Austrian Breast and Colorectal Cancer Study Group, Vienna, Austria. Adjuvant endocrine therapy plus zoledronic acid in premenopausal women with early-stage breast cancer: 62-month follow-up from the ABCSG-12 randomised trial
ABSTRACT Analysis of the Austrian Breast and Colorectal Cancer Study Group trial-12 (ABCSG-12) at 48 months' follow-up showed that addition of zoledronic acid to adjuvant endocrine therapy significantly improved disease-free survival. We have now assessed long-term clinical efficacy including disease-free survival and disease outcomes in patients receiving anastrozole or tamoxifen with or without zoledronic acid.
ABSCG-12 is a randomised, controlled, open-label, two-by-two factorial, multicentre trial in 1803 premenopausal women with endocrine-receptor-positive early-stage (stage I-II) breast cancer receiving goserelin (3.6 mg every 28 days), comparing the efficacy and safety of anastrozole (1 mg per day) or tamoxifen (20 mg per day) with or without zoledronic acid (4 mg every 6 months) for 3 years. Randomisation (1:1:1:1 ratio) was computerised and based on the Pocock and Simon minimisation method to balance the four treatment arms across eight prognostic variables (age, neoadjuvant chemotherapy, pathological tumour stage; lymph-node involvement, type of surgery or locoregional therapy, complete axillary dissection, intraoperative radiation therapy, and geographical region). Treatment allocation was not masked. The primary endpoint was disease-free survival (defined as disease recurrence or death) and analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00295646; follow-up is ongoing.
At a median follow-up of 62 months (range 0-114.4 months), more than 2 years after treatment completion, 186 disease-free survival events had been reported (53 events in 450 patients on tamoxifen alone, 57 in 453 patients on anastrozole alone, 36 in 450 patients on tamoxifen plus zoledronic acid, and 40 in 450 patients on anastrozole plus zoledronic acid). Zoledronic acid reduced risk of disease-free survival events overall (HR 0.68, 95% CI 0.51-0.91; p=0.009), although the difference was not significant in the tamoxifen (HR 0.67, 95% CI 0.44-1.03; p=0.067) and anastrozole arms (HR 0.68, 95% CI 0.45-1.02; p=0.061) assessed separately. Zoledronic acid did not significantly affect risk of death (30 deaths with zoledronic acid vs 43 deaths without; HR 0.67, 95% CI 0.41-1.07; p=0.09). There was no difference in disease-free survival between patients on tamoxifen alone versus anastrozole alone (HR 1.08, 95% CI 0.81-1.44; p=0.591), but overall survival was worse with anastrozole than with tamoxifen (46 vs 27 deaths; HR 1.75, 95% CI 1.08-2.83; p=0.02). Treatments were generally well tolerated, with no reports of renal failure or osteonecrosis of the jaw. Bone pain was reported in 601 patients (33%; 349 patients on zoledronic acid vs 252 not on the drug), fatigue in 361 (20%; 192 vs 169), headache in 280 (16%; 147 vs 133), and arthralgia in 266 (15%; 145 vs 121).
Addition of zoledronic acid improved disease-free survival in the patients taking anastrozole or tamoxifen. There was no difference in disease-free survival between patients receiving anastrozole and tamoxifen overall, but those on anastrozole alone had inferior overall survival. These data show persistent benefits with zoledronic acid and support its addition to adjuvant endocrine therapy in premenopausal patients with early-stage breast cancer.
- SourceAvailable from: Thorsten Kühn
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- "In the adjuvant setting, three larger trials (ABSCG-12, ZO-FAST, and AZURE) have reported a prognostic benefit for at least some subgroups of breast cancer patients [4-6]. The ABCSG-12 study reported a disease-free survival (DFS) benefit in a population of premenopausal breast cancer patients when zoledronic acid was added to either anastrozole or tamoxifen, and suggested that this benefit is greatest in patients over the age of 40, who achieve a maximal estrogen blockade [5,7]. Similarly, the ZO-FAST study reported an improvement in DFS in postmenopausal breast cancer patients . "
ABSTRACT: The objective of this prospectively randomized phase II trial (Trial registration: EUCTR2004-004007-37-DE) was to compare the clinical response of primary breast cancer patients to neoadjuvant therapy with letrozole alone (LET) or letrozole and zoledronic acid (LET + ZOL). Patients were randomly assigned to receive either LET 2.5 mg/day (n = 79) or the combination of LET 2.5 mg/day and a total of seven infusions of ZOL 4 mg every 4 weeks (n = 89) for 6 months. Primary endpoint was clinical response rate as assessed by mammogram readings. The study was terminated prematurely due to insufficient recruitment. We report here on an exploratory analysis of this data. Central assessment of tumor sizes during the treatment period was available for 131 patients (66 LET, 65 LET + ZOL). Clinical responses (complete or partial) were seen in 54.5% (95%CI: 41.8-66.9) of the patients in the LET arm and 69.2% (95%CI: 56.6-80.1) of those in the LET + ZOL arm (P = 0.106). A multivariate model showed an OR of 1.72 (95%CI: 0.83-3.59) for the experimental arm. No increase in the clinical response rate was observed with the addition of ZOL to a neoadjuvant treatment regimen with LET. However a trend towards a better reponse in the LET + ZOL arm could be observed. This trend is consistent with previous studies that have investigated the addition of ZOL to chemotherapy, and it may support the evidence for a direct antitumor action of zoledronic acid.BMC Cancer 02/2014; 14(1):66. DOI:10.1186/1471-2407-14-66 · 3.32 Impact Factor
