Hormone Replacement Therapy in Relation to Breast Cancer

摘要: ContextStudies of long-term hormone replacement therapy (HRT) suggest an associated increased risk breast cancer, but whether this association differs according to histologic type cancer has not been extensively studied.ObjectiveTo determine the between HRT and breast cancer varies by formulation across types.Design, Setting, ParticipantsNested case-control study among 705 postmenopausal women enrolled in the Group Health Cooperative Puget Sound (GHC) who were aged 50 to 74 years and had primary invasive diagnosed July 1, 1990, and December 31, 1995 (cases), 692 randomly selected aged-matched female members of GHC (controls).Main Outcome MeasureIncidence duration use in 5-year period ending 1 year before diagnosis, which was ascertained from computerized pharmacy records.ResultsThe incidence all types combined, increased by 60% 85% recent users HRT, estrogen alone or estrogen plus progestin. Longer (odds ratio [OR], 3.07 for 57 months or more; 95% confidence interval [CI], 1.55-6.06) current combination therapy (OR, 3.91; CI, 2.05-7.44) associated with increased risk of lobular cancer. Long-term a 50% increase in nonlobular 1.52 months or 1.01-2.29).ConclusionOur data add growing body evidence that use of is such use may be related particularly tumors.