Management of Aromatase Inhibitor-Associated Bone Loss (AIBL) in postmenopausal women with hormone sensitive breast cancer: Joint position statement of the IOF, CABS, ECTS, IEG, ESCEO IMS, and SIOG

Bone metastasis: mechanisms, therapies, and biomarkers

Skeletal metastases are frequent complications of many cancers, causing bone complications (fractures, bone pain, disability) that negatively affect the patient's quality of life. Here, we first discuss the burden of skeletal complications in cancer bone metastasis. We then describe the pathophysiology of bone metastasis. Bone metastasis is a multistage process: long before the development of clinically detectable metastases, circulating tumor cells settle and enter a dormant state in normal vascular and endosteal niches present in the bone marrow, which provide immediate attachment and shelter, and only become active years later as they proliferate and alter the functions of bone-resorbing (osteoclasts) and bone-forming (osteoblasts) cells, promoting skeletal destruction. The molecular mechanisms involved in mediating each of these steps are described, and we also explain how tumor cells interact with a myriad of interconnected cell populations in the bone marrow, including a rich vascular network, immune cells, adipocytes, and nerves. We discuss metabolic programs that tumor cells could engage with to specifically grow in bone. We also describe the progress and future directions of existing bone-targeted agents and report emerging therapies that have arisen from recent advances in our understanding of the pathophysiology of bone metastases. Finally, we discuss the value of bone turnover biomarkers in detection and monitoring of progression and therapeutic effects in patients with bone metastasis.

Feasibility outcomes of a randomised, multicentre, pilot trial comparing standard 6-monthly dosing of adjuvant zoledronate with a single one-time dose in patients with early stage breast cancer

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Adjuvant bisphosphonates are an established standard in postmenopausal breast cancer.

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Guidelines note the need to explore different agents, doses, and intervals of bisphosphonates.

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Feasibility of randomizing to 6-monthly vs one dose of IV zoledronate was demonstrated.

Background

Adjuvant zoledronate is widely used in patients with early stage breast cancer (EBC), but its optimal duration and dosing interval is still unknown. While a single-dose of zoledronate can improve bone density for many years, a proper evaluation of its effects on breast cancer-related outcomes would require a large trial. In this pilot study we evaluated the feasibility of performing such a trial.

Methods

Eligible patients with EBC were randomised to receive either one dose of zoledronate or 7 doses (6-monthly dosing for 3 years). Feasibility was assessed by a combination of primary outcomes including: activation of at least 6 Ontario sites within a year, active participation (i.e. approaching eligible patients for study participation) of at least half of the medical oncologists, and enrolment of at least 100 patients across all sites within 9 months of the sixth site being activated.

Results

All 6 sites were activated within 1 year and of 47 medical oncologists, 27 (57%) approached patients. Between November 2018 and April 2020, 211 eligible patients were randomised, 106 (50.2%) to a single dose of zoledronate and 105 (49.8%) to 6-monthly dosing. Baseline characteristics of randomised patients included; median age 59 (range 36–88), ER and/or PR positive (85%), Her2 positive (23%), menopausal status (premenopausal [19%], perimenopausal [6.7%] and postmenopausal [74%]) and 74% received neo/adjuvant chemotherapy.

Conclusions

All study feasibility endpoints were met in this trial comparing alternative schedules for adjuvant zoledronate. We will now seek funding for performing a larger efficacy trial.

Trial registration: NCT03664687.

Osteoporotic Fractures of the Spine, Hip, and Other Locations after Adjuvant Endocrine Therapy with Aromatase Inhibitors in Breast Cancer Patients: a Meta-analysis

BACKGROUND

Aromatase inhibitors (AIs) play an important role in the endocrine therapy of postmenopausal breast cancer patients, with a recent tendency to extend the duration of their use. However, AIs may increase the risk of osteoporotic bone fractures. This meta-analysis evaluated the risk of osteoporotic fractures of the hip, spine, and other locations in breast cancer patients using AIs.

METHODS

We performed a systematic search to identify randomized controlled clinical trials that investigated osteoporotic fractures in breast cancer patients on AI therapy. The main outcomes were the incidence and risk of osteoporotic fractures in general and of hip, vertebral, and non-vertebral fractures in AI users and controls.

RESULTS

The systematic review found a total of 30 randomized controlled trials including 117,974 participants. The meta-analysis showed a higher incidence of osteoporotic fracture in AI users: The crude risk ratio for all osteoporotic fractures was 1.35 (95% confidence interval [CI], 1.29-1.42; P < 0.001), for hip fractures 1.18 (95% CI, 1.02-1.35; P < 0.001), for vertebral fractures 1.84 (95% CI, 1.36-2.49; P < 0.001), and for non-vertebral fractures 1.18 (95% CI, 1.02-1.35; P < 0.001), respectively, compared to the controls.

CONCLUSION

Our meta-analysis suggested an increased risk of osteoporotic fractures for AI therapy in patients with breast cancer that was most expressed for vertebral fractures. Breast cancer patients on AIs need to be monitored for osteoporosis and osteoporotic fractures, and active prevention measures should be implemented.

Effect of Denosumab on Glucose Homeostasis in Postmenopausal Women with Breast Cancer Treated with Aromatase Inhibitors: A Pilot Study

BACKGROUND

Aromatase inhibitors in women with breast cancer have been associated with cancer treatment-induced bone loss (CTIBL), increased fracture risk, and impairment of glucose metabolism. Denosumab (Dmab), a monoclonal antibody against RANKL, which is a key regulator of the osteoclast activity, is effective as an antiresorptive agent in the treatment of CTIBL. Since RANKL/RANK pathway may contribute to the pathogenesis of glucometabolic disorders, it has been suggested that Dmab may improve glucose homeostasis. Our pilot study evaluated the effect of a single administration of 60 mg Dmab on glucose metabolism in a cohort of women with breast cancer treated with aromatase inhibitors.

METHODS

Fifteen postmenopausal nondiabetic women were prospectively enrolled. Oral glucose tolerance test (OGTT) and metabolic parameters, including FGF21, were assessed at baseline and one month after Dmab injection. Midterm glucose control was evaluated by measuring glycated haemoglobin (HbA1c) levels 5 months after Dmab.

RESULTS

Parameters of glucose metabolism were not different one month after Dmab but circulating FGF21 levels significantly decreased (128.5 ± 46.8 versus 100.2 ± 48.8 pg/mL; p=0.016). Considering patients with insulin resistance at baseline (HOMA-IR > 2.5 and Matsuda Index < 2.5; n = 5), reduced mean fasting insulin levels (16.3 ± 4.9 versus 13.5 ± 3.5 mcU/mL; p=0.029) and increased insulin sensitivity index QUICKI (0.317 ± 0.013 versus 0.327 ± 0.009; p=0.025) were found. Nonetheless, HbA1c increased 5 months after Dmab (36.0 ± 2.3 versus 39.6 ± 3.1 mmol/mol; p=0.01).

CONCLUSIONS

Although RANKL blockade induced a short-term positive effect on insulin sensitivity, particularly in insulin-resistant patients, a benefit on long-term glucose metabolism was not evident. In conclusion, Dmab is safe for glucose metabolism in aromatase inhibitor-treated women with breast cancer.

Osteoporosis: A Long-Term and Late-Effect of Breast Cancer Treatments

Simple Summary

Osteoporosis is a prevalent condition affecting 200 million individuals world-wide. Estimates are about one in three women will experience a fragility fracture of hip, spine or wrist. Common breast cancer treatments, such as aromatase inhibitors in postmenopausal women and chemotherapy-induced ovarian failure in premenopausal women, cause bone loss that in some women will lead to osteoporosis and fragility fractures. Fragility fractures cause morbidity and mortality and are entirely preventable. Prevention or treatment of osteoporosis includes lifestyle modifications (e.g., reducing smoking and excessive alcohol consumption, and increasing physical activity), taking calcium and vitamin D3, screening for osteoporosis with dual-energy absorptiometry, and treatment, if clinically indicated, with ether oral bisphosphonates, intravenous zoledronic acid, or subcutaneous denosumab. This chapter reviews the pathogenesis of osteoporosis, the magnitude of bone loss related to common breast cancer treatments, osteoporosis risk factor assessment and screening, and the specific drugs to treat or prevent osteoporosis.

