Gynecological and reproductive factors and the risk of pancreatic cancer: A case-control study.

Background: /Objectives: Pancreatic ductal adenocarcinoma (PDAC) has a higher incidence in men compared to women, although the difference in known risk factors cannot explain this disparity completely. Reproductive and hormonal factors have been demonstrated in pre-clinical studies to influence pancreatic carcinogenesis, but the few published data on the topic are inconsistent. The aim was to investigate the role of reproductive and hormonal factors on PDAC occurrence in women.

Methods: We conducted a unicenter case-control study; PDAC cases were matched to controls by age with a 1:2 ratio. Risk factors were screened through questionnaires about gynecologic and medical history. Comparisons were made using Chi-square and Fisher's exact tests where appropriate for categorical variables and Student's t-test for continuous variables. Logistic regression was used to calculate Odds Ratios (ORs) and their 95% confidence intervals (CI). Multivariable logistic regression models were adjusted for potential confounders.

Results: 253 PDAC and 506 matched controls were enrolled. At logistic regression multivariable analysis adjusted for confounding factors, older age at menopause (OR:0.95 per year; 95% CI:0.91-0.98; p = 0.007), use of Oral Contraceptives (OR:0.52; 95% CI:0.30-0.89; p = 0.018), use of Hormonal Replacement Therapy (OR:0.31; 95% CI:0.15-0.64; p = 0.001), and having had two children (OR:0.57; 95% CI:0.38-0.84; p = 0.005) were significant, independent protective factors for the onset of PDAC.

Conclusions: These data confirm some previous findings on menopause age and number of births while, to our knowledge, this is the first study to show a protective effect of HRT and OC use. The results collectively support the hypothesis that exposure to estrogens plays a protective role towards PDAC.