Long-term effects of aromatase inhibitor withdrawal on bone mineral density in early breast cancer patients: 10-year follow-up results of the BREX study

PURPOSE

We aimed to provide long-term bone mineral density (BMD) data on early breast cancer patients of the BREX (Breast Cancer and Exercise) study. The effects of exercise and adjuvant endocrine treatment 10 years after randomization were analyzed, with special emphasis on aromatase inhibitor (AI) therapy discontinuation at 5 years.

METHODS

The BREX study randomized 573 pre- and postmenopausal breast cancer patients into a 1-year supervised exercise program or a control group. 372 patients were included into the current follow-up analysis. BMD (g/cm2) was measured by dual-energy X-ray absorptiometry at lumbar spine (LS), left femoral neck (FN), and the total hip. Separate groups were displayed according to baseline menopausal status, and whether the patient had discontinued AI therapy at 5 years or not.

RESULTS

The BMD change from 5 to 10 years did not significantly differ between the two randomized arms. AI discontinuation at 5 years had statistically significant BMD effects. The FN BMD continued to decrease in patients who discontinued AI therapy during the first 5-year off-treatment, but the decrease was three-fold less than in patients without AI withdrawal (- 1.4% v. - 3.8%). The LS BMD increased (+ 2.6%) in patients with AI withdrawal during the first 5 years following treatment discontinuation, while a BMD decrease (-1.3%) was seen in patients without AI withdrawal.

CONCLUSION

This study is to our knowledge the first to quantify the long-term impact of AI withdrawal on BMD. Bone loss associated with AI therapy seems partially reversible after stopping treatment.

TRIAL REGISTRATION

http://www.

CLINICALTRIALS

gov/ (Identifier Number NCT00639210).

Osteoporotic fracture risk in women with breast cancer treated with aromatase inhibitors: a health insurance claims database study in Japan

BACKGROUND

Hormone therapy with aromatase inhibitors (AIs) for estrogen receptor-dependent breast cancer may expose patients to an increased osteoporosis risk. This study was performed to estimate fracture risk in women with breast cancer to whom AIs were prescribed in Japan.

METHODS

This retrospective study used data from the Japanese Medical Data Vision database. Women with breast cancer prescribed AIs over a 12-month period were identified and matched to women not prescribed AIs using a propensity score. Fracture rates were estimated by a cumulative incidence function and compared using a cause-specific Cox hazard model. The proportion of women undergoing bone density tests was retrieved.

RESULTS

For all fractures sites combined, cumulative fracture incidence at 10 years was 0.19 [95%CI: 0.16-0.22] in women prescribed AIs and 0.18 [95%CI: 0.15-0.21] without AIs. AI prescription was not associated with any changes in risk (adjusted hazard ratio: 1.08 [95%CI: 0.99-1.17] p = 0.08). Women prescribed AI more frequently underwent bone density testing (31.9% [95% CI: 31.2%; 32.6%] versus 2.2% [95% CI: 2.0%; 2.4%]).

CONCLUSIONS

The anticipated association between AI exposure and osteoporotic fracture risk in Japanese women with breast cancer was not seen clearly.

Adapting and implementing breast cancer follow-up in primary care: protocol for a mixed methods hybrid type 1 effectiveness-implementation cluster randomized study

BACKGROUND

Advances in detection and treatment for breast cancer have led to an increase in the number of individuals managing significant late and long-term treatment effects. Primary care has a role in caring for patients with a history of cancer, yet there is little guidance on how to effectively implement survivorship care evidence into primary care delivery.

METHODS

This protocol describes a multi-phase, mixed methods, stakeholder-driven research process that prioritizes actionable, evidence-based primary care improvements to enhance breast cancer survivorship care by integrating implementation and primary care transformation frameworks: the Exploration, Preparation, Implementation, and Sustainment (EPIS) framework and the Practice Change Model (PCM). Informed by depth interviews and a four round Delphi panel with diverse stakeholders from primary care and oncology, we will implement and evaluate an iterative clinical intervention in a hybrid type 1 effectiveness-implementation cluster randomized design in twenty-six primary care practices. Multi-component implementation strategies will include facilitation, audit and feedback, and learning collaboratives. Ongoing data collection and analysis will be performed to optimize adoption of the intervention. The primary clinical outcome to test effectiveness is comprehensive breast cancer follow-up care. Implementation will be assessed using mixed methods to explore how organizational and contextual variables affect adoption, implementation, and early sustainability for provision of follow-up care, symptom, and risk management activities at six- and 12-months post implementation.

DISCUSSION

Study findings are poised to inform development of scalable, high impact intervention processes to enhance long-term follow-up care for patients with a history of breast cancer in primary care. If successful, next steps would include working with a national primary care practice-based research network to implement a national dissemination study. Actionable activities and processes identified could also be applied to development of organizational and care delivery interventions for follow-up care for other cancer sites.

TRIAL REGISTRATION

Registered with ClinicalTrials.gov on June 2, 2022: NCT05400941.

Proceedings of the 2023 Santa Fe Bone Symposium: Progress and Controversies in the Management of Patients with Skeletal Diseases

The Santa Fe Bone Symposium (SFBS) held its 23rd annual event on August 5-6, 2023, in Santa Fe, New Mexico, USA. Attendees participated in-person and remotely, representing many states and countries. The program included plenary presentations, panel discussions, satellite symposia, a Project ECHO workshop, and a session on healthcare policy and reimbursement for fracture liaison programs. A broad range of topics were addressed, including transitions of osteoporosis treatments over a lifetime; controversies in vitamin D; update on Official Positions of the International Society for Clinical Densitometry; spine surgery and bone health; clinical applications of bone turnover markers; basic bone biology for clinicians; premenopausal-, pregnancy-, and lactation-associated osteoporosis; cancer treatment induced bone loss in patients with breast cancer and prostate cancer; genetic testing for skeletal diseases; and an update on nutrition and bone health. There were also sessions on rare bone diseases, including managing patients with hypophosphatasia; treatment of X-linked hypophosphatemia; and assessment and treatment of patients with hypoparathyroidism. There were oral presentations of abstracts by endocrinology fellows selected from those who participated in the Santa Fe Fellows Workshop on Metabolic Bone Diseases, held the 2 days prior to the SFBS. These proceedings of the 2023 SFBS present the clinical highlights and insights generated from many formal and informal discussions in Santa Fe.

Oral Health in Breast Cancer Women with Vitamin D Deficiency: A Machine Learning Study

Breast cancer (BC) survivors treated with aromatase inhibitors (AIs) commonly show several pathological issues, including poor oral health, bone health impairment, and vitamin D deficiency. However, to date, oral health issues in BC survivors treated with AIs have been poorly investigated and their relationship with vitamin D deficiency are far from being understood. This study aimed to evaluate the correlation between oral health and vitamin D status in BC survivors undergoing treatment with AIs through a machine learning approach. In this cross-sectional study, we included post-menopausal BC women with vitamin D deficiency undergoing AIs therapy. The outcome measures were the following: oral health indexes as the Decayed, Missing, and Filled Permanent Teeth Index (DMFT); serum levels of 25(OH)D₃; Bone Mineral Density (BMD); and the diagnosis of osteoporosis. We included 41 post-menopausal BC women, mean aged 66.10 ± 8.47 years, with mean serum levels of vitamin D of 14.63 ± 6.62 ng/mL. Furthermore, 56.10% of patients had a diagnosis of osteoporosis and 36.59% were osteopenic. DMFT was significantly related to smoking (p-value = 0.005) and dental floss use (p-value = 0.001). There was a significant correlation between DMFT and vitamin D levels (Pearson’s r: −0.73; p-value = 0.001). The regression machine learning model showed that vitamin D status and the use of dental floss were the most relevant variables in terms of correlation with DMFT. In conclusion, vitamin D deficiency, inadequate use of dental floss, and smoking had a negative impact on oral health in BC women. Thus, vitamin D deficiency screening and supplementation and a prompt oral rehabilitation plan should be suggested and implemented in the complex treatment framework of BC survivors undergoing treatment with AIs.

