title: Endometrial cancer risk factors by 2 main histologic subtypes: the NIH-AARP Diet and Health Study.
abstract: On the basis of clinical and pathologic criteria, endometrial carcinoma has been distinguished as types I (mainly endometrioid) and II (nonendometrioid). Limited data suggest that these subtypes have different risk factor profiles. The authors prospectively evaluated risk factors for types I (n = 1,312) and II (n = 138) incident endometrial carcinoma among 114,409 women in the National Institutes of Health (NIH)-AARP Diet and Health Study (1995-2006). For individual risk factors, relative risks were estimated with Cox regression by subtype, and P(heterogeneity) was assessed in case-case comparisons with type I as the referent. Stronger relations for type I versus Type II tumors were seen for menopausal hormone therapy use (relative risk (RR) of 1.18 vs. 0.84; P(heterogeneity) = 0.01) and body mass index of ≥30 vs. <30 kg/m2 (RR of 2.93 vs. 1.83; P(heterogeneity) = 0.001). Stronger relations for type II versus type I tumors were observed for being black versus white (RR of 2.18 vs. 0.66; P(heterogeneity) = 0.0004) and having a family history of breast cancer (RR of 1.93 vs. 0.80; P(heterogeneity) = 0.002). Other risk factor associations were similar by subtype. In conclusion, the authors noted different risk factor associations for Types I and II endometrial carcinomas, supporting the etiologic heterogeneity of these tumors. Because of the limited number of Type II cancers, additional evaluation of risk factors will benefit from consortial efforts.
authors.affiliation: Hormonal and Reproductive Epidemiology Branch, National Cancer Institute, NIH, Department of Human Services, Bethesda, USA. yanghan@mail.nih.gov
authors.forename: Hannah P
authors.initials: HP
authors.lastname: Yang
authors.forename: Nicolas
authors.initials: N
authors.lastname: Wentzensen
authors.forename: Britton
authors.initials: B
authors.lastname: Trabert
authors.forename: Gretchen L
authors.initials: GL
authors.lastname: Gierach
authors.forename: Ashley S
authors.initials: AS
authors.lastname: Felix
authors.forename: Marc J
authors.initials: MJ
authors.lastname: Gunter
authors.forename: Albert
authors.initials: A
authors.lastname: Hollenbeck
authors.forename: Yikyung
authors.initials: Y
authors.lastname: Park
authors.forename: Mark E
authors.initials: ME
authors.lastname: Sherman
authors.forename: Louise A
authors.initials: LA
authors.lastname: Brinton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D018269:Carcinoma, Endometrioid / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D016889:Endometrial Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D057566:Self Report; D014481:United States / Q000453:epidemiology