Long-Term Outcomes of Adjuvant Denosumab in Breast Cancer

Adjuvant denosumab for early breast cancer-Evidence and controversy

The efficacy of adjuvant denosumab in combination with hormonotherapy in breast cancer patients was investigated in two randomized trials, ABCSG-18 and D-Care, but the results were mixed with respect to the impact of this drug on disease-free survival. However, the ABCSG-18 study has achieved its primary goal: prevention of clinical fractures. Therefore, the protective role of Denosumab on bone fragility induced by estrogen deprivation, already demonstrated in post-menopausal women, has been validated in the breast cancer setting.

[Osteoporosis-Definition, risk assessment, diagnosis, prevention and treatment (update 2024) : Guidelines of the Austrian Society for Bone and Mineral Research]

BACKGROUND

Austria is among the countries with the highest incidence and prevalence of osteoporotic fractures worldwide. Guidelines for the prevention and management of osteoporosis were first published in 2010 under the auspices of the then Federation of Austrian Social Security Institutions and updated in 2017. The present comprehensively updated guidelines of the Austrian Society for Bone and Mineral Research are aimed at physicians of all specialties as well as decision makers and institutions in the Austrian healthcare system. The aim of these guidelines is to strengthen and improve the quality of medical care of patients with osteoporosis and osteoporotic fractures in Austria.

METHODS

These evidence-based recommendations were compiled taking randomized controlled trials, systematic reviews and meta-analyses as well as European and international reference guidelines published before 1 June 2023 into consideration. The grading of recommendations used ("conditional" and "strong") are based on the strength of the evidence. The evidence levels used mutual conversions of SIGN (1++ to 3) to NOGG criteria (Ia to IV).

RESULTS

The guidelines include all aspects associated with osteoporosis and osteoporotic fractures, such as secondary causes, prevention, diagnosis, estimation of the 10-year fracture risk using FRAX®, determination of Austria-specific FRAX®-based intervention thresholds, drug-based and non-drug-based treatment options and treatment monitoring. Recommendations for the office-based setting and decision makers and institutions in the Austrian healthcare system consider structured care models and options for osteoporosis-specific screening.

CONCLUSION

The guidelines present comprehensive, evidence-based information and instructions for the treatment of osteoporosis. It is expected that the quality of medical care for patients with this clinical picture will be substantially improved at all levels of the Austrian healthcare system.

The use of denosumab in osteoporosis - an update on efficacy and drug safety

INTRODUCTION

Denosumab (Prolia) is a fully human monoclonal antibody against the receptor activator of the nuclear factor kappaB ligand. It is a potent antiresorptive agent that reduces osteoclastogenesis.

AREAS COVERED

Denosumab has been shown to improve bone mineral density and reduce the incidence of new fractures in postmenopausal women and men. It is also used in the treatment of glucocorticoid-induced osteoporosis, as well as for the prevention of bone loss and reduction of fracture risk in men receiving androgen deprivation therapy for non-metastatic prostate cancer and women receiving adjuvant aromatase inhibitor therapy for breast cancer. Initial safety concerns included infections, cancer, skin reactions, cardiovascular disease, hypocalcemia, osteonecrosis of the jaw, and atypical femur fractures; however, further study and experience provide reassurance on these issues. Anecdotal reports have raised concerns about an increased risk of multiple vertebral fractures following discontinuation of denosumab.

EXPERT OPINION

Although bisphosphonates are often selected as initial therapy for osteoporosis, denosumab may be an appropriate initial therapy in patients at high risk for fracture, including older patients who have difficulty with the dosing requirements of oral bisphosphonates, as well as patients who are intolerant of, unresponsive to, or have contraindications to other therapies. Additional data is needed to address questions regarding treatment duration and discontinuation.

MASCC/ISOO Clinical Practice Statement: Adjuvant bone-modifying agents in primary breast cancer patients - prevention of medication-related osteonecrosis of the jaw

PURPOSE

A MASCC/ISOO Clinical Practice Statement (CPS) is aimed at generating a concise tool for clinicians that concentrates practical information needed for the management of oral complications of cancer patients. This CPS raises awareness to the prevention of medication-related osteonecrosis of the jaw (MRONJ) in patients with breast cancer treated with adjuvant bone-modifying agents (BMA).

