RESUMEN
BACKGROUND: Two large clinical trials have shown a reduced rate of breast cancer development in high-risk women in the initial 5 years of follow-up after use of aromatase inhibitors (MAP.3 and International Breast Cancer Intervention Study II [IBIS-II]). Here, we report blinded long-term follow-up results for the IBIS-II trial, which compared anastrozole with placebo, with the objective of determining the efficacy of anastrozole for preventing breast cancer (both invasive and ductal carcinoma in situ) in the post-treatment period. METHODS: IBIS-II is an international, randomised, double-blind, placebo-controlled trial. Postmenopausal women at increased risk of developing breast cancer were recruited and were randomly assigned (1:1) to either anastrozole (1 mg per day, oral) or matching placebo daily for 5 years. After treatment completion, women were followed on a yearly basis to collect data on breast cancer incidence, death, other cancers, and major adverse events (cardiovascular events and fractures). The primary outcome was all breast cancer. FINDINGS: 3864 women were recruited between Feb 2, 2003, and Jan 31, 2012. 1920 women were randomly assigned to 5 years anastrozole and 1944 to placebo. After a median follow-up of 131 months (IQR 105-156), a 49% reduction in breast cancer was observed for anastrozole (85 vs 165 cases, hazard ratio [HR] 0·51, 95% CI 0·39-0·66, p<0·0001). The reduction was larger in the first 5 years (35 vs 89, 0·39, 0·27-0·58, p<0·0001), but still significant after 5 years (50 vs 76 new cases, 0·64, 0·45-0·91, p=0·014), and not significantly different from the first 5 years (p=0·087). Invasive oestrogen receptor-positive breast cancer was reduced by 54% (HR 0·46, 95% CI 0·33-0·65, p<0·0001), with a continued significant effect in the period after treatment. A 59% reduction in ductal carcinoma in situ was observed (0·41, 0·22-0·79, p=0·0081), especially in participants known to be oestrogen receptor-positive (0·22, 0·78-0·65, p<0·0001). No significant difference in deaths was observed overall (69 vs 70, HR 0·96, 95% CI 0·69-1·34, p=0·82) or for breast cancer (two anastrozole vs three placebo). A significant decrease in non-breast cancers was observed for anastrozole (147 vs 200, odds ratio 0·72, 95% CI 0·57-0·91, p=0·0042), owing primarily to non-melanoma skin cancer. No excess of fractures or cardiovascular disease was observed. INTERPRETATION: This analysis has identified a significant continuing reduction in breast cancer with anastrozole in the post-treatment follow-up period, with no evidence of new late side-effects. Further follow-up is needed to assess the effect on breast cancer mortality. FUNDING: Cancer Research UK, the National Health and Medical Research Council Australia, Breast Cancer Research Foundation, Sanofi Aventis, and AstraZeneca.
Asunto(s)
Anastrozol/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/prevención & control , Administración Oral , Adulto , Anciano , Anastrozol/efectos adversos , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/mortalidad , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/tratamiento farmacológico , Carcinoma Intraductal no Infiltrante/patología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Persona de Mediana Edad , Placebos , Resultado del Tratamiento , Reino Unido/epidemiologíaRESUMEN
Background and Purpose- Stroke incidence in younger and middle-aged people is growing. Despite this, its associations in this subset of the stroke population are unknown, and prevention strategies are not tailored to meet their needs. This study examined the association between self-reported walking pace and incident stroke. Methods- Data from the UK Biobank were used in a prospective population-based study. Three hundred and sixty-three thousand, one hundred and thirty-seven participants aged 37 to 73 years (52% women) were recruited. The associations of self-reported walking pace with stroke incidence over follow-up were investigated using Cox proportional-hazard models. Results- Among 363,137 participants, 2705 (0.7%) participants developed a fatal or nonfatal stroke event over the mean follow-up period of 6.1 years (interquartile range, 5.4-6.7). Slow walking pace was associated with a higher hazard for stroke incidence (hazard ratio [HR], 1.45 [95% CI, 1.26-1.66]; P<0.0001). Stroke incidence was not associated with walking pace among people <65 years of age. However, slow walking pace was associated with a higher risk of stroke among participants aged ≥65 years (HR, 1.42 [95% CI, 1.17-1.72]; P<0.0001). A higher risk for stroke was observed on those with middle (HR, 1.28 [95% CI, 1.01-1.63]; P=0.039) and higher (HR, 1.29 [95% CI, 1.05-1.69]; P=0.012) deprivation levels but not in the least deprived individuals. Similarly, overweight (HR, 1.30 [95% CI, 1.04-1.63]; P=0.019) and obese (HR, 1.33 [95% CI, 1.09-1.63]; P=0.004) but not normal-weight individuals had a higher risk of stroke incidence. Conclusions- Slow walking pace was associated with a higher risk of stroke among participants over 64 years of age in this population-based cohort study. The addition of the measurement of self-reported walking pace to primary care or public health clinical consultations may be a useful screening tool for stroke risk.
Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Accidente Cerebrovascular/epidemiología , Velocidad al Caminar/fisiología , Caminata/fisiología , Adulto , Anciano , Bancos de Muestras Biológicas , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Estudios Prospectivos , Factores de Riesgo , Reino Unido/epidemiologíaRESUMEN
BACKGROUND: Ovarian failure is a common toxic effect of chemotherapy. Studies of the use of gonadotropin-releasing hormone (GnRH) agonists to protect ovarian function have shown mixed results and lack data on pregnancy outcomes. METHODS: We randomly assigned 257 premenopausal women with operable hormone-receptor-negative breast cancer to receive standard chemotherapy with the GnRH agonist goserelin (goserelin group) or standard chemotherapy without goserelin (chemotherapy-alone group). The primary study end point was the rate of ovarian failure at 2 years, with ovarian failure defined as the absence of menses in the preceding 6 months and levels of follicle-stimulating hormone (FSH) in the postmenopausal range. Rates were compared with the use of conditional logistic regression. Secondary end points included pregnancy outcomes and disease-free and overall survival. RESULTS: At baseline, 218 patients were eligible and could be evaluated. Among 135 with complete primary end-point data, the ovarian failure rate was 8% in the goserelin group and 22% in the chemotherapy-alone group (odds ratio, 0.30; 95% confidence interval [CI], 0.09 to 0.97; two-sided P=0.04). Owing to missing primary end-point data, sensitivity analyses were performed, and the results were consistent with the main findings. Missing data did not differ according to treatment group or according to the stratification factors of age and planned chemotherapy regimen. Among the 218 patients who could be evaluated, pregnancy occurred in more women in the goserelin group than in the chemotherapy-alone group (21% vs. 11%, P=0.03); women in the goserelin group also had improved disease-free survival (P=0.04) and overall survival (P=0.05). CONCLUSIONS: Although missing data weaken interpretation of the findings, administration of goserelin with chemotherapy appeared to protect against ovarian failure, reducing the risk of early menopause and improving prospects for fertility. (Funded by the National Cancer Institute and others; POEMS/S0230 ClinicalTrials.gov number, NCT00068601.).
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Hormona Liberadora de Gonadotropina/agonistas , Goserelina/uso terapéutico , Insuficiencia Ovárica Primaria/prevención & control , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Goserelina/efectos adversos , Humanos , Persona de Mediana Edad , Embarazo , Índice de Embarazo , Premenopausia , Insuficiencia Ovárica Primaria/inducido químicamente , Análisis de RegresiónRESUMEN
BACKGROUND: Third-generation aromatase inhibitors are more effective than tamoxifen for preventing recurrence in postmenopausal women with hormone-receptor-positive invasive breast cancer. However, it is not known whether anastrozole is more effective than tamoxifen for women with hormone-receptor-positive ductal carcinoma in situ (DCIS). Here, we compare the efficacy of anastrozole with that of tamoxifen in postmenopausal women with hormone-receptor-positive DCIS. METHODS: In a double-blind, multicentre, randomised placebo-controlled trial, we recruited women who had been diagnosed with locally excised, hormone-receptor-positive DCIS. Eligible women were randomly assigned in a 1:1 ratio by central computer allocation to receive 1 mg oral anastrozole or 20 mg oral tamoxifen every day for 5 years. Randomisation was stratified by major centre or hub and was done in blocks (six, eight, or ten). All trial personnel, participants, and clinicians were masked to treatment allocation and only the trial statistician had access to treatment allocation. The primary endpoint was all recurrence, including recurrent DCIS and new contralateral tumours. All analyses were done on a modified intention-to-treat basis (in all women who were randomised and did not revoke consent for their data to be included) and proportional hazard models were used to compute hazard ratios and corresponding confidence intervals. This trial is registered at the ISRCTN registry, number ISRCTN37546358. RESULTS: Between March 3, 2003, and Feb 8, 2012, we enrolled 2980 postmenopausal women from 236 centres in 14 countries and randomly assigned them to receive anastrozole (1449 analysed) or tamoxifen (1489 analysed). Median follow-up was 7·2 years (IQR 5·6-8·9), and 144 breast cancer recurrences were recorded. We noted no statistically significant difference in overall recurrence (67 recurrences for anastrozole vs 77 for tamoxifen; HR 0·89 [95% CI 0·64-1·23]). The non-inferiority of anastrozole was established (upper 95% CI <1·25), but its superiority to tamoxifen was not (p=0·49). A total of 69 deaths were recorded (33 for anastrozole vs 36 for tamoxifen; HR 0·93 [95% CI 0·58-1·50], p=0·78), and no specific cause was more common in one group than the other. The number of women reporting any adverse event was similar between anastrozole (1323 women, 91%) and tamoxifen (1379 women, 93%); the side-effect profiles of the two drugs differed, with more fractures, musculoskeletal events, hypercholesterolaemia, and strokes with anastrozole and more muscle spasm, gynaecological cancers and symptoms, vasomotor symptoms, and deep vein thromboses with tamoxifen. CONCLUSIONS: No clear efficacy differences were seen between the two treatments. Anastrozole offers another treatment option for postmenopausal women with hormone-receptor-positive DCIS, which may be be more appropriate for some women with contraindications for tamoxifen. Longer follow-up will be necessary to fully evaluate treatment differences. FUNDING: Cancer Research UK, National Health and Medical Research Council Australia, Breast Cancer Research Fund, AstraZeneca, Sanofi Aventis.
Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/prevención & control , Carcinoma Ductal de Mama/prevención & control , Recurrencia Local de Neoplasia/prevención & control , Nitrilos/uso terapéutico , Tamoxifeno/uso terapéutico , Triazoles/uso terapéutico , Administración Oral , Anastrozol , Antineoplásicos Hormonales/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/cirugía , Método Doble Ciego , Femenino , Humanos , Análisis de Intención de Tratar , Persona de Mediana Edad , Nitrilos/administración & dosificación , Nitrilos/efectos adversos , Posmenopausia , Tamoxifeno/administración & dosificación , Tamoxifeno/efectos adversos , Triazoles/administración & dosificación , Triazoles/efectos adversosRESUMEN
BACKGROUND: To examine the effect on cognitive function of adjuvant ovarian function suppression (OFS) for breast cancer. METHODS: The Suppression of Ovarian Function (SOFT) trial randomised premenopausal women with hormone receptor-positive breast cancer to 5 years adjuvant endocrine therapy with tamoxifen+OFS, exemestane+OFS or tamoxifen alone. The Co-SOFT substudy assessed objective cognitive function and patient reported outcomes at randomisation (T0), and 1 year later (T1); the primary endpoint was change in global cognitive function, measured by the composite objective cognitive function score. Data were compared for the pooled tamoxifen+OFS and exemestane+OFS groups vs the tamoxifen alone group using the Wilcoxon rank-sum test. RESULTS: Of 86 participants, 74 underwent both T0 and T1 cognitive testing; 54 randomised to OFS+ either tamoxifen (28) or exemestane (26) and 20 randomised to tamoxifen alone. There was no significant difference in the changes in the composite cognitive function scores between the OFS+ tamoxifen or exemestane groups and the tamoxifen group (mean±s.d., -0.21±0.92 vs -0.04±0.49, respectively, P=0.71, effect size=-0.20), regardless of prior chemotherapy status, and adjusting for baseline characteristics. CONCLUSIONS: The Co-SOFT study, although limited by small samples size, provides no evidence that adding OFS to adjuvant oral endocrine therapy substantially affects global cognitive function.
Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/complicaciones , Ovario/metabolismo , Tamoxifeno/uso terapéutico , Adyuvantes Inmunológicos , Adulto , Neoplasias de la Mama/tratamiento farmacológico , Cognición , Femenino , Humanos , Persona de Mediana Edad , Premenopausia , Calidad de VidaRESUMEN
BACKGROUND: Aromatase inhibitor induced musculoskeletal syndrome is experienced by approximately half of women taking aromatase inhibitors, impairing quality of life and leading some to discontinue treatment. Evidence for effective treatments is lacking. We aimed to understand the manifestations and impact of this syndrome in the Australian breast cancer community, and strategies used for its management. METHODS: A survey invitation was sent to 2390 members of the Breast Cancer Network Australia Review and Survey Group in April 2014. The online questionnaire included 45 questions covering demographics, aromatase inhibitor use, clinical manifestations and risk factors for the aromatase inhibitor musculoskeletal syndrome, reasons for treatment discontinuation and efficacy of interventions used. RESULTS: Aromatase inhibitor induced musculoskeletal syndrome was reported by 302 (82 %) of 370 respondents. Twenty-seven percent had discontinued treatment for any reason and of these, 68 % discontinued because of the musculoskeletal syndrome. Eighty-one percent had used at least one intervention from the following three categories to manage the syndrome: doctor prescribed medications, over-the-counter/complementary medicines or alternative/non-drug therapies. Anti-inflammatories, paracetamol (acetaminophen) and yoga were most successful in relieving symptoms in each of the respective categories. Almost a third of respondents reported that one or more interventions helped prevent aromatase inhibitor discontinuation. However, approximately 20 % of respondents found no intervention effective in any category. CONCLUSION: We conclude that aromatase inhibitor induced musculoskeletal syndrome is a significant issue for Australian women and is an important reason for treatment discontinuation. Women use a variety of interventions to manage this syndrome; however, their efficacy appears limited.
Asunto(s)
Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Enfermedades Musculoesqueléticas/inducido químicamente , Enfermedades Musculoesqueléticas/epidemiología , Australia/epidemiología , Neoplasias de la Mama/epidemiología , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/terapia , Calidad de Vida , Encuestas y Cuestionarios , Síndrome , Resultado del TratamientoRESUMEN
BACKGROUND: Four previously published randomised clinical trials have shown that tamoxifen can reduce the risk of breast cancer in healthy women at increased risk of breast cancer in the first 10 years of follow-up. We report the long-term follow-up of the IBIS-I trial, in which the participants and investigators remain largely masked to treatment allocation. METHODS: In the IBIS-I randomised controlled trial, premenopausal and postmenopausal women 35-70 years of age deemed to be at an increased risk of developing breast cancer were randomly assigned (1:1) to receive oral tamoxifen 20 mg daily or matching placebo for 5 years. Patients were randomly assigned to the two treatment groups by telephone or fax according to a block randomisation schedule (permuted block sizes of six or ten). Patients and investigators were masked to treatment assignment by use of central randomisation and coded drug supply. The primary endpoint was the occurrence of breast cancer (invasive breast cancer and ductal carcinoma in situ), analysed by intention to treat. Cox proportional hazard models were used to assess breast cancer occurrence and mortality. The trial is closed to recruitment and active treatment is completed, but long-term follow-up is ongoing. This trial is registered with controlledtrials.com, number ISRCTN91879928. FINDINGS: Between April 14, 1992, and March 30, 2001, 7154 eligible women recruited from genetics clinics and breast care clinics in eight countries were enrolled into the IBIS-I trial and were randomly allocated to the two treatment groups: 3579 to tamoxifen and 3575 to placebo. After a median follow up of 16.0 years (IQR 14.1-17.6), 601 breast cancers have been reported (251 [7.0%] in 3579 patients in the tamoxifen group vs 350 [9.8%] in 3575 women in the placebo group; hazard ratio [HR] 0.71 [95% CI 0.60-0.83], p<0.0001). The risk of developing breast cancer was similar between years 0-10 (226 [6.3%] in 3575 women in the placebo group vs 163 [4.6%] in 3579 women in the tamoxifen group; hazard ratio [HR] 0.72 [95% CI 0.59-0.88], p=0.001) and after 10 years (124 [3.8%] in 3295 women vs 88 [2.6%] in 3343, respectively; HR 0.69 [0.53-0.91], p=0.009). The greatest reduction in risk was seen in invasive oestrogen receptor-positive breast cancer (HR 0.66 [95% CI 0.54-0.81], p<0.0001) and ductal carcinoma in situ (0.65 [0.43-1.00], p=0.05), but no effect was noted for invasive oestrogen receptor-negative breast cancer (HR 1.05 [95% CI 0.71-1.57], p=0.8). INTERPRETATION: These results show that tamoxifen offers a very long period of protection after treatment cessation, and thus substantially improves the benefit-to-harm ratio of the drug for breast cancer prevention. FUNDING: Cancer Research UK (UK) and the National Health and Medical Research Council (Australia).