Abstract

Osteoporosis is both a long-term effect (occurs during treatment and extends after treatment) and a late-effect (occurs after treatment ends) of breast cancer treatments. The worldwide prevalence of osteoporosis is estimated to be some 200 million patients. About one in three postmenopausal women will experience an osteoporotic (or fragility) fracture of the hip, spine, or wrist. breast cancer treatments, including gonadotropin-releasing hormone (GnRH) agonists, chemotherapy-induced ovarian failure (CIOF), and aromatase inhibitors (AIs), cause bone loss and increase the risks of osteoporosis. Also, breast cancer is a disease of aging, and most of the “one in eight” lifetime risks of breast cancer are in women in their sixth, seventh, and eighth decades. The majority of women diagnosed with breast cancers today will be long-term survivors and experience personal cures. It is the coalescence of osteoporosis with breast cancer, two common and age-related conditions that make osteoporosis relevant in women with breast cancer throughout the continuum from diagnosis, treatment, and survivorship. It is critical to remember that women (and men) will lose bone after age thirty years. However, only certain women will lose bone of sufficient magnitude to merit treatment with anti-osteoporosis drugs. The narrative review is intended for medical, surgical, radiation oncologists, and other mid-level providers, and provides an overview of bone loss and the prevention and treatment of osteoporosis.

Factors Associated With Bone Density Monitoring While on Antiosteoporosis Treatment in Routine Clinical Practice: A Registry-Based Cohort Study

The role for bone mineral density (BMD) monitoring while on antiosteoporosis therapy remains controversial. The current study used population-based registries to identify factors associated with BMD monitoring in women within 5 yr of receiving antiosteoporosis treatment vs treatment without monitoring in routine clinical practice. The analytical dataset consisted of women age 40 yr and older at baseline receiving antiosteoporosis therapy: 6877 with BMD monitoring (mean interval 3.2 yr) and 6747 without BMD monitoring. There was a significant negative secular trend in BMD monitoring during the study period (p < 0.001). Multivariable logistic regression demonstrated that parental hip fracture, glucocorticoid and aromatase inhibitor use, and lower baseline BMD were independently and positively associated with BMD monitoring. Individuals with increasing age, greater body mass index, smoking, rheumatoid arthritis, later calendar year, diabetes, rural residency, lower income, and greater comorbidity score were less likely to undergo monitoring. A shorter monitoring interval (<23 mo) was strongly associated with glucocorticoid and aromatase inhibitor use. In conclusion, our study identifies factors associated with BMD monitoring over 5 yr in patients receiving antiosteoporosis therapy.

Challenges in Preventing Bone Loss Induced by Aromatase Inhibitors

CONTEXT

Aromatase inhibitors have become a mainstay in the adjuvant treatment regimen in postmenopausal women with hormone receptor-positive breast cancer. While many of these patients have an excellent long-term prognosis, adverse effects on bone represent an emerging complication of aromatase inhibitor treatment, resulting in substantial bone loss and fragility fractures. Treatment approaches to prevent aromatase inhibitor-induced bone loss typically consist of an antiresorptive approach with bisphosphonates or the RANKL antibody denosumab. However, different guidelines vary with respect to treatment thresholds, duration, and dosing. The choice of antiresorptive regime is further complicated by comorbidities and potential disease-modifying effects of individual agents.

OBJECTIVE

This review summarizes the evidence of how aromatase inhibitors affect bone health and provides an update of clinical approaches to preserve bone strength in affected women. (J Clin Endocrinol Metab XX: 0-0, 2020).

Denosumab for cancer-related bone loss

INTRODUCTION

Prolonged use of anti-cancer treatments in breast and prostate tumors alters physiological bone turnover leading to adverse skeletal related events, such as osteoporosis, loss of bone mass, and increased risk of fractures. These complications known as cancer treatment-induced bone loss (CTIBL) should be managed with bone targeting agents such as the bisphosphonates and denosumab. The latter is a monoclonal antibody against the receptor activator of nuclear factor-kB ligand (RANKL) that suppresses osteoclasts function and survival increasing bone mass.

AREAS COVERED

This review will focus on the mechanisms associated with bone loss induced by cancer treatments and the most recent evidence about the use of denosumab as preventive and therapeutic strategy to protect bone health. Moreover, we will discuss several key aspects regarding the clinical practical use of denosumab to optimize the management of CTLIB in breast and prostate cancer.

EXPERT OPINION

Denosumab treatment strongly prevents cancer therapies-related skeletal issues in breast and prostate cancer with a good safety profile. Adjuvant six-monthly denosumab delays the time to first fracture onset in early stage breast cancer patients with normal or altered bone mineral density (BMD). Similarly, denosumab treatment is able to prevent fractures and BMD loss in nonmetastatic prostate cancer patients.

Aromatase Inhibitors-Induced Musculoskeletal Disorders: Current Knowledge on Clinical and Molecular Aspects

Aromatase inhibitors (AIs) have radically changed the prognosis of hormone receptor positive breast cancer (BC) in post-menopausal women, and are a mainstay of the adjuvant therapy for BC after surgery in place of, or following, Tamoxifen. However, AIs aren't side effect-free; frequent adverse events involve the musculoskeletal system, in the form of bone loss, AI-associated arthralgia (AIA) syndrome and autoimmune rheumatic diseases. In this narrative review, we reported the main clinical features of these three detrimental conditions, their influence on therapy adherence, the possible underlying molecular mechanisms and the available pharmacological and non-pharmacological treatments. The best-known form is the AIs-induced osteoporosis, whose molecular pathway and therapeutic possibilities were extensively investigated in the last decade. AIA syndrome is a high prevalent joint pain disorder which often determines a premature discontinuation of the therapy. Several points still need to be clarified, as a universally accepted diagnostic definition, the pathogenetic mechanisms and satisfactory management strategies. The association of AIs therapy with autoimmune diseases is of the utmost interest. The related literature has been recently expanded, but many issues remain to be explored, the first being the molecular mechanisms.

Management of hormone receptor-positive, HER2-negative early breast cancer

The majority of breast cancers are diagnosed at an early stage and are hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative. Significant advances have been made in the management of early stage HR-positive, HER2-negative breast cancer, resulting in improved survival outcomes. In this review, we discuss important factors to consider in the management of this disease. In particular, we discuss the role of adjuvant endocrine therapy, specific endocrine therapy agents, the duration of adjuvant endocrine therapy, treatment-related side effects, and the role of genomic assays and other biomarkers when considering treatment recommendations for individuals with HR-positive, HER2-negative early breast cancer. Finally, we address emerging data to individualize therapeutic decision-making and provide future considerations.

Bone health care in women with breast cancer

The aim of this article is to analyze and critically appraise the literature regarding optimal bone health care in women with breast cancer and, more specifically, to present (1) the causes of bone loss in breast cancer patients, (2) the appropriate screening for osteoporosis and fracture risk estimation, (3) optimal prevention and therapeutic strategies for osteoporosis and fractures, (4) the role of antiresorptive agents as adjuvant therapy for the prevention of bone metastases and increase of overall survival, and (5) current data on the possible use of menopausal hormone therapy (MHT) in these patients. The objective is to provide a sound pathophysiological background along with evidence-based and practical recommendations for physicians managing such women.

Management of osteoporosis in women with breast cancer

The screening, prevention and treatment of osteoporosis are similar in women with or without breast cancer. Breast cancer treatments, such as aromatase inhibitors, chemotherapy-induced ovarian failure and gonadotropin-releasing hormone antagonists all decrease estrogen levels, which in turn causes net bone resorption and bone loss. Bone loss over time will be of sufficient magnitude to cause some women to experience fractures. Thus, osteoporosis is an equation; the peak bone mass achieved by age 30 years minus the age-related and menopausal bone loss. Women should have their bone density measured by dual x-ray absorptiometry scans every 2 years. As clinically indicated, women should receive anti-osteoporosis drugs such as zoledronic acid, denosumab or oral bisphosphonates.

Practical Vitamin D Supplementation Using Machine Learning

Background

Patients with breast cancer are at increased risk of developing osteoporosis. Maintaining normal levels of vitamin D may decrease the risk of osteoporosis, and vitamin D levels must be corrected in patients who develop osteoporosis before beginning bone modifying agents. Therefore, it is important to correct insufficient vitamin D levels in a timely manner. In clinical practice, current guidelines for replacement regimens often fail to rapidly correct vitamin D levels. The goal of this study was to review data in order to predict what replacement regimen(s) were most effective at repleting vitamin D levels.