METHODS

This CPS was developed based on a critical evaluation of the literature followed by a structured discussion of a group of leading experts, members of the Oral Care Study Group of MASCC/ISOO. The information is presented in the form of succinct bullets and tables to generate a short manual about the best standard of care.

RESULTS

In patients treated with adjuvant BMA, dento-alveolar surgery poses a moderate risk for MRONJ that ranges between the high risk for MRONJ in patients with metastatic breast cancer and the low risk for MRONJ in patients with osteoporosis. Existing MRONJ guidelines serve as a starting point for adjuvant BMA use. Urgent procedures should be delivered without delay using the accepted precautions to prevent MRONJ. If elective surgery is considered, the individual risk for MRONJ following surgery should be assessed according to common risk factors.

CONCLUSION

Prevention of MRONJ in primary breast cancer patients treated with adjuvant BMA requires risk-benefit assessment; collaboration between the medical team, dental professional, and patient; and patient-specific tailored dental treatment planning. The patient should be informed about this risk. Additional research is needed to define optimal MRONJ care for this population.

Cancer risk in patients treated with denosumab compared with alendronate: A population-based cohort study

BACKGROUND

Antiresorptive treatment is currently used in millions of patients with osteoporosis and cancer worldwide. Early studies of denosumab suggested a small signal in ovarian cancer incidence and emerging data suggest that denosumab stimulates germ cell proliferation in the gonads. This study aims to determine the association between the use of denosumab and the risk of reproductive cancers compared with the use of alendronate.

RESEARCH DESIGN AND METHODS

Using a cohort study design, we used the Danish nationwide registries to identify a population of subjects ≥50 years of age during 2010-2017 who started denosumab after being on alendronate treatment for at least six months. The cohort was matched 1:2 with patients who had been treated with alendronate alone for at least six months. The risk of reproductive cancers and the risk difference between groups were estimated using the Longitudinal Targeted Maximum Likelihood Estimation (L-TMLE) method.

RESULTS

We identified 6054 Danish individuals who underwent treatment with denosumab. These individuals were matched with 12,108 receiving alendronate. The absolute risk of reproductive cancer was 1.05 % (95 % CI 0.75-1.34) after three years for denosumab users and was not different 0.03 % (-0.34-0.39) than for alendronate users. In supplemental analyses, there was no increased risk of non-reproductive cancers associated with the use of denosumab (risk difference of 0.54 % (-0.41-1.19). Analysis comparing denosumab users with the general population gave similar results.

CONCLUSION

There was no difference in the risk of cancer following treatment with denosumab compared to treatment with alendronate assessed after a short follow-up of 3 years.

Assessing Knowledge, Competence, and Performance Following Web-Based Education on Early Breast Cancer Management: Health Care Professional Questionnaire Study and Anonymized Patient Records Analysis

BACKGROUND

Web-based learning activities are key components of continuing medical education (CME) for health care professionals (HCPs). However, the published outcomes of web-based educational interventions for early breast cancer (EBC) are limited.

OBJECTIVE

This study aims to objectively assess knowledge, competence, and performance among HCPs following participation in 2 EBC-focused CME activities and to identify the remaining educational gaps.

METHODS

We developed 2 CME-accredited web-based educational activities addressing high-risk EBC, including integration of shared decision-making to optimize patient care (touchMDT) and stratification for early identification of high-risk patients and novel treatment strategies (touchPANEL DISCUSSION). Knowledge, competence, and performance were assessed before and after the activities against an expanded outcomes framework (levels 1-5) using self-reported questionnaires and an analysis of anonymized data extracted from patient records.

