Showing papers on "Breast cancer published in 2003"

Prospective identification of tumorigenic breast cancer cells

Abstract: Breast cancer is the most common malignancy in United States women, accounting for >40,000 deaths each year. These breast tumors are comprised of phenotypically diverse populations of breast cancer cells. Using a model in which human breast cancer cells were grown in immunocompromised mice, we found that only a minority of breast cancer cells had the ability to form new tumors. We were able to distinguish the tumorigenic (tumor initiating) from the nontumorigenic cancer cells based on cell surface marker expression. We prospectively identified and isolated the tumorigenic cells as CD44+CD24−/lowLineage− in eight of nine patients. As few as 100 cells with this phenotype were able to form tumors in mice, whereas tens of thousands of cells with alternate phenotypes failed to form tumors. The tumorigenic subpopulation could be serially passaged: each time cells within this population generated new tumors containing additional CD44+CD24−/lowLineage− tumorigenic cells as well as the phenotypically diverse mixed populations of nontumorigenic cells present in the initial tumor. The ability to prospectively identify tumorigenic cancer cells will facilitate the elucidation of pathways that regulate their growth and survival. Furthermore, because these cells drive tumor development, strategies designed to target this population may lead to more effective therapies.

Repeated observation of breast tumor subtypes in independent gene expression data sets

Abstract: Characteristic patterns of gene expression measured by DNA microarrays have been used to classify tumors into clinically relevant subgroups. In this study, we have refined the previously defined subtypes of breast tumors that could be distinguished by their distinct patterns of gene expression. A total of 115 malignant breast tumors were analyzed by hierarchical clustering based on patterns of expression of 534 "intrinsic" genes and shown to subdivide into one basal-like, one ERBB2-overexpressing, two luminal-like, and one normal breast tissue-like subgroup. The genes used for classification were selected based on their similar expression levels between pairs of consecutive samples taken from the same tumor separated by 15 weeks of neoadjuvant treatment. Similar cluster analyses of two published, independent data sets representing different patient cohorts from different laboratories, uncovered some of the same breast cancer subtypes. In the one data set that included information on time to development of distant metastasis, subtypes were associated with significant differences in this clinical feature. By including a group of tumors from BRCA1 carriers in the analysis, we found that this genotype predisposes to the basal tumor subtype. Our results strongly support the idea that many of these breast tumor subtypes represent biologically distinct disease entities.

Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case series unselected for family history: a combined analysis of 22 studies

Abstract: Germline mutations in BRCA1 and BRCA2 confer high risks of breast and ovarian cancer, but the average magnitude of these risks is uncertain and may depend on the context. Estimates based on multiple-case families may be enriched for mutations of higher risk and/or other familial risk factors, whereas risk estimates from studies based on cases unselected for family history have been imprecise. We pooled pedigree data from 22 studies involving 8,139 index case patients unselected for family history with female (86%) or male (2%) breast cancer or epithelial ovarian cancer (12%), 500 of whom had been found to carry a germline mutation in BRCA1 or BRCA2. Breast and ovarian cancer incidence rates for mutation carriers were estimated using a modified segregation analysis, based on the occurrence of these cancers in the relatives of mutation-carrying index case patients. The average cumulative risks in BRCA1-mutation carriers by age 70 years were 65% (95% confidence interval 44%-78%) for breast cancer and 39% (18%-54%) for ovarian cancer. The corresponding estimates for BRCA2 were 45% (31%-56%) and 11% (2.4%-19%). Relative risks of breast cancer declined significantly with age for BRCA1-mutation carriers (P trend.0012) but not for BRCA2-mutation carriers. Risks in carriers were higher when based on index breast cancer cases diagnosed at <35 years of age. We found some evidence for a reduction in risk in women from earlier birth cohorts and for variation in risk by mutation position for both genes. The pattern of cancer risks was similar to those found in multiple-case families, but their absolute magnitudes were lower, particularly for BRCA2. The variation in risk by age at diagnosis of index case is consistent with the effects of other genes modifying cancer risk in carriers.

Breast and ovarian cancer risks due to inherited mutations in BRCA1 and BRCA2.

