***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: CONTEXT The Women 's Health Initiative trial of combined estrogen plus progestin was stopped early when overall health risks , including invasive breast cancer , exceeded benefits . Outst and ing issues not previously addressed include characteristics of breast cancers observed among women using hormones and whether diagnosis may be influenced by hormone effects on mammography . OBJECTIVE To determine the relationship among estrogen plus progestin use , breast cancer characteristics , and mammography recommendations . DESIGN , SETTING , AND PARTICIPANTS Following a comprehensive breast cancer risk assessment , 16 608 postmenopausal women aged 50 to 79 years with an intact uterus were r and omly assigned to receive combined conjugated equine estrogens ( 0.625 mg/d ) plus medroxyprogesterone acetate ( 2.5 mg/d ) or placebo from 1993 to 1998 at 40 clinical centers . Screening mammography and clinical breast examinations were performed at baseline and yearly thereafter . MAIN OUTCOME MEASURES Breast cancer number and characteristics , and frequency of abnormal mammograms by estrogen plus progestin exposure . RESULTS In intent-to-treat analyses , estrogen plus progestin increased total ( 245 vs 185 cases ; hazard ratio [ HR ] , 1.24 ; weighted P<.001 ) and invasive ( 199 vs 150 cases ; HR , 1.24 ; weighted P = .003 ) breast cancers compared with placebo . The invasive breast cancers diagnosed in the estrogen plus progestin group were similar in histology and grade but were larger ( mean [ SD ] , 1.7 cm [ 1.1 ] vs 1.5 cm [ 0.9 ] , respectively ; P = .04 ) and were at more advanced stage ( regional/metastatic 25.4 % vs 16.0 % , respectively ; P = .04 ) compared with those diagnosed in the placebo group . After 1 year , the percentage of women with abnormal mammograms was substantially greater in the estrogen plus progestin group ( 716 [ 9.4 % ] of 7656 ) compared with placebo group ( 398 [ 5.4 % ] of 7310 ; P<.001 ) , a pattern which continued for the study duration . CONCLUSIONS Relatively short-term combined estrogen plus progestin use increases incident breast cancers , which are diagnosed at a more advanced stage compared with placebo use , and also substantially increases the percentage of women with abnormal mammograms . These results suggest estrogen plus progestin may stimulate breast cancer growth and hinder breast cancer diagnosis In the 1990s , two r and omised clinical trials started in Sc and inavia addressing whether hormone replacement therapy ( HRT ) is safe for women with previous breast cancer . We report the findings of the safety analysis in HABITS ( hormonal replacement therapy after breast cancer -- is it safe ? ) , an open r and omised clinical trial with allocation to either HRT or best treatment without hormones . The main endpoint was any new breast cancer event . All analyses were done according to intention-to-treat . Until September , 2003 , 434 women were r and omised ; 345 had at least one follow-up report . After a median follow-up of 2.1 years , 26 women in the HRT group and seven in the non-HRT group had a new breast-cancer event . All women with an event in the HRT group and two of those in the non-HRT group were exposed to HRT and most women had their event when on treatment . We decided that these findings indicated an unacceptable risk for women exposed to HRT in the HABITS trial , and the trial was terminated on Dec 17 , 2003 PURPOSE To determine whether estrogen replacement therapy ( ERT ) alters the development of new or recurrent breast cancer in women previously treated for localized breast cancer . PATIENTS AND METHODS Potential participants ( n = 319 ) in a trial of ERT after breast cancer were observed prospect ively for at least 2 years whether they enrolled onto the r and omized trial or not . Of 319 women , 39 were given estrogen and 280 were not given hormones .  