Michael Seifert

Endocrine therapy plus zoledronic acid in premenopausal breast cancer.

BACKGROUND Ovarian suppression plus tamoxifen is a standard adjuvant treatment in premenopausal women with endocrine-responsive breast cancer. Aromatase inhibitors are superior to tamoxifen in postmenopausal patients, and preclinical data suggest that zoledronic acid has antitumor properties. METHODS We examined the effect of adding zoledronic acid to a combination of either goserelin and tamoxifen or goserelin and anastrozole in premenopausal women with endocrine-responsive early breast cancer. We randomly assigned 1803 patients to receive goserelin (3.6 mg given subcutaneously every 28 days) plus tamoxifen (20 mg per day given orally) or anastrozole (1 mg per day given orally) with or without zoledronic acid (4 mg given intravenously every 6 months) for 3 years. The primary end point was disease-free survival; recurrence-free survival and overall survival were secondary end points. RESULTS After a median follow-up of 47.8 months, 137 events had occurred, with disease-free survival rates of 92.8% in the tamoxifen group, 92.0% in the anastrozole group, 90.8% in the group that received endocrine therapy alone, and 94.0% in the group that received endocrine therapy with zoledronic acid. There was no significant difference in disease-free survival between the anastrozole and tamoxifen groups (hazard ratio for disease progression in the anastrozole group, 1.10; 95% confidence interval [CI], 0.78 to 1.53; P=0.59). The addition of zoledronic acid to endocrine therapy, as compared with endocrine therapy without zoledronic acid, resulted in an absolute reduction of 3.2 percentage points and a relative reduction of 36% in the risk of disease progression (hazard ratio, 0.64; 95% CI, 0.46 to 0.91; P=0.01); the addition of zoledronic acid did not significantly reduce the risk of death (hazard ratio, 0.60; 95% CI, 0.32 to 1.11; P=0.11). Adverse events were consistent with known drug-safety profiles. CONCLUSIONS The addition of zoledronic acid to adjuvant endocrine therapy improves disease-free survival in premenopausal patients with estrogen-responsive early breast cancer. (ClinicalTrials.gov number, NCT00295646.)

Adjuvant endocrine therapy plus zoledronic acid in premenopausal women with early-stage breast cancer: 5-year follow-up of the ABCSG-12 bone-mineral density substudy

BACKGROUND The Austrian Breast and Colorectal Cancer Study Group trial-12 (ABCSG-12) bone substudy assesses zoledronic acid for preventing bone loss associated with adjuvant endocrine therapy and reports on long-term findings of bone-mineral density (BMD) during 3 years of treatment and 2 years after completing adjuvant treatment with or without zoledronic acid. The aim of this substudy is to gain insight into bone health in this setting. METHODS ABCSG-12 is a randomised, open-label, phase III, 4-arm trial comparing tamoxifen (20 mg/day orally) and goserelin (3.6 mg subcutaneously every 28 days) versus anastrozole (1 mg/day orally) and goserelin (3.6 mg subcutaneously every 28 days), both with or without zoledronic acid (4 mg intravenously every 6 months) for 3 years in premenopausal women with endocrine-responsive breast cancer. This prospective bone subprotocol measured BMD at 0, 6, 12, 36, and 60 months. The primary endpoint of the bone substudy (secondary endpoint in the main trial) was change in BMD at 12 months, assessed by dual-energy X-ray absorptiometry in assessable patients. Analyses were intention to treat. Statistical significance was assessed by t tests. The ABCSG-12 trial is registered on the ClinicalTrials.gov website, number NCT00295646. FINDINGS 404 patients were prospectively included in the bone substudy and randomly assigned to endocrine therapy alone (goserelin and anastrozole or goserelin and tamoxifen; n=199) or endocrine therapy concurrent with zoledronic acid (goserelin, anastrozole, and zoledronic acid or goserelin, tamoxifen, and zoledronic acid; n=205). After 3 years of treatment, endocrine therapy alone caused significant loss of BMD at the lumbar spine (-11.3%, mean difference -0.119 g/cm(2) [95% CI -0.146 to -0.091], p<0.0001) and trochanter (-7.3%, mean difference -0.053 g/cm(2) [-0.076 to -0.030], p<0.0001). In patients who did not receive zoledronic acid, anastrozole caused greater BMD loss than tamoxifen at 36 months at the lumbar spine (-13.6%, mean difference -0.141 g/cm(2) [-0.179 to -0.102] vs -9.0%, mean difference -0.095 g/cm(2) [-0.134 to -0.057], p<0.0001 for both). 2 years after the completion of treatment (median follow-up 60 months [range 15.5-96.6]), patients not receiving zoledronic acid still had decreased BMD at both sites compared with baseline (lumbar spine -6.3%, mean difference -0.067 g/cm(2) [-0.106 to -0.027], p=0.001; trochanter -4.1%, mean difference -0.03 g/cm(2) [-0.062 to 0.001], p=0.058). Patients who received zoledronic acid had stable BMD at 36 months (lumbar spine +0.4%, mean difference 0.004 g/cm(2) [-0.024 to 0.032]; trochanter +0.8%, mean difference 0.006 g/cm(2) [-0.018 to 0.028]) and increased BMD at 60 months at both sites (lumbar spine +4.0%, mean difference 0.039 g/cm(2) [0.005-0.075], p=0.02; trochanter +3.9%, mean difference 0.028 g/cm(2) [0.003-0.058], p=0.07) compared with baseline. INTERPRETATION Goserelin plus tamoxifen or anastrozole for 3 years without concomitant zoledronic acid caused significant bone loss. Although there was partial recovery 2 years after completing treatment, patients receiving endocrine therapy alone did not recover their baseline BMD levels. Concomitant zoledronic acid prevented bone loss during therapy and improved BMD at 5 years.

