Medication-related osteonecrosis of the jaw (MRONJ) is primarily an adverse side effect of denosumab or bisphosphonates (particularly when used at high doses to prevent skeletal-related events [SREs] in patients with cancer and bone metastases) or possibly anti-angiogenic cancer treatment. While the implementation of preventive measures over recent years has reduced the risk of MRONJ in patients with bone metastases due to cancer, it is imperative to balance the risk of MRONJ against the beneficial effects of treatment with denosumab or bisphosphonates on the skeletal health of patients. Despite growing awareness of MRONJ within the medical community, there is a lack of large-scale, prospective clinical studies in this rapidly evolving field. Discussing preventive measures with patients and implementing them, both before and during treatment with bisphosphonates or denosumab, is the best option to reduce the risk of MRONJ. In particular, avoiding bone trauma and preventing and treating dental infections before and during denosumab or bisphosphonate therapy is crucial to minimize the risk of MRONJ. If MRONJ develops, conservative (non-surgical) treatment can provide symptom relief, but achieving mucosal closure remains challenging. When management of symptoms and mucosal healing are the ultimate goals of therapy, or after failure of conservative treatment, a surgical approach may be beneficial. This critical review, based on a best-evidence review of currently available literature, provides clear practical guidelines to help to prevent, manage and treat MRONJ. Overall, a multidisciplinary, pragmatic approach to MRONJ should be adopted, prioritizing patient's quality of life and management of their skeletal malignant disease.

Skeletal complications caused by osteoporosis or bone metastases are associated with considerable pain, increased mortality, and reduced quality of life. Furthermore, such events place a burden on health care resources. Agents that prevent bone resorption, such as bisphosphonates or denosumab, can reduce the risk of skeletal-related events and are widely used in patients with osteoporosis or bone metastases of cancer. Medication-related osteonecrosis of the jaw (MRONJ) is a rare, but potentially serious, adverse event associated with high cumulative doses of bisphosphonates or denosumab. However, MRONJ can be treated, and the likelihood of the development of this condition can be reduced through prophylactic dental care and the maintenance of good oral hygiene. Dentists, as part of a multiprofessional team, have a critical role in preventing MRONJ. This review describes the incidence and pathophysiology of MRONJ and provides guidance for dental practitioners with regard to the screening, prophylactic treatment, diagnosis, and management of patients with this condition. (Oral Surg Oral Med Oral Pathol Oral Radiol 2019;127:117À135) Medication-related osteonecrosis of the jaw (MRONJ) is an uncommon condition that can occur after exposure to agents used to prevent bone complications, such as bisphosphonates or denosumab, or treatment with other agents, such as angiogenesis inhibitors. 1 In the majority of cases, MRONJ manifests as exposed bone in the maxillofacial region (Figure 1), although non-exposed MRONJ has also been recognized (Figure 2). 2-5 Bisphosphonates and denosumab are predominantly used to reduce the risk of skeletal complications in patients with bone loss, resulting from long-term cancer treatment or osteoporosis, and in patients with malignant bone disease. 6-8 Bisphosphonates are small molecules that dock in hydroxyapatite-binding sites on bone surfaces. When osteoclasts begin to resorb bisphosphonate-impregnated bone, the liberated bisphosphonates bind to farnesyl pyrophosphate synthase inside the osteoclasts, ultimately leading to apoptosis. 8-10 Denosumab is a fully human monoclonal antibody, which has a different mode of action from that of bisphosphonates. It targets and binds to the receptor activator of nuclear factor k-B (RANK) ligand (RANKL); in doing so it prevents the activation of RANK on the surface of osteoclasts and osteoclast precursors. Inhibition of the RANKLÀRANK interaction impedes osteoclast formation, function, and survival, thereby decreasing bone resorption. 11 MRONJ is more prevalent among patients receiving high cumulative doses of bisphosphonates or denosumab than in patients who receive lower doses. 12,13 The first cases Statement of Clinical Relevance Medication-related osteonecrosis of the jaw is a rare, but potentially serious, complication of treatment with bisphosphonates and denosumab. It is important for dentists to be aware of ways to identify and treat patients at risk of this condition.