Abstract: Risks of breast and ovarian cancer were determined for Ashkenazi Jewish women with inherited mutations in the tumor suppressor genes BRCA1 and BRCA2. We selected 1008 index cases, regardless of family history of cancer, and carried out molecular analysis across entire families. The lifetime risk of breast cancer among female mutation carriers was 82%, similar to risks in families with many cases. Risks appear to be increasing with time: Breast cancer risk by age 50 among mutation carriers born before 1940 was 24%, but among those born after 1940 it was 67%. Lifetime risks of ovarian cancer were 54% for BRCA1 and 23% for BRCA2 mutation carriers. Physical exercise and lack of obesity in adolescence were associated with significantly delayed breast cancer onset.

A randomized comparison of sentinel-node biopsy with routine axillary dissection in breast cancer.

Abstract: Background Although numerous studies have shown that the status of the sentinel node is an accurate predictor of the status of the axillary nodes in breast cancer, the efficacy and safety of sentinel-node biopsy require validation. Methods From March 1998 to December 1999, we randomly assigned 516 patients with primary breast cancer in whom the tumor was less than or equal to 2 cm in diameter either to sentinel-node biopsy and total axillary dissection (the axillary-dissection group) or to sentinel-node biopsy followed by axillary dissection only if the sentinel node contained metastases (the sentinel-node group). Results The number of sentinel nodes found was the same in the two groups. A sentinel node was positive in 83 of the 257 patients in the axillary-dissection group (32.3 percent), and in 92 of the 259 patients in the sentinel-node group (35.5 percent). In the axillary-dissection group, the overall accuracy of the sentinel-node status was 96.9 percent, the sensitivity 91.2 percent, and the specifi...

Influence of Estrogen Plus Progestin on Breast Cancer and Mammography in Healthy Postmenopausal Women: The Women's Health Initiative Randomized Trial

Abstract: ContextThe Women's Health Initiative trial of combined estrogen plus progestin was stopped early when overall health risks, including invasive breast cancer, exceeded benefits. Outstanding 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.ObjectiveTo determine the relationship among estrogen plus progestin use, breast cancer characteristics, and mammography recommendations.Design, Setting, and ParticipantsFollowing a comprehensive breast cancer risk assessment, 16 608 postmenopausal women aged 50 to 79 years with an intact uterus were randomly 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 MeasuresBreast cancer number and characteristics, and frequency of abnormal mammograms by estrogen plus progestin exposure.ResultsIn 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.ConclusionsRelatively 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.

EZH2 is a marker of aggressive breast cancer and promotes neoplastic transformation of breast epithelial cells

Abstract: The Polycomb Group Protein EZH2 is a transcriptional repressor involved in controlling cellular memory and has been linked to aggressive prostate cancer. Here we investigate the functional role of EZH2 in cancer cell invasion and breast cancer progression. EZH2 transcript and protein were consistently elevated in invasive breast carcinoma compared with normal breast epithelia. Tissue microarray analysis, which included 917 samples from 280 patients, demonstrated that EZH2 protein levels were strongly associated with breast cancer aggressiveness. Overexpression of EZH2 in immortalized human mammary epithelial cell lines promotes anchorage-independent growth and cell invasion. EZH2-mediated cell invasion required an intact SET domain and histone deacetylase activity. This study provides compelling evidence for a functional link between dysregulated cellular memory, transcriptional repression, and neoplastic transformation.

A Randomized Trial of Letrozole in Postmenopausal Women after Five Years of Tamoxifen Therapy for Early-Stage Breast Cancer

