Relationship between IHC4 score and response to neo-adjuvant chemotherapy in estrogen receptor-positive breast cancer.

AIMS: To determine whether IHC4 score assessed on pre-treatment core biopsies (i) predicts response to neo-adjuvant chemotherapy in ER-positive (ER+) breast cancer; (ii) provides more predictive information than Ki67 alone. METHODS: 113 patients with ER+ primary breast cancer treated with neo-adjuvant chemotherapy at the Royal Marsden Hospital between 2002 and 2010 were included in the study. Pathologic assessment of the excision specimen was made for residual disease. IHC4 was determined on pre-treatment core biopsies, blinded to clinical outcome, by immunohistochemistry using quantitative scoring of ER (H-score), PgR (%) and Ki67 (%). Determination of HER2 status was made by immunohistochemistry and fluorescent in situ hybridization for 2+ cases. IHC4 and Ki67 scores were tested for their association with pathological complete response (pCR) rate and residual cancer burden (RCB) score. RESULTS: 18 (16%) of the 113 patients and 8 (9%) of the 88 HER2-ve cases achieved pCR. Ki67 and IHC4 score were both positively associated with achievement of pCR (P < 10-7 and P < 10-9, respectively) and RCB0+1 (P < 10-5 and P < 10-9, respectively) following neo-adjuvant chemotherapy in all patients. Rates of pCR+RCB1 were 45 and 66% in the highest quartiles of Ki67 and IHC4 scores, respectively. In ER+HER2-ve cases, pCR+RCB1 rates were 35% and in the highest quartile of both Ki67 and IHC4. There were no pCRs in the lower half of IHC4 or Ki67 scores. CONCLUSIONS: IHC4 was strongly predictive of pCR or near pCR in ER+ breast cancers following neo-adjuvant chemotherapy. Ki67 was an important component of this predictive ability, but was not as predictive as IHC4.

Case report: A rare case of eosinophilic cholecystitis presenting after talc pleurodesis for recurrent pneumothorax.

Eosinophilic cholecystitis (EC) is a rare inflammatory condition of the gallbladder, confirmed by a cellular infiltrate comprised of more than 90% eosinophils in the gallbladder wall on histological examination. Although the etiology of EC is largely unknown, local autoimmune reactions within the gallbladder wall to inflammatory mediators from distal sites of inflammation have been hypothesized. Talc pleurodesis (TP) is a common clinical procedure used within respiratory medicine. However, it is associated with activation of systemic acute inflammatory responses including an increase in serum interleukin-8 (IL-8), which is a potent mediator of eosinophil chemotaxis. We report a case of EC following a TP procedure for persistent, secondary pneumothorax.

Clinical utility of the IHC4+C score in oestrogen receptor-positive early breast cancer: a prospective decision impact study.

BACKGROUND: Most oestrogen receptor (ER)-positive early breast cancer diagnosed today is highly curable with multimodality treatment. Systemic adjuvant treatments including endocrine therapy and chemotherapy have made a significant contribution to the increasing cure rates over the past three decades. However not all women will require chemotherapy. The IHC4+C score is a prognostic tool that integrates four immunohistochemical measures with clinicopathological features to estimate the residual risk of distant recurrence at 10 years in post-menopausal women with ER-positive breast cancer who have received 5 years of endocrine therapy. Retrospective studies indicate that the test can identify a set of women that are at such low risk of recurrence that chemotherapy can be of little benefit. METHODS: In this study, 124 patients were prospectively selected from the multidisciplinary team meeting between January 2013 and April 2014 for IHC4+C testing. Adjuvant systemic treatment recommendations by clinicians were recorded without and with the availability of the score in addition to the patient's decision. RESULTS: There was concordance in the MDT's recommendation without and with the availability of the score in 73% of cases. Clinicians recommended chemotherapy or at least its discussion to 74 (59%) patients, which fell to 32 (34%) patients after the IHC4+C score was made available, sparing one in four tested patients a chemotherapy recommendation, along with its toxicity and expense. CONCLUSION: This decision impact study shows that when used by clinicians in the multidisciplinary team meeting for adjuvant decision-making, a significant proportion of patients are spared chemotherapy recommendations.

Residual proliferative cancer burden to predict long-term outcome following neoadjuvant chemotherapy.