RESULTS

Six months after the launch of the activity, 7047 and 8989 HCP participants engaged with touchMDT and touchPANEL DISCUSSION, respectively. The overall satisfaction was 82% (a total score of 20.6 out of 25) for the touchMDT and 88% (a total score of 21.9 out of 25) for the touchPANEL DISCUSSION. For the evaluation of knowledge and competence (50 respondents before the activity and 50 learners after the activity), there was a significant increase in the mean number of correctly answered questions from pre- to postactivity (touchMDT: median 4.0, IQR 3.0-5.0 to median 5.5, IQR 4.0-7.0; mean 4.00, SD 1.39 to mean 5.30, SD 1.56 and touchPANEL DISCUSSION: median 4.0, IQR 4.0-5.0 to median 6.0, IQR 5.0-7.0; mean 4.32, SD 1.30 to mean 5.88, SD 1.49; both P<.001). A significant improvement in self-reported performance (50 respondents before the activity and 50 learners after the activity) was observed in a combined analysis of both activities (median 3.0, IQR 2.0-3.0 to median 4.0, IQR 3.0-5.0; mean 2.82, SD 1.08 to mean 4.16, SD 1.45; P<.001). Patient record analysis (50 respondents before the activity and 50 learners after the activity) showed that the HCPs used a range of measures to determine EBC recurrence risk and revealed no significant differences in adjuvant therapies used before and after the activity (P=.97 and P>.99 for Ki-67 <20% and Ki-67 ≥20% tumors, respectively). The remaining educational gaps included strategies for implementing shared decision-making in clinical practice and the use of genetic and biomarker testing to guide treatment selection.

CONCLUSIONS

Brief, web-based CME activities on EBC were associated with an improvement in HCP knowledge, competence, and self-reported performance and can help identify unmet needs to inform the design of future CME activities.

RANK Expression as an Independent Predictor for Response to Neoadjuvant Chemotherapy in Luminal-Like Breast Cancer: A Translational Insight from the GeparX Trial

PURPOSE

The GeparX study investigated whether denosumab as add-on treatment to nab-paclitaxel-based neoadjuvant chemotherapy (NACT) with two different schedules (125 mg/m² weekly vs. day 1, 8 every 22 days) may increase pathologic complete response (pCR) rate. The addition of denosumab to NACT did not improve pCR rates as recently published. In this study, we investigated whether receptor activator of nuclear factor-kappa B (RANK) expression, as part of the denosumab target pathway: (i) may retrospectively identify a subgroup of patients with additional clinical benefit of denosumab or (ii) may predict response to nab-paclitaxel NACT.

EXPERIMENTAL DESIGN

RANK protein was IHC-stained on pre-therapeutic core biopsies from patients of the GeparX study (n = 667) with the antibody RANK/Envision System HRP (DAB) and was analyzed for the percentage of membranous RANK tumor cell staining (>5% RANKhigh vs. ≤5% RANKlow).

RESULTS

We could not identify any patient subgroup with differential response under denosumab add-on treatment in patients with RANKhigh expression [139/667, 20.8%; OR, 0.86; 95% confidence interval (CI), 0.44-1.68; P = 0.667] or RANKlow expression (528/667 (79.2%) OR, 1.10; 95% CI, 0.78-1.56; P = 0.589; Pinteraction = 0.528). However, the pCR rate was higher in the RANKhigh subgroup compared with RANKlow (50% vs. 39%; OR, 1.52; 95% CI, 1.04-2.21; P = 0.037). RANK expression constituted an independent predictor of response to NACT frequently in patients with luminal-like subtype (HR+/HER2-; OR, 2.98; 95% CI, 1.30-6.79; P = 0.010). No predictive value of RANK expression among the different nab-paclitaxel regimens was observed.

CONCLUSION

We report RANK expression to be an independent predictive biomarker for response to NACT in patients with luminal-like breast cancer.

