Treatment-induced bone loss and fractures in cancer patients undergoing hormone ablation therapy: efficacy and safety of denosumab

The Pathogenetic Role of RANK/RANKL/OPG Signaling in Osteoarthritis and Related Targeted Therapies

Background: Osteoarthritis (OA) is the most common degenerative joint disease and affects millions of people worldwide, particularly the elderly population. The pathophysiology of OA is complex and involves multiple factors. Methods: Several studies have emphasized the crucial role of inflammation in this process. The receptor activator of NF-κB ligand (RANKL), the receptor activator of NF-κB (RANK), and osteoprotegerin (OPG) trigger a signaling cascade that leads to the excessive production of RANKL in the serum. Conclusions: The aim of this narrative review is (i) to assess the role of the RANK/RANKL/OPG signaling pathway in the context of OA progression, focusing especially on the physiopathology and on all the mechanisms leading to the activation of the inflammatory cascade, and (ii) to evaluate all the potential therapeutic strategies currently available that restore balance to bone formation and resorption, reducing structural abnormalities and relieving pain in patients with OA.

Clinical practice guidelines for full-cycle standardized management of bone health in breast cancer patients

Bone health management for breast cancer spans the entire cycle of patient care, including the prevention and treatment of bone loss caused by early breast cancer treatment, the adjuvant application of bone-modifying agents to improve prognosis, and the diagnosis and treatment of advanced bone metastases. Making good bone health management means formulating appropriate treatment strategies and dealing with adverse drug reactions, and will help to improve patients' quality of life and survival rates. The Breast Cancer Expert Committee of the National Cancer Center for Quality Control organized relevant experts to conduct an in-depth discussion on the full-cycle management of breast cancer bone health based on evidence-based medicine, and put forward reasonable suggestions to guide clinicians to better deal with health issues in bone health clinics.

Proceedings of the 2022 Santa Fe Bone Symposium: Current Concepts in the Care of Patients with Osteoporosis and Metabolic Bone Diseases

The 22^nd Annual Santa Fe Bone Symposium (SFBS) was a hybrid meeting held August 5-6, 2022, with in-person and virtual attendees. Altogether, over 400 individuals registered, a majority of whom attended in-person, representing many states in the USA plus 7 other countries. The SFBS included 10 plenary presentations, 2 faculty panel discussions, satellite symposia, Bone Health & Osteoporosis Foundation Fracture Liaison Service Boot Camp, and a Project ECHO workshop, with lively interactive discussions for all events. Topics of interest included fracture prevention at different stages of life; how to treat and when to change therapy; skeletal health in cancer patients; advanced imaging to assess bone strength; the state of healthcare in the USA; osteosarcopenia; vitamin D update; perioperative bone health care; new guidelines for managing primary hyperparathyroidism; new concepts on bone modeling and remodeling; and an overview on the care of rare bone diseases, including hypophosphatasia, X-linked hypophosphatemia, tumor induced osteomalacia, osteogenesis imperfecta, fibrodysplasia ossificans progressiva, and osteopetrosis. The SFBS was preceded by the Santa Fe Fellows Workshop on Osteoporosis and Metabolic Bone Diseases, a collaboration of the Endocrine Fellows Foundation and the Osteoporosis Foundation of New Mexico. From the Workshop, 4 participating fellows were selected to give oral presentations at the bone symposium. These proceedings represent the clinical highlights of 2022 SFBS presentations and the discussions that followed, all with the aim of optimizing skeletal health and minimizing the consequences of fragile bones.

Cancer Treatment-Induced Bone Loss: Role of Denosumab in Non-Metastatic Breast Cancer

Chemotherapeutic agents, endocrine therapy and radiotherapy used in the management of breast cancer are known to cause decreased bone mineral density, and thus, increased incidence of fractures. A majority (~60%) of the breast cancer patients in India are either estrogen (ER) or progesterone hormone receptor (PR) positive. Adjuvant treatment with aromatase inhibitors (AIs) is the treatment mainstay for hormone-sensitive disease in postmenopausal (PM) women, with reduced bone mineral density (BMD), which results in increased fracture rates. Zoledronic acid, alendronate, risedronate and denosumab have been the agents of choice for managing bone loss. Denosumab 60 mg is approved for gaining bone mass in women with breast cancer who are at high risk for fracture following adjuvant AI treatment. The phase III HALT-BC data indicate an improvement in BMD with denosumab and a 50% reduction in clinical fractures, with significant improvements seen at the lumbar spine, distal third of the radius, and total hip. Denosumab has several advantages over other bone modifying agents such as subcutaneous self-administration by the patient themselves, no requirement of hospitalization, no dose modifications in renal impairment, and low incidence of acute phase anaphylactic reactions. We review the available evidence of denosumab for managing bone loss in non-metastatic breast cancer patients.

