title: Chronic tamoxifen use is associated with a decreased risk of intestinal metaplasia in human gastric epithelium.
abstract: BACKGROUND
  Intestinal metaplasia (IM), a premalignant lesion, is associated with an increased risk of gastric cancer. Although estrogen exposure, including tamoxifen, has been studied in correlation with gastric cancer, little has been investigated about its effects on IM.
  
  
  OBJECTIVE
  Therefore, we investigated whether chronic tamoxifen use was associated with the risk of IM in human stomach.
  
  
  METHODS
  We evaluated 512 gastric biopsies from 433 female breast cancer patients that underwent endoscopic gastroduodenoscopy (EGD) ≥6 months after breast surgery. Histopathological findings were scored according to the updated Sydney classification. Demographic and clinical characteristics were also included to identify predictive factors for IM.
  
  
  RESULTS
  In a multivariate logistic regression analysis, age at EGD (odds ratio [OR], 1.04; P = 0.002), biopsies from antrum (OR 2.08; P < 0.001), and Helicobacter pylori positivity (OR 1.68; P = 0.016) were significantly associated with an increased risk of IM, whereas chronic tamoxifen use (≥3 months) was associated with a decreased risk of IM (OR 0.59; P = 0.025). After stratifying by biopsy site, association between tamoxifen use and IM persisted for corpus (OR 0.42; P = 0.026) but not for antrum (OR 0.74; P = 0.327). In analysis limited to patients with follow-up EGD, chronic tamoxifen use also correlated with improved IM score compared to no tamoxifen use (improved, 77.8 vs. 22.2%; no change, 65.4 vs. 34.6%; worsened, 30.0 vs. 70.0%; P = 0.019).
  
  
  CONCLUSIONS
  This study suggests that chronic tamoxifen use can decrease the risk of IM in human stomach. The effect of tamoxifen is predominantly observed in the corpus.
authors.affiliation: Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108, Pyung-Dong, Jongro-gu, Seoul, 110-746, Republic of Korea, docmcm75@gmail.com.
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Moon
authors.forename: Seok-Hyung
authors.initials: SH
authors.lastname: Kim
authors.forename: Sang Kil
authors.initials: SK
authors.lastname: Lee
authors.forename: Jiyeon
authors.initials: J
authors.lastname: Hyeon
authors.forename: Ja Seung
authors.initials: JS
authors.lastname: Koo
authors.forename: Sangheun
authors.initials: S
authors.lastname: Lee
authors.forename: Jean S
authors.initials: JS
authors.lastname: Wang
authors.forename: Won Jae
authors.initials: WJ
authors.lastname: Huh
authors.forename: Shradha S
authors.initials: SS
authors.lastname: Khurana
authors.forename: Jason C
authors.initials: JC
authors.lastname: Mills
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000188:drug therapy; D004334:Drug Administration Schedule; D004848:Epithelium / Q000187:drug effects* / Q000473:pathology; D005260:Female; D006801:Humans; D008679:Metaplasia / Q000517:prevention & control*; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012044:Regression Analysis; D012307:Risk Factors; D013270:Stomach / Q000187:drug effects* / Q000473:pathology; D013629:Tamoxifen / Q000008:administration & dosage* / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D013629:Tamoxifen