Randomized Adjuvant Trial of Tamoxifen and Goserelin Versus Cyclophosphamide, Methotrexate, and Fluorouracil: Evidence for the Superiority of Treatment With Endocrine Blockade in Premenopausal Patients With Hormone-Responsive Breast Cancer—Austrian Breast and Colorectal Cancer Study Group Trial 5

PURPOSE Effective adjuvant treatment modalities in premenopausal breast cancer patients today include chemotherapy, ovariectomy, and tamoxifen administration. The purpose of Austrian Breast and Colorectal Cancer Study Group Trial 5 was to compare the efficacy of a combination endocrine treatment with standard chemotherapy. PATIENTS AND METHODS Assessable trial subjects (N = 1,034) presenting with hormone-responsive disease were randomized to receive either 3 years of goserelin plus 5 years of tamoxifen or six cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF). Stratification criteria included tumor stage and grade, number of involved nodes, type of surgery, and steroid hormone receptor content. Relapse-free survival (RFS) was defined as time from randomization to first relapse, local recurrence, or contralateral incidence, and overall survival (OS) as time to date of death. RESULTS With a 60-month median follow-up, 17.2% of patients in the endocrine group and 20.8% undergoing chemotherapy developed relapses. Local recurrences emerged in 4.7% and 8.0%, respectively. RFS and local recurrence-free survival differed significantly in favor of endocrine therapy (P =.037 and P =.015), with a similar trend observed in OS (P =.195). CONCLUSION Overall, our data suggest that the goserelin-tamoxifen combination is significantly more effective than CMF in the adjuvant treatment of premenopausal patients with stage I and II breast cancer.

Vascular endothelial growth factor (VEGF) in human breast cancer : Correlation with disease-free survival

Studies have shown that microvessel density influences breast‐cancer prognosis. Since tumor angiogenesis is considered to be substantially affected by the excretion of vascular endothelial growth factor (VEGF) from tumor cells, we examined whether VEGF concentration is different in malignant and in non‐malignant breast tissue. It was also of interest to discover whether intratumoral VEGF concentration influences disease‐free survival (DFS) of breast‐cancer patients. Analysis is based on 120 tissue specimens taken from breast fibromas (n = 23), normal epithelial breast tissue adjacent to fibromas (n = 8) and invasive breast cancer (n = 89). VEGF concentration was quantified by using an immunoassay. Microvessel density was determined by immunostaining for factor‐VIII‐related antigen. Median VEGF concentration is given in pg/mg protein (25%‐quantile—75%‐quantile) and it was 0 (0–1.8) in normal breast tissue, 9.8 (0.52–43.0) in fibromas and 130.4 (50.8–362.2) in invasive carcinomas. A univariate Cox model revealed that node status, tumor size, estrogen‐receptor concentration, histological grading and microvessel density were prognostic factors for disease‐free survival in breast cancer. We found a significant correlation between VEGF concentration and microvessel count, but VEGF concentration did not significantly influence disease‐free survival. Although VEGF protein was found at a significantly higher concentration in malignant than in non‐malignant tissue, determination of intratumoral VEGF protein by an enzyme immunoassay was not prognostically relevant in our patient population. Int. J. Cancer 74:455–458, 1997.