BACKGROUND: The purpose of this study was (i) to test the hypothesis that combining Ki67 with residual cancer burden (RCB) following neoadjuvant chemotherapy, as the residual proliferative cancer burden (RPCB), provides significantly more prognostic information than either alone; (ii) to determine whether also integrating information on ER and grade improves prognostic power. PATIENTS AND METHODS: A total of 220 patients treated with neoadjuvant chemotherapy for primary breast cancer were included in the study. Analyses employed a Cox proportional hazard model. Prognostic indices (PIs) were created adding in Ki67, grade and ER to RCB. Leave-one-out cross-validation was used to reduce bias. The overall change in χ(2) of the best model for each index was used to compare the prognostic ability of the different indices. RESULTS: All PIs provided significant prognostic information for patients with residual disease following neoadjuvant chemotherapy. RPCB (χ(2) = 61.4) was significantly more prognostic than either RCB (χ(2) = 38.1) or Ki67 (χ(2) = 53.8) alone P < 0.001. A PI incorporating RCB, Ki67 grade and ER provided the most prognostic information overall and gave χ(2) = 73.8. CONCLUSIONS: This study provides proof of principle that the addition of post-treatment Ki67 to RCB improves the prediction of long-term outcome. Prediction may be further improved by addition of post-treatment grade and ER and warrants further investigation for estimating post-neoadjuvant risk of recurrence. These indices may have utility in stratifying patients for novel therapeutic interventions after neoadjuvant chemotherapy.

Biomarker changes associated with the development of resistance to aromatase inhibitors (AIs) in estrogen receptor-positive breast cancer.

BACKGROUND: The purpose of this study was to identify any differences in key biomarkers associated with estrogen action between biopsies taken at diagnosis and at recurrence or progression during treatment with an aromatase inhibitor (AI). PATIENTS AND METHODS: Patients were retrospectively identified from a clinical database as having relapsed or progressed during AI treatment. Immunohistochemistry was carried out against estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), insulin-like growth factor type-1 receptor (IGF1R), insulin receptor substrate-1 (IRS-1), stathmin, phosphatase and tensin homolog and Ki67. RESULTS: Fifty-five pairs of samples were identified with ER- and/or PgR-positive diseases. Four (7%) patients were ER-negative at progression. Overall, PgR levels were lower in the recurrence sample, but 35% of cases remained positive. IGF1R levels decreased significantly. There were no substantial changes in HER2, IRS-1 or stathmin levels to indicate a role in resistance. Higher Ki67 levels at resistance indicate more proliferative disease. CONCLUSIONS: The phenotype of AI-recurrent lesions shows high between-tumour heterogeneity. There is evidence of an increase in Ki67, a reduction in IGF1R and a loss of ER expression in some individuals and some activation of growth factor signalling pathways that may explain resistance in individuals and merit treatment targeted to those pathways. Biopsy at recurrence will be necessary to identify the relevant target for individuals.

Assessment of the contribution of the IHC4+C score to decision making in clinical practice in early breast cancer.

BACKGROUND: The immunohistochemical (IHC) 4+C score is a cost-effective prognostic tool that uses clinicopathologic factors and four standard IHC assays: oestrogen receptor (ER), PR, HER2 and Ki67. We assessed its utility in personalising breast cancer treatment in a clinical practice setting, through comparison with Adjuvant! Online (AoL) and the Nottingham Prognostic Index (NPI). METHODS: We prospectively gathered clinicopathologic data for postmenopausal patients with hormone receptor-positive, HER2-negative, N0-3 resected early breast cancer treated consecutively at our institution. We retrospectively calculated and compared prognostic scores. The primary endpoint was the proportion of patients reclassified from AoL-defined intermediate-risk by application of the IHC4+C score. RESULTS: The median age of the 101 patients included in the analysis was 63. In all, 15 of the 26 patients classified as intermediate-risk by AoL were reallocated to a low-risk group by application of the IHC4+C score and no patient was reclassified as high-risk group. Of the 59 patients classified as intermediate-risk group by the NPI, 24 were reallocated to a low-risk group and 13 to a high-risk group. CONCLUSION: IHC4+C reclassifies more than half of the patients stratified as being in intermediate-risk group by the AoL and NPI. The use of IHC4+C may substantially improve decision-making on adjuvant chemotherapy.

Relationship between estrogen receptor, progesterone receptor, HER-2 and Ki67 expression and efficacy of aromatase inhibitors in advanced breast cancer.

