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

The tamoxifen paradox-influence of adjuvant tamoxifen on fracture risk in pre- and postmenopausal women with breast cancer

Our data demonstrate that tamoxifen does not reduce fracture risk. Close surveillance is necessary to prevent bone loss in premenopausal women with breast cancer upon treatment initiation.

INTRODUCTION

Endocrine treatment of breast cancer may interfere with bone turnover and influence fracture risk.

METHODS

Out of a cohort of almost 5 million patients in total, we identified 5520 women between 18 and 90 years of age with breast cancer receiving tamoxifen, matched them with 5520 healthy controls using the Disease Analyzer Database, and investigated the fracture risk.

RESULTS

We found a cumulative incidence of fractures of 6.3% in patients aged between 18 and 50 years (n = 3634) treated with tamoxifen versus a cumulative incidence of 3.6% in the control group (p < 0.001). As such, the risk of fracture was 75% higher for patients receiving tamoxifen than that for healthy controls (HR 1.75; 95% CI 1.25-2.48). With regard to patients aged between 55 and 90 years (n = 7406), the cumulative incidence of fractures in patients treated with tamoxifen was 10.1% compared to 9.3% in the control group (p = 0.740), i.e., there was no significant difference between the two groups (HR 0.97; 95% CI 0.81-1.16).

CONCLUSIONS

Compared to healthy controls, premenopausal women with breast cancer treated with tamoxifen showed an increased risk of fracture, while postmenopausal women on tamoxifen did not show any risk reduction.

Effect of denosumab administration on low bone mineral density (T-score -1.0 to -2.5) in postmenopausal Japanese women receiving adjuvant aromatase inhibitors for non-metastatic breast cancer

Although adjuvant aromatase inhibitor (AI) therapy is widely used in postmenopausal women with hormone receptor-positive breast cancer, it is known to be associated with bone loss and increased fracture risk. Denosumab, a fully human monoclonal antibody against the receptor activator of nuclear factor-κB ligand, has been shown to protect against AI-induced bone loss. However, the efficacy of denosumab in the treatment of AI-associated bone loss has not been prospectively evaluated in Japan. We prospectively monitored bone mineral density (BMD) of the lumbar spine and bilateral femoral necks in 100 postmenopausal women with hormone receptor-positive postoperative breast cancer of clinical stage I-IIIA in whom treatment with AI as adjuvant endocrine therapy was planned or had been ongoing. Study participants received supplemental calcium and vitamin D every day and denosumab (60 mg) subcutaneously every 6 months. At enrollment, patients were required to have evidence of low bone mass without meeting the criteria for osteoporosis. The primary endpoint was percentage change from baseline in lumbar spine BMD at month 12. At 6 and 12 months, lumbar spine BMD increased by 3.3 and 4.7%, respectively. BMD of the femoral necks also increased. Hypocalcemia of grade ≥2, osteonecrosis of the jaw, and non-traumatic clinical fracture did not occur. In conclusion, semi-annual treatment with denosumab was associated with increased BMD in Japanese women receiving adjuvant AI therapy, regardless of prior AI treatment.

Bone health during endocrine therapy for cancer

Preservation of bone health remains a long-term clinical challenge in patients with breast and prostate cancer. Osteoporosis, defined by a loss of bone mass and microarchitecture, often results in fragility fractures that are typically associated with a high socioeconomic burden. Endocrine therapy, a mainstay treatment in the management of patients with hormone-sensitive breast and prostate cancer in the adjuvant setting, commonly exerts adverse effects on the musculoskeletal system and is associated with an increased risk of osteoporosis and fractures. Adjuvant use of gonadotropin-releasing hormone analogues, which can also be used in metastatic disease, in combination with tamoxifen in premenopausal women, and aromatase inhibitors in postmenopausal women with hormone-sensitive breast cancer, causes rapid bone loss and fragility fractures. By contrast, selective oestrogen receptor modulators, such as tamoxifen, have bone-protective effects in postmenopausal women. In men with castration-sensitive prostate cancer, androgen deprivation is achieved with drugs that lower gonadotropin levels, and these drugs can be combined with androgen receptor antagonists. These therapies induce a high bone turnover with rapid bone loss that is reminiscent of the changes occurring in early menopause and result in an increased risk of fracture. In this Review, we describe how adjuvant endocrine therapies of breast and prostate cancer impair bone health and outline evidence from randomised controlled trials of strategies to reduce risk of fracture.