Zoledronic acid combined with adjuvant endocrine therapy of tamoxifen versus anastrozol plus ovarian function suppression in premenopausal early breast cancer: final analysis of the Austrian Breast and Colorectal Cancer Study Group Trial 12

BACKGROUND Zoledronic acid (ZOL) plus adjuvant endocrine therapy significantly improved disease-free survival (DFS) at 48- and 62-month follow-up in the ABCSG-12 trial. We present efficacy results of a final additional analysis after 94.4 months. PATIENTS AND METHODS Patients were premenopausal women who had undergone primary surgery for stage I/II estrogen-receptor-positive and/or progesterone-receptor-positive breast cancer with <10 positive lymph nodes, and were scheduled for standard goserelin therapy. All 1803 patients received goserelin (3.6 mg every 28 days) and were randomized to tamoxifen (20 mg/days) or anastrozole (1 mg/days), both with or without ZOL (4 mg every 6 months) for 3 years. The primary end point was DFS; recurrence-free survival and overall survival (OS) were secondary end points. RESULTS After 94.4-month median follow-up (range, 0-114 months), relative risks of disease progression [hazard ratio (HR) = 0.77; 95% confidence interval (CI) 0.60-0.99; P = 0.042] and of death (HR = 0.66; 95% CI 0.43-1.02; P = 0.064) are still reduced by ZOL although no longer significant at the predefined significance level. Overall, 251 DFS events and 86 deaths were reported. Absolute risk reductions with ZOL were 3.4% for DFS and 2.2% for OS. There was no DFS difference between tamoxifen alone versus anastrozole alone, but there was a pronounced higher risk of death for anastrozole-treated patients (HR = 1.63; 95% CI 1.05-1.45; P = 0.030). Treatments were generally well tolerated, with no reports of renal failure or osteonecrosis of the jaw. CONCLUSION These final results from ABCSG 12 suggest that twice-yearly ZOL enhances the efficacy of adjuvant endocrine treatment, and this benefit is maintained long-term. CLINICALTRIALSGOV NCT00295646 (http://www.clinicaltrials.gov/ct2/results?term=00295646).

MMP-2 and MMP-9 Expression in Breast Cancer-Derived Human Fibroblasts is Differentially Regulated by Stromal-Epithelial Interactions

Tissue remodeling is a key element in the local invasion and metastasis of malignant breast tumors. The degradation of extracellular matrix that is associated with this process is thought to be mediated by a number of Zn2+-dependent matrix metalloproteinases (MMPs). In most cases these enzymes are not produced by the malignant epithelium itself but by adjacent breast stroma, suggesting an important role for cell-cell interactions. We have analyzed Gelatinase A (MMP-2) and Gelatinase B (MMP-9) gene expression in a panel of six breast cancer cell lines and six primary cultures of stromal cells deriving from breast cancer biopsies. With one exception we did not detect MMP-2 or MMP-9 gene expression in any of the established tumor cell lines. Conversely, tumor stroma-derived fibroblasts expressed MMP-2 mRNA, although no MMP-9 mRNA was seen in RNase protection assays. When fibroblasts were cultured in the presence of media conditioned by MCF-7 tumor cells, MMP-2 enzyme production increased but MMP-9 activity remained undetectable. However, when fibroblasts and MCF-7 tumor cells were co-cultured together, MMP-9 was induced. These observations were confirmed by immunocytochemical analysis of co-cultures of MCF-7 and tumor-derived fibroblasts in which MMP-2 and MMP-9 protein expression was confined to stromal cells adjacent to MCF-7 tumor cells. No MMP-2 or MMP-9 staining was detected in monocultures of the two respective cell types. We conclude that MMP-2 expression is present in the stroma of malignant tumors and is increased by paracrine stimulation mediated by soluble factors. In contrast, MMP-9 expression tumor-derived fibroblasts requires direct contact with malignant tumor epithelium.

Tissue Expression and Serum Levels of HER-2/neu in Patients with Breast Cancer

We have analyzed serum levels of soluble HER-2/neu in 42 primary breast cancer patients prior to any therapy and studied the relationship between the overexpression and amplification of HER-2/neu in the primary tumor after surgical excision and data obtained by pathohistological staging. In addition, we have investigated the sera of 62 patients with stage IV breast cancer. Using an enzyme-linked immunosorbent assay, we observed elevated serum HER-2/neu levels in 6/42 (14.2%) preoperative patients. In 42.8% of the patients with HER-2/neu tumor expression/amplification serum levels were increased. In contrast, only 8.5% of the patients without HER-2/neu expression/amplification in the primary tumor presented with elevated serum levels. There was a significant correlation between serum concentrations of soluble HER-2/neu and tumor size (p < 0.0001) or axillary lymph node involvement (p < 0.0001). In patients with stage IV disease, 27 of 62 (43.5%) had elevated soluble HER-2/neu serum levels. A highly significant correlation between soluble HER-2/ neu and CA 15-3 (p < 0.002) was observed. The correlation of serum concentrations of HER-2/neu with estrogen and progesterone receptor status of the primary tumor was not significant in both groups. In conclusion, the measurement of serum HER-2/neu levels at diagnosis defines a small subgroup of breast cancer patients with a relatively advanced stage of disease. Its strong correlation with tumor load in patients with stage II disease and the high prevalence in patients with stage IV disease could make it a promising tool for the assessment of disease activity and biologic behavior in breast cancer.