RANKL Blockade Reduces Cachexia and Bone Loss Induced by Non-Metastatic Ovarian Cancer in Mice

Tumor- and bone-derived soluble factors have been proposed to participate in the alterations of skeletal muscle size and function in cachexia. We previously showed that mice bearing ovarian cancer (OvCa) exhibit cachexia associated with marked bone loss, whereas bone-targeting agents, such as bisphosphonates, are able to preserve muscle mass in animals exposed to anticancer drugs. De-identified CT images and plasma samples from female patients affected with OvCa were used for body composition assessment and quantification of circulating cross-linked C-telopeptide type I (CTX-I) and receptor activator of NF-kB ligand (RANKL), respectively. Female mice bearing ES-2 tumors were used to characterize cancer- and RANKL-associated effects on muscle and bone. Murine C2C12 and human HSMM myotube cultures were used to determine the OvCa- and RANKL-dependent effects on myofiber size. To the extent of isolating new regulators of bone and muscle in cachexia, here we demonstrate that subjects affected with OvCa display evidence of cachexia and increased bone turnover. Similarly, mice carrying OvCa present high RANKL levels. By using in vitro and in vivo experimental models, we found that elevated circulating RANKL is sufficient to cause skeletal muscle atrophy and bone resorption, whereas bone preservation by means of antiresorptive and anti-RANKL treatments concurrently benefit muscle mass and function in cancer cachexia. Altogether, our data contribute to identifying RANKL as a novel therapeutic target for the treatment of musculoskeletal complications associated with RANKL-expressing non-metastatic cancers. © 2021 American Society for Bone and Mineral Research (ASBMR).

Efficacy of Antiresorptive Drugs on Bone Mineral Density in Post-Menopausal Women With Early Breast Cancer Receiving Adjuvant Aromatase Inhibitors: A Systematic Review of Randomized Controlled Trials

Background

Cancer treatment-induced bone loss (CTIBL) is a frequent complication of breast cancer therapies affecting both disability and health-related quality of life (HRQoL). To date, there is still a lack of consensus about the most effective approach that would improve bone health and HRQoL. Therefore, the aim of this systematic review of randomized controlled trials (RCTs) was to summarize the evidence on the effects of antiresorptive drugs on CTIBL in patients with early breast cancer.

Methods

PubMed, Scopus, and Web of Science databases were systematically searched up to April 30, 2021 to identify RCTs satisfying the following PICO model: P) Participants: postmenopausal women with early breast cancer receiving adjuvant aromatase inhibitors (AI), age >18 years; I) Intervention: antiresorptive drugs (i.e. bisphosphonates and/or denosumab); C) Comparator: any comparator; O) Outcome: bone mineral density (BMD) modifications. Moreover, a quality assessment was performed according to the Jadad scale.

Results

Out of the initial 2415 records, 21 papers (15 studies) were included in the data synthesis. According to the Jadad scale, 6 studies obtained a score of 5, 1 study obtained a score of 4, 13 studies obtained a score of 3, and 1 study with score 1. Although both bisphosphonates and denosumab showed to increase BMD, only denosumab showed significant advantages on fractures.

Conclusions

Bone health management in patients with early breast cancer receiving adjuvant AIs remains challenging, and the optimal therapeutic approach is not standardized. Further studies are needed to investigate CTIBL, focusing on both the need for antiresorptive drugs and their duration based on individual patients’ characteristics.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero, identifier CRD42021267107.

Toxicity of extended adjuvant endocrine with aromatase inhibitors in patients with postmenopausal breast cancer: A Systemtic review and Meta-analysis

BACKGROUND

Extended endocrine therapy (EET) with aromatase inhibitors (AIs) therapy can further reduce the risk of recurrence in breast cancer patients. But the conclusion that whether EET with AIs increases the risk of some side effects compared with nonextended endocrine therapy (NEET) is still controversial and not exhaustive.