Abstract: background In hormone-dependent breast cancer, five years of postoperative tamoxifen therapy — but not tamoxifen therapy of longer duration — prolongs disease-free and overall survival. The aromatase inhibitor letrozole, by suppressing estrogen production, might improve the outcome after the discontinuation of tamoxifen therapy. methods We conducted a double-blind, placebo-controlled trial to test the effectiveness of five years of letrozole therapy in postmenopausal women with breast cancer who have completed five years of tamoxifen therapy. The primary end point was disease-free survival. results A total of 5187 women were enrolled (median follow-up, 2.4 years). At the first interim analysis, there were 207 local or metastatic recurrences of breast cancer or new primary cancers in the contralateral breast — 75 in the letrozole group and 132 in the placebo group — with estimated four-year disease-free survival rates of 93 percent and 87 percent, respectively, in the two groups (P ≤ 0.001 for the comparison of disease-free survival). A total of 42 women in the placebo group and 31 women in the letrozole group died (P=0.25 for the comparison of overall survival). Low-grade hot flashes, arthritis, arthralgia, and myalgia were more frequent in the letrozole group, but vaginal bleeding was less frequent. There were new diagnoses of osteoporosis in 5.8 percent of the women in the letrozole group and 4.5 percent of the women in the placebo group (P=0.07); the rates of fracture were similar. After the first interim analysis, the independent data and safety monitoring committee recommended termination of the trial and prompt communication of the results to the participants. conclusions As compared with placebo, letrozole therapy after the completion of standard tamoxifen treatment significantly improves disease-free survival.

Improved Outcomes From Adding Sequential Paclitaxel but Not From Escalating Doxorubicin Dose in an Adjuvant Chemotherapy Regimen for Patients With Node-Positive Primary Breast Cancer

Abstract: Purpose: This study was designed to determine whether increasing the dose of doxorubicin in or adding paclitaxel to a standard adjuvant chemotherapy regimen for breast cancer patients would prolong time to recurrence and survival Patients and Methods: After surgical treatment, 3,121 women with operable breast cancer and involved lymph nodes were randomly assigned to receive a combination of cyclophosphamide (C), 600 mg/m2, with one of three doses of doxorubicin (A), 60, 75, or 90 mg/m2, for four cycles followed by either no further therapy or four cycles of paclitaxel at 175 mg/m2 Tamoxifen was given to 94% of patients with hormone receptor–positive tumors Results: There was no evidence of a doxorubicin dose effect At 5 years, disease-free survival was 69%, 66%, and 67% for patients randomly assigned to 60, 75, and 90 mg/m2, respectively The hazard reductions from adding paclitaxel to CA were 17% for recurrence (adjusted Wald χ2 P = 0023; unadjusted Wilcoxon P = 0011) and 18% for death (adjusted P

Individual and combined effects of age, breast density, and hormone replacement therapy use on the accuracy of screening mammography.

Abstract: Mammographic breast density and age are important predictors of the accuracy of screening mammography. Although use of hormone replacement therapy is not an independent predictor of accuracy, it pr...

The Effect on Tumor Response of Adding Sequential Preoperative Docetaxel to Preoperative Doxorubicin and Cyclophosphamide: Preliminary Results From National Surgical Adjuvant Breast and Bowel Project Protocol B-27

Abstract: Purpose: The National Surgical Adjuvant Breast and Bowel Project Protocol B-27 was designed to determine the effect of adding docetaxel after four cycles of preoperative doxorubicin and cyclophosphamide (AC) on clinical and pathological response rates and on disease-free and overall survival of women with operable breast cancer. Patients and Methods: Women (N = 2,411) with operable primary breast cancer were randomly assigned to receive either four cycles of preoperative AC followed by surgery (group I), or four cycles of AC followed by four cycles of docetaxel, followed by surgery (group II), or four cycles of AC followed by surgery and then four cycles of docetaxel (group III). Clinical and pathologic tumor responses to preoperative therapy were assessed. Results: Mean tumor size (4.5 cm) and other key characteristics were evenly balanced among the three treatment arms. Grade 4 toxicity was observed in 10.3% of 2,400 patients during AC treatment, and in 23.4% of 1584 patients during docetaxel treatment....

Body mass index, serum sex hormones, and breast cancer risk in postmenopausal women.