BACKGROUND: Surprisingly few data are published on the relevance of even commonly used biomarkers of response to aromatase inhibitors (AIs) in advanced breast cancer. Here, we aim to determine the effectiveness of AIs in that setting according to quantitative levels of estrogen receptor (ER), progesterone receptor (PgR) and Ki67 or human epithelial growth factor receptor-2 (HER-2) status. PATIENTS AND METHODS: ER, PgR, HER-2 and Ki67 protein expressions were centrally assessed in 177 archival formalin-fixed paraffin-embedded primary or locally recurrent breast tumours from women who subsequently received AI treatment of advanced disease. RESULTS: Among ER-positive patients (n = 146), higher PgR, but not ER, levels were associated with increased time to AI treatment failure (TTF). Higher Ki67 staining was associated with decreased TTF. ER-positive/HER-2-positive patients showed a non-significant trend for decreased TTF compared with ER-positive/HER-2-negative patients. PgR level, but not Ki67, remained a significant predictor of TTF in multivariate analysis of ER-positive patients. CONCLUSIONS: Higher PgR and Ki67 levels are significantly associated with increased and decreased TTF, respectively, in ER-positive patients receiving AI treatment of advanced disease. The higher proliferation seen in PgR-negative tumours does not explain the poorer clinical responsiveness of this subgroup.

A spiritually-based measure of holistic health for those with disabilities: development, preliminary reliability and validity assessment.

PURPOSE: To develop and test a spiritually-based measure of holistic health for those with chronic physical conditions. METHOD: Two studies are reported. Study One used 69 ex-patients with chronic physical conditions to develop a spiritually-based holistic measure of health. An open-ended questionnaire, the Participant Health Questionnaire used the echo technique to obtain statements about the nature of health. These were assembled to form the Rating of Health Statements Questionnaire, which was completed by 59 participants. Reliability and validity analysis yielded a 38-item Health Attitude Scale, the HAS:1, to which the responses of 48 participants produced the 40-item HAS:2, which included an Intent subscale. Wording the HAS:2 in the past tense then created a behavioural measure, the QE Health Scale (QEHS). Study Two used 233 participants from the same population with chronic conditions to assess the reliability of the HAS:2 and QEHS, and their validity against the STAI and the SOC-13. RESULTS: The QEHS proved reliable (Cronbach's alpha = 0.92) and valid in that it correlated with the SOC-13 (r = 0.32, p < 0.01), the STAI (State) (r = 0. - 39, p < 0.01), the STAI (Trait) (r = 0.35, p < 0.01), the HAS:2 (Importance) (r = 0.61, p < 0.01) and the HAS:2 (Intent) (r = 0.61, p < 0.01). CONCLUSION: The QEHS possessed sufficient reliability and validity as a spiritually-based holistic measure of health to warrant further investigation.

The QE Health Scale (QEHS): assessment of the clinical reliability and validity of a spiritually based holistic health measure.

PURPOSE: To assess the clinical reliability and validity of a holistic health measure, the QE Health Scale (QEHS), for use with people with physical disabilities. METHOD: A test-retest design saw the QEHS administered and compared with established measures of health at admission and discharge from three-week inpatient rehabilitation programmes. Data was analysed by factor and correlation analysis. Clinician-reported credibility and usefulness of the theoretical basis of the QEHS, the QEHS itself, and Patient Profiles derived from the QEHS were also used to evaluate clinical validity. RESULTS: The QEHS was judged to possess satisfactory reliability and validity. CONCLUSION: The QEHS is a clinically reliable, valid, credible and useful holistic health instrument to facilitate client-centred therapeutic interventions, inform decision-making and evaluate outcomes for people with physical disabilities.

Microarray-based comparative genomic hybridisation of breast cancer patients receiving neoadjuvant chemotherapy.