Metastatic Breast Cancer Recurrence after Bone Fractures

Simple Summary

Bone fractures bear potential risk to promote metastatic relapse in breast cancer. We conducted a population-based cohort study of 84,300 breast cancer patients diagnosed between January 2015 and November 2019. Bone fracture after breast cancer diagnosis was associated with an increased metastasis risk. Fractures may pose an increased risk to developing metastasis. Potential clinical implications for cancer patients are in support of fall prevention programs.

Abstract

Experimental studies suggest that bone fractures result in the release of cytokines and cells that might promote metastasis. Obtaining observational data on bone fractures after breast cancer diagnoses related to distant breast cancer recurrence could help to provide first epidemiological evidence for a metastasis-promoting effect of bone fractures. We used data from the largest German statutory health insurance fund (Techniker Krankenkasse, Hamburg, Germany) in a population-based cohort study of breast cancer patients with ICD-10 C50 codes documented between January 2015 and November 2019. The risk of metastasis overall, regional, distant non-bone or bone metastasis related to a fracture was modeled by an adjusted discrete time-to-event analysis with time-dependent exposure. Of 154,000 breast cancer patients, 84,300 fulfilled the inclusion criteria and had a follow-up time of more than half a year. During follow-up, fractures were diagnosed in 13,579 (16.1%) patients. Metastases occurred in 7047 (8.4%) patients; thereof 1544 had affected regional lymph nodes only and 5503 distant metastases. Fractures demonstrated a statistically significant association with subsequent metastasis overall (adjusted HR 1.12, 95% CI 1.04, 1.20). The highest risk for metastasis was observed in patients with subsequent bone metastasis (adjusted HR 1.18, 95% CI 1.05, 1.34), followed by distant non-bone metastasis (adjusted HR 1.16, 95% CI 1.07, 1.26) and lymph node metastasis (adjusted HR 1.08, 95% CI 0.97, 1.21).

Adjuvant endocrine therapy effects on bone mineral density and microstructure in women with breast cancer

INTRODUCTION

Although aromatase inhibitors (AIs) are typical drugs for cancer treatment-induced bone loss, their effects on the bone microstructure remain unclear. In this study, we evaluated changes in the bone mineral density (BMD) and bone microstructure associated with AI treatment using high-resolution peripheral quantitative computed tomography (HR-pQCT) in patients with early breast cancer.

MATERIALS AND METHODS

This prospective, single-arm, observational study included non-osteoporotic, postmenopausal women with hormone receptor-positive breast cancer. Patients underwent dual-energy X-ray absorptiometry (DXA), HR-pQCT, and tartrate-resistant acid phosphatase-5b (TRACP-5b) or procollagen type-I N-terminal propeptide measurements at baseline and 6 and 12 months after AI therapy. The primary endpoint was changes in the total volumetric BMD (Tt.vBMD), trabecular vBMD (Tb.vBMD), and cortical vBMD (Ct.vBMD) longitudinally at the distal radius and tibia.

RESULTS

Twenty women were included (median age 57.5 years; range 55-72 years). At 12 months, HR-pQCT indicated a significant decrease in the Tt.vBMD (median distal radius - 5.3%, p < 0.01; distal tibia - 3.2%, p < 0.01), Tb.vBMD (- 3.2%, p < 0.01; - 1.0%, p < 0.05, respectively), and Ct.vBMD (- 3.2%, p < 0.01; - 2.7%, p < 0.01, respectively). Estimated bone strength was also significantly decreased. The DXA BMD value in the total hip (p < 0.01) and femoral neck (p = 0.03), but not in the lumbar spine, was significantly decreased. The TRACP-5b levels was significantly negatively associated with changes in the Tt.vBMD in both the distal radius and tibia (r =  - 0.53, r =  - 0.47, respectively) CONCLUSION: Postmenopausal women who received AIs for early breast cancer experienced significant trabecular and cortical bone deterioration and a decrease in estimated bone strength within only 1 year.

Quality of Life Interventions in Breast Cancer Survivors: State of the Art in Targeted Rehabilitation Strategies

Breast cancer is the most common malignant tumor and the most prevalent cause of mortality in women. Advances in early diagnosis and more effective adjuvant therapies have improved the long-term survival of these patients. Pharmacotherapies and intrinsic tumor-related factors may lead to a wide spectrum of treatment-related disabling complications, such as breast cancer-related lymphedema, axillary web syndrome, persistent pain, bone loss, arthralgia, and fatigue. These conditions have a detrimental impact on the health-related quality of life of survivors. Here, we sought to provide a portrait of the role that rehabilitation plays in breast cancer survivors. Particular emphasis has been placed on recovering function, improving independence in activities of daily living, and reducing disability. This complex scenario requires a precision medicine approach to provide more effective decision-making and adequate treatment compliance.

Updated guidance on the management of cancer treatment-induced bone loss (CTIBL) in pre- and postmenopausal women with early-stage breast cancer

INTRODUCTION

Adjuvant endocrine therapy induces bone loss and increases fracture risk in women with hormone-receptor positive, early-stage breast cancer (EBC). We aimed to update a previous position statement on the management of aromatase inhibitors (AIs) induced bone loss and now included premenopausal women.

METHODS

We conducted a systematic literature search of the medical databases from January 2017 to May 2020 and assessed 144 new studies.

RESULTS

Extended use of AIs beyond 5 years leads to persistent bone loss in breast cancer extended adjuvant trials and meta-analyses. In addition to bone mineral density (BMD), vertebral fracture assessment (VFA) and trabecular bone score (TBS) were shown to independently predict fracture risk in real life prospective studies. FRAX® tool does not seem to be reliable for assessing fracture risk in CTIBL. In premenopausal women, there is strong evidence that intravenous zoledronate prevents bone loss but weak conflicting evidence on reducing disease recurrence from independent randomised controlled trials (RCTs). In postmenopausal women, the strongest evidence for fracture prevention is for denosumab based on a well-powered RCT while there is strong evidence for bisphosphonates (BPs) to prevent and reduce CTIBL but no convincing data on fractures. Adjuvant denosumab has failed to show anticancer benefits in a large, well-designed RCT.