Tumor size , number of lymph nodes , estrogen receptors , menopausal status at diagnosis , and disease-free interval at the initiation of the observation period were comparable for the trial participants ( n = 62 ) versus non participants ( n = 257 ) and for women on ERT  ( n = 39 ) versus controls ( n = 280 ) . Cancer events were ascertained for both groups . RESULTS Patient and disease characteristics were comparable for the trial participants versus non participants , as well as for the women on ERT versus the controls . One patient in the ERT group developed a new lobular estrogen receptor-positive breast cancer 72 months after the diagnosis of a ductal estrogen receptor-negative breast cancer and 27 months after initiation of ERT . In the control group , there were 20 cancer events : 14 patients developed new or recurrent breast cancer at a median time of 139.5 months after diagnosis and six patients developed other cancers at a median time of 122 months . CONCLUSION ERT does not seem to increase breast cancer events in this subset of patients previously treated for localized breast cancer . Results of r and omized trials are needed before any changes in current st and ards of care can be proposed BACKGROUND Hormone replacement therapy ( HRT ) is typically avoided for women with a history of breast cancer because of concerns that estrogen will stimulate recurrence . In this study , we sought to evaluate the impact of HRT on recurrence and mortality after a diagnosis of breast cancer . METHODS Data were assembled from 2755 women aged 35 - 74 years who were diagnosed with incident invasive breast cancer while they were enrolled in a large health maintenance organization from 1977 through 1994 . Pharmacy data identified 174 users of HRT after diagnosis . Each HRT user was matched to four r and omly selected nonusers of HRT with similar age , disease stage , and year of diagnosis . Women in the analysis were recurrence free at HRT initiation or the equivalent time since diagnosis . Rates of recurrence and death through 1996 were calculated . Adjusted relative risks were estimated by use of the Cox regression model . All statistical tests were two-sided . RESULTS The rate of breast cancer recurrence was 17 per 1000 person-years in women who used HRT after diagnosis and 30 per 1000 person-years in nonusers ( adjusted relative risk for users compared with nonusers = 0.50 ; 95 % confidence interval [ CI ] = 0.30 to 0.85 ) . Breast cancer mortality rates were five per 1000 person-years in HRT users and 15 per 1000 person-years in nonusers ( adjusted relative risk = 0.34 ; 95 % CI = 0.13 to 0.91 ) . Total mortality rates were 16 per 1000 person-years in HRT users and 30 per 1000 person-years in nonusers ( adjusted relative risk = 0.48 ; 95 % CI = 0.29 to 0.78 ) . The relatively low rates of recurrence and death were observed in women who used any type of HRT ( oral only = 41 % of HRT users ; vaginal only = 43 % ; both oral and vaginal = 16 % ) . No trend toward lower relative risks was observed with increased dose . CONCLUSION We observed lower risks of recurrence and mortality in women who used HRT  after breast cancer diagnosis than in women who did not . Although residual confounding may exist , the results suggest that HRT after breast cancer has no adverse impact on recurrence and mortality OBJECTIVE To evaluate the feasibility of conducting a large r and omized trial of HRT in symptomatic women with early-stage breast cancer . DESIGN Open r and omized study . SETTING Outpatient clinics at The Royal Marsden and St. George 's Hospitals , London . PATIENT(S ) One hundred postmenopausal women with early-stage breast cancer , experiencing vasomotor symptoms and /or vaginal dryness . INTERVENTION(S ) R and omization ( 1:1 ) to HRT or no HRT for 6 months . MAIN OUTCOME MEASURE(S ) Acceptance , continuance rates , and the reasons eligible women declined study entry . RESULT ( S ) Acceptance ( 38.8 % ) and continuance rates ( > 80 % ) were encouraging . The efficacy of HRT did not appear to be antagonized with concomitant tamoxifen . Seventy-five percent of women continued HRT after the study ended . Three women developed metastatic disease . Two used  HRT .  