Methods

For this retrospective cohort study, data was collected from medical records of 2,164 female patients with breast cancer with Institutional Review Board approval. Total level change per week was the primary outcome and was compared for the most commonly used vitamin D replacement regimens adjusted for age, race, body mass index, creatinine clearance, endocrine therapy, and initial level.

Results

Higher weekly doses of vitamin D supplementation had a more significant impact on the rate of correction compared to lower daily doses. Generalized linear model was used to develop an online calculator that predicts time to vitamin D level correction adjusted for significant patient characteristics for 5 common replacement regimens as well as no intervention.

Conclusions

When choosing a vitamin D replacement regimen for patients with vitamin D deficiency, we recommend clinicians use the online calculator to ensure that the chosen regimen will enable the patient to reach vitamin D sufficiency in a timely manner.

Clinical benefits of bone targeted agents in early breast cancer

Through their profound effects on the bone microenvironment, bone targeted treatments can potentially modify the process of metastasis and have important effects on disease outcomes as well as on bone health. The Early Breast Cancer Trialists Collaborative Group (EBCTCG) evaluated the effect of adjuvant bisphosphonates in early breast cancer by performing a meta-analysis of individual patient data (n = 18,766) from all available randomized trials initiated between the early 1990s until 2006. In postmenopausal women, bisphosphonates reduced bone recurrence (RR = 0.72; 95%CI 0.60-0.86, 2p = 0.0002) and breast cancer mortality (0.82; 95%CI 0.73-0.93, 2p = 0.002); no effects on disease outcomes could be identified in premenopausal women. Somewhat surprisingly, these effects could not be reproduced in the large adjuvant trial of denosumab (DCARE). In this study, neither bone metastasis free survival (the primary endpoint) or disease-free survival were improved by the addition of this targeted antibody inhibitor of osteoclast activity. Efforts are ongoing to try to understand the biologic implications of these results. For now, the use of denosumab in early cancers is limited to its use for fracture prevention using the 60mg every 6 months dosing schedule.

Bone modifying agents for bone loss in patients with aromatase inhibitor as adjuvant treatment for breast cancer; insights from a network meta-analysis

PURPOSE

The data of head-to-head comparisons of the anti-fracture efficacy of bone modifying agents (BMAs) in patients with hormone receptor-positive breast cancer receiving aromatase inhibitor (AI) are not available. Therefore, we conducted a network meta-analysis to compare the efficacy of different BMAs in patients with breast cancer receiving adjuvant AI.

METHODS

We performed a network meta-analysis to compare the change of bone mineral densities (BMDs) and the risk of fracture in the selected studies using a random effect model. The primary outcomes are the change of BMD of lumbar spine (LS) and total hip (TH) from the baseline (ΔBMD, %) at 1 and 2 years and the risk of fracture.

RESULTS

We identified and included a total of 16 randomized controlled trials for this analysis. All BMAs included (risedronate, zoledronate, and denosumab) were associated with a significant increase in BMD of LS and TH at 1 and 2 years compared with no upfront treatment group. Among BMAs, zoledronate and denosumab use resulted in significantly higher BMD of LS and TH at 1 and 2 years compared with risedronate. The risk of fracture was significantly lower in the patients who received denosumab or risedronate compared with the patients without upfront treatment (Relative risk (RR) [95% CI] 0.51 [0.38-0.67] and 0.54 [0.35-0.83], respectively).

CONCLUSION

Among the bisphosphonates, zoledronate increased BMD the most, but risedronate, not zoledronate, use was associated with lower risk of fracture. Denosumab increased BMD not only of LS but also of the cortical-bone-rich hip, and showed a significant reduction of fracture risk.

Effect of Tamoxifen on the Risk of Osteoporosis and Osteoporotic Fracture in Younger Breast Cancer Survivors: A Nationwide Study

Background: Although international guidelines recommend bone screening for premenopausal breast cancer patients taking adjuvant tamoxifen, the effects of tamoxifen on osteoporosis and related risks remain controversial. The objective of this study was to investigate the incidence of and risk factors for osteoporosis and osteoporotic fractures in younger breast cancer patients.

Methods: A nationwide retrospective cohort study was conducted using South Korea Health Insurance Review and Assessment Service claims data. The rates of osteoporosis and osteoporotic fracture were calculated as incident cases per person-year and disease-free probability rates were analyzed with the Kaplan-Meier method. To identify risk factors for osteoporosis and osteoporotic fracture, a multivariable Cox proportional hazard regression model was applied.

Results: From January 2009 to December 2014, a total of 47,649 breast cancer patients were included. The incidence rates of osteoporosis and osteoporotic fracture were 23.59 and 2.40 per 1,000 person-years, respectively. In the overall population, tamoxifen was significantly associated with a decreased risk of osteoporosis and osteoporotic fractures 0.76). However, tamoxifen was not associated with the risk of osteoporosis (HR 1.24, CI 0.85–1.82) and osteoporotic fracture (HR 8.15, CI 0.36–186.70) in patients under age 40. In the 40–49 years subgroup, tamoxifen significantly decreased the risk of osteoporosis (HR 0.74, CI 0.65–0.84) and osteoporotic fracture (HR 0.49, CI 0.31–0.76).

Conclusions: Tamoxifen is not associated with an increased risk of osteoporosis and osteoporotic fracture in premenopausal breast cancer patients. Tailored screening strategies for breast cancer survivors with different osteoporosis risks are needed.

Precis: Tamoxifen is not associated with an increased risk of osteoporosis and osteoporotic fracture in premenopausal breast cancer patients. Tailored screening strategies for breast cancer survivors who are at different risks of developing osteoporosis are needed.

Evaluation of appropriate use of bisphosphonates and denosumab in patients with cancer

Background

National guidelines recommend screening and treatment for cancer-related bone disease and continued monitoring of bone-modifying agents. It is unclear whether a standardized screening tool is utilized to identify eligible patients and ensure appropriate supportive care is implemented. The purpose of this study was to evaluate current prescribing practices and optimize management of bone-modifying agents.

Methods

A retrospective chart review was performed to identify patients who received hormone deprivation therapy or had bone metastases through Hematology/Oncology or Urology clinics from 1 November 2016 to 31 October 2017. The primary endpoints of this study were the incidence of completed baseline dual-energy X-ray absorptiometry (DEXA) scan for patients on hormone deprivation therapy and percent of patients started on a bone-modifying agent for the prevention of skeletal-related events secondary to bone metastasis. Secondary endpoints included percent of patients with dental examinations prior to initiation, adequate calcium and vitamin D supplementation, incidence of osteonecrosis of the jaw or flu-like symptoms and education, and percent of bisphosphonate doses appropriately adjusted based on renal function.

Results

A total of 375 patients were assessed for baseline DEXA scans and bone-modifying therapy. Of the 226 patients on hormone deprivation therapy, 111 (49%) patients were appropriately screened with a DEXA scan prior to initiation of hormone deprivation therapy. Among the 149 patients with bone metastases, only 94 (63.1%) patients were started on a bone-modifying agent.

Conclusions

Opportunities have been identified to optimize management of patients with cancer-related bone disease. Implementation of standardized tools may increase the rate of appropriate screening and initiation of bone-modifying therapy when warranted.

Management manual for cancer treatment-induced bone loss (CTIBL): position statement of the JSBMR

Androgen deprivation therapy and aromatase inhibitors are known to cause a decrease in bone mineral density and an increase in fractures. Patients receiving these treatments have been shown to have a fracture risk equal to or greater than that of patients with osteoporosis with prevalent fractures. This manual was created to prevent fractures in patients with cancer treatment-induced bone loss with high fracture risks who cannot be treated under the current Japanese guideline for the prevention and treatment of osteoporosis. This manual recommends drug treatment for patients with BMD - 2.0 ≤ T score < - 1.5 with the family history of hip fracture or 15% or more 10-year probability of major osteoporotic fractures by FRAX^®; or in patients with BMD T score < - 2.0. It is important to verify whether the use of this manual can reduce fractures and improve the quality of life of patients with cancer treatment-induced bone loss by prospective studies.