Understanding breast cancer complexity to improve patient outcomes: The St Gallen International Consensus Conference for the Primary Therapy of Individuals with Early Breast Cancer 2023

The 18th St Gallen International Breast Cancer Conference held in March 2023, in Vienna, Austria, assessed significant new findings for local and systemic therapies for early breast cancer with a focus on the evaluation of multimodal treatment options. The emergence of more effective, innovative agents in both the preoperative (primary or neoadjuvant) and post-operative (adjuvant) settings has underscored the pivotal role of a multidisciplinary approach in treatment decision making, particularly when selecting systemic therapy for an individual patient. The importance of multidisciplinary discussions regarding the clinical benefits of interventions was explicitly emphasized by the consensus panel as an integral part of developing an optimal treatment plan with the 'right' degree of intensity and duration. The panelists focused on controversies surrounding the management of common ductal/no special type and lobular breast cancer histology, which account for the vast majority of breast tumors. The expert opinion of the panelists was based on interpretations of available data, as well as current practices in their professional environments, personal and socioeconomic factors affecting patients, and cognizant of varying reimbursement and accessibility constraints around the world. The panelists strongly advocated patient participation in well-designed clinical studies whenever feasible. With these considerations in mind, the St Gallen Consensus Conference aims to offer guidance to clinicians regarding appropriate treatments for early-stage breast cancer and assist in balancing the realistic trade-offs between treatment benefit and toxicity, enabling patients and clinicians to make well-informed choices through a shared decision-making process.

Systemic therapy for hormone receptor-positive/human epidermal growth factor receptor 2-negative early stage and metastatic breast cancer

Hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer is defined by the presence of the estrogen receptor and/or the progesterone receptor and the absence of HER2 gene amplification. HR-positive/HER2-negative breast cancer accounts for 65%-70% of all breast cancers, and incidence increases with increasing age. Treatment varies by stage, and endocrine therapy is the mainstay of treatment in both early stage and late-stage disease. Combinations with cyclin-dependent kinase 4/6 inhibitors have reduced distant recurrence in the early stage setting and improved overall survival in the metastatic setting. Chemotherapy is used based on stage and tumor biology in the early stage setting and after endocrine resistance for advanced disease. New therapies, including novel endocrine agents and antibody-drug conjugates, are now changing the treatment landscape. With the availability of new treatment options, it is important to define the optimal sequence of treatment to maximize clinical benefit while minimizing toxicity. In this review, the authors first discuss the pathologic and molecular features of HR-positive/HER2-negative breast cancer and mechanisms of endocrine resistance. Then, they discuss current and emerging therapies for both early stage and metastatic HR-positive/HER2-negative breast cancer, including treatment algorithms based on current data.

Managing a Long and Winding Road: Estrogen Receptor-Positive Breast Cancer

We review key topics in the management of estrogen receptor (ER)-positive human epidermal growth factor receptor 2-negative breast cancer. The single biggest challenge in management of this disease is late relapse, and we review new methods for identifying which patients are at risk of late relapse and potential therapeutic approaches in clinical trials. CDK4/6 inhibitors have become a standard treatment option for high-risk patients in both the adjuvant setting and the first-line metastatic setting, and we review data on optimal treatment after progression on CDK4/6 inhibitors. Targeting the estrogen receptor remains the single most effective way of targeting the cancer, and we review the developments in new oral selective ER degraders that are becoming a standard of care in cancers with ESR1 mutations and potential future directions.

Adjuvant denosumab in early breast cancer: a systematic review and meta-analysis of randomized controlled clinical trials

Background

In early breast cancer (BC) the impact of denosumab on survival outcomes is still unclear. We undertook a systematic review and meta-analysis to assess efficacy and safety of adjuvant denosumab in addition to standard anticancer therapy.

Methods

PubMed, CENTRAL, Scopus, Embase, and oncological meetings websites were screened to identify potentially eligible randomized controlled trials (RCTs). Survival outcomes were disease-free survival (DFS), bone-metastasis-free survival (BMFS), and overall survival (OS). Fracture incidence and time to first fracture were bone-health outcomes. Osteonecrosis of the jaw (ONJ), atypical femur fractures (AFF), and other adverse events were also evaluated. Pooled hazard ratios (HRs) and risk ratios (RR) with respective 95% confidence interval (95% CI) were computed using a random-effects model. Exploratory subgroup analyses were performed.