DISCUSSION AND CONCLUSIONS

Extended use of AIs and persistent bone loss from recent data reinforce the need to evaluate fracture risk in EBC women initiated on AIs. Fracture risk should be assessed with clinical risk factors and BMD along with VFA, but FRAX is not adapted to CTIBL. Anti-resorptive therapy should be considered in those with a BMD T-score < -2.0 SD or with ≥ 2 clinical risk factors including a BMD T-score < -1.0 SD. In premenopausal women, intravenous zoledronate is the only drug reported to prevent bone loss and may have additional anticancer benefits. In postmenopausal women, either denosumab or BPs can be prescribed for fracture prevention with pertinent attention to the rebound phenomenon after stopping denosumab. Adjuvant BPs, in contrast to denosumab, have shown high level evidence for reducing breast cancer recurrence in high-risk post-MP women which should be taken into account when choosing between these two.

Cancer Treatment-Induced Bone Loss (CTIBL): State of the Art and Proper Management in Breast Cancer Patients on Endocrine Therapy

OPINION STATEMENT

About 70-80% of early breast cancer (BC) patients receive adjuvant endocrine therapy (ET) for at least 5 years. ET includes in the majority of cases the use of aromatase inhibitors, as upfront or switch strategy, that lead to impaired bone health. Given the high incidence and also the high prevalence of BC, cancer treatment-induced bone loss (CTIBL) represents the most common long-term adverse event experimented by patients with hormone receptor positive tumours. CTIBL is responsible for osteoporosis occurrence and, as a consequence, fragility fractures that may negatively affect quality of life and survival expectancy. As recommended by main international guidelines, BC women on aromatase inhibitors should be carefully assessed for their fracture risk at baseline and periodically reassessed during adjuvant ET in order to early detect significant worsening in terms of bone health. Antiresorptive agents, together with adequate intake of calcium and vitamin D, should be administered in BC patients during all course of ET, especially in those at high risk of osteoporotic fractures, as calculated by tools available for clinicians. Bisphosphonates, such as zoledronate or pamidronate, and anti-RANKL antibody, denosumab, are the two classes of antiresorptive drugs used in clinical practice with similar efficacy in preventing bone loss induced by aromatase inhibitor therapy. The choice between them, in the absence of direct comparison, should be based on patients' preference and compliance; the different safety profile is mainly related to the route of administration, although both types of drugs are manageable with due care, since most of the adverse events are predictable and preventable. Despite advances in management of CTIBL, several issues such as the optimal time of starting antiresorptive agents and the duration of treatment remain unanswered. Future clinical trials as well as increased awareness of bone health are needed to improve prevention, assessment and treatment of CTIBL in these long-term survivor patients.

Off-treatment bone mineral density changes in postmenopausal women receiving anastrozole for 5 years: 7-year results from the IBIS-II prevention trial

BACKGROUND

Anastrozole has been associated with substantial accelerated bone mineral density (BMD) loss during active treatment.

METHODS

One thousand four hundred and ten women were included in a BMD substudy and stratified into three strata according to their baseline T-score at spine or femoral neck. The primary objective of this analysis was to investigate whether DXA BMD at the spine and hip changed two years after treatment cessation (between years 5 and 7) in those who did not receive risedronate.

RESULTS

Five- and seven-year BMD data were available for a total of 528 women who did not receive risedronate. In women with normal BMD at baseline, an increase in BMD at the lumbar spine after anastrozole withdrawal was observed 1.25% (95% CI 0.73 to 1.77) (P = 0.0004), which was larger than in those on placebo (0.14% (-0.29 to 0.56))). At the hip, BMD remained unchanged between years 5 and 7 for those previously on anastrozole but continued to a decrease in those who had been randomised to placebo (-1.35% (-1.70 to -0.98)).

CONCLUSIONS

These are the first results reporting BMD changes after stopping anastrozole in a breast cancer prevention setting. Our results show that the negative effects of anastrozole on BMD in the preventive setting are partially reversible.

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).

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.

Drugs Causing Bone Loss

Drugs may cause bone loss by lowering sex steroid levels (e.g., aromatase inhibitors in breast cancer, GnRH agonists in prostate cancer, or depot medroxyprogestone acetate - DMPA), interfere with vitamin D levels (liver inducing anti-epileptic drugs), or directly by toxic effects on bone cells (chemotherapy, phenytoin, or thiazolidinedions, which diverts mesenchymal stem cells from forming osteoblasts to forming adipocytes). However, besides effects on the mineralized matrix, interactions with collagen and other parts of the unmineralized matrix may decrease bone biomechanical competence in a manner that may not correlate with bone mineral density (BMD) measured by dual energy absorptiometry (DXA).Some drugs and drug classes may decrease BMD like the thiazolidinediones and consequently increase fracture risk. Other drugs such as glucocorticoids may decrease BMD, and thus increase fracture risk. However, glucocorticoids may also interfere with the unmineralized matrix leading to an increase in fracture risk, not mirrored in BMD changes. Some drugs such as selective serotonin reuptake inhibitors (SSRI), paracetamol, and non-steroidal anti-inflammatory drugs (NSAIDs) may not per se be associated with bone loss, but fracture risk may be increased, possibly stemming from an increased risk of falls stemming from effects on postural balance mediated by effects on the central nervous system or cardiovascular system.This paper performs a systematic review of drugs inducing bone loss or associated with fracture risk. The chapter is organized by the Anatomical Therapeutic Chemical (ATC) classification.

French recommendations on strategies for preventing and treating osteoporosis induced by adjuvant breast cancer therapies

Standard adjuvant therapies for breast cancer such as chemotherapy or aromatase inhibitor and LH-RH agonist hormone therapy are associated with significant survival gains but also induce bone loss by aggravating the estrogen deprivation. The bone loss may be substantial, notably during early treatment, and occurs regardless of the baseline bone mineral density values. The objective of developing these recommendations was to achieve a practical consensus among various scientific societies, based on literature review, about osteoporosis prevention and treatment in these patients. The following scientific societies contributed to the work: Société Française de Rhumatologie (SFR), Groupe de Recherche et d'Information sur les Ostéoporoses (GRIO), Groupe Européen d'Etudes des Métastases Osseuses (GEMO), Association Francophone pour les Soins Oncologiques de Support (AFSOS), Société Française de Sénologie et de Pathologie Mammaire (SFSPM), Société Française de Radiothérapie Oncologique (SFRO). Drug prescription and reimbursement modalities in France were taken into account. These recommendations apply to postmenopausal women taking systemic chemotherapy and/or aromatase inhibitor therapy, non-postmenopausal women taking LH-RH agonist therapy, and non-postmenopausal women with persistent amenorrhea 1 year after chemotherapy completion. All women in these three categories should undergo an evaluation of bone health and receive interventions to combat risk factors for bone loss. Patients with a history of severe osteoporotic fracture and/or a T-score value <-2.5 should receive osteoporosis drug therapy. The FRAX® score should be used to guide treatment decisions in patients whose T-score is between -1 and -2.5. General osteoporosis prevention measures should be applied in patients without criteria for osteoporosis drug therapy, who should undergo bone mineral density measurements 18-24 months later if the baseline T-score is<-1 and 3-5 years later if the baseline T-score is>-1. The anti-tumor effect of bisphosphonates and denosumab was not considered when establishing these recommendations.