Endocrine Therapy-related Endocrinopathies-Biology, Prevalence and Implications for the Management of Breast Cancer

Nearly 270,000 new breast cancer cases are predicted to be diagnosed in the USA in 2019 with more than 70% being estrogen receptor positive and treated using endocrine therapy. The suppression of estrogen biosynthesis or action via the use of ovarian suppression, aromatase inhibitors and selective estrogen receptor modulators/degraders, respectively, is effective in approximately 70% of women. The systemic inhibition of estrogen during breast cancer treatment is also associated with side effects due to the important endocrine functions of this steroid hormone, including its role in the maintenance of energy homeostasis and bone health. The current work will present perspectives of the impact of endocrine therapy from the point of view of breast medical oncology, endocrinology, and basic science.

Increased Fracture Risk in Women Treated With Aromatase Inhibitors Versus Tamoxifen: Beneficial Effect of Bisphosphonates

Aromatase inhibitors have been associated with accelerated bone loss and an increased risk of osteoporotic fractures. Currently, bisphosphonates are recommended to reduce fracture risk in these patients. The aim of this study is to evaluate the fracture risk in breast cancer patients receiving aromatase inhibitors, compared to tamoxifen users, and to assess the effectiveness of oral bisphosphonates in reducing fracture risk. We performed an observational cohort study up to 10 years of follow-up. Data were extracted from primary care records in a population database. Women diagnosed with breast cancer between 2006 and 2015 and treated with tamoxifen or aromatase inhibitors (n = 36,472) were stratified according to low (without osteoporosis diagnosis nor bisphosphonates exposure) or high (with osteoporosis and/or treated with bisphosphonates) fracture risk. Cox models were used to calculate hazard ratios (HR [95% CI]) of fracture from the propensity score-matched patients. Sensitivity analyses account for competing risk of death were performed (subdistribution hazard ratio [SHR] [95% CI]). In postmenopausal women, fracture risk in aromatase inhibitor users showed an HR 1.40 [95% CI,1.05 to 1.87] and SHR 1.48 [95% CI, 1.11 to 1.98], compared to tamoxifen. Observing aromatase inhibitors patients at high risk of fracture, bisphosphonate-treated patients had an HR 0.73 [95% CI, 0.51 to 1.04] and SHR 0.69 [95% CI, 0.48 to 0.98] compared to nontreated. In conclusion, fracture risk in postmenopausal women during aromatase inhibitor treatment, in real-life conditions, was >40% compared to tamoxifen, corroborating previous randomized controlled trials results. In high-risk patients, bisphosphonate users had lower significant fracture incidence during aromatase inhibitor therapy than nonbisphosphonate users. Monitoring fracture risk and related risk factors in aromatase inhibitor patients is advisable. © 2019 American Society for Bone and Mineral Research.

Proceedings of the 2019 Santa Fe Bone Symposium: New Concepts in the Care of Osteoporosis and Rare Bone Diseases

The 20th annual Santa Fe Bone Symposium was held August 9-10, 2019, in Santa Fe, New Mexico, USA. This is an annual meeting devoted to clinical applications of recent advances in skeletal research that impact the care of patients with osteoporosis, metabolic bone diseases, and inherited bone diseases. Participants included practicing and academic physicians, fellows, advanced practice providers, fracture liaison service (FLS) coordinators, clinical researchers, and bone density technologists. The symposium consisted of lectures, case presentations, and panel discussions, with an emphasis on learning through interaction of all attendees. Topics included new approaches in the use of anabolic agents for the treatment osteoporosis, a review of important events in skeletal health over the past year, new and emerging treatments for rare bone diseases, the use of genetic testing for bone diseases in clinical practice, medication-associated causes of osteoporosis, new concepts in the use of estrogen therapy for osteoporosis, new Official Positions of the International Society for Clinical Densitometry, skeletal consequences of bariatric surgery, and update on the progress and potential of Bone Health TeleECHO, a virtual community of practice using videoconferencing technology to link healthcare professionals for advancing the care of osteoporosis worldwide. Sessions on rare bone diseases were developed in collaboration with the Rare Bone Disease Alliance. Symposium premeetings included an FLS workshop by the National Osteoporosis Foundation and others devoted to the use of new therapeutic agents for the care of osteoporosis and related disorders.

Evaluation of baseline fracture risk in younger postmenopausal women with breast cancer using different risk assessment methods

OBJECTIVE

Controversy exists about the impact of bone mineral density (BMD) and fracture risk in newly diagnosed patients with breast cancer (BC). It is presumed that there are differences in BMD between women with BC and healthy controls. BMD is therefore considered as a potential marker to predict BC risk. This study was conducted to investigate the association of BMD, trabecular bone score (TBS) and fracture risk in younger postmenopausal women with hormone responsive BC.

METHODS

Overall, 343 women were examined. Women with BC were matched to a control group of the general population. Forty-nine women and fifty-nine controls were included in the final analysis. All subjects underwent dual energy x-ray absorptiometry (DXA) of the lumbar spine, femoral neck, and the total hip to evaluate bone mineral density. The 10-year fracture risk for a major osteoporotic fracture was assessed using the FRAX-score and the TBS-adjusted FRAX-Score, respectively.

RESULTS

Lumbar and femoral neck BMD were similar in BC patients and controls. No difference was found for TBS of the spine (1.38 ± 0.1 vs.1.36 ± 0.09) in the BC and the control group, respectively (p = 0.19). The 10- year probability for a major osteoporotic fracture (MoF) or femoral neck (FN) fracture was 6.1 (± 2.6%) and 0.9 (± 1.2%) in the BC group vs. 6.7 (± 3.5%) (p = 0.33) and 0.9 (± 1.1%) (p = 0.73) in the control group.

CONCLUSION

Postmenopausal women younger than 60 years with breast cancer do not show any differences in baseline BMD, TBS, or TBS adjusted FRAX in comparison to controls.

BOne HEalth ManagEment in Patients with Early Breast Cancer: A Retrospective Italian Osteoncology Center "Real-Life" Experience (BOHEME Study)

Background: We assessed the real-life clinical impact of bone health management in patients with breast cancer (BC) receiving adjuvant endocrine therapy at an Italian Osteoncology Center. Methods: Pre- and post-menopausal women undergoing adjuvant endocrine therapy for early-stage BC who came to our institute for their first bone health evaluation from January 2011 to June 2016 were considered in this retrospective observational study. Results: 1125 pre- and post-menopausal early-stage BC patients (209 and 916, respectively) were evaluated. Median age was 61 years (range 26–88). In the pre-menopausal group, spinal x-ray revealed that 10 patients (4.7%) had a morphometric vertebral fracture. Higher age (OR: 1.14; 95% CI: 1.01–1.29) and bone mineral density (BMD) ≤ −2.5 (OR: 14.45; 95% CI: 1.70–122.67) were associated with a higher risk of bone fracture. The overall frequency of bone fracture was 17.6% (n = 161) in post-menopausal patients and a lower risk for bone fractures was associated with tamoxifen or other treatments (OR: 0.25; 95% CI: 0.12–0.53), presence of back pain (OR: 1.65; 95% CI: 1.16–2.36), lower BMD (OR: 2.09 in patients with T-score ≤ 2.5; 95% CI: 1.21–3.59) and lower vitamin D levels (OR: 1.57 in patients with ≤ 10 ng/mL; 95% CI: 1.05–2.34) in univariate analysis. Conclusion: Our findings confirm that bone health management should be an integral part of long-term cancer care.

Management of Osteoporosis in Survivors of Adult Cancers With Nonmetastatic Disease: ASCO Clinical Practice Guideline

PURPOSE

The aim of this work is to provide evidence-based guidance on the management of osteoporosis in survivors of adult cancer.

METHODS

ASCO convened a multidisciplinary Expert Panel to develop guideline recommendations based on a systematic review of the literature.

RESULTS

The literature search of the 2018 systematic review by the US Preventive Services Task Force in the noncancer population was used as the evidentiary base upon which the Expert Panel based many of its recommendations. A total of 61 additional studies on topics and populations not covered in the US Preventive Services Task Force review were also included. Patients with cancer with metastatic disease and cancer survival outcomes related to bone-modifying agents are not included in this guideline.