Abstract: Body mass index, serum sex hormones, and breast cancer risk in postmenopausal women. Background: Obesity is associated with increased breast cancer risk among postmenopausal women. We examined whether this association could be explained by the relationship of body mass index (BMI) with serum sex hormone concentrations. Methods: We analyzed individual data from eight prospective studies of postmenopausal women. Data on BMI and prediagnostic estradiol levels were available for 624 case subjects and 1669 control subjects; data on the other sex hormones were available for fewer subjects. The relative risks (RRs) with 95% confidence intervals (CIs) of breast cancer associated with increasing BMI were estimated by conditional logistic regression on case- control sets, matched within each study for age and recruitment date, and adjusted for parity. All statistical tests were two- sided. Results: Breast cancer risk increased with increasing BMI (P-trend = .002), and this increase in RR was substantially reduced by adjustment for serum estrogen concentrations. Adjusting for free estradiol reduced the RR for breast cancer associated with a 5 kg/m(2) increase in BMI from 1.19 (95% CI = 1.05 to 1.34) to 1.02 (95% CI = 0.89 to 1.17). The increased risk was also substantially reduced after adjusting for other estrogens (total estradiol, non-sex hormone-binding globulin- bound estradiol, estrone, and estrone sulfate), and moderately reduced after adjusting for sex hormone-binding globulin, whereas adjustment for the androgens (androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and testosterone) had little effect on the excess risk. Conclusion: The results are compatible with the hypothesis that the increase in breast cancer risk with increasing BMI among postmenopausal women is largely the result of the associated increase in estrogens, particularly bioavailable estradiol.

Progression to Malignancy in the Polyoma Middle T Oncoprotein Mouse Breast Cancer Model Provides a Reliable Model for Human Diseases

Abstract: Animal models are powerful tools to analyze the mechanism of the induction of human breast cancer. Here we report a detailed analysis of mammary tumor progression in one mouse model of breast cancer caused by expression of the polyoma middle T oncoprotein (PyMT) in the mammary epithelium, and its comparison to human breast tumors. In PyMT mice, four distinctly identifiable stages of tumor progression from premalignant to malignant stages occur in a single primary tumor focus and this malignant transition is followed by a high frequency of distant metastasis. These stages are comparable to human breast diseases classified as benign or in situ proliferative lesions to invasive carcinomas. In addition to the morphological similarities with human breast cancer, the expression of biomarkers in PyMT-induced tumors is also consistent with those associated with poor outcome in humans. These include a loss of estrogen and progesterone receptors as well as integrin-beta1 expression and the persistent expression of ErbB2/Neu and cyclinD1 in PyMT-induced tumors as they progress to the malignant stage. An increased leukocytic infiltration was also closely associated with the malignant transition. This study demonstrates that the PyMT mouse model is an excellent one to understand the biology of tumor progression in humans.

Influence of Estrogen Plus Progestin on Breast Cancer and Mammography in Healthy Postmenopausal Women: The Women’s Health Initiative Randomized Trial

Abstract: The large-scale Women's Health Initiative has confirmed that, in postmenopausal women, combined estrogen/ progestin therapy entails an increased risk of invasive breast cancer. The investigators have now explored this relationship in detail, characterizing the cancers that developed and seeking to learn whether hormonal effects on the mammogram can influence diagnosis. A total of 16,608 postmenopausal women 50 to 79 years of age, all with an intact uterus, were randomly assigned to receive active treatment (0.625 mg conjugated equine estrogens plus 2.5 mg medroxyprogesterone acetate daily in a single tablet) or placebo. The participants, seen at 40 clinical centers, were to be followed from 1993 to 1998 by annual clinical breast examinations and mammograms, but the trial was ended after a mean interval of 5.2 years. Intent-to-treat analyses demonstrated a hazard ratio of 1.24 for both total cancers and invasive cancers in women given hormone therapy compared with the placebo group. There was some suggestion of an increased risk for in situ breast cancer in hormone-treated women. An increased risk of breast cancer in treated women emerged after 3 years in those not receiving hormones previously and after 2 years in previously treated women. The findings were similar when women in specific risk categories were analyzed, and race and ethnicity were not significant factors. Invasive cancers associated with combined hormone therapy were larger than those in placebo recipients, more likely to be node-positive, and diagnosed when more advanced. There was, however, no difference in tumor grade or in the distribution of histologic types of breast cancer. After the first year, hormone-treated women more often had abnormal or highly suspicious mammograms than did those given placebo. In this prospective, randomized trial, combined estrogen/progestin treatment of postmenopausal women increased both breast cancer risk and the frequency of abnormal mammograms requiring medical assessment. In addition, cancers in treated women were more advanced when diagnosed than was the case for placebo recipients.