Results

Two phase III RCTs were included, the Austrian Breast & Colorectal Cancer Study Group-18 (ABCSG-18) and the D-CARE trials, for a total of 7929 patients. In the ABCSG-18 trial, denosumab was administered every 6 months during endocrine therapy (for a median of seven cycles) while the D-CARE trial used an intensive schedule for a total treatment duration of 5 years. Adjuvant denosumab showed no difference in DFS (HR: 0.932; 95% CI: 0.748-1.162), BMFS (HR: 0.9896; 95% CI: 0.751-1.070), and OS (HR: 0.917; 95% CI: 0.718-1.171) compared to placebo in the overall population. In hormone receptor positive/human epidermal growth factor receptor 2 (HER2) negative BC patients, a DFS (HR: 0.883; 95% CI: 0.782-0.996) and BMFS (HR: 0.832; 95% CI: 0.714-0.970) benefit was observed and BMFS was prolonged in all hormone receptor positive patients (HR: 0.850; 95% CI: 0.735-0.983). Fracture incidence (RR: 0.787; 95% CI: 0.696-0.890) and time to first fracture (HR: 0.760; 95% CI: 0.665-0.869) were also improved. No increase in overall toxicity was seen with denosumab and no differences were observed for ONJ and AFF between the 60-mg every 6-month schedule and placebo.

Conclusion

Denosumab addition to anticancer treatment does not improve DFS, BMFS, or OS in the overall population, although a DFS improvement was observed in hormone receptor positive/HER2 negative BC patients and a BMFS improvement in all hormone receptor positive patients. Bone-health outcomes were improved with no added toxicity with the 60-mg schedule.

Registration

PROSPERO identifier: CRD42022332787.

St. Gallen/Vienna 2023: Optimization of Treatment for Patients with Primary Breast Cancer - A Brief Summary of the Consensus Discussion

The St. Gallen Consensus Conference on early breast cancer treatment 2023 was again a live event and took place in Vienna, Austria. After 4 years and one virtual event due to the pandemic, more than 2,800 participants from over 100 countries came together in Vienna, and the 2023 St. Gallen/Vienna conference was a great success. Over 3 days, the global faculty reviewed the most important evidence published during the last 2 years and debated over controversial topics, and finally, the consensus votes aimed to define the impact of the new data on everyday routine practice. Focuses of this year's conference were radiotherapy and local management of the axilla, genetics, and their impact on treatment, as well as the role of the immune system and tumor-infiltrating lymphocytes in pathological reports and treatment decision-making. The traditional panel votes were moderated for the first time by Harold Burstein from Boston, and with questions previously voted on and live voting, the panel managed for the most part to clarify the critical questions. This report by editors of BREAST CARE summarizes the results of the 2023 international panel votes with respect to locoregional and systemic treatment as a brief news update but does not intend to replace the official St. Gallen Consensus publication that not just reports but also interprets the panel votes and will follow shortly in a major oncological journal. The next (19th) St. Gallen International Breast Cancer Conference will again take place in Vienna (save the date: March 12-15, 2025).

Bone modifying agents in postmenopausal breast cancer patients treated with aromatase inhibitors: beyond bone protection?

Estrogen-receptor positive tumours represent the majority of breast cancers in postmenopausal women. Adjuvant endocrine therapy with aromatase inhibitors (AIs), continued for up to 10 years in high-risk patients, reduces by 40% the risk of recurrence. However, this therapy, among other side effects, is burdened with a higher incidence of osteoporotic bone fractures. To date, both bisphosphonates and denosumab are recognized as first-line drugs in the primary prevention of osteoporotic fractures in patients treated with AIs. They have demonstrated their effectiveness in increasing bone mineral density and in reducing the incidence of fractures, but they have also been shown to improve disease free survival (DFS).

Bone-Modifying Agents in Early Breast Cancer: Making Sense of Conflicting Data

The use of adjuvant bone-modifying agents to reduce risk of recurrence in patients with early-stage breast cancer has not been widely embraced because of conflicting data and small absolute benefits. The clinical practice guideline produced jointly by the American Society of Clinical Oncology and Cancer Care Ontario recommends discussion of risks/benefits with postmenopausal patients with early-stage breast cancer about adjuvant bisphosphonates and does not recommend use of adjuvant denosumab to prevent breast cancer recurrence.1.