Asunto(s)
Anticarcinógenos/administración & dosificación , Neoplasias de la Mama/prevención & control , Carcinoma Intraductal no Infiltrante/prevención & control , Tamoxifeno/administración & dosificación , Administración Oral , Adulto , Anciano , Anticarcinógenos/efectos adversos , Australia , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/química , Neoplasias de la Mama/etiología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/química , Carcinoma Intraductal no Infiltrante/etiología , Carcinoma Intraductal no Infiltrante/mortalidad , Carcinoma Intraductal no Infiltrante/patología , Esquema de Medicación , Europa (Continente) , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Invasividad Neoplásica , Nueva Zelanda , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Receptores de Estrógenos/análisis , Medición de Riesgo , Factores de Riesgo , Tamoxifeno/efectos adversos , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Aromatase inhibitors effectively prevent breast cancer recurrence and development of new contralateral tumours in postmenopausal women. We assessed the efficacy and safety of the aromatase inhibitor anastrozole for prevention of breast cancer in postmenopausal women who are at high risk of the disease. METHODS: Between Feb 2, 2003, and Jan 31, 2012, we recruited postmenopausal women aged 40-70 years from 18 countries into an international, double-blind, randomised placebo-controlled trial. To be eligible, women had to be at increased risk of breast cancer (judged on the basis of specific criteria). Eligible women were randomly assigned (1:1) by central computer allocation to receive 1 mg oral anastrozole or matching placebo every day for 5 years. Randomisation was stratified by country and was done with blocks (size six, eight, or ten). All trial personnel, participants, and clinicians were masked to treatment allocation; only the trial statistician was unmasked. The primary endpoint was histologically confirmed breast cancer (invasive cancers or non-invasive ductal carcinoma in situ). Analyses were done by intention to treat. This trial is registered, number ISRCTN31488319. FINDINGS: 1920 women were randomly assigned to receive anastrozole and 1944 to placebo. After a median follow-up of 5·0 years (IQR 3·0-7·1), 40 women in the anastrozole group (2%) and 85 in the placebo group (4%) had developed breast cancer (hazard ratio 0·47, 95% CI 0·32-0·68, p<0·0001). The predicted cumulative incidence of all breast cancers after 7 years was 5·6% in the placebo group and 2·8% in the anastrozole group. 18 deaths were reported in the anastrozole group and 17 in the placebo group, and no specific causes were more common in one group than the other (p=0·836). INTERPRETATION: Anastrozole effectively reduces incidence of breast cancer in high-risk postmenopausal women. This finding, along with the fact that most of the side-effects associated with oestrogen deprivation were not attributable to treatment, provides support for the use of anastrozole in postmenopausal women at high risk of breast cancer. FUNDING: Cancer Research UK, the National Health and Medical Research Council Australia, Sanofi-Aventis, and AstraZeneca.
Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/prevención & control , Carcinoma Ductal de Mama/prevención & control , Carcinoma Intraductal no Infiltrante/prevención & control , Carcinoma Lobular/prevención & control , Nitrilos/uso terapéutico , Triazoles/uso terapéutico , Adulto , Anciano , Anastrozol , Método Doble Ciego , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Posmenopausia , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del TratamientoRESUMEN
ABSTRACT Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18-20 February 2014 The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the first of a two part conference scene, consensus recommendations for axillary management are presented and focus on the following topics: indications for completion axillary lymph node dissection in primary surgical patients with ≤2 macrometastases or any sentinel nodal deposits after PST; the timing of sentinel lymph node biopsy in the context of PST; use of axillary irradiation as a component of primary treatment plans and the role of intraoperative node assessment in the post-Z0011 era.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Medicina de Precisión , Manejo de la Enfermedad , Femenino , HumanosRESUMEN
Kyoto Breast Cancer Consensus Conference, Kyoto, Japan, 18-20 February 2014 The loco-regional management of breast cancer is increasingly complex with application of primary systemic therapies, oncoplastic techniques and genetic testing for breast cancer susceptibility. Personalization of loco-regional treatment is integral to optimization of breast cancer care. Clinical and pathological tumor stage, biological features and host factors influence loco-regional treatment strategies and extent of surgical procedures. Key issues including axillary staging, axillary treatment, radiation therapy, primary systemic therapy (PST), preoperative hormonal therapy and genetic predisposition were identified and discussed at the Kyoto Breast Cancer Consensus Conference (KBCCC2014). In the second of a two part conference scene, consensus recommendations for radiation treatment, primary systemic therapies and management of genetic predisposition are reported and focus on the following topics: influence of both clinical response to PST and stage at presentation on recommendations for postmastectomy radiotherapy; use of regional nodal irradiation in selected node-positive patients and those with adverse pathological factors; extent of surgical resection following downstaging of tumors with PST; use of preoperative hormonal therapy in premenopausal women with larger, node-negative luminal A-like tumors and managing increasing demands for contralateral prophylactic mastectomy in patients with a unilateral sporadic breast cancer.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Medicina de Precisión , Manejo de la Enfermedad , Femenino , HumanosRESUMEN