FRAX Calculated without BMD Resulting in a Higher Fracture Risk Than That Calculated with BMD in Women with Early Breast Cancer

BACKGROUND AND PURPOSE

The aim of this study was to investigate the importance of including the measurement of bone mineral density (BMD) in reliable fracture risk assessment for women diagnosed with early nonmetastatic breast cancer (EBC) before AI treatment if zoledronic acid is not an option.

MATERIAL AND METHODS

One hundred and sixteen women with EBC were included in the study before initiating AI treatment. Most participants were osteopenic. The 10-year probability of hip fracture and major osteoporotic fracture was calculated with and without BMD based on clinical information collected at baseline using the fracture risk assessment (FRAX) tool. To compare data, the nonparametric tests were used.

RESULTS

There was a significant difference (p<0.001) in the number of high-risk and low-risk FRAX score of hip fracture between before and after including BMD values. The high-risk category decreased by 50.9%, while the low-risk category increased by 42.9%. In FRAX score of major osteoporotic the findings were similar (p<0.001): The high-risk and moderate-risk category decreased by 70.4% and 4.9%, respectively, while the low-risk category increased by 43.8% when including BMD value. When stratified by age, patients aged 65 years or older were at a significantly (p<0.001) higher risk of suffering a hip or major osteoporotic fracture, highlighting the importance of including BMD measurements in this age group.

CONCLUSIONS

Our data support that DXA scanning of women with EBC should be performed to avoid overestimation of osteoporosis before AI treatment. It is particularly important in patients older than 65 years of age and when zoledronic acid is not an option.

Prevention of breast cancer treatment-induced bone loss in premenopausal women treated with zoledronic acid: Final 5-year results from the randomized, double-blind, placebo-controlled ProBONE II trial

PURPOSE

Premenopausal women receiving chemotherapy or endocrine treatment for early breast cancer are at increased risk for cancer treatment induced bone loss (CTIBL). The aim of the randomized, double-blind ProBONE II trial was to investigate whether a 2-year adjuvant treatment with 4 mg intravenous zoledronic acid (ZOL) every 3 months versus placebo would prevent CTIBL after a five-year period.

METHODS

Thirty-one of the 34 participants in the ZOL arm and thirty-four of the 36 participants in the placebo arm were followed-up to the 5-year visit and completed the study as planned. The changes in Bone Mass Density (BMD) were assessed at baseline and each visit after treatment initiation.

RESULTS

After 24 months, BMD at the lumbar spine showed a 2.9% increase in patients treated with ZOL vs. a 7.1% decrease in placebo-treated participants compared to baseline (p < 0.001). Over the 60-month study period, we found a decrease of 2.2% vs. 7.3% in the BMD at the lumbar spine in patients receiving ZOL and placebo respectively (p < 0.001). Over the 60-month study period, BMD in the placebo arm showed a continuous decrease at all sites (p < 0001), whereas patients treated with ZOL reached baseline BMD-values at the femoral neck and total hip.

CONCLUSIONS

In ProBone II, a 2-year treatment with ZOL 4 mg intravenous every 3 months prevented cancer treatment induced bone loss in premenopausal women with breast cancer and maintained the BMD up to 3 years post-treatment.