METHODS

We searched for Randomized controlled trials (RCT) trials published in EMBASE and PubMed between March 2008 and December 2019. Studies comparing the side effects of adjuvant EET with those of NEET were included. The objective was to determine whether EET with AIs increases the risk of side effects compared with NEET.

RESULTS

Overall, 11 trials comprising 24,187 participants were identified. EET with AIs increased the risk of cardiotoxicity [odds ratio (OR) 1.19, 95 % confidence interval (CI) 1.04-1.36; P < 0.05; 438 vs 423], bone pain (OR 1.18, 95 % CI 1.02-1.36; P < 0.05; 446 vs 404), osteoporosis (OR 1.53, 95 % CI 1.35-1.72; P < 0.05; 866 vs 641), fractures (OR 1.33, 95 % CI 1.18-1.50; P < 0.05; 596 vs 438), arthralgia (OR 1.27, 95 % CI 1.19-1.36; P < 0.05; 2404 vs 2060), myalgia (OR 1.29, 95 % CI 1.16-1.43; P < 0.05; 960 vs 776), and hot flashes (OR 1.40, 95 % CI 1.15-1.69; P < 0.05; 2418 vs 2174) and was associated with opposite risk of vaginal bleeding (OR 0.74, 95 % CI 0.59-0.92; P < 0.05; 148 vs 197). However, the extended therapy did not increase the risk of hypertension (OR 1.03, 95 % CI 0.80-1.33; P = 0.80; 364 vs 353), hypercholesterolemia (OR 1.03, 95 % CI 0.91-1.16; P = 0.62; 643 vs 627), vaginal dryness (OR 1.19, 95 % CI 1.00-1.42; P = 0.05; 294 vs 257), fatigue (OR 1.20, 95 % CI 0.96-1.50; P = 0.12; 1501 vs 1462), dizziness (OR 1.04, 95 % CI 0.92-1.17; P = 0.55; 614 vs 595), headaches (OR 1.06, 95 % CI 0.95-1.18; P = 0.30; 885 vs 848), constipation (OR 0.91, 95 % CI 0.79-1.04; P = 0.15; 480 vs 522), nausea (OR 1.83, 95 % CI 0.49-6.83; P =0.37; 340 vs 325), and dyspnea (OR 0.96, 95 % CI 0.82-1.13; P = 0.64; 340 vs 351). The risk of grade ≥ 3 hot flashes increased following extended endocrine therapy (OR 2.01, 95 % CI 1.23-3.29; P < 0.05; 47 vs 23). We observed no evidence for a difference in the risk of grade ≥3 fatigue, arthralgia, myalgia, bone pain, osteoporosis, fractures, hypertension, and headache between both endocrine therapies. Secondary outcomes shows that after receive EET with AIs, patients can benefit from the control of the local recurrence, distant recurrence, contralateral breast cancer, and second cancers.

CONCLUSIONS

Compared with NEET, EET with AIs significantly increased the risk of cardiotoxicity, bone pain, osteoporosis, fractures, hot flashes, arthralgia, myalgia, and grade ≥3 hot flashes, and EET with AIs can reduced the risks of local recurrence, distant recurrence, contralateral breast cancer, and second cancers. These findings offer an important guide for clinicians and patients.

Bilateral Atypical Femur Fractures Complicated by Carbon Fiber Cephalomedullary Nail Fracture: A Case Report

CASE

A 69-year-old woman with a history of breast cancer, on long-term antiresorptive medications, was treated with carbon fiber cephalomedullary nails for bilateral atypical femur fractures. Her thigh pain was presumed to be from metastatic lesions and was treated with radiation without standard imaging. The index procedure was complicated by a left nail fracture. The patient underwent exchange cephalomedullary nail fixation with plate augmentation. At 1 year, the patient was asymptomatic with radiographs demonstrating healing.

CONCLUSION

This case highlights the importance of appropriate imaging in all patients with thigh pain on antiresorptive therapy and features an uncommon complication of carbon fiber cephalomedullary nail fixation.