We analysed the molecular genetic profiles of breast cancer samples before and after neoadjuvant chemotherapy with combination doxorubicin and cyclophosphamide (AC). DNA was obtained from microdissected frozen breast core biopsies from 44 patients before chemotherapy. Additional samples were obtained before the second course of chemotherapy (D21) and after the completion of the treatment (surgical specimens) in 17 and 21 patients, respectively. Microarray-based comparative genome hybridisation was performed using a platform containing approximately 5800 bacterial artificial chromosome clones (genome-wide resolution: 0.9 Mb). Analysis of the 44 pretreatment biopsies revealed that losses of 4p, 4q, 5q, 12q13.11-12q13.12, 17p11.2 and 17q11.2; and gains of 1p, 2p, 7q, 9p, 11q, 19p and 19q were significantly associated with oestrogen receptor negativity. 16q21-q22.1 losses were associated with lobular and 8q24 gains with ductal types. Losses of 5q33.3-q4 and 18p11.31 and gains of 6p25.1-p25.2 and Xp11.4 were associated with HER2 amplification. No correlations between DNA copy number changes and clinical response to AC were found. Microarray-based comparative genome hybridisation analysis of matched pretreatment and D21 biopsies failed to identify statistically significant differences, whereas a comparison between matched pretreatment and surgical samples revealed a statistically significant acquired copy number gain on 11p15.2-11p15.5. The modest chemotherapy-driven genomic changes, despite profound loss of cell numbers, suggest that there is little therapeutic selection of resistant non-modal cell lineages.

The role of the spiritual dimension of the self as the prime determinant of health.

PURPOSE: To present a clinical commentary on the relationship of spirituality to healthcare for those with chronic physical conditions. METHOD: A spiritually based theory of self-identity was presented, based on selected literature to identify the process of health attainment for those with chronic conditions. The resultant Health Change Process Theory was then discussed in relation to relevant empirical research and the implications for rehabilitation practice were outlined. RESULTS: The development of a resilient, intrinsic, spiritually based concept of self was found to be pivotal to health outcomes in rehabilitation. This was then incorporated within a Health Change Process Theory to explain and predict the course followed by people with chronic disorders to achieve health. CONCLUSION: The Health Change Process Theory provides an inclusive framework within which acute and chronic rehabilitation healthcare can be merged to maximise health outcomes. Nevertheless, a need remains to develop a quantitative measure of individual holistic health, based on this theory, to facilitate its use in rehabilitation practice. This paper forwards an explanation for the process that people experiencing chronic physical disabilities undergo as they achieve health. A concept of self that identifies the spiritual core as the component that determines the constancy and continuity of self as a whole which is necessary for health is presented as the basis of the rehabilitative health process.

Growth factor signalling and response to endocrine therapy: the Royal Marsden Experience.

De novo resistance to endocrine therapy is a near-universal feature of oestrogen receptor (ER)- negative breast cancer. Although many ER-positive breast cancers also show no response to tamoxifen or aromatase inhibitors on objective clinical grounds the large majority show reduced proliferation indicating that some oestrogen dependence is present in almost all ER-positive breast cancer. In neoadjuvant studies HER2 positivity is associated with poor response rates to tamoxifen but not aromatase inhibitors, consistent with preclinical models. Acquired resistance to tamoxifen is associated with decreases in ER positivity but most recurrent lesions remain ER-positive. A small proportion of these show increased HER2 expression and in these patients increased phospho-p38 may contribute to the tamoxifen-resistant phenotype. There is an unfortunate paucity of clinical and biological data on acquired resistance to aromatase inhibitors.

Anastrozole demonstrates clinical and biological effectiveness in oestrogen receptor-positive breast cancers, irrespective of the erbB2 status.

Overexpression of erbB2 in breast tumours can predict resistance to tamoxifen therapy. We conducted a small trial to determine if erbB2 status correlates with tumour response and biochemical changes in postmenopausal women receiving neoadjuvant therapy with the aromatase inhibitor, anastrozole. Twenty-four postmenopausal women with oestrogen receptor (ER)-rich, large, operable breast tumours received three months of neoadjuvant anastrozole, 1 or 10 mg daily, then surgery, followed by another five years of anastrozole 1 mg daily. Response to the treatment was based on changes in clinical and ultrasound measurements of tumour volume and changes in tumour proliferation and progesterone receptor (PgR) status. After follow-up for a median duration of four years therapy, there was no apparent difference between erbB2 0/1+ and erbB2 3+ tumours in clinical response or changes in proliferation and PgR expression. In conclusion, anastrozole appears to be an effective endocrine option in this patient population, irrespective of the erbB2 status.

High incidence of HER-2 positivity in inflammatory breast cancer.