RECOMMENDATIONS

Patients with nonmetastatic cancer may be at risk for osteoporotic fractures due to baseline risks or due to the added risks that are associated with their cancer therapy. Clinicians are advised to assess fracture risk using established tools. For those patients with substantial risk of osteoporotic fracture, the clinician should obtain a bone mineral density test. The bone health of all patients may benefit from optimizing nutrition, exercise, and lifestyle. When a pharmacologic agent is indicated, bisphosphonates or denosumab at osteoporosis-indicated dosages are the preferred interventions.

Trabecular bone score and quantitative ultrasound measurements in the assessment of bone health in breast cancer survivors assuming aromatase inhibitors

PURPOSE

Aromatase inhibitors (AIs) represent the first-line adjuvant therapy for hormone receptor-positive breast cancer (BC) women. AIs have been associated with an increased rate of fractures. The aim of our study was to investigate trabecular bone score (TBS) and bone quantitative ultrasound (QUS) measurements as bone quality surrogates in AIs users.

METHODS

Sixty postmenopausal BC women starting AIs and forty-two controls (mean age 61.64 ± 8.33 years) were considered. Bone mineral density (BMD) at lumbar spine and femoral neck and TBS were measured by DXA; QUS-derived Amplitude-Dependent Speed of Sound (AD-SoS), Bone Transmission Time (BTT), and Ultrasound Bone Profile Index (UBPI) were assessed at phalangeal site; morphometric vertebral fractures (Vfx) by X-ray, serum bone-specific alkaline phosphatase (BSAP), and C-telopeptide of type 1 collagen (CTX) were also evaluated.

RESULTS

After 18 months, changes of TBS vs baseline were significantly different between AIs group and controls [Δ TBS - 2.2% vs - 0.4%, respectively, p = 0.001]. AD-SoS, BTT and UBPI values decreased only in AIs' group (- 3.7%, - 6.45%, -8.5%, vs baseline, respectively, p_all < 0.001). 3 Vfx occurred in AIs users and were associated with the greater TBS and AD-SoS modifications. In the AIs' group, ΔTBS was associated with ΔAD-SoS (r = 0.58, p < 0.001) and ΔUBPI (r = 0.415, p = 0.001), but not with ΔBMD. Moreover, ΔTBS was independently predicted by ΔAD-SoS, after correcting for BMD, CTX and BSAP level changes (β = 0.37, SE = 2.44, p < 0.001).

CONCLUSIONS

TBS and phalangeal QUS provide useful information related to bone quality in AI-treated BC survivors and could be considered for fracture risk evaluation.

Sixty spontaneous vertebral fractures after denosumab discontinuation in 15 women with early-stage breast cancer under aromatase inhibitors

PURPOSE

At denosumab discontinuation, bone turnover markers increase and the gained BMD is lost. In postmenopausal osteoporosis, there is an increased risk of spontaneous vertebral fractures (VFs) of about 1 to 10%, rarely described in women under denosumab for aromatase inhibitors (AI)-treated breast cancer. We aim to describe the characteristics of 15 patients under denosumab given for AI-treated early-stage breast cancer that presented VFs at its discontinuation.

METHODS

Single-center retrospective case series of 15 patients. We report clinical data, dual X-ray absorptiometry values at denosumab initiation and discontinuation, and serum B-crosslaps dosage at the time of VF occurrence (before denosumab resumption).

RESULTS

Fifteen women (66.4 ± 7.1 years at denosumab discontinuation) that received AI for 5.0 ± 0.6 years, denosumab 60 mg for 8.2 ± 2.0 doses, and developed 60 VFs at denosumab discontinuation, were followed for 24.4 ± 9.5 months. Patients suffered from 1 to 11 (mean 4.0 ± 1.9) clinical VFs within 7 to 16 months after last denosumab injection. VFs developed earlier in patients with longer denosumab treatment (R² = 0.29, p = 0.04) and in patients without osteoporosis before denosumab (9.4 ± 2.0 vs. 13.0 ± 2.0 months; p = 0.005). Serum B-crosslaps at the time of VFs tended to be higher in patients with earlier VFs (R² = 0.47; p = 0.06) or with longer denosumab treatment (R² = 0.48; p = 0.06). Denosumab was resumed in all patients, then switched for a bisphosphonate in eight. No new VFs occurred during follow-up.

CONCLUSIONS

Despite an apparently low fracture risk, women under denosumab for AI-treated early-stage breast cancer develop spontaneous VFs at denosumab discontinuation. This risk increases with treatment duration and may be prevented by a potent bisphosphonate.

Calcitriol Analogues Decrease Lung Metastasis but Impair Bone Metabolism in Aged Ovariectomized Mice Bearing 4T1 Mammary Gland Tumours

Calcitriol and its analogues are considered drugs supporting the anticancer treatment of breast cancer and preventing the osteoporosis that results from the development of cancer or from chemotherapy or hormone therapy. Following the orthotopic implantation of 4T1 mammary carcinoma cells into aged ovariectomized (OVX) mice, we evaluated the effects of calcitriol and its two analogues, PRI-2191 and PRI-2205, on metastatic spread and bone homeostasis. Calcitriol and its analogues temporarily inhibited the formation of metastases in the lungs. Unexpectedly, only mice treated with calcitriol analogues showed a deterioration of bone-related parameters, such as bone column density, marrow column density and the CaPO₄ coefficient. These findings correlated with an increased number of active osteoclasts differentiated from bone marrow-derived macrophages in mice treated with the analogues. Interestingly, in the tumours from mice treated with PRI-2191 and PRI-2205, the expression of Tnfsf11 (RANKL) was increased. On the other hand, osteopontin (OPN) levels in plasma and tumour tissue, as well as TRAC5b levels in tumours, were diminished by calcitriol and its analogues. Despite a similar action of both analogues towards bone metabolism, their impact on vitamin D metabolism differed. In particular, PRI-2191 and calcitriol, not PRI-2205 treatment significantly diminished the levels of both 25(OH)D₃ and 24,25(OH)₂D₃. In conclusion, though there is evident antimetastatic activity in old OVX mice, signs of increased bone metabolism and deterioration of bone mineralization during therapy with calcitriol analogues were observed.

Association of Fat Body Mass With Vertebral Fractures in Postmenopausal Women With Early Breast Cancer Undergoing Adjuvant Aromatase Inhibitor Therapy

IMPORTANCE

Aromatase inhibitors induce a profound depletion in serum estrogen levels. Postmenopausal obese women receiving aromatase inhibitor therapy may be at increased risk of bone fractures owing to the detrimental association of adiposity with bone quality and the loss of the protective effect of estrogens on bone mineral density.

OBJECTIVE

To determine whether fat body mass (FBM), as measured by dual-energy x-ray absorptiometry, is associated with vertebral fracture prevalence in postmenopausal women undergoing adjuvant aromatase inhibitor therapy for breast cancer.

DESIGN, SETTING, AND PARTICIPANTS

In this single-center, cross-sectional study, 556 postmenopausal women with early-stage breast cancer were consecutively enrolled from October 15, 2013, to June 30, 2018, and stratified according to whether they were aromatase inhibitor-naive or aromatase inhibitor-treated for at least 2 years. The database was locked on December 31, 2018, and data analysis was completed on February 28, 2019. Eligible patients in both groups had normal renal function, no metabolic diseases, and no previous or current treatment with antiosteoporotic drugs or glucocorticoids. Previous chemotherapy, but not tamoxifen, was permitted. Data were gathered once, at baseline.

MAIN OUTCOMES AND MEASURES

Vertebral fracture prevalence associated with FBM in aromatase inhibitor-naive and aromatase inhibitor-treated patients.

RESULTS

Of the 556 women enrolled, the mean age was 63.0 years (95% CI, 62.2-63.8 years). The 195 aromatase inhibitor-treated patients were older than the 361 aromatase inhibitor-naive patients (mean age, 66.1 vs 61.3 years; P < .001), had a higher body mass index (mean, 26.4 vs 25.3; P = .009), were less likely to engage in physical activity (65.3% vs 73.7%; P = .03), and were less likely to consume alcoholic beverages (68.4% vs 80.9%; P = .001). Among the aromatase inhibitor-naive patients, the vertebral fracture prevalence was higher in the subgroup with FBM below the median value than in those with high FBM, but the difference was not statistically significant (19.2% vs 13.3%; P = .13). Conversely, the proportion of vertebral fractures in the aromatase inhibitor-treated group was 20.0% in patients with low FBM vs 33.3% in patients with high FBM (P = .04). An opposite trend in the association of FBM with vertebral fracture prevalence according to aromatase inhibitor group was shown by multivariable analysis in the propensity score-matched sample: odds ratio, 0.38 (95% CI, 0.12-1.19) and 1.94 (95% CI, 0.67-5.64) in the aromatase inhibitor-naive and aromatase inhibitor-treated groups, respectively (odds ratio for the interaction, 5.77 [95% CI, 1.08-30.81]; P for interaction term = .03).