Estrogen activates pyruvate kinase M2 and increases the growth of TSC2-deficient cells

Lymphangioleiomyomatosis (LAM) is a devastating lung disease caused by inactivating gene mutations in either TSC1 or TSC2 that result in hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1). As LAM occurs predominantly in women during their reproductive age and is exacerbated by pregnancy, the female hormonal environment, and in particular estrogen, is implicated in LAM pathogenesis and progression. However, detailed underlying molecular mechanisms are not well understood. In this study, utilizing human pulmonary LAM specimens and cell culture models of TSC2-deficient LAM patient-derived and rat uterine leiomyoma-derived cells, we tested the hypothesis that estrogen promotes the growth of mTORC1-hyperactive cells through pyruvate kinase M2 (PKM2). Estrogen increased the phosphorylation of PKM2 at Ser37 and induced the nuclear translocation of phospho-PKM2. The estrogen receptor antagonist Faslodex reversed these effects. Restoration of TSC2 inhibited the phosphorylation of PKM2 in an mTORC1 inhibitor-insensitive manner. Finally, accumulation of phosphorylated PKM2 was evident in pulmonary nodule from LAM patients. Together, our data suggest that female predominance of LAM might be at least in part attributed to estrogen stimulation of PKM2-mediated cellular metabolic alterations. Targeting metabolic regulators of PKM2 might have therapeutic benefits for women with LAM and other female-specific neoplasms.

Clinical and translational pharmacology of drugs for the prevention and treatment of bone metastases and cancer-induced bone loss

Bone disease is a frequent event in cancer patients, both due to cancer spread to bone and to cancer therapies. Bone is the organ most frequently affected by metastatic disease when considering the two most frequent cancers in the Western world (breast and prostate cancers). Bone metastases can have a substantial detrimental effect on patients' quality of life, as well as significant morbidity due to complications collectively known as skeletal-related events (SREs), which include hypercalcaemia, pathological fractures, spinal cord compression, and need of radiotherapy or surgery to the bone. These have been successfully mitigated with the development of bone-targeted agents (BTAs; bisphosphonates and denosumab), focused on inhibiting osteoclast activity. The potential direct antitumour effect of bisphosphonates, as well as the impact of osteoclast inhibition with subsequent decrease in bone metabolism, have also propelled investigation on the role of BTAs in preventing cancer relapse in bone. In this review, the authors aimed to discuss the role of BTAs in the treatment and prevention of bone metastases, as well as their potential value in preventing cancer treatment-induced bone loss (CTIBL). The review will focus on breast and prostate cancers, with the aim of providing the most relevant clinical data emerging from bench to bedside translational research in the field of cancer-induced bone disease.

The skeletal impact of cancer therapies

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

Guidelines for the management of osteoporosis and fragility fractures

The purpose of this document, a result of the harmonisation and revision of Guidelines published separately by the SIMFER, SIOMMMS/SIR, and SIOT associations, is to provide practical indications based on specific levels of evidence and various grades of recommendations, drawn from available literature, for the management of osteoporosis and for the diagnosis, prevention, and treatment of fragility fractures. These indications were discussed and formally approved by the delegates of the Italian Scientific Associations involved in the project (SIE, SIGG, SIMFER, SIMG, SIMI, SIOMMMS, SIR, and SIOT).

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.

The prevention of fragility fractures in patients with non-metastatic prostate cancer: a position statement by the international osteoporosis foundation

Androgen deprivation therapy is commonly employed for the treatment of non-metastatic prostate cancer as primary or adjuvant treatment. The skeleton is greatly compromised in men with prostate cancer during androgen deprivation therapy because of the lack of androgens and estrogens, which are trophic factors for bone. Men receiving androgen deprivation therapy sustain variable degrees of bone loss with an increased risk of fragility fractures. Several bone antiresorptive agents have been tested in randomized controlled trials in these patients. Oral bisphosphonates, such as alendronate and risedronate, and intravenous bisphosphonates, such as pamidronate and zoledronic acid, have been shown to increase bone density and decrease the risk of fractures in men receiving androgen deprivation therapy. Denosumab, a fully monoclonal antibody that inhibits osteoclastic-mediated bone resorption, is also effective in increasing bone mineral density and reducing fracture rates in these patients. The assessment of fracture risk, T-score and/or the evaluation of prevalent fragility fractures are mandatory for the selection of patients who will benefit from antiresorptive therapy. In the future, new agents modulating bone turnover and skeletal muscle metabolism will be available for testing in these subjects.