Assessment and management of bone health in women with early breast cancer receiving endocrine treatment in the DATA study

The phase III DATA study investigates the efficacy of adjuvant anastrozole (6 vs. 3 year) in postmenopausal women with breast cancer previously treated with 2–3 years of tamoxifen. This planned side‐study assessed patterns of care regarding detection and treatment of osteopenia/osteoporosis, and trends in bone mineral density (BMD) during and after therapy. We registered all BMD measurements and bisphosphonate‐use. Time to osteopenia/osteoporosis was analysed by Kaplan Meier methodology. For the trend in T‐scores we used linear mixed models with random patients effects. Of 1860 eligible DATA patients, 910 (48.9%) had a baseline BMD measurement. Among patients with a normal baseline BMD (n = 417), osteopenia was observed in 53.5% and 55.4% in the 6‐ and 3‐year group respectively (p = 0.18), during follow‐up. Only two patients (3‐year group) developed osteoporosis. Of the patients with osteopenia at baseline (n = 408), 24.4% and 20.4% developed osteoporosis respectively (p = 0.89). Three years after randomisation 18.3% and 18.2% used bisphosphonates in the 6‐ and 3‐year groups respectively and 6 years after randomisation this was 23.7% and 20.9% respectively (p = 0.90) of which the majority used oral bisphosphonates. The yearly mean BMD‐change during anastrozole in the lumbar spine showed a T‐score decline of 0.075. After bisphosphonate addition the decline became less prominent (0.047 (p < 0.001)) and after anastrozole cessation, while continuing bisphosphonates, the mean BMD yearly increased (0.047 (p < 0.001)). In conclusion, extended anastrozole therapy was not associated with a higher incidence of osteoporosis. Anastrozole‐use was associated with a BMD decrease; however, the decline was modest and partially reversible after anastrozole cessation.

What's new?

Loss of bone mineral density (BMD) is a side effect of aromatase inhibitor treatment, a class of drugs that stops estrogen production in postmenopausal women with breast cancer. Here the authors examined BMD loss during and after extended adjuvant endocrine therapy, following a 2‐3 year treatment with tamoxifen, subsequent aromatase inhibitor treatment was associated with BMD decrease, but the decline was modest and partially reversible after treatment cessation. The authors concluded that extended endocrine therapy was not associated with a higher incidence of osteoporosis.

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.

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.

Bone-Modifying Agents in Early-Stage and Advanced Breast Cancer

PURPOSE OF REVIEW

Bone-modifying agents have an important role in the treatment of patients with bone mineral density loss, early-stage breast cancer to reduce risk of recurrence, and metastatic breast cancer with bone involvement. Here we review mechanisms of action of these agents and clinical indications for their use.

RECENT FINDINGS

The meta-analysis undertaken by the Early Breast Cancer Trialists' Collaborative Group showed that the use of bisphosphonates was associated with a decreased risk of breast cancer recurrence.

SUMMARY

The effect of bisphosphonates and receptor activator of nuclear factor kappa-B ligand inhibitors on bone health provides an opportunity to decrease the incidence of skeletal-related events and improve cancer outcomes in certain subsets of patients.

Long-term effect of exemestane therapy on bone mineral density supported by bisphosphonates: Results of 5-year adjuvant treatment in postmenopausal women with early-stage breast cancer

PURPOSE

Unlike anastrozole, the effect of long-term exemestane (EXE) therapy on bone mineral density (BMD) is still unknown. We assessed changes in BMD from baseline to 5 years of EXE treatment.

METHODS

Postmenopausal women with endocrine-responsive breast cancer receiving EXE as adjuvant therapy were enrolled in this study. EXE was administered for 5 years. The BMD of the lumbar spine (LS) and femoral neck (FN) was assessed by dual-energy X-ray absorptiometry at baseline and after 6 months and 1, 2, 3, 4, 5 and 6 years. Oral bisphosphonate (Bis) treatment was initiated when patients were diagnosed with osteoporosis with a T-score of -2.5 or lower.

RESULTS

Eighty-one patients were enrolled in the study between 2005 and 2010. The median follow-up period was 54.9 months. Forty-two patients were administered Bis. Overall, the BMD of the LS increased by 7.3% from baseline and that of the FN increased by 3.4% with 5 years of EXE treatment. At the sixth year (i.e. 1 year after the treatment), BMD of the LS increased by 7.2% and that of the FN increased by 5.7%. Furthermore, the BMD of the FN increased by 12.0% in patients treated upfront with Bis and by 1.2% in those not treated with Bis (P = 0.0262). Fractures developed in nine patients (11.1%) and seven (8.6%) had fragility fractures.

CONCLUSION

Oral Bis improves BMD of the FN in patients with osteoporosis. Five-year EXE treatment with proper addition of Bis helps maintain the BMD of the LS and FN at the sixth year.

Cancer Treatment-Induced Bone Loss in Women With Breast Cancer and Men With Prostate Cancer

Cancer and cancer therapies can have a negative impact on bone health. Because cancer is a common diagnosis, survivorship concerns for osteoporosis and fragility fractures are an important component of care. This review addresses management of bone health in nonmetastatic cancer survivorship with a focus on breast cancer and prostate cancer.

Aromatase inhibitors are associated with a higher fracture risk than tamoxifen: a systematic review and meta-analysis

Background

In this paper, our aim was to systematically evaluate published evidence of bone fracture risk associated with tamoxifen and aromatase inhibitors in women aged 65 and under, and diagnosed with nonmetastatic breast cancer.

Methods

We comprehensively searched MEDLINE, EMBASE and CINAHL databases from January 1997 through May 2015, and reference lists of the selected articles to identify English-language randomized controlled trials and cohort studies of fracture risk. Two independent reviewers screened articles and assessed methodological quality using Risk of Bias assessment for randomized controlled trials and the Newcastle-Ottawa Scale for cohort studies. Fracture risk was estimated as pooled risk ratios using a random-effects model and inverse variance method.

Results

Of 1926 identified articles, 21 independent studies fulfilled our selection criteria. Similar fracture risk was observed in women treated and not treated with tamoxifen [pooled risk ratio (RR) 0.95; 95% confidence interval (CI) 0.84-1.07]. A 35% (95% CI 1.21-1.51) higher fracture risk was observed in the aromatase inhibitor group compared with the tamoxifen group. A 17% (95% CI 1.07-1.28) higher fracture risk was observed in the aromatase inhibitor group than the no aromatase inhibitor group. Compared with the tamoxifen group, aromatase inhibitor-associated fracture risk increased by 33% (pooled RR 1.33; 95% CI 1.21-1.47) during the tamoxifen/aromatase inhibitor treatment period, but did not increase (pooled RR 0.99; 95% CI 0.72-1.37) during the post-tamoxifen/aromatase inhibitor treatment period.

Conclusions

Fracture risk is significantly higher in women treated with aromatase inhibitors, especially during the treatment period. Tamoxifen is not associated with lower fracture risk while tamoxifen could potentially preserve bone mass. Better osteoporosis management programs, especially during the treatment period, are needed for this group of women.

Cancer Treatment and Bone Health

Considerable advances in oncology over recent decades have led to improved survival, while raising concerns about long-term consequences of anticancer treatments. In patients with breast or prostate malignancies, bone health is a major issue due to the high risk of bone metastases and the frequent prolonged use of hormone therapies that alter physiological bone turnover, leading to increased fracture risk. Thus, the onset of cancer treatment-induced bone loss (CTIBL) should be considered by clinicians and recent guidelines should be routinely applied to these patients. In particular, baseline and periodic follow-up evaluations of bone health parameters enable the identification of patients at high risk of osteoporosis and fractures, which can be prevented by the use of bone-targeting agents (BTAs), calcium and vitamin D supplementation and modifications of lifestyle. This review will focus upon the pathophysiology of breast and prostate cancer treatment-induced bone loss and the most recent evidence about effective preventive and therapeutic strategies.