CONCLUSIONS AND RELEVANCE

Fat body mass may be associated with fragility-related fractures in patients with breast cancer who undergo aromatase inhibitor therapy. If these data are confirmed, obesity could be included in the algorithm for assessing fracture risk and selecting patients to receive bone resorption inhibitors.

Predictive factors for the efficacy of denosumab in postmenopausal Japanese women with non-metastatic breast cancer receiving adjuvant aromatase inhibitors: a combined analysis of two prospective clinical trials

Aromatase inhibitors (AIs) are the gold standard therapy for breast cancer in postmenopausal women. AI suppresses the conversion of androgens to estrogens; however, this results in osteopenia, osteoporosis, and bone fracture, thus reducing the patient's quality of life. The use of adjuvant denosumab reduces the risk of clinical fractures in postmenopausal patients with breast cancer receiving AI. However, the efficacy of denosumab in the treatment of AI-associated bone loss has not been prospectively evaluated in Japan. In this study, we aimed to investigate the predictive factors for the efficacy of denosumab in postmenopausal patients with breast cancer treated with AI by analyzing the results of two prospective trials. The patients received 60 mg denosumab subcutaneously every 6 months. The primary endpoint was percentage change in lumbar spine bone mineral density (BMD) from baseline to month 12 in lumbar spine. Post hoc analysis and T tests were performed. A total of 205 patients were enrolled. At 12 and 24 months, the lumbar spine BMD increased by 5.6% [95% confidence interval (CI) 4.9-6.3] and 8.3% (95% CI 7.5-9.1), respectively. Subgroup analysis was conducted according to the time of AI therapy initiation, type of AI therapy, age, time since menopause, baseline body mass index, and BMD. The results showed that baseline lumbar and left femoral BMD was significantly associated with a percentage change in these sites, respectively. In addition, baseline left femoral BMD was also associated with a change in lumbar BMD. In conclusion, the baseline BMD in the lumbar spine was a predictive indicator for the efficacy of denosumab in this site and the baseline BMD in left femoral neck was a predictive indicator in lumbar spine and left femur.

Changes in Bone Mineral Density After Prophylactic Bilateral Salpingo-Oophorectomy in Carriers of a BRCA Mutation

IMPORTANCE

Preventive surgery is strongly recommended for individuals with a BRCA mutation at a young age to prevent ovarian cancer and improve overall survival. The overall effect of early surgical menopause on various health outcomes, including bone health, has not been clearly elucidated.

OBJECTIVE

To evaluate the association of prophylactic bilateral salpingo-oophorectomy with bone mineral density (BMD) loss among individuals with a BRCA mutation.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study of participants with a BRCA mutation who underwent oophorectomy through the University Health Network, Toronto, Ontario, Canada, recruited participants from January 2000 to May 2013. Eligibility criteria included having a BRCA mutation, at least 1 ovary intact prior to surgery, and no history of any cancer other than breast cancer. Bone mineral density was measured using dual-energy x-ray absorptiometry before and after surgery. Data analysis began in December 2018 and finished in January 2019.

MAIN OUTCOMES AND MEASURES

The annual change in BMD from baseline to follow-up was calculated for the following 3 anatomical locations: (1) lumbar spine, (2) femoral neck, and (3) total hip.

RESULTS

A total of 95 women had both a baseline and postsurgery BMD measurement with a mean (SD) follow-up period of 22.0 (12.7) months. The mean (SD) age at oophorectomy was 48.0 (7.4) years. Among women who were premenopausal at time of surgery (50 [53%]), there was a decrease in BMD from baseline to follow-up across the lumbar spine (annual change, -3.45%; 95% CI, -4.61% to -2.29%), femoral neck (annual change, -2.85%; 95% CI, -3.79% to -1.91%), and total hip (annual change, -2.24%; 95% CI, -3.11% to -1.38%). Self-reported hormone therapy use was associated with significantly less bone loss at the lumbar spine (-2.00% vs -4.69%; P = .02) and total hip (-1.38% vs -3.21; P = .04) compared with no hormone therapy use. Among postmenopausal women at time of surgery (45 [47%]), there was also a significant decrease in BMD across the lumbar spine (annual change, -0.82%; 95% CI, -1.42% to -0.23%) and femoral neck (annual change, -0.68%; 95% CI, -1.33% to -0.04%) but not total hip (annual change, -0.18%; 95% CI, -0.82% to 0.46%).

CONCLUSIONS AND RELEVANCE

This study found that oophorectomy was associated with postoperative bone loss, especially among women who were premenopausal at the time of surgery. Targeted management strategies should include routine BMD assessment and hormone therapy use to improve management of bone health in this population.

The effects of adjuvant endocrine therapy on bone health in women with breast cancer

In women with oestrogen receptor (ER)-positive early breast cancer, oestradiol is important for breast cancer development and progression. Endocrine therapy prevents the deleterious effects of oestradiol in breast tissue by systemically depleting oestradiol concentration (aromatase inhibitors) or preventing its local action in breast tissue (selective oestrogen receptor modulators i.e. tamoxifen), thereby improving oncological outcomes. Use of aromatase inhibitors in postmenopausal women and ovarian function suppression with either tamoxifen or aromatase inhibition in premenopausal women, consequent to systemic oestradiol depletion, exerts detrimental effects on skeletal health. The oestradiol-deficient state causes increased bone remodelling and a negative bone balance. This results in bone loss, microstructural deterioration and bone fragility predisposing to fractures. Similar effects are also seen with tamoxifen in premenopausal women. In contrast, use of tamoxifen in postmenopausal women appears to exert protective effects on bone but studies on fracture risk are inconclusive. The longevity of women with ER-positive breast cancer treated with adjuvant endocrine therapy emphasises the need to mitigate the adverse skeletal effects of these therapies in order to maximise benefit. In general, fractures are associated with increased morbidity, mortality and are a high socioeconomic burden. Whilst the efficacy of antiresorptive therapy in preventing bone mineral density loss in postmenopausal women has been established, further clinical trial evidence is required to provide guidance regarding fracture risk reduction, when to initiate and stop treatment, choice of agent and optimal management of bone health in premenopausal women receiving endocrine therapy. In addition, potential oncological benefits of antiresorptive therapies will also need to be considered.

Long-Term Endocrine and Metabolic Consequences of Cancer Treatment: A Systematic Review

The number of patients surviving ≥5 years after initial cancer diagnosis has significantly increased during the last decades due to considerable improvements in the treatment of many cancer entities. A negative consequence of this is that the emergence of long-term sequelae and endocrine disorders account for a high proportion of these. These late effects can occur decades after cancer treatment and affect up to 50% of childhood cancer survivors. Multiple predisposing factors for endocrine late effects have been identified, including radiation, sex, and age at the time of diagnosis. A systematic literature search has been conducted using the PubMed database to offer a detailed overview of the spectrum of late endocrine disorders following oncological treatment. Most data are based on late effects of treatment in former childhood cancer patients for whom specific guidelines and recommendations already exist, whereas current knowledge concerning late effects in adult-onset cancer survivors is much less clear. Endocrine sequelae of cancer therapy include functional alterations in hypothalamic-pituitary, thyroid, parathyroid, adrenal, and gonadal regulation as well as bone and metabolic complications. Surgery, radiotherapy, chemotherapy, and immunotherapy all contribute to these sequelae. Following irradiation, endocrine organs such as the thyroid are also at risk for subsequent malignancies. Although diagnosis and management of functional and neoplastic long-term consequences of cancer therapy are comparable to other causes of endocrine disorders, cancer survivors need individually structured follow-up care in specialized surveillance centers to improve care for this rapidly growing group of patients.