CONCLUSION ( S ) Despite informed consent , a national UK r and omized trial of HRT should be feasible and has now been planned . Successful implementation necessitates the provision of information about HRT and the estrogen deficiency side effects of breast cancer therapy to health professionals and women with breast cancer CONTEXT Despite decades of accumulated observational evidence , the balance of risks and benefits for hormone use in healthy postmenopausal women remains uncertain . OBJECTIVE To assess the major health benefits and risks of the most commonly used combined hormone preparation in the United States . DESIGN Estrogen plus progestin component of the Women 's Health Initiative , a r and omized controlled primary prevention trial ( planned duration , 8.5 years ) in which 16608 postmenopausal women aged 50 - 79 years with an intact uterus at baseline were recruited by 40 US clinical centers in 1993 - 1998 . INTERVENTIONS Participants received conjugated equine estrogens , 0.625 mg/d , plus medroxyprogesterone acetate , 2.5 mg/d , in 1 tablet ( n = 8506 ) or placebo ( n = 8102 ) . MAIN OUTCOMES MEASURES The primary outcome was coronary heart disease ( CHD ) ( nonfatal myocardial infa rct ion and CHD death ) , with invasive breast cancer as the primary adverse outcome . A global index summarizing the balance of risks and benefits included the 2 primary outcomes plus stroke , pulmonary embolism ( PE ) , endometrial cancer , colorectal cancer , hip fracture , and death due to other causes . RESULTS On May 31 , 2002 , after a mean of 5.2 years of follow-up , the data and safety monitoring board recommended stopping the trial of estrogen plus progestin vs placebo because the test statistic for invasive breast cancer exceeded the stopping boundary for this adverse effect and the global index statistic supported risks exceeding benefits . This report includes data on the major clinical outcomes through April 30 , 2002 . Estimated hazard ratios ( HRs ) ( nominal 95 % confidence intervals [ CIs ] ) were as follows : CHD , 1.29 ( 1.02 - 1.63 ) with 286 cases ; breast cancer , 1.26 ( 1.00 - 1.59 ) with 290 cases ; stroke , 1.41 ( 1.07 - 1.85 ) with 212 cases ; PE , 2.13 ( 1.39 - 3.25 ) with 101 cases ; colorectal cancer , 0.63 ( 0.43 - 0.92 ) with 112 cases ; endometrial cancer , 0.83 ( 0.47 - 1.47 ) with 47 cases ; hip fracture , 0.66 ( 0.45 - 0.98 ) with 106 cases ; and death due to other causes , 0.92 ( 0.74 - 1.14 ) with 331 cases . Corresponding HRs ( nominal 95 % CIs ) for composite outcomes were 1.22 ( 1.09 - 1.36 ) for total cardiovascular disease ( arterial and venous disease ) , 1.03 ( 0.90 - 1.17 ) for total cancer , 0.76 ( 0.69 - 0.85 ) for combined fractures , 0.98 ( 0.82 - 1.18 ) for total mortality , and 1.15 ( 1.03 - 1.28 ) for the global index . Absolute excess risks per 10 000 person-years attributable to estrogen plus progestin were 7 more CHD events , 8 more strokes , 8 more PEs , and 8 more invasive breast cancers , while absolute risk reductions per 10 000 person-years were 6 fewer colorectal cancers and 5 fewer hip fractures . The absolute excess risk of events included in the global index was 19 per 10 000 person-years . CONCLUSIONS Overall health risks exceeded benefits from use of combined estrogen plus progestin for an average 5.2-year follow-up among healthy postmenopausal US women .  All-cause mortality was not affected during the trial . The risk-benefit profile found in this trial is not consistent with the requirements for a viable intervention for primary prevention of chronic diseases , and the results indicate that this regimen should not be initiated or continued for primary prevention of CHD OBJECTIVE To determine whether estrogen replacement therapy ( ERT ) adversely affected outcome of breast cancer survivors . METHOD A prospect i ve descriptive study of all breast cancer survivors who requested ERT because of intractable menopausal symptoms . All patients presented voluntarily as gynecological out patients and were all given oral continuous opposed ERT : 20 premarin and medroxyprogesterone and four 
    Output:
    
There are currently no reassuring data indicating the absence of a harmful effect of HT .