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

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.