Metastatic Bone Disease in the Era of Bone-Targeted Therapy: Clinical Impact

Advances in the diagnosis and treatment of tumors by surgery, chemotherapy, biotherapy, radiotherapy and other modalities have increased the survival of cancer patients over the last 20 years. As a consequence, bone now represents the third most common site of metastatic involvement after the lung and liver. Approximately 20–25% of patients with neoplastic disease develop clinically evident bone metastases (BMs) during the natural course of their illness, with a further 50% of such lesions being identified during autopsy. BMs are the major cause of morbidity in cancer patients because of their epidemiological and clinical impact. Pain is the most frequent symptom in about 75% of patients but other serious complications can also occur, such as pathological fractures, spinal cord compression, hypercalcemia and bone marrow suppression. These complications worsen the patient's general condition and reduce patients’ mobility, facilitating the development of lung infections, skin ulcers, deep vein thrombosis, etc., and ultimately reducing prognosis and quality of life. The frequency of serious complications depends on the site and type of lesions and the treatment administered. Over the last 10 years, the introduction of bisphosphonates for the treatment of patients with BMs has led to a marked decrease in the frequency of complications, thus improving quality of life and clinical outcome. Furthermore, progress in understanding the pathophysiology of bone metastases has resulted in the development of new bone-targeted molecules such as denosumab. We therefore felt it would be useful to report on the epidemiological, clinical and economic impact of bone disease in a cancer setting.

Breast cancer survivorship: state of the science

PURPOSE

Only recently has breast cancer survivorship earned formal recognition as a research discipline. Complicating survivorship research is the frequent overlap between aging and treatment sequelae. The ACS/ASCO 2016 Breast Cancer Survivorship Care Guideline (Guideline) reflects comprehensive literature review through April 2015, while the jointly sponsored, inaugural Cancer Survivorship Symposium in 2016 (Symposium) reflects ongoing research activity in the area. Together, these platforms provide an opportunity to examine the use of randomized trials and controlled studies in survivorship care research.

METHODS

All 236 citations from the Guideline and all 250 abstracts from the Symposium were reviewed independently by two authors and assigned to prospectively determined categories.

RESULTS

Guideline citations were most frequently reviews (n = 88, 37.3%) and non-randomized, non-controlled studies (n = 51, 21.6%). Thirty-seven (15.7%) randomized trials were cited. Only 9% of Guideline recommendations were based on randomized clinical trial evidence, while 64% were based on evidence level "0" (expert opinion, clinical practice, etc.). Symposium abstracts consisted largely of non-randomized, non-controlled studies (n = 113, 45.2%), with ten completed randomized trials (4%). Few Guideline citations or Symposium abstracts incorporated matched, cancer-free controls.

CONCLUSIONS

Based on the literature underlying the ASCO Guideline as well as a survey of the Cancer Survivorship Symposium abstracts, a significant proportion of the survivorship literature at least through 2015 consisted of non-randomized, non-controlled studies. To optimally address survivorship issues, cancer therapy sequelae need to be distinguished from normal aging in studies incorporating cancer-free controls, and randomized clinical trials are needed to inform intervention strategies.

A Prospective Observational Study on Effect of Short-Term Periodic Steroid Premedication on Bone Metabolism in Gastrointestinal Cancer (ESPRESSO-01)

BACKGROUND

A multicenter prospective observational study evaluated the effect of gastrointestinal cancer chemotherapy with short-term periodic steroid premedication on bone metabolism.

PATIENTS AND METHODS

Seventy-four patients undergoing chemotherapy for gastrointestinal cancer were studied. The primary endpoints were changes in bone mineral densities (BMDs) and metabolic bone turnover 16 weeks after initiation of chemotherapy. BMDs, measured by dual-energy x-ray absorptiometry, and serum cross-linked N-telopeptides of type I collagen (sNTX), and bone alkaline phosphatase (sBAP) were assessed for evaluation of bone resorption and formation, respectively.

RESULTS

In 74.3% (55/74) of the patients, BMDs were significantly reduced at 16 weeks relative to baseline. The percent changes of BMD were -1.89% (95% confidence interval [CI], -2.67% to -1.11%: p < .0001) in the lumbar spine, -2.24% (95% CI, -3.59% to -0.89%: p = .002) in the total hip, and -2.05% (95% CI, -3.11% to -0.99%: p < .0001) in the femoral neck. Although there was no significant difference in sNTX levels during 16 weeks (p = .136), there was a significant increase in sBAP levels (p = .010). Decreased BMD was significantly linked to number of chemotherapy cycles (p = .02). There were no significant correlations between changes in BMDs and the primary site of malignancy, chemotherapy regimens, total cumulative steroid dose, steroid dose intensity, and additive steroid usage.

CONCLUSION

Gastrointestinal cancer chemotherapy with periodic glucocorticoid premedication was associated with reduced BMD and increased sBAP levels, which were linked to number of chemotherapy cycles but independent of primary site, chemotherapy regimen, duration, and additive steroid usage. The Oncologist 2017;22:592-600 IMPLICATIONS FOR PRACTICE: Bone health and the management of treatment-related bone loss are important for cancer care. The present study showed that a significant decrease in bone mineral density (BMD) and an increase in serum bone alkaline phosphatase levels occurred in gastrointestinal cancer patients receiving chemotherapy, which were linked to number of chemotherapy cycles but were independent of primary site, chemotherapy regimen, total steroid dose, and steroid dose intensity. Surprisingly, it seems that the decreasing BMD levels after only 16 weeks of chemotherapy for gastrointestinal cancer were comparable to that of 12-month adjuvant aromatase inhibitor therapy for early-stage breast cancer patients.

Comparison of combined low-dose hormone therapy vs. tibolone in the prevention of bone loss

OBJECTIVES

To compare the effects on bone mineral density (BMD) measured by dual-energy X-ray absorptiometry at the lumbar spine, the femoral neck and the total hip following 2 years of treatment with a low-dose combined hormone therapy (HT) comprised of 1 mg estradiol and 0.5 mg norethisterone acetate (E2/NETA) versus 2.5 mg tibolone in postmenopausal women. Additionally, quantitative ultrasonometry (QUS) of the os calcaneus and of the phalanges was performed.

METHODS

Changes in BMD, QUS and side-effects were assessed at baseline, 6, 12 and 24 months in 50 postmenopausal women who received either E2/NETA (n = 26) or tibolone (n = 24) for 2 years.

RESULTS

Compared to women on tibolone, women receiving E2/NETA showed a significant increase in BMD from baseline to 12 and 24 months at the lumbar spine (3.07%, 3.86%; p < 0.01 vs. 1.13%, 2.23%; p < 0.05), and at the total hip (1.33%, 1.69%; p < 0.01 vs. 0.76%, 0.70%) and at the femoral neck from baseline to 24 months (1.10%; p < 0.05). QUS indices only showed a significant change with the ultrasound bone profile index with E2/NETA at 6 months (-2.32%; p < 0.001).