Expression of estrogen receptor beta isoforms in human breast cancer tissues and cell lines.

Estrogen receptor alpha (ER-α) is an important regulator of growth and differentiation in the mammary gland and the female reproductive tract. It is also involved in the development of malignant tumors. The human ER-β is highly homologous to the extensively studied human ER-α. It binds to the endogenous 17β-estradiol with similar affinity as ER-α and the transcriptional activity through the consensus ERE can be stimulated. Five ER-β isoforms were cloned and characterized. They diverge at a common position within the predicted helix 10 of the ligand-binding domain of the human ER-β, with nucleotide sequences consistent with different exon usage. These isoforms of human ER-β show differential expression in tissues and in tumor cell lines. Furthermore, they are predicted to form DNA-binding heterodimers when coexpressed. Expression of some of the ER-β isoforms in human breast tissue, breast cancer, and breast cancer cell lines were reported by several groups. However, there is no complete analysis of the gene expression pattern of all ER-β isoforms in breast cancer so far. In this study, we examined the mRNA expression of each of the ER-β isoforms in 30 tumors from breast cancer patients and 21 breast cell lines. In conclusion, expression of ER-β1, ER-β2, and ER-β5 were observed in different cell lines as well as in the tumors, ER-β4 isoform was expressed in all samples, and ER-β3 isoform was not detected in any of the samples examined. There were no associations of the expression of all ER-β isoforms with the invasiveness of the cell lines as well as with clinical parameters of the tumors.

Randomized trial of tamoxifen versus tamoxifen plus aminoglutethimide as adjuvant treatment in postmenopausal breast cancer patients with hormone receptor-positive disease: Austrian breast and colorectal cancer study group trial 6.

PURPOSE To determine whether the addition of aminoglutethimide to tamoxifen is able to improve the outcome in postmenopausal patients with hormone receptor-positive, early-stage breast cancer. PATIENTS AND METHODS A total of 2,021 postmenopausal women were randomly assigned to receive either tamoxifen for 5 years alone or tamoxifen in combination with aminoglutethimide (500 mg/d) for the first 2 years of treatment. Tamoxifen was administered at 40 mg/d for the first 2 years and at 20 mg/d for 3 years. RESULTS All randomized and eligible patients were included in the analysis according to the intention-to-treat principle. After a median follow-up of 5.3 years, the 5-year disease-free survival in the aminoglutethimide plus tamoxifen group was 83.6% versus 83.7% in the monotherapy group (P =.89). The corresponding data for overall survival at 5 years were 91.4% and 91.2%, respectively (P =.74). More patients failed to complete combination treatment (13.7%) because of side effects as compared to tamoxifen alone (5.2%; P =.0001). CONCLUSION Aminoglutethimide given for 2 years in addition to tamoxifen for 5 years does not improve the prognosis of postmenopausal patients with receptor-positive, lymph node-negative or lymph node-positive breast cancer.

Prognostic Significance of Mutations in the p53 Gene, Particularly in the Zinc-binding Domains, in Lymph Node- and Steroid Receptor Positive Breast Cancer Patients

The aim of our study was to evaluate if p53 mutations, especially those in the L2/L3 domains of the p53 gene, add prognostic information for node-positive and steroid receptor positive breast cancer patients. Two hundred and five tumour samples from a randomised clinical trial of 596 lymph node- and steroid receptor positive breast cancer patients were included. All patients had been randomly allocated to receive 20 mg of adjuvant tamoxifen (TAM) daily for 2 years or TAM plus one cycle of low-dose, short-term chemotherapy. For detection of p53 mutations we used in vitro amplification by polymerase chain reaction and consecutively performed temperature gradient gel electrophoresis (PCR-TGGE) and direct sequencing. We found p53 mutations in 42/205 (20%) cases: 16/42 (38%) p53 mutations occurred within the L2/L3 domains of the p53 gene, and 26/42 (62%) outside the L2/L3 domains. p53 mutation served as a statistically significant parameter in predicting disease-free survival in univariate (P = 0.02) and multivariate (P = 0.009) analysis. For overall survival, no significant differences were observed. Patients with tumours that had p53 mutations within the L2/L3 domains of the gene showed no significant difference to those with mutations outside the L2/L3 domains for disease-free survival. For overall survival, mutations in the L2/L3 domains showed a marginally significant difference (P = 0.05) in multivariate analysis, but not in univariate analysis (P = 0.13). We conclude that mutation in the L2/L3 domains of the p53 gene is not an independent prognostic indicator of disease outcome for patients suffering from breast cancer with lymph node metastases and positive steroid receptors.