American Society of Clinical Oncology 2003 Update on the Role of Bisphosphonates and Bone Health Issues in Women With Breast Cancer

Abstract: Purpose: To update the 2000 ASCO guidelines on the role of bisphosphonates in women with breast cancer and address the subject of bone health in these women. Results: For patients with plain radiographic evidence of bone destruction, intravenous pamidronate 90 mg delivered over 2 hours or zoledronic acid 4 mg over 15 minutes every 3 to 4 weeks is recommended. There is insufficient evidence supporting the efficacy of one bisphosphonate over the other. Starting bisphosphonates in women who demonstrate bone destruction through imaging but who have normal plain radiographs is considered reasonable treatment. Starting bisphosphonates in women with only an abnormal bone scan but without evidence of bone destruction is not recommended. The presence or absence of bone pain should not be a factor in initiating bisphosphonates. In patients with a serum creatinine less than 3.0 mg/dL (265 μmol/L), no change in dosage, infusion time, or interval is required. Infusion times less than 2 hours with pamidronate or less t...

Aromatase Inhibitors in Breast Cancer

Abstract: Until recently, tamoxifen, a nonsteroidal antiestrogen, was the mainstay of endocrine treatment of breast cancer. However, new aromatase inhibitors that are many times more potent and specific than the first such agent, aminoglutethimide, are changing the management of breast cancer in postmenopausal women. This review discusses the role of aromatase inhibitors such as letrozole, anastrozole, and exemestane in the treatment of breast cancer.

Gene expression profiles of human breast cancer progression

Abstract: Although distinct pathological stages of breast cancer have been described, the molecular differences among these stages are largely unknown. Here, through the combined use of laser capture microdissection and DNA microarrays, we have generated in situ gene expression profiles of the premalignant, preinvasive, and invasive stages of human breast cancer. Our data reveal extensive similarities at the transcriptome level among the distinct stages of progression and suggest that gene expression alterations conferring the potential for invasive growth are already present in the preinvasive stages. In contrast to tumor stage, different tumor grades are associated with distinct gene expression signatures. Furthermore, a subset of genes associated with high tumor grade is quantitatively correlated with the transition from preinvasive to invasive growth.

Annual Report to the Nation on the Status of Cancer, 1975–2000, Featuring the Uses of Surveillance Data for Cancer Prevention and Control

Abstract: Background The American Cancer Society, the Centers for Disease Control and Prevention (CDC), the National Cancer Institute (NCI), and the North American Association of Central Cancer Registries (NAACCR) collaborate annually to update cancer rates and trends in the United States. This report updates statistics on lung, female breast, prostate, and colorectal cancers and highlights the uses of selected surveillance data to assist development of state-based cancer control plans. Methods Age-adjusted incidence rates from 1996 through 2000 are from state and metropolitan area cancer registries that met NAACCR criteria for highest quality. Death rates are based on underlying cause-of-death data. Long-term trends and rates for major racial and ethnic populations are based on NCI and CDC data. Incidence trends from 1975 through 2000 were adjusted for reporting delays. State-specific screening and risk factor survey data are from the CDC and other federal and private organizations. Results Cancer incidence rates for all cancer sites combined increased from the mid-1970s through 1992 and then decreased from 1992 through 1995. Observed incidence rates for all cancers combined were essentially stable from 1995 through 2000, whereas the delay-adjusted trend showed an increase that had borderline statistical significance (P =.05). Increases in the incidence rates of breast cancer in women and prostate cancer in men offset a long-term decrease in lung cancer in men. Death rates for all cancer sites combined decreased beginning in 1994 and stabilized from 1998 through 2000, resulting in part from recent revisions in cause-of-death codes. Death rates among men continued to decline throughout the 1990s, whereas trends in death rates among women were essentially unchanged from 1998 through 2000. Analysis of state data for the leading cancers revealed mixed progress in achieving national objectives for improving cancer screening, risk factor reduction, and decreases in mortality. Conclusions Overall cancer incidence and death rates began to stabilize in the mid- to late 1990s. The recent increase in the delay-adjusted trend will require monitoring with additional years of data. Further reduction in the burden of cancer is possible but will require the continuation of strong federal, state, local, and private partnerships to increase dissemination of evidence-based cancer control programs to all segments of the population.

Tamoxifen: a most unlikely pioneering medicine.