CONCLUSIONS

Low-dose E2/NETA showed a significantly higher increase in BMD compared to tibolone. QUS measurement was not considered to comprise beneficial effects in monitoring drug-induced bone changes.

Medication use trajectories of postmenopausal breast cancer survivors and matched cancer-free controls

While adverse medical sequelae are associated with breast cancer therapies, information on breast cancer impact on medication use is limited. Therefore, we compared medication use before and after diagnosis of early stage breast cancer to medication use in matched, cancer-free controls. Of 68,132 Women's Health Initiative participants, 3726 were diagnosed with breast cancer and, after exclusions, in 1731 breast cancer cases, medication use before and >3 years after diagnosis (mean 5.3 ± 2.1 SD) was compared to use in 1731 cancer-free matched controls on similar inventory dates. The medication category number at follow-up inventory was the primary study outcome. Medication category use (n, mean, SD) was comparable at baseline and significantly increased at follow-up in both cases (2.48 ± 1.66 vs. 4.15 ± 2.13, baseline vs follow-up, respectively, P < .0001) and controls (2.44 ± 1.67 vs. 3.95 ± 2.13, respectively, P < .0001), with clinically marginal but statistically significant additional medication category use by cases (0.20 ± 2.40, P < .0001). Tamoxifen users used somewhat more selected medication categories at follow-up assessment (mean 3.40 ± 1.89 vs. 3.21 ± 1.99, respectively, P = 0.05), while aromatase inhibitor users used more medication categories (mean 4.85 ± 2.10 vs. 4.44 ± 1.94, respectively, P = 0.02). No increase in medication category was seen in cases who were not current endocrine therapy users. Breast cancer survivors having only a clinically marginal increase in medication use compared to cancer-free controls. These findings highlight the importance of incorporation of control populations in studies of cancer survivorship.

Aromatase inhibitor treatment for breast cancer: short-term effect on bone health

Aim of this study

Aim of this study was to examine the effects of aromatase inhibitors (AIs), which are used in every phase of breast cancer treatment, on the bone mineral density (BMD) of patients with early-stage breast cancer.

Material and methods

Menopausal female patients who were diagnosed with stages 1–3 breast cancer and who were planned for anastrazole or letrozole as adjuvant therapy were examined. After the patients’ BMD was measured, 45 patients without osteoporosis were included in the study. Six months after AI therapy started, the patients’ BMD was measured again.

Results

In this study, we tried to show that there was a statistical difference in the BMD of 45 patients before and 6 months after treatment. Among all measurements (femur and lumbar T-scores), the femur Z-score (p = 0.52) was the only score that was not statistically significant. Statistical significance (p < 0.01) was detected in comparative analysis of the other measurements. According to this analysis, a significant loss of BMD was seen even in the first six months after AI treatment was introduced.

Conclusions

Female patients with breast cancer are at higher risk for bone loss and fractures than healthy women. In this study, we showed the negative effects on BMD of aromatase inhibitor therapy, one of the main contributions to osteoporosis in women with breast cancer. This study is the first to quantify the short-term effect of AI treatment on BMD in postmenopausal women with breast cancer.

Adjuvant bisphosphonates in early breast cancer: consensus guidance for clinical practice from a European Panel

Bisphosphonates have been studied in randomised trials in early breast cancer to investigate their ability to prevent cancer treatment-induced bone loss (CTIBL) and reduce the risk of disease recurrence and metastasis. Treatment benefits have been reported but bisphosphonates do not currently have regulatory approval for either of these potential indications. This consensus paper provides a review of the evidence and offers guidance to breast cancer clinicians on the use of bisphosphonates in early breast cancer. Using the nominal group methodology for consensus, a systematic review of the literature was augmented by a workshop held in October 2014 for breast cancer and bone specialists to present and debate the available pre-clinical and clinical evidence for the use of adjuvant bisphosphonates. This was followed by a questionnaire to all members of the writing committee to identify areas of consensus. The panel recommended that bisphosphonates should be considered as part of routine clinical practice for the prevention of CTIBL in all patients with a T score of <-2.0 or ≥2 clinical risk factors for fracture. Compelling evidence from a meta-analysis of trial data of >18,000 patients supports clinically significant benefits of bisphosphonates on the development of bone metastases and breast cancer mortality in post-menopausal women or those receiving ovarian suppression therapy. Therefore, the panel recommends that bisphosphonates (either intravenous zoledronic acid or oral clodronate) are considered as part of the adjuvant breast cancer treatment in this population and the potential benefits and risks discussed with relevant patients.

High levels at baseline of serum pyridinoline crosslinked carboxyterminal telopeptide of type I collagen are associated with worse prognosis for breast cancer patients

It is speculated that adjuvant use of bisphosphonate reduces recurrence in breast cancer patients through suppression of bone resorption. To determine the prognostic impact of bone resorption markers, we investigated serum levels of the pyridinoline crosslinked carboxyterminal telopeptide of type I collagen (1CTP) and N-terminal crosslinking telopeptides of type I collagen (NTX). 1CTP and NTX were measured at baseline (before operation or neoadjuvant therapies) and afterward in 469 patients operated on breast cancer. The optimal cutoff value of 1CTP for relapse-free survival (RFS) was set at 3.6 ng/ml with an area under the receiver operating characteristics curve of 0.641 [95% confidence interval (CI) = 0.560-0.721; p = 0.0011]. However, we were unable to determine a significant cutoff value for NTX. RFS was significantly worse for 1CTP-high patients with than for those with low levels of 1CTP (p = 0.0002). Multivariate analysis with tumor size, lymph node metastasis, and nuclear grade showed that 1CTP was a significant independent prognostic factor (hazard ratio = 2.04, 95% CI = 1.13-3.68; p = 0.018). Worse prognosis for the subset with high 1CTP levels applied only to postmenopausal patients (p = 0.0002). RFS of 130 patients whose 1CTP changed from low at baseline to high at 6 months postoperatively showed RFS almost as poor as that for patients with high 1CTP throughout. These findings suggest that 1CTP may be useful not only for identifying patients with unfavorable prognosis, but also for selecting patients who may benefit from administration of bone-modifying agents in an adjuvant setting.

Adjuvant Endocrine Therapy and Bone Health in Breast Cancer

Breast cancer is one of the most common malignancies of women. The majority of breast cancers express estrogen and/or progesterone receptors, permitting anticancer targeting strategies to reduce estrogen signaling in the cancer cells and thereby lowering the risk of breast cancer recurrence. The development of the selective estrogen receptor modulator (SERM) tamoxifen marked a significant milestone in breast cancer care that transcended older estrogen ablative strategies such as oophorectomy and ovarian irradiation. An unintended benefit of tamoxifen in postmenopausal women was bone density preservation. The third generation of aromatase inhibitors (AIs) have demonstrated superior efficacy to tamoxifen in improving disease-free survival in postmenopausal women. However, the AIs significantly increase bone resorption, reduce bone mineral density, and increase the risk of fracture above that of tamoxifen. As a consequence of this, clinical oncologists have assumed a larger role in the screening and treatment of the skeletal complications of breast cancer therapies. The key features of managing bone health in women with early stage breast cancer receiving adjuvant endocrine therapy are reviewed here.