Patients with solid tumours are at risk of impaired bone health from metastases and cancer therapy-induced bone loss (CTIBL). We review medical management of bone health in patients with solid tumours over the past 30 years, from first-generation bisphosphonates to the receptor activator of nuclear factor κB ligand (RANKL)targeted monoclonal antibody, denosumab. In the 1980s, first-generation bisphosphonates were shown to reduce the incidence of skeletal-related events (SREs) in patients with breast cancer. Subsequently, more potent secondand third-generation bisphosphonates were developed, particularly zoledronic acid (ZA). Head-to-head studies showed that ZA was significantly more effective than pamidronate for reducing SREs in patients with breast and castrate-resistant prostate cancer (CRPC), becoming the standard of care for more than a decade. The RANKL inhibitor denosumab was licensed in 2010, and head-to-head studies and integrated analyses confirmed its superiority to ZA for preventing SREs, particularly in breast cancer and CRPC. Bisphosphonates and denosumab have also been investigated for prevention of CTIBL in patients receiving hormonal therapy for breast and prostate cancer, and denosumab is licensed in this indication. Despite advances in management of bone health, several issues remain, notably the optimal time to initiate therapy, duration of therapy, and dosing frequency, and how to avoid toxicity, particularly with long-term treatment. In summary, introduction of ZA and denosumab has protected patients with bone metastasis from serious bone complications and improved their quality of life. Ongoing research will hopefully guide the optimal use of these agents to help maintain bone health in patients with solid tumours.

Metastatic bone disease in patients with advanced cancer is frequently associated with skeletal complications. These can be debilitating, causing pain, impaired functioning and decreased quality of life, as well as reduced survival. This review considers how the management of metastatic bone pain might be optimised, to limit the considerable burden it can impose on affected patients. Cancer-related pain is notoriously under-reported and under-treated, despite the availability of many therapeutic options. Non-opioid and opioid analgesics can be used; the latter are typically administered with radiotherapy, which forms the current standard of care for patients with metastatic bone pain. Surgery is appropriate for certain complicated cases of metastatic bone disease, and other options such as radiopharmaceuticals may provide additional relief. Treatments collectively referred to as bone-targeted agents (BTAs; bisphosphonates and denosumab) can offer further pain reduction. Initiation of therapy with BTAs is recommended for all patients with metastatic bone disease because these agents delay not only the onset of skeletal-related events but also the onset of bone pain. With evidence also emerging for pain control properties of new anticancer agents, the potential to individualise care for these patients is increased further. Optimisation of care depends on physicians' thorough appreciation of the complementary benefits that might be achieved with the various agents, as well as their limitations. Appropriate anti-tumour treatment combined with early initiation of BTAs and adequate analgesia plays a key role in the holistic approach to cancer pain management and may minimise the debilitating effects of metastatic bone pain.

Bone metastases are common in patients with advanced solid tumors, and many individuals experience debilitating skeletal-related events (SREs; e.g. pathologic fracture, hypercalcemia, radiotherapy or surgery to bone, and spinal cord compression). These events substantially affect disease outcomes, including survival and quality of life, and healthcare systems. Plain radiography is the most widely used imaging modality for the detection of bone metastases; skeletal scintigraphy, computed tomography, positron emission tomography and magnetic resonance imaging offer greater sensitivity but their use in routine practice is restricted by high costs and limited availability. Biomarkers of bone turnover may also have a role in the early detection of bone metastases and can provide valuable prognostic information on disease progression. SREs can be delayed or prevented using agents such as the receptor activator of nuclear factor kappa B ligand (RANKL) inhibitor, denosumab, and bisphosphonates. Painful bone metastases can be treated with radiofrequency ablation, radiotherapy, or radionuclides such as radium-223 dichloride, which has been shown to delay the onset of SREs in men with castration-resistant prostate cancer. Close monitoring of bone health in patients with advanced cancer may lead to early identification of individuals with bone metastases who could benefit from early intervention to prevent SREs. This review examines current guideline recommendations for assessing and monitoring bone health in patients with advanced cancer, use of biomarkers and treatment of patients with bone metastases. The emerging evidence for the potential survival benefit conferred by early intervention with denosumab and bisphosphonates is also discussed, together with best practice recommendations.