Abstract: For more than 25 years, tamoxifen has been the gold standard for the endocrine treatment of all stages of oestrogen-receptor-positive breast cancer, and the World Health Organization lists tamoxifen as an essential drug for the treatment of breast cancer. It is estimated that more than 400,000 women are alive today as a result of tamoxifen therapy, and millions more have benefited from palliation and extended disease-free survival. Interestingly, tamoxifen also became the first cancer chemopreventive approved by the Food and Drug Administration (FDA) for the reduction of breast-cancer incidence in both pre- and post-menopausal women at high risk. However, 40 years ago, it was hard to imagine that a non-toxic targeted treatment for breast cancer could be developed at all.

Anastrozole alone or in combination with tamoxifen versus tamoxifen alone for adjuvant treatment of postmenopausal women with early-stage breast cancer: results of the ATAC (Arimidex, Tamoxifen Alone or in Combination) trial efficacy and safety update analyses

Abstract: BACKGROUND: The first analysis of the ATAC (Arimidex, Tamoxifen Alone or in Combination) trial (median follow-up, 33 months) demonstrated that in adjuvant endocrine therapy for postmenopausal patients with early-stage breast cancer, anastrozole was superior to tamoxifen in terms of disease-free survival (DFS), time to recurrence (TTR), and incidence of contralateral breast cancer (CLBC). In the current article, the results of the first efficacy update, based on a median follow-up period of 47 months, are reported along with the results of an updated safety analysis, performed 7 months after the first analysis (median duration of treatment, 36.9 months). METHODS: DFS, TTR, CLBC incidence, and safety were assessed in the same patient group as in the first analysis of the ATAC trial. RESULTS: DFS estimates at 4 years remained significantly more favorable (86.9% vs. 84.5%, respectively) for patients receiving anastrozole compared with those receiving tamoxifen (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.76-0.99; P = 0.03). The benefit generated by anastrozole in terms of DFS was even greater in patients with hormone receptor-positive tumors (HR, 0.82; 95% CI, 0.70-0.96; P = 0.014). The HR for TTR also indicated a significant benefit for patients receiving anastrozole compared with those receiving tamoxifen (HR, 0.83; 95% CI, 0.71-0.96; P = 0.015), with additional benefit for patients with hormone receptor-positive tumors (HR, 0.78; 95% CI, 0.65-0.93; P = 0.007). CLBC incidence data also continued to favor anastrozole (odds ratio [OR], 0.62; 95% CI, 0.38-1.02; P = 0.062), and statistical significance was achieved in the hormone receptor-positive subgroup (OR, 0.56; 95% CI, 0.32-0.98; P = 0.042). The updated safety analysis also confirmed the findings of the first analysis, in that endometrial cancer (P = 0.007), vaginal bleeding and discharge (P < 0.001 for both), cerebrovascular events (P < 0.001), venous thromboembolic events (P < 0.001), and hot flashes (P < 0.001) all occurred less frequently in the anastrozole group, whereas musculoskeletal disorders and fractures (P < 0.001 for both) continued to occur less frequently in the tamoxifen group. These results indicated that the safety profile of anastrozole remained consistent. CONCLUSIONS: After an additional follow-up period, anastrozole continues to show superior efficacy, which is most apparent in the clinically relevant hormone receptor-positive population. Furthermore, anastrozole has numerous noteworthy advantages in terms of tolerability compared with tamoxifen. These findings suggest that the benefits of anastrozole are likely to be maintained in the long term and provide further support for the status of anastrozole as a valid treatment option for postmenopausal women with hormone-sensitive early-stage breast cancer. Copyright 2003 American Cancer Society.

Long-term efficacy and safety of zoledronic acid compared with pamidronate disodium in the treatment of skeletal complications in patients with advanced multiple myeloma or breast carcinoma: a randomized, double-blind, multicenter, comparative trial.