Cancer treatment-induced bone loss (CTIBL): pathogenesis and clinical implications

Osteopenia and osteoporosis are often long-term complications of anti-neoplastic treatments, defined as "cancer treatment-induced bone loss" (CTIBL). This pathological condition in oncologic patients results in a higher fracture risk than in the general population, and so has a significant negative impact on their quality of life. Hormone treatment is the main actor in this scenario, but not the only one. In fact, chemotherapies, radiotherapy and tyrosine kinase inhibitors may contribute to deregulate bone remodeling via different mechanisms. Thus, the identification of cancer patients at risk for CTIBL is essential for early diagnosis and appropriate intervention, that includes both lifestyle modifications and pharmacological approaches to prevent bone metabolism failure during anti-tumor treatments.

Screening for osteoporosis after breast cancer: for whom, why and when

Osteoporosis and breast cancer are common diseases in postmenopausal women. Bone and the breast are both estrogenic dependent tissues and different surrogate markers for osteoporosis are opposite of those for the risk of breast cancer. In particular, numerous studies have reported a positive relationship between high bone mineral density (BMD) and a greater risk of breast cancer. On the other hand, most treatments in early breast cancer women including ovarian suppression treatments (chemotherapy, surgery or GnRH agonists) and aromatase inhibitor (AI) therapy induce a profound and rapid suppression of estrogen levels thereby increasing the rate of bone loss. Nevertheless, their impact on the risk of fracture is still questionable, especially in postmenopausal women with no osteoporosis at baseline. The purpose of this minireview is to examine the relationship between breast cancer and the risk of fracture and to discuss a screening strategy for osteoporosis after breast cancer.

Effect of anastrozole on hormone levels in postmenopausal women with early breast cancer

OBJECTIVES

The aim of this study was to investigate the influence of anastrozole on serum hormone levels in postmenopausal women with hormone receptor-positive breast cancer.

METHODS

We prospectively determined serum levels of estradiol, testosterone, dehydroepiandrosterone sulfate (DHEAS), sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH) and luteinizing hormone (LH) at screening, as well as after 12 and 24 months of treatment and studied the associations with markers of bone turnover and bone mineral density (BMD).

RESULTS

Altogether, a full set of hormone levels was available for 70 patients. Anastrozole treatment led to decreases of 92.1% for estradiol and 11.1% for LH over the observation period (p < 0.001). Conversely, FSH, DHEAS and testosterone concentrations increased by 5.9%, 33.3% and 50%, respectively (p < 0.001). SHBG levels remained stable during the 24 months of treatment (p = 0.355). There were modest associations between FSH, SHBG, CrossLaps and N-terminal propeptide of human procollagen type I (p < 0.05). Moreover, SHBG correlated positively with the BMD of femoral neck, total hip, total hip T-score, lumbar spine and the lumbar spine T-score, whereas FSH and estradiol correlated with the lumbar spine T-score (p < 0.05).

CONCLUSIONS

During the 24 months of follow-up, treatment with anastrozole decreased the serum levels of estradiol and LH. Furthermore, we found notable increases of serum levels of FSH, DHEAS and testosterone in the first 12 months of treatment, stabilizing thereafter. Additionally, we were able to correlate hormone levels with markers of bone turnover and BMD for the first time in this regard.

Supportive care considerations for older adults with cancer

The treatment of cancer presents specific concerns that are unique to the growing demographic of elderly patients. Because the incidence of cancer is strongly correlated with aging, the expansion of supportive care and other age-appropriate therapies will be of great importance as the population of elderly patients with cancer increases in the coming years. Elderly patients are especially likely to experience febrile neutropenia, complications from chemotherapy-induced nausea, anemia, osteoporosis (especially in patients diagnosed with breast or prostate cancer), depression, insomnia, and fatigue. These issues are often complicated by other chronic conditions related to age, such as diabetes and cardiac disease. For many patients, symptoms may be addressed both through lifestyle management and pharmaceutical approaches. Therefore, the key to improving quality of life for the elderly patient with cancer is an awareness of their specific needs and a familiarity with emergent treatment options.

Fracture incidence after 3 years of aromatase inhibitor therapy

BACKGROUND

The purpose of this study was to describe the fracture incidence and bone mineral density (BMD) evolution in a large cohort of post-menopausal women with breast cancer after 3 years of aromatase inhibitor (AI) therapy.

PATIENTS AND METHODS

A prospective, longitudinal study in real-life setting. Each woman had an extensive medical assessment, a biological evaluation, a BMD measurement, and systematic spinal X-rays at baseline and after 3 years of AI therapy. Women with osteoporosis at baseline (T-score < -2.5 and/or non-traumatic fracture history) were treated by oral weekly bisphosphonates.

RESULTS

Among 497 women (mean age 63.8 ± 9.6 years) included in this study, 389 had a bone evaluation both at baseline and after 3 years of AI therapy: 267 women (mean age 61.2 ± 8.6) with no osteoporosis at baseline and 122 women (mean age 67.2 ± 9.1) with osteoporosis at baseline justifying a weekly oral bisphosphonate treatment. Women without bisphosphonates had a significant decrease in spine BMD (-3.5%, P < 0.01), neck BMD (-2.0%, P < 0.01), and total hip BMD (-2.1%, P < 0.01) over the 3 years but only 15 of them (5.6%) presented an incident vertebral or non-vertebral fracture. In osteoporotic women treated with bisphosphonates, spine and hip BMD were maintained at 3 years but 12 of them (9.8%) had an incident fracture. These fractured women were significantly older (74.1 ± 9.8 versus 66.5 ± 8.8) but also presented BMD loss during treatment suggesting poor adherence to bisphosphonate treatment.

CONCLUSION

This real-life study confirmed that AIs induced moderate bone loss and low fracture incidence in post-menopausal women without initial osteoporosis. In women with baseline osteoporosis and AI therapy, oral bisphosphonates maintain BMD but were associated with a persistent fracture risk, particularly in older women.

Effects of adjuvant exemestane versus anastrozole on bone mineral density for women with early breast cancer (MA.27B): a companion analysis of a randomised controlled trial

BACKGROUND

Treatment of breast cancer with aromatase inhibitors is associated with damage to bones. NCIC CTG MA.27 was an open-label, phase 3, randomised controlled trial in which women with breast cancer were assigned to one of two adjuvant oral aromatase inhibitors-exemestane or anastrozole. We postulated that exemestane-a mildly androgenic steroid-might have a less detrimental effect on bone than non-steroidal anastrozole. In this companion study to MA.27, we compared changes in bone mineral density (BMD) in the lumbar spine and total hip between patients treated with exemestane and patients treated with anastrozole.

METHODS

In MA.27, postmenopausal women with early stage hormone (oestrogen) receptor-positive invasive breast cancer were randomly assigned to exemestane 25 mg versus anastrozole 1 mg, daily. MA.27B recruited two groups of women from MA.27: those with BMD T-scores of -2·0 or more (up to 2 SDs below sex-matched, young adult mean) and those with at least one T-score (hip or spine) less than -2·0. Both groups received vitamin D and calcium; those with baseline T-scores of less than -2·0 also received bisphosphonates. The primary endpoints were percent change of BMD at 2 years in lumbar spine and total hip for both groups. We analysed patients according to which aromatase inhibitor and T-score groups they were allocated to but BMD assessments ceased if patients deviated from protocol. This study is registered with ClinicalTrials.gov, NCT00354302.

