82; 95% CI: 0.71–0.95), but no correlations were observed based on the longest duration of aspirin use or obesity.

Conclusions

Our results suggest that the use of aspirin was associated with a reduced risk of endometrial cancer, and the reduced risk was closely related to the high-frequency of use. Further randomized controlled trials (RCTs) are needed to confirm these findings.

Associations between aspirin use and the risk of cancers: a meta-analysis of observational studies

Background

Epidemiological studies have clarified the potential associations between regular aspirin use and cancers. However, it remains controversial on whether aspirin use decreases the risk of cancers risks. Therefore, we conducted an updated meta-analysis to assess the associations between aspirin use and cancers.

Methods

The PubMed, Embase, and Web of Science databases were systematically searched up to March 2017 to identify relevant studies. Relative risks (RRs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

A total of 218 studies with 309 reports were eligible for this meta-analysis. Aspirin use was associated with a significant decrease in the risk of overall cancer (RR = 0.89, 95% CI: 0.87–0.91), and gastric (RR = 0.75, 95% CI: 0.65–0.86), esophageal (RR = 0.75, 95% CI: 0.62–0.89), colorectal (RR = 0.79, 95% CI: 0.74–0.85), pancreatic (RR = 0.80, 95% CI: 0.68–0.93), ovarian (RR = 0.89, 95% CI: 0.83–0.95), endometrial (RR = 0.92, 95% CI: 0.85–0.99), breast (RR = 0.92, 95% CI: 0.88–0.96), and prostate (RR = 0.94, 95% CI: 0.90–0.99) cancers, as well as small intestine neuroendocrine tumors (RR = 0.17, 95% CI: 0.05–0.58).

Conclusions

These findings suggest that aspirin use is associated with a reduced risk of gastric, esophageal, colorectal, pancreatic, ovarian, endometrial, breast, and prostate cancers, and small intestine neuroendocrine tumors.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4156-5) contains supplementary material, which is available to authorized users.

Aspirin use and endometrial cancer risk and survival

The role of acetylsalicylic acid (aspirin) as a chemo-preventive and adjuvant therapeutic agent for cancers is generating attention. Mounting evidence indicates that aspirin reduces the incidence and mortality of certain obesity-related cancers, particularly colorectal cancer. In endometrial cancer, previous studies examining the effect of aspirin remain inconsistent as to the reduction in the risk of endometrial cancer. While some evidence indicates protective effects in obese women, other studies have showed a potential deleterious effect of these medications on endometrial cancer outcomes. However, exposure measurement across studies has been inconsistent in recording dose, duration, and frequency of use; thus making comparisons difficult. In this article, we review the evidence for the association between endometrial cancer and obesity, the pharmacological differences between regular- and low-dose aspirin, as well as the potential anti-tumor mechanism of aspirin, supporting a possible therapeutic effect on endometrial cancer. A proposed mechanism behind decreased cancer mortality in endometrial cancer may be a result of inhibition of metastasis via platelet inactivation and possible prostaglandin E₂ suppression by aspirin. Additionally, aspirin use in particular may have a secondary benefit for obesity-related comorbidities including cardiovascular disease in women with endometrial cancer. Although aspirin-related bleeding needs to be considered as a possible adverse effect, the benefits of aspirin therapy may exceed the potential risk in women with endometrial cancer. The current evidence reviewed herein has resulted in conflicting findings regarding the potential effect on endometrial cancer outcomes, thus indicating that future studies in this area are needed to resolve the effects of aspirin on endometrial cancer survival, particularly to identify specific populations that might benefit from aspirin use.

Can Aspirin Reduce the Risk of Endometrial Cancer?: A Systematic Review and Meta-analysis of Observational Studies

Current evidences suggest that nonsteroidal anti-inflammatory drugs can reduce the risk of several types of cancer, including breast, prostate, and colorectal cancer. However, evidences regarding the chemopreventive effect of aspirin to endometrial cancer are inconsistent. Therefore, we aimed to further explore the association. We searched PubMed, EMBASE, Web of Science, and Scopus to identify potentially eligible studies. After title/abstract screening and full-text review, we identified 7 cohort studies and 6 case-control studies. Data extraction and quality assessment were performed independently, and a random-effects model was used for data synthesis. Subgroup analysis was conducted based on obesity, hormone replacement therapy use, and cancer subtype; sensitivity analysis was conducted by pooling risk ratios of the highest dosage or longest duration of use. Dose-response relationship was assessed by a 2-stage linear dose-response model. Statistical heterogeneity was assessed by the I value and a χ test for the Cochrane Q statistic. In overall meta-analysis, the pooled risk ratio was 0.93 (95% confidence interval, 0.88-0.99), and no substantial statistical heterogeneity was observed (I = 0.0%, P = 0.550). In subgroup analysis, a negative association was observed for obese women and type I endometrial cancer. Higher dosage or frequency of aspirin use was significantly associated with a reduced risk, and long-term aspirin use was protective only for obese women. In conclusion, our study suggests that the use of aspirin can reduce the risk of endometrial cancer, particularly for obese women. However, the generalizability of our conclusion should be further studied for premenopausal women and type II endometrial cancer.