BACKGROUND: Aromatase inhibitors prevent breast cancer in postmenopausal women at high risk of the disease but are associated with accelerated bone loss. We assessed effectiveness of oral risedronate for prevention of reduction in bone mineral density (BMD) after 3 years of follow-up in a subset of patients in the IBIS-II trial. METHODS: The double-blind IBIS-II trial recruited 3864 healthy, postmenopausal women at increased risk of breast cancer and randomly allocated them oral anastrozole (1 mg/day) or matched placebo. 1410 (36%) postmenopausal women were then enrolled in a bone substudy and stratified at baseline according to their lowest baseline T score at spine or femoral neck (stratum I: T score at least -1·0; stratum II: T score at least -2·5 but less than -1·0; stratum III: T score less than -2·5 but greater than -4·0). Women in stratum I were monitored only; women in stratum III were all given risedronate (35 mg/week). Women in stratum II were randomly assigned (1:1) to risedronate (35 mg/week) or matched placebo by use of a block randomisation schedule via a web-based programme. The primary outcome of this per-protocol analysis (done with all women with a baseline and 3 year DXA assessment) was the effect of risedronate versus placebo for osteopenic women in stratum II randomly allocated to anastrozole (1 mg/day). Secondary outcomes included effect of anastrozole (1 mg/day) on BMD in women not receiving risedronate (strata I and II) and in osteoporotic women who were all treated with risedronate (stratum III). The trial is ongoing, but no longer recruiting. This trial is registered, number ISRCTN31488319. FINDINGS: Between Feb 2, 2003, and Sept 30, 2010, 150 (58%) of 260 women in stratum II who had been randomly allocated to anastrozole and either risedronate or placebo had baseline and 3 year assessments. At the lumbar spine, 3 year mean BMD change for the 77 women receiving anastrozole/risedronate was 1·1% (95% CI 0·2 to 2·1) versus -2·6% (-4·0 to -1·3) for the 73 women receiving anastrozole/placebo (p<0·0001). For the total hip, 3 year mean BMD change for women receiving anastrozole/risedronate was -0·7% (-1·6 to 0·2) versus -3·5% (-4·6 to -2·3) for women receiving anastrozole/placebo (p=0·0001). 652 (65%) of 1008 women in strata I and II who were not randomly allocated to risedronate had both baseline and 3 year assessments. Women not receiving risedronate in stratum I and II who received anastrozole (310 women) had a significant BMD decrease after 3 years of follow-up compared with women who received placebo (342 women) at the lumbar spine (-4·0% [-4·5 to -3·4] vs -1·2% [-1·7 to -0·7], p<0·0001) and total hip (-4·0% [-4·4 to -3·6] vs -1·8% [-2·1 to -1·4], p<0·0001). 106 (79%) of 149 women in stratum III had a baseline and a 3 year assessment. The 46 women allocated to anastrozole had a modest BMD increase of 1·2% (-0·1 to 2·6) at the spine compared with a 3·9% (2·6 to 5·2) increase for the 60 women allocated to placebo (p=0·006). For the total hip, a small 0·3% (-0·9 to 1·5) increase was noted for women allocated anastrozole compared with a 1·5% (0·5 to 2·5) increase for women allocated placebo, but the difference was not significant (p=0·12). The most common adverse event reported was arthralgia (stratum I: 94 placebo and 114 anastrozole; stratum II: 39 placebo/placebo, 25 placebo/risedronate, 34 anastrozole/placebo, and 34 anastrozole/risedronate; stratum III: 21 placebo/risedronate, 17 anastrozole/risedronate). Other adverse events included hot flushes, alopecia, abdominal pain, and back pain. INTERPRETATION: Risedronate counterbalances the effect of anastrozole-induced bone loss in osteopenic and osteoporotic women and might be offered in combination with anastrozole treatment to provide an improved risk-benefit profile. FUNDING: Cancer Research UK (C569/A5032), National Health and Medical Research Council Australia (GNT300755, GNT569213), Sanofi-Aventis, and AstraZeneca.
Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Ácido Etidrónico/análogos & derivados , Nitrilos/uso terapéutico , Osteoporosis/tratamiento farmacológico , Posmenopausia/efectos de los fármacos , Triazoles/uso terapéutico , Adulto , Anciano , Anastrozol , Método Doble Ciego , Ácido Etidrónico/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Agencias Internacionales , Persona de Mediana Edad , Osteoporosis/patología , Pronóstico , Ácido RisedrónicoRESUMEN
BACKGROUND: Tamoxifen and raloxifene reduce the risk of breast cancer in women at elevated risk of disease, but the duration of the effect is unknown. We assessed the effectiveness of selective oestrogen receptor modulators (SERMs) on breast cancer incidence. METHODS: We did a meta-analysis with individual participant data from nine prevention trials comparing four selective oestrogen receptor modulators (SERMs; tamoxifen, raloxifene, arzoxifene, and lasofoxifene) with placebo, or in one study with tamoxifen. Our primary endpoint was incidence of all breast cancer (including ductal carcinoma in situ) during a 10 year follow-up period. Analysis was by intention to treat. RESULTS: We analysed data for 83,399 women with 306,617 women-years of follow-up. Median follow-up was 65 months (IQR 54-93). Overall, we noted a 38% reduction (hazard ratio [HR] 0·62, 95% CI 0·56-0·69) in breast cancer incidence, and 42 women would need to be treated to prevent one breast cancer event in the first 10 years of follow-up. The reduction was larger in the first 5 years of follow-up than in years 5-10 (42%, HR 0·58, 0·51-0·66; p<0·0001 vs 25%, 0·75, 0·61-0·93; p=0·007), but we noted no heterogeneity between time periods. Thromboembolic events were significantly increased with all SERMs (odds ratio 1·73, 95% CI 1·47-2·05; p<0·0001). We recorded a significant reduction of 34% in vertebral fractures (0·66, 0·59-0·73), but only a small effect for non-vertebral fractures (0·93, 0·87-0·99). INTERPRETATION: For all SERMs, incidence of invasive oestrogen (ER)-positive breast cancer was reduced both during treatment and for at least 5 years after completion. Similar to other preventive interventions, careful consideration of risks and benefits is needed to identify women who are most likely to benefit from these drugs. FUNDING: Cancer Research UK.