Assessment and management of bone health in women with oestrogen receptor-positive breast cancer receiving endocrine therapy: Position statement of the Endocrine Society of Australia, the Australian and New Zealand Bone & Mineral Society, the Australasian Menopause Society and the Clinical Oncology Society of Australia

To formulate clinical consensus recommendations on bone health assessment and management of women with oestrogen receptor-positive early breast cancer receiving endocrine therapy, representatives appointed by relevant Australian Medical Societies used a systematic approach for adaptation of guidelines (ADAPTE) to derive an evidence-informed position statement addressing 5 key questions. Women receiving adjuvant aromatase inhibitors and the subset of premenopausal woman treated with tamoxifen have accelerated bone loss and increased fracture risk. Both bisphosphonates and denosumab prevent bone loss; additionally, denosumab has proven antifracture benefit. Women considering endocrine therapy need fracture risk assessment, including clinical risk factors, biochemistry and bone mineral density (BMD) measurement, with monitoring based on risk factors. Weight-bearing exercise, vitamin D and calcium sufficiency are recommended routinely. Antiresorptive treatment should be considered in women with prevalent or incident clinical or morphometric fractures, a T-score (or Z-scores in women <50 years) of <-2.0 at any site, or if annual bone loss is ≥5%, considering baseline BMD and other fracture risk factors. Duration of antiresorptive treatment can be individualized based on absolute fracture risk. Relative to their skeletal benefits, risks of adverse events with antiresorptive treatments are low. Skeletal health should be considered in the decision-making process regarding choice and duration of endocrine therapy. Before and during endocrine therapy, skeletal health should be assessed regularly, optimized by nonpharmacological intervention and where indicated antiresorptive treatment, in an individualized, multidisciplinary approach. Clinical trials are needed to better delineate long-term fracture risks of adjuvant endocrine therapy and to determine the efficacy of interventions designed to minimize these risks.

Pituitary Diseases and Bone

Neuroendocrinology of bone is a new area of research based on the evidence that pituitary hormones may directly modulate bone remodeling and metabolism. Skeletal fragility associated with high risk of fractures is a common complication of several pituitary diseases such as hypopituitarism, Cushing disease, acromegaly, and hyperprolactinemia. As in other forms of secondary osteoporosis, pituitary diseases generally affect bone quality more than bone quantity, and fractures may occur even in the presence of normal or low-normal bone mineral density as measured by dual-energy X-ray absorptiometry, making difficult the prediction of fractures in these clinical settings. Treatment of pituitary hormone excess and deficiency generally improves skeletal health, although some patients remain at high risk of fractures, and treatment with bone-active drugs may become mandatory. The aim of this review is to discuss the physiological, pathophysiological, and clinical insights of bone involvement in pituitary diseases.

Osteoporosis and musculoskeletal complications related to therapy of breast cancer

Aromatase inhibitors (AIs) are the treatment of choice for the majority of postmenopausal women with estrogen receptor (ER) positive breast cancers in early and advanced stage settings. One of most frequent side effects of AIs is bone loss that is of sufficient magnitude to increase risk of osteoporotic fractures. Osteoporosis is primarily a complex genetic disease with few modifiable risk factors. As the lifespan increases, and breast mortality decreases, more women with breast cancer will be at risk of osteoporotic fractures, or falls that result in fractures. The screening, prevention, and treatment of osteoporosis do not differ in women with or without breast cancer. Rather, breast cancer treatments, including AIs, chemotherapy-induced ovarian failure, and gonadotropin-releasing hormone (GnRH) agonists, all decrease estrogen, which causes net bone resorption, leading some women to experience fracture. Occurring in about fifty-percent of women, AI-induced arthralgia is one of the most common side effects, and causes of nonadherence and discontinuation. Registry studies show that nonadherence and discontinuation may contribute to higher breast cancer mortality. Thus, understanding the mechanisms, risk factors, and interventions to mitigate symptoms of AI-induced arthralgia is a high priority.

Toxicity of Cancer Therapies in Older Patients

PURPOSE OF THE REVIEW

In clinical practice, older patients are often undertreated due to underrepresentation in clinical trials and fear of toxicity. Our objective was therefore to review toxicities that are specific to older cancer patients, to review risk factors in order to help physicians guide their decisions, and to review interventions that can be implemented in routine clinical practice to prevent toxicity induced by cancer therapies.