Methodological quality of clinical practice guidelines with physical activity recommendations for people diagnosed with cancer: A systematic critical appraisal using the AGREE II tool

Evidence suggests physical activity (PA) is beneficial for people diagnosed with cancer. Clinical practice guidelines provide specific recommendations based on available research and are useful in informing evidence-based practice and guiding future research. Little is known on the extent and quality of guidelines on PA targeted to the cancer population. The objectives of this systematic review were to: 1) identify recent clinical practice guidelines including PA or exercise recommendations for people with cancer and 2) critically appraise the methodological quality of the included guidelines. A systematic search of four electronic databases (MEDLINE, EMBASE, CINAHL and PEDro) and supplementary sources was conducted. Two reviewers independently scanned articles and selected guidelines for inclusion according to the following criteria: published in English, developed or updated in previous five years (January 2012-June 2017), published in peer-reviewed scientific journals, including ≥1 specific recommendation on PA or exercise, and relevant to adults diagnosed with cancer. Subsequently, two trained assessors independently appraised the included guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool. Average scores for six domains (scope and purpose; stakeholder involvement; rigour of development; clarity of presentation; applicability; and editorial independence) and overall quality were calculated. From the literature search, we identified 29 articles, representing 20 sets of guidelines meeting the selection criteria. The guidelines were applicable to the following cancer populations: general (n = 9), breast (n = 5), lung (n = 2), colorectal (n = 1), head and neck (n = 1), myeloma (n = 1) and prostate (n = 1). The guidelines were generally of moderate methodological quality (mean AGREE II overall quality score: 4.6/7, range 2.5-6). The area of lowest quality was in the domain of applicability (mean AGREE II quality domain score: 40%), whereas the strongest domains were related to scope and purpose (81%) and clarity of presentation (77%). Although there are limitations in the primary research informing the recommendations, guidelines of acceptable quality exist to direct stakeholders on targeted PA recommendations for a range of cancer populations. Improvement is needed in the applicability of guidelines to enhance their relevance and clinical use. Health professionals can play an important role in supporting people with cancer throughout the disease trajectory and benefit from access to well-developed and appropriate materials to interpret research knowledge on effective rehabilitation strategies, including PA.

Baseline bone health status in multi-ethnic South African postmenopausal breast cancer patients at initiation of aromatase inhibitor therapy: A descriptive study

Introduction

Osteoporosis (OP) risk factor assessment and bone mineral density (BMD) testing are frequently omitted at baseline in aromatase inhibitor (AI) studies, which may lead to misinterpretation of AI associated bone loss. The present study describes bone health of South African postmenopausal women of predominantly Mixed Ancestry, prior to AI treatment.

Methods

This descriptive baseline study, nested in a prospective AI cohort study, included postmenopausal women with endocrine sensitive breast cancer, aged 50 to 80 years. A baseline questionnaire documented demographic-, medical-, lifestyle- and fracture history. Body weight was assessed clinically, and body composition and BMD measured via dual energy absorptiometry (DXA). Data was analysed in STATA 14 using descriptive and inferential statistics.

Results

101 participants were recruited, with a mean age of 61±7 years. Nearly a third (n = 32) of women at baseline fulfilled global criteria for bone protection (BMD T-score ≥-2SD (n = 18); BMD T-score -1.5SD to < -2SD with risk factors (n = 14). Lower body weight, body mass index (BMI), fat mass index and lean mass index were significantly associated with the participants with a BMD measurement in keeping with a diagnosis of OP (p <0.001). Low vitamin D was present in 93% of the cohort tested (n = 95), whilst deficient vitamin D status (<20ng/ml) was documented in 52 women (55%).

Conclusions

In this study, a third of postmenopausal women considered for AI therapy fulfilled international criteria for bone protective pharmacological intervention. This emphasizes the need for clinical risk and BMD assessment in postmenopausal breast cancer patients at baseline. Body composition and bone health associations highlight bone fragility associated with lower body weight.

DIAGNOSIS OF ENDOCRINE DISEASE: Evaluation of bone fragility in endocrine disorders

An underlying disease affecting bone health is present in up to 40% and 60% of osteoporotic post-menopausal women and men respectively. Among the disorders leading to a secondary form of osteoporosis, the endocrine diseases are highly represented. A frequent finding in patients affected with an endocrine-related forms of bone disease is that the skeletal fragility is partially independent of the bone density, since the fracture risk in these patients is related more to a reduction of bone quality than to a decrease of bone mass. As a consequence, bone mineral density evaluation by dual-X-ray Absorptiometry may be inadequate for establishing the risk of fracture in the setting of the endocrine-related forms of osteoporosis. In the recent years several attempts to non-invasively estimating bone quality have been done. Nowadys, some new tools are available in the clinical practice for optimizing the fracture risk estimation in patients with endocrine disorders. The aim of this review is to summarise the evidences regarding the role of the different imaging tools for evaluating bone density and bone quality in the most frequent forms of endocrine-related osteoporosis, such as obesity, diabetes, acromegaly, thyrotoxicosis, primary hyperparathyroidism, hypercortisolism and hypogonadism. For each of these disorders, data regarding both the current available tools and the future possible new techniques for assessing bone fragility in patients with endocrine diseases are reported.

Bone health in women with breast cancer

Women with early, estrogen receptor-positive breast cancer are treated with adjuvant endocrine therapy, using aromatase inhibitors or selective estradiol receptor modulators such as tamoxifen, to deprive breast tissue from the deleterious effects of estradiol action, hence improving long-term prognosis. Aromatase inhibitors and, in premenopausal women, tamoxifen accelerate bone loss and increase fracture risk. Therefore, all women commencing endocrine therapy need a targeted work-up to assess the baseline fracture risk, and monitoring of bone health during endocrine therapy should be individualized based on this baseline risk. While high-level evidence specific to early breast cancer is lacking, non-pharmacologic measures to maintain optimal bone health such as weight-bearing exercise and calcium and vitamin D sufficiency should be implemented in all women. Antiresorptive treatment should be initiated in all women with preexisting fragility fractures (including vertebral morphometric fractures) and should be considered in women with areal bone mineral density (BMD) T-scores < -2.0 (or Z-scores in women aged <50 years) or those experiencing rapid bone loss (≥5% per year), taking into consideration the baseline BMD and other risk factors for fracture. Further clinical trial evidence is required to provide definitive guidance regarding criteria to initiate antiresorptive treatment, choice of agents, and duration of treatment, taking into account potential oncologic benefits of antiresorptive therapy on breast cancer-related outcomes.

The skeletal impact of cancer therapies

Both cancer and therapies used in the treatment of cancer can have significant deleterious effects on the skeleton, increasing the risks for both bone loss and fracture development. While advancements in cancer therapies have resulted in enhanced cancer survivorship for patients with many types of malignancies, it is increasingly recognized that efforts to reduce bone loss and limit fractures must be considered for nearly all patients undergoing cancer therapy in order to diminish the anticipated future skeletal consequences. To date, most studies examining the impact of cancer therapies on skeletal outcomes have focused on endocrine-associated cancers of the breast and prostate, with more recent advances in our understanding of bone loss and fracture risk in other malignancies. Pharmacologic efforts to limit the adverse effects of cancer therapies on bone have nearly universally employed anti-resorptive approaches, although studies have frequently relied on surrogate outcomes such as changes in bone mineral density or bone turnover markers, rather than on fractures or other skeletal-related events, as primary study endpoints. Compounding current deficiencies for the provision of optimal care is the recognition that despite clearly written and straightforward society-based guidelines, vulnerable eligible patients are very often neither identified nor provided with appropriate treatments to limit the skeletal impact of their cancer therapies.

Compliance and patient reported toxicity from oral adjuvant bisphosphonates in patients with early breast cancer. A cross sectional study

Background

Adjuvant bisphosphonates (BPs) are recommended as part of routine early breast cancer treatment for many postmenopausal (PM) women within the past year. There is a paucity of ‘real world’ data on compliance and patient satisfaction with oral BPs in this population. The aim of our study was to investigate patient reported compliance and toxicity of these drugs in a retrospective cohort study.

Patients and methods

413 patient were identified as receiving adjuvant oral BPs as part of their breast cancer treatment in the past 12 months from five NHS hospitals. The validated Osteoporosis Patient Treatment Satisfaction Questionnaire (OPSAT-Q) was sent to all suitable patients (n = 389).