Asunto(s)
Anticarcinógenos/uso terapéutico , Neoplasias de la Mama/prevención & control , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Femenino , Humanos , Estimación de Kaplan-Meier , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: For women with oestrogen receptor (ER)-positive early breast cancer, treatment with tamoxifen for 5 years substantially reduces the breast cancer mortality rate throughout the first 15 years after diagnosis. We aimed to assess the further effects of continuing tamoxifen to 10 years instead of stopping at 5 years. METHODS: In the worldwide Adjuvant Tamoxifen: Longer Against Shorter (ATLAS) trial, 12,894 women with early breast cancer who had completed 5 years of treatment with tamoxifen were randomly allocated to continue tamoxifen to 10 years or stop at 5 years (open control). Allocation (1:1) was by central computer, using minimisation. After entry (between 1996 and 2005), yearly follow-up forms recorded any recurrence, second cancer, hospital admission, or death. We report effects on breast cancer outcomes among the 6846 women with ER-positive disease, and side-effects among all women (with positive, negative, or unknown ER status). Long-term follow-up still continues. This study is registered, number ISRCTN19652633. FINDINGS: Among women with ER-positive disease, allocation to continue tamoxifen reduced the risk of breast cancer recurrence (617 recurrences in 3428 women allocated to continue vs 711 in 3418 controls, p=0·002), reduced breast cancer mortality (331 deaths vs 397 deaths, p=0·01), and reduced overall mortality (639 deaths vs 722 deaths, p=0·01). The reductions in adverse breast cancer outcomes appeared to be less extreme before than after year 10 (recurrence rate ratio [RR] 0·90 [95% CI 0·791·02] during years 59 and 0·75 [0·620·90] in later years; breast cancer mortality RR 0·97 [0·791·18] during years 59 and 0·71 [0·580·88] in later years). The cumulative risk of recurrence during years 514 was 21·4% for women allocated to continue versus 25·1% for controls; breast cancer mortality during years 514 was 12·2% for women allocated to continue versus 15·0% for controls (absolute mortality reduction 2·8%). Treatment allocation seemed to have no effect on breast cancer outcome among 1248 women with ER-negative disease, and an intermediate effect among 4800 women with unknown ER status. Among all 12,894 women, mortality without recurrence from causes other than breast cancer was little affected (691 deaths without recurrence in 6454 women allocated to continue versus 679 deaths in 6440 controls; RR 0·99 [0·891·10]; p=0·84). For the incidence (hospitalisation or death) rates of specific diseases, RRs were as follows: pulmonary embolus 1·87 (95% CI 1·133·07, p=0·01 [including 0·2% mortality in both treatment groups]), stroke 1·06 (0·831·36), ischaemic heart disease 0·76 (0·600·95, p=0·02), and endometrial cancer 1·74 (1·302·34, p=0·0002). The cumulative risk of endometrial cancer during years 514 was 3·1% (mortality 0·4%) for women allocated to continue versus 1·6% (mortality 0·2%) for controls (absolute mortality increase 0·2%). INTERPRETATION: For women with ER-positive disease, continuing tamoxifen to 10 years rather than stopping at 5 years produces a further reduction in recurrence and mortality, particularly after year 10. These results, taken together with results from previous trials of 5 years of tamoxifen treatment versus none, suggest that 10 years of tamoxifen treatment can approximately halve breast cancer mortality during the second decade after diagnosis. FUNDING: Cancer Research UK, UK Medical Research Council, AstraZeneca UK, US Army, EU-Biomed.
Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Tamoxifeno/administración & dosificación , Adulto , Anciano , Neoplasias de la Mama/química , Quimioterapia Adyuvante , Femenino , Humanos , Persona de Mediana Edad , Receptores de Estrógenos/análisis , Factores de TiempoRESUMEN
BACKGROUND: Breast cancer is the most common malignancy in women world-wide. Triple negative breast cancer (TNBC) is a highly aggressive subtype that lacks expression of hormone receptors for estrogen, progesterone and human epidermal growth factor 2; and is associated with a high propensity for metastatic spread. Several studies have identified critical roles for microRNAs in breast cancer, but the role of two critical enzymes involved in microRNA biogenesis, Dicer and Drosha, is not well understood, particularly with respect to metastatic progression in this subtype. METHODS: We examined the expression of Dicer and Drosha in a series of invasive 35 TNBCs with matched normal adjacent tissues (n = 18) and lymph node metastases (n = 15) using semi-quantitative real time RT-PCR. The relationship of their expression with clinical features including age at diagnosis, lymph node positivity and tumour size was analysed. RESULTS: We report that Dicer was significantly decreased while Drosha was significantly increased in tumours when compared to normal adjacent tissues. While there was no difference in Drosha expression in lymph node metastases when compared to the primary tumour, Dicer was significantly increased. There was no correlation between the expression of either Dicer or Drosha to age at diagnosis, lymph node positivity and tumour size. CONCLUSIONS: In conclusion, Dicer and Drosha are dysregulated in TNBC and matched lymph node metastases however, the clinical relevance of this is still not known. The altered expression of Dicer and Drosha may serve as markers for disrupted miRNA biogenesis in TNBC.