PurposeIn 2013, Angelina Jolie disclosed in the New York Times (NYT) that she had undergone risk-reducing bilateral mastectomy (RRBM) after learning that she was a BRCA1 mutation carrier. We examined the rates of BRCA testing and RRBM from 1997 to 2016, and quantified trends before and after the Jolie op-ed.MethodsThis observational study of insurance claims data representative of the commercially-insured US population (Truven MarketScan® database) measured BRCA testing and RRBM rates among females ≥ 18 years. Censoring events were breast cancer or ovarian cancer diagnosis, last follow-up date (September 2016), or death. Interrupted time series analyses were used to quantify trends before and after the op-ed.ResultsAngelina Jolie’s NYT op-ed led to a statistically significant increase in the uptake of genetic testing and in RRBM among women without previous diagnosis of breast or ovarian cancer in the US population, and in women who did not undergo testing for BRCA (P < 0.0001 for both). The rate (slope) of RRBM among women who were previously tested for BRCA (P = 0.70) was unchanged. After excluding women with in-situ tumors, the editorial’s effect became less pronounced, suggesting that high-risk women with in-situ breast cancers were most influenced by Jolie’s announcement.ConclusionThe Angelina Effect—a term coined by Time magazine to describe the rise in internet searches related to breast cancer genetics and counseling—represents a long-lasting impact of celebrity on public health awareness as significant increases in genetic testing and mastectomy rates were observed and sustained in subsequent years.Electronic supplementary materialThe online version of this article (10.1007/s10549-018-4824-9) contains supplementary material, which is available to authorized users.

Drug repurposing offers advantages over traditional drug development in terms of cost, speed and improved patient outcomes. The receptor activator of nuclear factor kappa B (RANK) ligand (RANKL) inhibitor denosumab is approved for the prevention of skeletal-related events in patients with advanced malignancies involving bone, including solid tumours and multiple myeloma. Following improved understanding of the role of RANK/RANKL in cancer biology, denosumab has already been repurposed as a treatment for giant cell tumour of bone. Here, we review the role of RANK/RANKL in tumourigenesis, including effects on tumour initiation, progression and metastasis and consider the impact of RANK/RANKL on tumour immunology and immune evasion. Finally, we look briefly at ongoing trials and future opportunities for therapeutic synergy when combining denosumab with anti-cancer agents such as immune checkpoint inhibitors.

Most men with advanced prostate cancer will develop bone metastases, which have a substantial impact on quality of life. Bone metastases can lead to skeletal-related events (SREs), which place a burden on patients and healthcare systems. For men with castration-resistant prostate cancer (CRPC) and bone metastases, the treatment landscape has evolved rapidly over the past few years. The relatively recent approvals of the hormonal agents abiraterone acetate and enzalutamide, second-line chemotherapy cabazitaxel, and the radiopharmaceutical radium-223 dichloride (radium-223), have provided clinicians with a greater choice of treatments. These compounds have benefits in terms of overall survival based on the results of pivotal phase 3 studies. The bisphosphonate zoledronic acid and the RANK ligand inhibitor denosumab are indicated for the prevention of SREs in men with metastatic CRPC but studies of these compounds have not demonstrated a survival benefit. The important question of the role of bisphosphonates or denosumab in combination with these new agents has thus materialised. Current and emerging evidence from clinical studies of abiraterone acetate, enzalutamide and radium-223, suggest that addition of bisphosphonates or denosumab to these new therapies may provide further clinical benefits for patients with prostate cancer and bone metastases. This evidence may help to shape clinical practice but are based largely on post hoc analyses of clinical trial data. It is therefore apparent that further data are required from both clinical studies and real-world settings to enable physicians to understand the efficacy and safety of combination therapy with the new agents plus bisphosphonates or denosumab.