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- "However, while the Takahashi trial enrolled Japanese women, the other three studies primarily included Caucasian women. The ABCSG-12 trial  included premenopausal women with endocrine responsive breast cancers in their early stages. However, these patients were treated with goserelin for ovarian suppression, and as a result, these patients were considered postmenopausal. "
ABSTRACT: Zoledronic acid is a potent inhibitor of osteoclast-mediated bone resorption and has been widely used in bone metastasis malignancies and postmenopausal osteoporosis as a preventive therapy against skeletal-related events. The purpose of this study was to evaluate the clinical outcome of zoledronic acid as an adjuvant therapy for patients with early stage breast cancer. Entries in the PubMed and EMBASE databases up to 12 July 2013 were systematically reviewed. Online abstracts from the proceedings of the Annual Meetings of the American Society of Clinical Oncology (ASCO) (1992-2013) and the San Antonio Breast Cancer Symposium (SABCS) (2004-2013) were also reviewed. Primary endpoints included overall survival (OS) and disease-free survival (DFS), while secondary endpoints included bone metastasis-free survival (BMFS), distant metastasis-free survival (DMFS), and fracture-free rate (FFR). A total of eight studies including 3,866 subjects and 3,864 controls met our search criteria and were evaluated. The use of zoledronic acid was found to improve OS (relative risk (RR), 0.88; 95% confidence interval (CI), 0.77-1.01; p-value = 0.06) and DMFS (RR, 0.77; 95% CI, 0.60-1.00; p-value = 0.05). Furthermore, statistically significant benefits were associated with BMFS (RR, 0.81; 95% CI, 0.66-0.99; p-value = 0.04) and FFRs (RR, 0.75; 95% CI, 0.61-0.92; p-value = 0.007). In contrast, there was no significant difference in DFS with the application of zoledronic acid (RR, 0.88; 95% CI, 0.72-1.09; p-value = 0.24). Sensitivity analysis further identified the improvement of 5-year OS for the adjuvant zoledronic acid therapy in early stage breast cancer patients (RR, 0.86; 95% CI, 0.75-0.99; p-value = 0.03), while a borderline statistically significant benefit was observed for 5-year DFS (RR, 0.90; 95% CI, 0.81-1.00; p-value = 0.06). Zoledronic acid as an adjuvant therapy appears to improve the 5-year OS rate for early stage breast cancer patients, and was associated with a protective effect for the bone metastases and fractures evaluated in more than 7,000 patients. However, further research is needed to confirm our findings, and sub-group analyses according to menopause status or hormone status may provide further insight.Journal of Hematology & Oncology 10/2013; 6(1):80. DOI:10.1186/1756-8722-6-80 · 4.93 Impact Factor
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- "Three large prospective studies evaluated the impact of addition of ZOL to systemic treatment on survival (Table 4) [6,8,31]. The randomized open-label Austrian Breast and Colorectal Cancer Study Group (ABCSG)-12 trial (NCT00295646) evaluated the influence of adding ZOL to adjuvant endocrine therapy . "
ABSTRACT: The presence of disseminated tumor cells (DTC) in bone marrow (BM) of breast cancer patients is associated with reduced clinical outcome. Bisphosphonate treatment was shown to eradicate DTC from BM in several studies. This controlled randomized open-label multi-center study aimed to investigate the influence of zoledronic acid (ZOL) on DTC and survival of breast cancer patients (Clinical Trial Registration Number: NCT00172068). Patients with primary breast cancer and DTC-positive bone marrow were randomized to treatment with ZOL plus adjuvant systemic therapy (n = 40) or adjuvant systemic therapy alone (n = 46) between 03/2002 and 12/2004. DTC were identified by immunocytochemistry using the pancytokeratin antibody A45B/B3 and by cytomorphology. The change in DTC numbers at 12 months and 24 months versus baseline, as well as patient outcomes were evaluated. 86 patients could be included into survival analysis (median follow-up: 88 months, range: 8--108 mths). Patients in the control group were more likely to die during follow-up than those in the ZOL-group (11% vs. 2%, p = 0.106). 15% of patients in the control group presented with relapse whereas only 8% of ZOL group patients developed metastatic or recurrent disease during follow-up (p = 0.205). At 24 months, 16% of patients from the control group were still DTC positive, whereas all patients treated with ZOL became DTC negative (p = 0.032). Patients presenting with persistent DTC 12 months after diagnosis had significantly shorter overall survival (p = 0.011). Bisphosphonate therapy contributes to eradication of disseminated tumor cells. The positive influence of bisphosphonates on survival in the adjuvant setting may be due to their effects on DTC.Trial registrationClinicalTrials.gov Identifier: NCT00172068 [Zoledronic Acid in the Treatment of Breast Cancer With Minimal Residual Disease in the Bone Marrow (MRD-1)].BMC Cancer 10/2013; 13(1):480. DOI:10.1186/1471-2407-13-480 · 3.32 Impact Factor