Abstract: BACKGROUND The goal of the current study was to compare the long-term (25-month) safety and efficacy of zoledronic acid with pamidronate in patients with bone lesions secondary to advanced breast carcinoma or multiple myeloma. METHODS Patients (n = 1648) were randomized to receive 4 mg or 8 mg (reduced to 4 mg) zoledronic acid as a 15-minute infusion or to receive 90 mg pamidronate as a 2-hour infusion every 3–4 weeks for 24 months. The primary endpoint was the proportion of patients with at least 1 skeletal-related event (SRE), defined as pathologic fracture, spinal cord compression, radiation therapy, or surgery to bone. Secondary analyses included time to first SRE, skeletal morbidity rate, and multiple-event analysis. Hypercalcemia of malignancy (HCM) was included as an SRE in some secondary analyses. RESULTS After 25 months of follow-up, zoledronic acid reduced the overall proportion of patients with an SRE and reduced the skeletal morbidity rate similar to pamidronate. Compared with pamidronate, zoledronic acid (4 mg) reduced the overall risk of developing skeletal complications (including HCM) by an additional 16% (P = 0.030). In patients with breast carcinoma, zoledronic acid (4 mg) was significantly more effective than pamidronate, reducing the risk of SREs by an additional 20% (P = 0.025) compared with pamidronate and by an additional 30% in patients receiving hormonal therapy (P = 0.009). Zoledronic acid (4 mg) and pamidronate were tolerated equally well. The most common adverse events included bone pain, nausea, and fatigue. CONCLUSIONS Long-term follow-up data confirm that zoledronic acid was more effective than pamidronate in reducing the risk of skeletal complications in patients with bone metastases from breast carcinoma and was of similar efficacy in patients with multiple myeloma. Cancer 2003. © 2003 American Cancer Society. DOI 10.1002/cncr.11701

Role of the Estrogen Receptor Coactivator AIB1 (SRC-3) and HER-2/neu in Tamoxifen Resistance in Breast Cancer

Abstract: Background: AIB1 (SRC-3) is an estrogen receptor (ER) coactivator that, when overexpressed in cultured cells, can reduce the antagonist activity of tamoxifen-bound ERs. Signaling through the HER-2 receptor pathway activates AIB1 by phosphorylation. To determine whether high AIB1 expression alone or together with HER-2 reduces the effectiveness of tamoxifen in breast cancer patients, we quantified expression of AIB1 and HER-2 in tumors from breast cancer patients with long-term clinical follow-up who received either no adjuvant therapy or adjuvant tamoxifen therapy after breast cancer surgery. Methods: AIB1 and HER-2 protein levels in tumors from 316 breast cancer patients were determined using western blot analysis. Molecular variables (e.g., expression of AIB1, ER, progesterone receptor, p53, Bcl-2), tumor characteristics, and patient outcome were assessed using Spearman rank correlation. Disease-free survival (DFS) curves were derived from Kaplan–Meier estimates, and the curves were compared by log-rank tests. The effect of AIB1 on DFS adjusted for other prognostic factors was assessed by multivariable analysis using the Cox proportional hazards model. All statistical tests were two-sided. Results: High AIB1 expression in patients not receiving adjuvant tamoxifen therapy was associated with better prognosis and longer DFS (P = .018, log-rank test). In contrast, for patients who did receive tamoxifen therapy, high AIB1 expression was associated with worse DFS (P = .049, logrank test), which is indicative of tamoxifen resistance. The test for interaction between AIB1 expression and tamoxifen therapy was statistically significant (P = .004). When expression of AIB1 and HER-2 were considered together, patients whose tumors expressed high levels of both AIB1 and HER-2 had worse outcomes with tamoxifen therapy than all other patients combined (P = .002, log-rank test). Conclusions: The antitumor activity of tamoxifen in patients with breast cancer may be determined, in part, by tumor levels of AIB1 and HER-2. Thus, AIB1 may be an important diagnostic and therapeutic target. [J Natl Cancer Inst 2003;95:353–61]

A Nomogram for Predicting the Likelihood of Additional Nodal Metastases in Breast Cancer Patients With a Positive Sentinel Node Biopsy

Abstract: Background:The standard of care for breast cancer patients with sentinel lymph node (SLN) metastases includes complete axillary lymph node dissection (ALND). However, many question the need for complete ALND in every patient with detectable SLN metastases, particularly those perceived to have a low risk of non-SLN metastases. Accurate estimates of the likelihood of additional disease in the axilla could assist greatly in decision-making regarding further treatment.