FINDINGS

Between April 24, 2006, and May 30, 2008, 300 patients with baseline T-scores of -2·0 or more were accrued (147 allocated exemestane, 153 anastrozole); and 197 patients with baseline T-scores of less than -2·0 (101 exemestane, 96 anastrozole). For patients with T-scores greater than -2·0 at baseline, mean change of bone mineral density in the spine at 2 years did not differ significantly between patients taking exemestane and patients taking anastrozole (-0·92%, 95% CI -2·35 to 0·50 vs -2·39%, 95% CI -3·77 to -1·01; p=0·08). Respective mean loss in the hip was -1·93% (95% CI -2·93 to -0·93) versus -2·71% (95% CI -4·32 to -1·11; p=0·10). Likewise for those who started with T-scores of less than -2·0, mean change of spine bone mineral density at 2 years did not differ significantly between the exemestane and anastrozole treatment groups (2·11%, 95% CI -0·84 to 5·06 vs 3·72%, 95% CI 1·54 to 5·89; p=0·26), nor did hip bone mineral density (2·09%, 95% CI -1·45 to 5·63 vs 0·0%, 95% CI -3·67 to 3·66; p=0·28). Patients with baseline T-score of -2·0 or more taking exemestane had two fragility fractures and two other fractures, those taking anastrozole had three fragility fractures and five other fractures. For patients who had baseline T-scores of less than -2·0 taking exemestane, one had a fragility fracture and four had other fractures, whereas those taking anastrozole had five fragility fractures and one other fracture.

INTERPRETATION

Our results demonstrate that adjuvant treatment with aromatase inhibitors can be considered for breast cancer patients who have T-scores less than -2·0.

FUNDING

Canadian Cancer Society Research Institute, Pfizer, Canadian Institutes of Health Research.

Aromatase inhibitors in the breast cancer clinic: focus on exemestane

Breast cancer is the most prevalent type of cancer in women and responsible for significant female cancer-related mortality worldwide. In the Western world, over 80% of breast cancers are hormone-receptor positive for which endocrine therapy is administered. The main anti-estrogen treatments in use consist of selective estrogen-receptor modulators, such as tamoxifen, and third-generation aromatase inhibitors (AIs), such as exemestane, letrozole, and anastrozole. In this review, the focus will lie on exemestane, its clinical use, and its side-effect profile. Exemestane is the only third-generation steroidal AI. Its efficacy as a first-line treatment in metastatic breast cancer has been demonstrated. Therefore, exemestane could be considered a valid first-line therapeutic option, but it also can be used in second-line or further situations. Exemestane is mostly used as part of sequential adjuvant treatment following tamoxifen, but in this setting it is also active in monotherapy. Furthermore, this AI has been studied in the neoadjuvant setting as presurgical treatment, and even as chemoprevention in high-risk healthy postmenopausal women. It may reverse side effects of tamoxifen, such as endometrial changes and thromboembolic disease but may also cause some inconvenient side effects itself. Additionally, there is a lack of total cross-resistance between exemestane and nonsteroidal AIs as far as their anti-tumoral efficacy is concerned; moreover the two classes of AIs display a nontotal overlapping toxicity profile. Taking together, exemestane can be considered as a useful treatment option at all stages of breast cancer.

Skeletal manifestations of treatment of breast cancer

Breast cancer and osteoporosis are common diagnoses in women. Breast cancer survival has improved due to earlier detection and improved treatments. As most breast cancers are estrogen receptor positive, treatment is often aimed at altering the hormonal environment. Both pre and postmenopausal women undergoing these therapies are at risk for bone loss. The patient's health care team ought to have an awareness of the potential for breast cancer treatments to accelerate bone loss. Women with early stage breast cancer are treated with curative intent and, therefore, maintaining bone health is important and is part of the survivorship care to ensure an optimal quality of life.

[Treatment effect of breast cancer and prostate cancer on bone]

Aromatase inhibitors are used in the treatment of breast cancer and androgen deprivation therapy is used in prostate cancer. Both of them induce bone loss and increase fracture incidence. Early detection is important for patients with increased risk of osteoporotic fractures. In this article we review the available treatments and their indication to prevent the onset of osteoporosis and osteoporotic fractures in this patient group.

A multicenter prospective study to evaluate bone fracture related to adjuvant anastrozole in Japanese postmenopausal women with breast cancer: two-year interim analysis of Saitama Breast Cancer Clinical Study Group (SBCCSG-06)

BACKGROUND

Because of its superior efficacy to tamoxifen, anastrozole has been widely used in Japan as an adjuvant treatment for postmenopausal, hormone-responsive breast cancer patients. However, anastrozole may affect bone in Japanese patients similar to its effects in Western patients. The aim of this study is to evaluate the rate of bone fracture and bone mineral density (BMD) during anastrozole treatment in Japanese patients.

PATIENTS AND METHODS

In this study, 350 postmenopausal women with hormone-responsive, stage I to IIIA breast cancer were enrolled and scheduled to receive adjuvant anastrozole treatment for up to 5 years. Patients underwent clinical examination for bone fractures and annual measurement of BMD during treatment.

RESULTS

After a median follow-up of 33.0 months, bone fractures occurred in 1.8 %. Annual fracture rates were 0.3 and 1.2 % during the first and second year, respectively. The overall median BMD significantly decreased, measuring 87.5, 84.3, and 83.5 % at baseline and after 1 and 2 years, respectively. Musculoskeletal disorders were the most common (26.1 %), and hot flashes were the second most common adverse event (7.9 %). Severe adverse events occurred in 5.5 % of all the cases.

CONCLUSIONS

In this interim analysis, the bone fracture rate was lower than that in the Western population despite a significant reduction of BMD after 2 years of treatment with anastrozole. Adjuvant anastrozole treatment was well tolerated in Japanese postmenopausal women with breast cancer. Long-term follow-up data is necessary to elucidate the racial disparities of the safety profile of anastrozole.

Bisphosphonates in the adjuvant treatment of breast cancer

Bisphosphonates, as potent inhibitors of osteoclast-mediated bone resorption, significantly reduce the risk of skeletal complications in metastatic bone disease and also prevent cancer treatment-induced bone loss (CTIBL). However, more recently, there has been increasing data indicating that bisphosphonates exhibit anti-tumour activity, possibly via both indirect and direct effects, and can potentially modify the metastatic disease process providing more than just supportive care. The evidence from previous studies of an anti-tumour effect of bisphosphonates was inconclusive, with conflicting evidence from adjuvant oral clodronate trials. However, more recent trials using zoledronic acid have shown benefits in terms of disease-free and overall survival outcomes in certain subgroups, most evidently in older premenopausal women with hormone-sensitive disease treated with ovarian suppression, and in women in established menopause at trial entry. In the adjuvant setting, the use of bisphosphonates has also been focused on the prevention and treatment of CTIBL and recent guidelines have defined treatment strategies for CTIBL. The role of bisphosphonates in CTIBL in early breast cancer is well defined. There have been mixed results from large adjuvant metastasis-prevention studies of bisphosphonates, but there are strong signals from large subgroups analyses of randomised phase III trials suggesting significant anti-tumour beneficial effects in specific patient populations.