HER-2 is over-expressed in around 25% of human breast cancers, and is associated with poor outcome. We examined the incidence of HER-2 status in inflammatory breast cancer (IBC). Forty-nine newly diagnosed IBCs were studied. Formalin-fixed paraffin-embedded pre-treatment tissue biopsies were examined immunohistochemically for the over-expression of the HER-2 protein and gene using the HercepTest and FISH assay. Clinical outcome was compared between the HER-2 positive (HercepTest score 3 + and FISH positive) and negative groups. Fifty-two per cent of the IBCs examined were HER-2 positive. The HER-2 positive group were demographically comparable to the HER-2 negative group. Ninety-six per cent of the HER-2 positive patients responded to primary chemotherapy compared to 76% of the HER-2 negative (P = 0.09). No significant differences in outcome emerged between the two groups. In conclusion, this study found the incidence of HER-2 protein over-expression in IBC is higher than previously reported in non-IBC. Early HER-2 directed therapy (such as the monoclonal antibody trastuzumab) as a part of multimodal treatment may improve outcome in this poor prognosis cancer.

Investigation of health perspectives of those with physical disabilities: the role of spirituality as a determinant of health.

PURPOSE: To identify key determinants of health and the process of health attainment for people with musculoskeletal disabilities. METHOD: Focus groups of people with musculoskeletal disorders, including 30 members and their five trained facilitators, provided data. Discussed were 'What is health for you?' and 'What has helped, or would help you achieve this health?' Delphi-structured analysis identified health themes and a health process model was developed with the facilitators comprising the expert panel. RESULTS: Health was perceived as centred on relationships that required a spiritual awareness for a strong and resilient identity. The Self Attributes Model developed portrays the processes perceived to be required for health. CONCLUSIONS: Although physical, social and psychological interventions are essential aspects of health intervention, by themselves they are not sufficient. Also required for health is a strong resilient self resulting from interaction and connection with other people and the natural world. Moreover, development of such an identity requires a spiritual world-view comprising an acknowledgement of the essence of self and focus upon the nature of the connection of this essence with all other aspects of life. Further research is required to advance understanding of the process by which this occurs for people with chronic disorders.

Correlation between immunohistochemistry (HercepTest) and fluorescence in situ hybridization (FISH) for HER-2 in 426 breast carcinomas from 37 centres.

Accurate diagnostic assessment of HER-2 is essential for the appropriate application of the humanized anti-HER-2 monoclonal antibody trastuzumab (Herceptin) to the treatment of patients with metastatic breast cancer. The diagnostic test needs to be applicable to archival, fixed tissue removed at excision, in many cases several years earlier. We compared the assessment of HER-2 by immunohistochemistry (IHC; HercepTest) and fluorescence in situ hybridization (FISH) in 426 breast carcinomas from patients being considered for trastuzumab therapy. The tumours were tested in three reference centres having been sent in from 37 hospitals. Only 2/270 (0.7%) IHC 0/1+ tumours were FISH positive. Six of 102 (5.9%) IHC 3+ tumours were FISH negative. Five of the six had between 1.75 and 2.0 HER-2 gene copies per chromosome 17 and the sixth had multiple copies of chromosome 17. Thirteen per cent of tumours were IHC 2+ and overall 48% of these were FISH positive but this proportion varied markedly between the centres. Sixty IHC-stained slides selected to be enriched with 2+ cases were circulated between the three laboratories and scored. There were 20 cases in which there was some discordance in scoring. Consideration of the FISH score in these cases led to concordance in the designation of positivity/negativity in 19 of these 20 cases. These data support an algorithm in which FISH testing is restricted to IHC 2+ tumours in reference centres. The results may not extrapolate to laboratories with less experience or using different methodologies.

Watching the Games: public health surveillance for the Sydney 2000 Olympic Games.

STUDY OBJECTIVE: To describe the development of the public health surveillance system for the Sydney 2000 Olympic Games; document its major findings; and discuss the implications for public health surveillance for future events. DESIGN: Planning for the system took almost three years. Its major components included increased surveillance of communicable diseases; presentations to sentinel emergency departments; medical encounters at Olympic venues; cruise ship surveillance; environmental and food safety inspections; surveillance for bioterrorism; and global epidemic intelligence. A daily report integrated data from all sources. SETTING: Sydney, Australia. Surveillance spanned the period 28 August to 4 October 2000. PARTICIPANTS: Residents of Sydney, athletes and officials, Australian and international visitors. MAIN RESULTS: No outbreaks of communicable diseases were detected. There were around 5% more presentations to Sydney emergency departments than in comparable periods in other years. Several incidents detected through surveillance, including injuries caused by broken glass, and a cluster of presentations related to the use of the drug ecstasy, prompted further action. CONCLUSIONS: Key elements in the success of public health surveillance for the Games included its careful planning, its comprehensive coverage of public health issues, and its timely reporting and communication processes. Future systems need to be flexible enough to detect the unexpected.