RECENT FINDINGS

On the whole, reviews report similar number and frequency as well as similar grade 3 or 4 adverse events between subjects older and younger than 65 years. Yet patients included in clinical trials are often not representative of real-life patients and are often fit older cancer patients. Moreover, tolerance to the additive impact of multiple adverse effects is different between older and younger patients. And specific symptoms such as stomatitis may cause a series of consequences such as dehydration, denutrition, renal insufficiency, and adverse events of renally excreted drugs. Older patients are at high risk of toxicity due to many factors but mainly due to the prevalence of frailty in this population that has been estimated to be around 40% increasing the risk of chemotherapy intolerance. As a consequence, interventions must be implemented according to altered domains of comprehensive geriatric assessment in order to improve anticancer tolerance. These interventions are reviewed here.

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.

Significant improvement of bone mineral density by denosumab treatment in Japanese osteoporotic patients following breast cancer treatment

Background

The aim of this study was to evaluate the effects of denosumab in patients with osteoporosis (OP) and non-metastatic breast cancer following treatment of 1) surgery, 2) surgery and aromatase inhibitors, and 3) surgery, aromatase inhibitors, and anti-cancer agents, compared with those in primary OP patients.

Patients and methods

In this retrospective 24-month study, patients were divided into the primary OP group (34 cases) or OP receiving breast cancer treatment group (breast cancer group; 17 cases). We measured serum calcium, whole parathyroid hormone (PTH), 1,25OH₂D₃, bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase-5b (TRACP-5b), and bone mineral density (BMD) of the lumbar 1-4 vertebrae (L-BMD) and bilateral total hips (H-BMD) for 24 months.

Results

The percent changes of serum calcium in the breast cancer group were significantly lower than those in the primary OP group at 1 week, 1 and 12 months. The percent changes of whole PTH in the primary OP group were significantly lower than those in the breast cancer group at 2 and 4 months. Significant differences were found between the groups at 18 months (-34.5% in the primary OP group and -52.6% in the breast cancer group, respectively) for the percent changes of BAP. Significant differences were found between the groups at 12, 18, and 24 months (-39.7% in the primary OP group and -64.0% in the breast cancer group at 24 months, respectively) for the percent changes of TRACP-5b. The percent changes of L-BMD and H-BMD were significantly increased at 12, 18, and 24 months in both the primary OP group (7.0% and 4.7% at 24 months, respectively) and breast cancer group (8.0% and 5.4% at 24 months, respectively), compared with pre-treatment levels. Significant differences were not found between the groups for the percent changes of L-BMD and H-BMD.

Conclusion

Denosumab significantly increased L-BMD and H-BMD to comparable degrees in both groups; therefore, it represents a good therapeutic option for OP receiving breast cancer treatment as well as primary OP. Also, vitamin D supplementation is required due to the potential hypocalcemia, and estrogen may be responsible for the decrease of serum calcium in the breast cancer patients.

Bone: best papers of the year 2017

An overview of selected papers related to bone published in 2017 is provided.

PURPOSE

This paper accompanies a lecture at the 2018 Belgian Bone Club annual Clinical Update Symposium held in Brussels on January 20th, discussing the best papers (in the opinion of the author) published in the previous year.

METHODS

A PubMed search using the keyword "bone" and articles published in 2017.

RESULTS

Hot topics include screening for osteoporosis, novel anabolic drugs such as romosozumab and abaloparatide for osteoporosis and rare metabolic bone diseases, as well as long-term efficacy of denosumab and possible risk of multiple vertebral fractures following its discontinuation. Other selected articles cover effectiveness of bisphosphonates and changes in mineralization after long-term use, new guidelines for glucocorticoid- and aromatase inhibitor-induced osteoporosis, increasing use of high-dose vitamin D supplements despite lack of evidence for their widespread high-dose use, and cardiovascular safety concerns surrounding the use of calcium supplements. Other topics discussed are effects of diabetes on bone health, reciprocal crosstalk between bone cells and adipose tissue, and resistance exercise training to prevent bone loss and sarcopenia.

CONCLUSIONS

These papers offer a hopeful outlook for a better treatment and management of patients with osteoporosis and other metabolic bone diseases anno 2018.

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.

Fractures frequently occur in older cancer patients: the MD Anderson Cancer Center experience

PURPOSE AND INTRODUCTION

A growing number of cancer patients are older adults aged 65 years and older. Patients with cancer are at increased risk for developing osteoporosis, falls, and fractures. We sought to identify the incidence of fractures in older adults who underwent cancer care between January 2013 and December 2015.