Asunto(s)
Biomarcadores de Tumor/biosíntesis , ARN Helicasas DEAD-box/biosíntesis , Ribonucleasa III/biosíntesis , Neoplasias de la Mama Triple Negativas/genética , ARN Helicasas DEAD-box/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática/genética , Pronóstico , Ribonucleasa III/genética , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
BACKGROUND: Breast cancer is the most common malignancy that develops in women, responsible for the highest cancer-associated death rates. Triple negative breast cancers represent an important subtype that have an aggressive clinical phenotype, are associated with a higher likelihood of metastasis and are not responsive to current targeted therapies. miRNAs have emerged as an attractive candidate for molecular biomarkers and treatment targets in breast cancer, but their role in the progression of triple negative breast cancer remains largely unexplored. METHODS: This study has investigated miRNA expression profiles in 31 primary triple negative breast cancer cases and in 13 matched lymph node metastases compared with 23 matched normal breast tissues to determine miRNAs associated with the initiation of this disease subtype and those associated with its metastasis. RESULTS: 71 miRNAs were differentially expressed in triple negative breast cancer, the majority of which have previously been associated with breast cancer, including members of the miR-200 family and the miR-17-92 oncogenic cluster, suggesting that the majority of miRNAs involved in the initiation of triple negative breast cancer are not subtype specific. However, the repertoire of miRNAs expressed in lymph node negative and lymph node positive triple negative breast cancers were largely distinct from one another. In particular, miRNA profiles associated with lymph node negative disease tended to be up-regulated, while those associated with lymph node positive disease were down-regulated and largely overlapped with the profiles of their matched lymph node metastases. From this, 27 miRNAs were identified that are associated with metastatic capability in the triple negative breast cancer subtype. CONCLUSIONS: These results provide novel insight into the repertoire of miRNAs that contribute to the initiation of and progression to lymph node metastasis in triple negative breast cancer and have important implications for the treatment of this breast cancer subtype.
Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Ductal de Mama/genética , MicroARNs/genética , Neoplasias de la Mama Triple Negativas/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Biopsia , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/secundario , Estudios de Casos y Controles , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Metástasis Linfática , Persona de Mediana Edad , Fenotipo , Neoplasias de la Mama Triple Negativas/química , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
OBJECTIVES: To compare hemoglobin concentration (Hb), RBC use, and patient outcomes when restrictive or liberal blood transfusion strategies are used to treat anemic (Hb≤90 g/L) critically ill patients of age≥55 years requiring≥4 days of mechanical ventilation in ICU. DESIGN: Parallel-group randomized multicenter pilot trial. SETTING: Six ICUs in the United Kingdom participated between August 2009 and December 2010. PATIENTS: One hundred patients (51 restrictive and 49 liberal groups). INTERVENTIONS: Patients were randomized to a restrictive (Hb trigger, 70 g/L; target, 71-90 g/L) or liberal (90 g/L; target, 91-110 g/L) transfusion strategy for 14 days or the remainder of ICU stay, whichever was longest. MEASUREMENTS AND MAIN RESULTS: Baseline comorbidity rates and illness severity were high, notably for ischemic heart disease (32%). The Hb difference among groups was 13.8 g/L (95% CI, 11.5-16.0 g/L); p<0.0001); mean Hb during intervention was 81.9 (SD, 5.1) versus 95.7 (6.3) g/L; 21.6% fewer patients in the restrictive group were transfused postrandomization (p<0.001) and received a median 1 (95% CI, 1-2; p=0.002) fewer RBC units. Protocol compliance was high. No major differences in organ dysfunction, duration of ventilation, infections, or cardiovascular complications were observed during intensive care and hospital follow-up. Mortality at 180 days postrandomization trended toward higher rates in the liberal group (55%) than in the restrictive group (37%); relative risk was 0.68 (95% CI, 0.44-1.05; p=0.073). This trend remained in a survival model adjusted for age, gender, ischemic heart disease, Acute Physiology and Chronic Health Evaluation II score, and total non-neurologic Sequential Organ Failure Assessment score at baseline (hazard ratio, 0.54 [95% CI, 0.28-1.03]; p=0.061). CONCLUSIONS: A large trial of transfusion strategies in older mechanically ventilated patients is feasible. This pilot trial found a nonsignificant trend toward lower mortality with restrictive transfusion practice.
Asunto(s)
Transfusión Sanguínea/métodos , Enfermedad Crítica , Unidades de Cuidados Intensivos , Respiración Artificial , Anciano , Anciano de 80 o más Años , Anemia/terapia , Intervalos de Confianza , Transfusión de Eritrocitos/estadística & datos numéricos , Femenino , Hemoglobinas/análisis , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Proyectos Piloto , Reino UnidoRESUMEN
BACKGROUND: The aromatase inhibitor letrozole, as compared with tamoxifen, improves disease-free survival among postmenopausal women with receptor-positive early breast cancer. It is unknown whether sequential treatment with tamoxifen and letrozole is superior to letrozole therapy alone. METHODS: In this randomized, phase 3, double-blind trial of the treatment of hormone-receptor-positive breast cancer in postmenopausal women, we randomly assigned women to receive 5 years of tamoxifen monotherapy, 5 years of letrozole monotherapy, or 2 years of treatment with one agent followed by 3 years of treatment with the other. We compared the sequential treatments with letrozole monotherapy among 6182 women and also report a protocol-specified updated analysis of letrozole versus tamoxifen monotherapy in 4922 women. RESULTS: At a median follow-up of 71 months after randomization, disease-free survival was not significantly improved with either sequential treatment as compared with letrozole alone (hazard ratio for tamoxifen followed by letrozole, 1.05; 99% confidence interval [CI], 0.84 to 1.32; hazard ratio for letrozole followed by tamoxifen, 0.96; 99% CI, 0.76 to 1.21). There were more early relapses among women who were assigned to tamoxifen followed by letrozole than among those who were assigned to letrozole alone. The updated analysis of monotherapy showed that there was a nonsignificant difference in overall survival between women assigned to treatment with letrozole and those assigned to treatment with tamoxifen (hazard ratio for letrozole, 0.87; 95% CI, 0.75 to 1.02; P=0.08). The rate of adverse events was as expected on the basis of previous reports of letrozole and tamoxifen therapy. CONCLUSIONS: Among postmenopausal women with endocrine-responsive breast cancer, sequential treatment with letrozole and tamoxifen, as compared with letrozole monotherapy, did not improve disease-free survival. The difference in overall survival with letrozole monotherapy and tamoxifen monotherapy was not statistically significant. (ClinicalTrials.gov number, NCT00004205.)
Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Inhibidores de la Aromatasa/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Nitrilos/administración & dosificación , Tamoxifeno/administración & dosificación , Triazoles/administración & dosificación , Antineoplásicos Hormonales/efectos adversos , Inhibidores de la Aromatasa/efectos adversos , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Método Doble Ciego , Esquema de Medicación , Femenino , Estudios de Seguimiento , Fracturas Óseas/epidemiología , Humanos , Incidencia , Estimación de Kaplan-Meier , Letrozol , Recurrencia Local de Neoplasia/prevención & control , Nitrilos/efectos adversos , Posmenopausia , Modelos de Riesgos Proporcionales , Tamoxifeno/efectos adversos , Triazoles/efectos adversosRESUMEN
Weight gain is commonly reported by breast cancer patients on tamoxifen or aromatase inhibitors. Since weight gain may impact on outcome and compliance we have prospectively assessed the effects of these agents on weight change in three randomised trials for the treatment or prevention of breast cancer. Data on weight change in postmenopausal women from three large clinical trials investigating endocrine therapy for the treatment or prevention of breast cancer were analysed (ATAC, IBIS-I and IBIS-II). In the IBIS-I study, mean weight change on tamoxifen was +0.1 kg (SD 0.1) compared with +0.3 kg (SD 0.1) in women taking the placebo (P = 0.3) between baseline and 12 months of follow-up. In the IBIS-II trial, no statistically significant difference was found between anastrozole and placebo after 12 months of follow-up [+0.8 kg (SD 5.3) vs. +0.5 kg (SD 7.4), P = 0.5]. In the ATAC trial, no statistically significant differences in weight gain between anastrozole and tamoxifen were found after 12 months of follow-up [+1.4 kg (SD 3.9) vs. +1.5 kg (SD 4.0), P = 0.4]. Significant baseline predictors for gaining more than 5 kg of weight after 12 months of follow-up were: being younger than 60 years old, smoking and mastectomy. All three trials demonstrate that weight gain occurs primarily within the first 12 months of active treatment in a subset of patients. In the prevention trials, weight gain does not differ between anastrozole, tamoxifen and placebo and also did not differ between anastrozole and tamoxifen in the treatment trial.
Asunto(s)
Antineoplásicos Hormonales/efectos adversos , Neoplasias de la Mama/prevención & control , Neoplasias Hormono-Dependientes/prevención & control , Nitrilos/efectos adversos , Tamoxifeno/efectos adversos , Triazoles/efectos adversos , Aumento de Peso/efectos de los fármacos , Anciano , Anastrozol , Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Nitrilos/uso terapéutico , Posmenopausia , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Factores de Riesgo , Tamoxifeno/uso terapéutico , Triazoles/uso terapéuticoRESUMEN
Data reviewed at the Kyoto Breast Cancer Consensus Conference (KBCCC) showed that preoperative systemic therapy (PST) could optimize surgery through the utilization of information relating to pre- and post-PST tumor stage, therapeutic sensitivity, and treatment-induced changes in the biological characteristics of the tumor. As such, it was noted that the biological characteristics of the tumor, such as hormone receptors, human epidermal growth factor receptor-2, histological grade, cell proliferative activity, mainly defined by the Ki67 labeling index, and the tumor's multi-gene signature, should be considered in the planning of both systemic and local therapy. Furthermore, the timing of axillary sentinel lymph node diagnosis (i.e., before or after the PST) was also noted to be critical in that it may influence the likelihood of axillary preservation, even in node positive cases. In addition, axillary diagnosis with ultrasound and concomitant fine needle aspiration cytology or core needle biopsy (CNB) was reported to contribute to the construction of a treatment algorithm for patient-specific or individualized axillary surgery. Following PST, planning for breast surgery should therefore be based on tumor subtype, tumor volume and extent, therapeutic response to PST, and patient preference. Nomograms for predicting nodal status and drug sensitivity were also recognized as a tool to support decision-making in the selection of surgical treatment. Overall, review of data at the KBCCC showed that PST increases the likelihood of patients receiving localized surgery and individualized treatment regimens.
Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/terapia , Cuidados Preoperatorios , Algoritmos , Axila/cirugía , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Metástasis Linfática/patología , Terapia Neoadyuvante , Nomogramas , Biopsia del Ganglio Linfático Centinela , Carga TumoralRESUMEN
In March, 2010, a group of breast cancer experts met to develop a consensus statement on breast cancer prevention, with a focus on medical and therapeutic interventions. We present the conclusions in this Review. First we agreed that the term chemoprevention is inappropriate and suggested that the term preventive therapy better represents this feature of management. Two selective oestrogen-receptor modulators--tamoxifen and raloxifene--are so far the only medical options approved by the US Food and Drug Administration for preventive therapy. Of these tamoxifen has greater efficacy and can be used in premenopausal women, but raloxifene has fewer side-effects. Two newer drugs in this class, lasofoxifene and arzoxifene, also show efficacy and possibly a better overall risk-benefit profile, but need further assessment. Aromatase inhibitors might be more efficacious, and results of prevention trials are eagerly awaited. Newer agents, notably bisphosphonates and metformin, have shown promise in observational studies and need to be assessed in randomised prevention trials. Other agents, such as aspirin, other non-steroidal anti-inflammatory drugs, COX-2 inhibitors, retinoids, rexinoids, and dietary components have limited effects or are in the early phases of investigation. New contralateral tumours in women with breast cancer might be generally useful as a model for prevention, as has been seen for tamoxifen. If valid such a model would facilitate the design of simpler, cheaper, and better-focused trials for assessing new agents.