Results

295 (76%) of patients responded. Average age was median (range) 67 (35–89). The majority of patients had T1 (52%), N0 (61%) grade 2 (58%) ER positive (87%), HER2 negative (84%) breast cancer and were PM at diagnosis of breast cancer (93%). All patients had been prescribed at least 1 month of oral ibandronate 50 mg daily. Review of items rated on the 7-point scale (1 = very dissatisfied to 7 = very satisfied), the mean item scores ranged from 5.0 (lowest) for time required to take oral BPs, to 6.1 (highest) for how easy it is to remember to take the medication. <10% of patients were extremely bothered by heartburn or stomach upset. 16% of responders stopped oral BPs with 10% of those converting onto IV BPs.

Conclusions

Prevalence of severe side effects in a ‘real world’ population of PM women receiving adjuvant BPs is low and these drugs are generally well accepted and tolerated by patients.

RANKL/RANK/OPG system beyond bone remodeling: involvement in breast cancer and clinical perspectives

RANKL/RANK/OPG system consists of three essential signaling molecules: i) the receptor activator of nuclear factor (NF)-kB-ligand (RANKL), ii) the receptor activator of NF-kB (RANK), and iii) the soluble decoy receptor osteoprotegerin (OPG). Although this system is critical for the regulation of osteoclast differentiation/activation and calcium release from the skeleton, different studies have elucidated its specific role in mammary gland physiology and hormone-driven epithelial proliferation during pregnancy. Of note, several data suggest that progesterone induces mammary RANKL expression in mice and humans. In turn, RANKL controls cell proliferation in breast epithelium under physiological conditions typically associated with higher serum progesterone levels, such as luteal phase of the menstrual cycle and pregnancy. Hence, RANKL/RANK system can be regarded as a major downstream mediator of progesterone-driven mammary epithelial cells proliferation, potentially contributing to breast cancer initiation and progression. Expression of RANKL, RANK, and OPG has been detected in breast cancer cell lines and in human primary breast cancers. To date, dysregulation of RANKL/RANK/OPG system at the skeletal level has been widely documented in the context of metastatic bone disease. In fact, RANKL inhibition through the RANKL-blocking human monoclonal antibody denosumab represents a well-established therapeutic option to prevent skeletal-related events in metastatic bone disease and adjuvant therapy-induced bone loss in breast cancer. On the other hand, the exact role of OPG in breast tumorigenesis is still unclear. This review focuses on molecular mechanisms linking RANKL/RANK/OPG system to mammary tumorigenesis, highlighting pre-clinical and clinical evidence for the potential efficacy of RANKL inhibition as a prevention strategy and adjuvant therapy in breast cancer settings.

The Roles of Common Variation and Somatic Mutation in Cancer Pharmacogenomics

Cancer pharmacogenomics is the science concerned with understanding genetic alterations and its effects on the pharmacokinetics and pharmacodynamics of anti-cancer drugs, with the aim to provide cancer patients with the precise medication that will achieve a good response and cause low/no incidence of adverse events. Advances in biotechnology and bioinformatics have enabled genomic research to evolve from the evaluation of alterations at the single-gene level to studies on the whole-genome scale using large-scale genotyping and next generation sequencing techniques. International collaborative efforts have resulted in the construction of databases to curate the identified genetic alterations that are clinically significant, and these are currently utilized in clinical sequencing and liquid biopsy screening/monitoring. Furthermore, countless clinical studies have accumulated sufficient evidence to match cancer patients to therapies by utilizing the information of clinical-relevant alterations. In this review we summarize the importance of germline alterations that act as predictive biomarkers for drug-induced toxicity and drug response as well as somatic mutations in cancer cells that function as drug targets. The integration of genomics into the medical field has transformed the era of cancer therapy from one-size-fits-all to cancer precision medicine.

Hormone therapy and osteoporosis in breast cancer survivors: assessment of risk and adherence to screening recommendations

The long-term impact of hormone therapy for breast cancer on risk of osteoporosis and the extent to which bone screening recommendations are implemented in daily practice remain unknown. We found that the aromatase inhibitor-induced risk of osteoporosis did not continue in the off-treatment follow-up. Adherence to screening recommendations was suboptimal.

INTRODUCTION

A case-cohort study was undertaken to better understand the impact of hormone therapy on breast cancer patients' risk of osteoporosis, and to estimate the extent to which current bone mineral density screening recommendations are implemented in real-life daily practice.

METHODS

This study is based on 1692 female breast cancer survivors recruited from "Leumit" healthcare fund, who were diagnosed with primary nonmetastatic invasive breast cancer between 2002 and 2012. A 20% random subcohort was sampled at baseline, and all osteoporosis cases were identified. Adjusted hazard ratios (HR) with 95% confidence intervals (CI) were estimated by weighted Cox proportional hazards models.

RESULTS

Of 1692 breast cancer survivors, 312 developed osteoporosis during a median follow-up of 5 years. The crude cumulative incidence of osteoporosis accounting for death as a competing risk was 25.7% (95% CI, 21.9-29.5%). In multivariable analyses, osteoporosis was positively associated with the aromatase inhibitor (AI) sequential treatment after tamoxifen (HR, 3.14; 95% CI, 1.44-6.88; P = .004) but was more pronounced with AI use as upfront monotherapy (HR, 5.53; 95% CI, 1.46-20.88; P = .012). This effect did not continue in the off-treatment follow-up. In subgroup analysis by menopausal status, tamoxifen did not seem to confer a protective effect on bone health in postmenopausal patients. Adherence to screening recommendations in AI-treated postmenopausal women was suboptimal, particularly at baseline and after 48 months of continuous AI use.

CONCLUSIONS

The natural, age-related reduction in bone density is exacerbated by breast cancer active AI treatment. Future research should focus on investigating screening adherence-related barriers/facilitators and effective strategies to bring practice in line with agreed standards.

Trends in vitamin D supplement use in a general female and breast cancer population in Ireland: A repeated cross-sectional study

Background

Vitamin D has been linked with improved survival after breast cancer diagnosis but little is known about prescribing rates. This study investigates trends in vitamin D supplement use in both a general female and breast cancer population.

Methods

Women with a breast cancer diagnosis were identified from the National Cancer Registry of Ireland (n = 19870). Women who had any vitamin D claim between 2005 and 2011 were identified from pharmacy claims data (n = 8556). Prevalence rates were calculated as a proportion of all eligible women and by age (< 55 years, ≥ 55 years). Poisson regression was used to compare rates of vitamin D prescribing across years (risk ratio (RR), 95% CI).

Results

There was a statistically significant increase in women with a claim for vitamin D between 2005–2011, with the largest increase among breast cancer patients aged ≥ 55 years (RR = 2.26; 95% CI, 2.11–2.42).

Conclusion

This may have significant public health implications if associations between vitamin D and improved breast cancer survival prove to be causal.

Bone health evaluation one year after aromatase inhibitors completion

INTRODUCTION

Breast cancer patients treated with aromatase inhibitors (AIs) experience increased bone loss during their treatment. However, there is little information about bone mineral density (BMD) after completing AI-treatment. The present study aimed to assess BMD changes one year after AI-therapy completion.

METHODS

Data were collected from 864 postmenopausal women treated with AI during 5 years (5y-AI group), or during 2-3 years after taking tamoxifen therapy (pTAM-AI group). Participants with osteoporosis were treated with oral bisphosphonates (BP). BMD changes in lumbar spine (LS), femoral neck (FN) and total hip (TH) between baseline, end of treatment, and at one year post-treatment were assessed using repeated-measures ANOVA.

RESULTS

At the end of AI-treatment, 382 patients had available BMD values and 316 also had post-treatment BMD values. As expected, BMD levels were decreased at AI-completion in non-BP treated patients. After one year, LS BMD increased in both groups (5y-AI: +2.11% [95%CI: 1.55 to 2.68], p < 0.001; pTAM-AI: +1.00% [95%CI: 0.49 to 1.51], p < 0.001) compared with the end of AI-therapy, while values at FN and TH remained stable. On the other hand, BMD values of BP-treated patients were increased or maintained at the end of AI-treatment and also at post-treatment.

CONCLUSIONS

At one year after AI-completion, FN and TH BMD remained reduced in non-BP treated women, while LS BMD was recovered in the 5y-AI group and partially recovered in the pTAM-AI group. BP treatment increased or maintained BMD values at the end of therapy and at one year post-treatment.