METHODS

A comprehensive geriatric assessment was performed, and bone densitometry was measured at baseline, with a 2-year follow-up.

RESULTS

In this study, among 304 patients with gastrointestinal, urologic, breast, lung, and gynecologic cancers we evaluated, and who completed the bone density testing (n = 199), 80% had osteoporosis or low bone mass (osteopenia). There was a higher prevalence of osteoporosis in cancer patients (40 vs. 16%, p = 0.05) than in population studies. Vitamin D insufficiency (< 30 ng/ml) was identified in 49% of tested cases (n = 245). Risk factors for low bone mass or osteoporosis were advanced age (p = 0.05), malnutrition (p = 0.04), and frailty (p = 0.01). Over the following 2 years (median follow-up 18 months), there was an incidence of fractures of 110 per 1000 person-years, or 2.8 times higher than reported in individuals without cancer. Risk factors for fractures included advanced age (70-79 vs. 60-69 years, p = 0.05) and frailty (p = 0.03).

CONCLUSION

Most older cancer patients studied have osteoporosis or low bone mass, resulting in an almost 3-fold increase in fracture risk as compared to epidemiologic studies. Bone health issues are commonly seen in older cancer patients, we recommend universal bone density testing. The initiation of antiresorptive treatment when findings are of osteopenia or osteoporosis will reduce the risk of fractures.

Update on osteoporosis treatment

Treatment of osteoporosis should be directed primarily towards secondary prevention of fractures. The occurrence of drug-related adverse effects for the treatment of osteoporosis has led to a reevaluation of the indications, the duration of treatment and even withdrawal of some drugs from the market. This review has been made from different patient profiles that practitioners will find in usual practice; from patients with hip fracture with cognitive impairment, limitation of their day-to-day living activities and comorbidities, to active patients without any limitations; patients with vertebral fractures and non-vertebral fractures where secondary prevention is highly important. In general, antiresorptive drugs (alendronate and risedronate) will be the first choice. Zoledronate or denosumab will be indicated in cases of digestive intolerance, poor adherence or an increased risk of hip fracture. Teriparatide will be indicated to patients with 2or more previous vertebral fractures or very low bone density.

Adverse bone effects of medications used to treat non-skeletal disorders

There is a growing list of medications used to treat non-skeletal disorders that cause bone loss and/or increase fracture risk. This review discusses glucocorticoids, drugs that reduce sex steroids, antidiabetic agents, acid-reducing drugs, selective serotonin reuptake inhibitors, and heparin. A number of drugs are known to cause bone loss, increase fracture risk, or both. These drugs should be used in the lowest dose necessary to achieve the desired benefit and for the shortest time necessary, but in many cases, long-term treatment is required. Effective countermeasures are available for some.

Evaluation and management of skeletal disease in cancer care

Recently, there have been considerable advancements in cancer therapies thereby prolonging the life of cancer survivors. However, these recent advancements present new challenges in the management of bone disease in cancer survivors. Bone acts as a fertile soil for cancer seeding and bone health is often compromised because of increased inflammatory cytokines in cancer, direct cancer metastasis and toxic effects of anti-cancer therapies. This effect is more pronounced in elderly population who already have compromised bone mineral density leading to increased skeletal related events and bone pain. Timely diagnosis and effective interventions are essential for reducing bone-related morbidity in cancer survivors. Also, a complex interdependence exists between cancer related bone disease and tumor growth, creating a vicious circle of extensive bone destruction and cancer progression. Hence, maintenance of bone health and integrity plays a pivotal role in comprehensive cancer care. The bone-targeted treatments have been shown to preserve bone health, and modify the course of the underlying cancer. Management of long-term bone health requires a broad knowledge base that endocrinologists, oncologists and other care team members should be aware of. The manuscript highlights the skeletal effects of cancer, adjuvant therapies used for hormone-responsive cancers, chemotherapy induced bone loss and steps for accurate diagnosis and management of bone disease in cancer survivors by bridging the gaps in the comprehensive cancer care.