Time trends in the incidence of hysterectomy-corrected overall, type 1 and type 2 endometrial cancer in Denmark 1978-2014

OBJECTIVE

To investigate time trends in the incidence of overall, type 1 and type 2 endometrial cancer in Denmark 1978-2014, correcting for hysterectomy.

METHODS

Based on the Danish Cancer Registry and the Danish National Patient Registry we calculated hysterectomy-corrected incidence rates of overall, type 1 and type 2 endometrial cancer. Separate analyses for women <55years (defined as pre- and perimenopausal age) and women aged ≥55years (defined as postmenopausal age) and analyses allowing for different time trends before and after the study period midyear 1996 were performed. Log-linear Poisson models were used to estimate annual percentage change (APC) in incidence with 95% confidence intervals (CI).

RESULTS

The overall incidence of endometrial cancer decreased slightly from 1978 to 1995, but in the last two decades of the study period the incidence has been stable (APC=0.16; 95% CI: -0.19; 0.50). In the study period (1978-2014) type 1 endometrial cancer incidence decreased slightly (APC=-0.67; 95% CI:-0.83; -0.52), whereas the incidence of type 2 endometrial cancer increased substantially (APC=4.85; 95% CI: 4.47; 5.23). The decrease in type 1 endometrial cancer was most pronounced before 1996 in women younger than 55 years (APC=-2.79; 95% CI: -3.65; -1.91), while the largest increase in type 2 endometrial cancer was observed after 1996 (APC=6.42; 95% CI: 5.72; 7.12).

CONCLUSIONS

Over a period of more than 35 years, the incidence of type 1 endometrial cancer decreased, mainly in pre- and perimenopausal women, while type 2 endometrial cancer incidence increased.

Risk Factors for Endometrial Cancer: Results from a Hospital-Based Case-Control Study

Objectives: The purpose of this investigation was to examine the association between endometrial cancer and possible etiological agents. Methods: A case-control study was conducted in Iran between March 2012 and May 2016. The demographic and reproductive factors of 205 women with endometrial cancer were compared, and 590 healthy cases were participated in the control group. For each endometrial cancer case, there were three controls, who were matched in terms of age and residence. The data were considered significant at p ≤0.05. Results: After adjusting the variables, the nulliparity (OR 6.23, 95% CI 2.86-13.59), the nulligravidity (OR 5.94, 95% CI 2.51-14.06), the positive family history of reproductive cancer (OR 4.97, 95% CI 2.33-10.59), the infertility history (OR 2.38, 95%CI 1.32-4.31), the obesity (BMI ≥25) (OR 1.71, 95% CI 1.16-2.52), the early menarche age (<12 years) (OR 2.10, 95% CI 1.17-3.75), and the hormonal contraception use (OR 1.69, 95% CI 1.15-2.49) were found to be associated with an increased risk of endometrial cancer. Nevertheless, the education level, the job of women, the marital age, the leisure activities, and the breast feeding were not found to be associated with the endometrial cancer after adjusting the variables. Conclusion: Scheduling of the screening program is vitally indispensable to identify endometrial cancer in women with nulliparity, nulligravidity and the positive family history of cancer. In addition, women with early menarche, those with the history of infertility, the obese ones, and those who use contraception pills need to be particularly aware of the potential risks.

Parity and endometrial cancer risk: a meta-analysis of epidemiological studies

The association between parity and endometrial cancer risk is inconsistent from observational studies. We aimed to quantitatively assess the relationship by summarizing all relevant epidemiological studies. PubMed (MEDLINE), Embase and Scopus were searched up to February 2015 for eligible case–control studies and prospective studies. Random-effects model was used to pool risk estimations. Ten prospective studies, 35 case-control studies and 1 pooled analysis of 10 cohort and 14 case-control studies including 69681 patients were identified. Pooled analysis revealed that there was a significant inverse association between parity and risk of endometrial cancer (relative risk (RR) for parous versus nulliparous: 0.69, 95% confidence interval (CI) 0.65–0.74; I² = 76.9%). By evaluating the number of parity, we identified that parity number of 1, 2 or 3 versus nulliparous demonstrated significant negative association (RR = 0.73, 95% CI 0.64–0.84, I² = 88.3%; RR = 0.62, 95% CI 0.53–0.74, I² = 92.1%; and RR = 0.68, 95% CI 0.65–0.70, I² = 20.0% respectively). The dose-response analysis suggested a nonlinear relationship between the number of parity and endometrial cancer risk. The RR decreased when the number of parity increased. This meta-analysis suggests that parity may be associated with a decreased risk of endometrial cancer. Further studies are warranted to replicate our findings.