HER-2 amplification impedes the antiproliferative effects of hormone therapy in estrogen receptor-positive primary breast cancer.

In experimental models, human epidermal growth factor receptor-2 (HER-2) amplification leads to estrogen independence and tamoxifen resistance in estrogen receptor (ER)-positive human breast cancer cells. Some but not all reports suggest an association between HER-2 positivity and hormone independence in breast cancer patients. This study aimed to evaluate the antiproliferative effects of endocrine therapy in HER-2-positive/ER-positive primary human breast cancer. The effect on proliferation (Ki67) of hormone therapy was assessed at 2 weeks and/or 12 weeks in biopsies from 115 primary breast cancers with ER-positive tumors. The patients took part in one of 3 neoadjuvant trials of hormonal therapy with a SERM (tamoxifen or idoxifene) or an aromatase inhibitor (anastrozole or vorozole). HER-2 status was assessed by immunocytochemistry and fluorescence in situ hybridization (FISH). Fifteen patients were defined as HER-2 positive by both immunohistochemistry and FISH, with the remaining 100 patients HER-2 negative. Geometric mean Ki67 levels were substantially higher in HER-2-positive than HER-2-negative tumors (27.7% versus 11.5%, respectively; P = 0.003). In HER-2-negative patients, Ki67 was reduced by 62 and 71% at 2 and 12 weeks, respectively (P < 0.0001 for both), but HER-2-positive patients showed no significant fall. The proportional change in Ki67 was significantly different between HER-2-positive and -negative patients (P = 0.014 at 2 weeks; P = 0.047 at 12 weeks). Mean ER levels were lower in the HER-2-positive patients (P = 0.06) but the change in Ki67 was impeded even in those with high ER. Apoptotic index was reduced by 30% at 2 weeks in the HER-2-negative group. However, there were no statistically significant differences in apoptotic index between the groups. It is concluded that ER-positive/HER-2-positive primary breast carcinomas show an impeded antiproliferative response to endocrine therapy that nonetheless may vary between individual treatments. This together with high baseline proliferation is likely to translate to poor clinical response.

Effect of raloxifene on breast cancer cell Ki67 and apoptosis: a double-blind, placebo-controlled, randomized clinical trial in postmenopausal patients.

PURPOSE: Raloxifene is a selective estrogen receptor (ER) modulator approved for prevention and treatment of postmenopausal osteoporosis. This is an exploratory study of raloxifene in primary breast cancer patients. EXPERIMENTAL DESIGN: Postmenopausal women (50-80 years of age), with histological or cytological diagnosis of stage I or II primary breast cancer, were randomly assigned to 14 days of placebo, 60 mg/day raloxifene, or 300 mg twice daily (600 mg/day) of raloxifene. A core biopsy of the primary tumor was obtained before therapy, and a representative sample of the excised tumor was obtained from the operative specimen after treatment. Paired baseline and endpoint biopsies from each patient were analyzed for Ki67, apoptosis, and estrogen and progesterone receptors. Treatment group differences in efficacy measurements were primarily evaluated for baseline-to-endpoint change and percentage change using a one-way ANOVA with treatment as the fixed effect. RESULTS: Of 167 enrolled patients, 143 had evaluable efficacy data. Most breast cancer cases were invasive (98.6%), stage I (76.6%), and ER-positive (83.2%). In patients with ER-positive tumors, Ki67 increased 7% from baseline on placebo and decreased by 21% on 60 mg/day raloxifene (P = 0.015 versus placebo) and by 14% on 600 mg/day raloxifene (P = 0.064 versus placebo). Raloxifene did not affect apoptosis. ER decreased significantly with 60 mg/day or 600 mg/day raloxifene compared with placebo (P < 0.01 for each comparison). Raloxifene had no statistically significant effects on Ki67 among patients with ER-negative tumors. There were no treatment differences in adverse events. CONCLUSION: In this exploratory trial, 60 mg/day raloxifene showed a significant antiproliferative effect in ER-positive breast cancer, demonstrated by the decrease in Ki67, with no effect in ER-negative cancer. This provides support for raloxifene having a breast cancer preventive effect in postmenopausal women.