Effects of raloxifene against letrozole-induced bone loss in chemically-induced model of menopause in mice

INTRODUCTION

The deleterious effects of letrozole, an aromatase inhibitor, used in the adjuvant treatment of breast cancer in postmenopausal women, on bone are well-documented and represent a major drawback to its clinical use. Raloxifene, a selective estrogen receptor modulator and a clinically approved anti-osteoporotic drug, has been recently demonstrated to be efficacious in women with breast cancer. The present study evaluated the effects of preventive and curative treatment with raloxifene on letrozole-induced alterations of bone microarchitecture and turnover markers in a chemically-induced menopause model in mice.

METHOD

Swiss strain albino female mice were made menopausal by inducing ovotoxicity using vinyl cyclohexene di epoxide (VCD, 160 mg/kg for 15 days followed by 30 days drug-free period) confirmed by ovarian histology and serum estradiol levels. Effects on femoral and lumbar bones were evaluated by micro CT determination of bone volume, trabecular number, separation, thickness, connective density and trabecular pattern factor and bone turnover markers including ALP, TRAP5b, hydroxyproline and RANKL. In addition to these, markers of Wnt signaling (sclerostin and dickkopf-1) were also evaluated. To rule out the involvement of pharmacokinetic interaction, plasma levels of letrozole and raloxifene were measured following drugs alone and in combination.

RESULTS

Though bone loss was observed in VCD treated mice (as indicated by micro CT measurements), it was further enhanced with letrozole administration (1 mg/kg) for one month particularly in epiphysis of femoral bones. Raloxifene (15 mg/kg), whether administered concurrently or post-letrozole was able to revert the structural alterations and changes in turnover markers caused by letrozole to varying degrees (p < 0.01 or p < 0.001). Further, estrogen deficiency following letrozole treatment in ovotoxic mice was associated with significant increase in sclerostin and dickkopf-1 in both lumbar and femur bones (p < 0.001) which was attenuated with preventive and curative treatment with raloxifene (p < 0.05). The plasma levels of letrozole remained unaffected by raloxifene administration and vice versa.

CONCLUSIONS

Our study indicates the potential of raloxifene in preventing and attenuating letrozole-induced bone loss. Further, these effects were found to be independent of a pharmacokinetic interaction between the two drugs.

Assessment of off-label use of denosumab 60 mg injection during the early postmarketing period using health insurance claims data

Off-label use of denosumab 60 milligram (mg) injection was assessed within an administrative claims database. The completeness of claims to assess off-label use was investigated with medical record review. Potential denosumab 60 mg off-label use was observed based on claims, but many had evidence of on-label indications based on medical record review.

INTRODUCTION

Denosumab 60 mg injection is approved in the USA to treat patients at high fracture risk due to postmenopausal osteoporosis, male osteoporosis, and hormone therapy for the treatment of prostate and breast cancers. Its RANK ligand-inhibiting effect makes it a candidate for the off-label treatment of other conditions mediated by the rate of bone resorption by osteoclasts. To better understand its utilization patterns, we assessed off-label use of denosumab 60 mg within an administrative claims database.

METHODS

Definite, probable, and possible denosumab 60 mg users were identified during the early postmarketing period within a claims database of a US healthcare insurer. Medical record review confirmed a sample of these users. Off-label use among definite and probable users and all chart-confirmed users was classified using claims-derived age, dose interval, and diagnosis and treatment received relative to the administration date. Among chart-confirmed users classified as off-label, patient characteristics related to treatment indication were abstracted from medical records to investigate the completeness of claims to study off-label medication use.

RESULTS

Off-label use was identified based on claims in approximately 25 % of definite and probable denosumab 60 mg users and 35 % of chart-confirmed users. Medical record review identified evidence of on-label indications in 81 % of chart-confirmed users classified as off-label in claims.

CONCLUSIONS

Many of the off-label denosumab 60 mg users had diagnoses or treatment consistent with on-label indications based on medical record review, suggesting these are under-recorded in claims data. It is warranted to be cautious when using administrative databases to assess off-label medication use.

Bone health in adults treated with endocrine therapy for early breast or prostate cancer

Bone is a hormonally responsive organ. Sex hormones and calcium regulating hormones, including parathyroid hormone, 1-25 dihydroxy vitamin D, and calcitonin, have effects on bone resorption and bone deposition. These hormones affect both bone quality and bone quantity. The sex hormone estrogen inhibits bone resorption, and estrogen therapy has been developed to prevent and treat osteoporosis. Androgens are an important source of estrogen through the action of the enzyme aromatase and may themselves stimulate bone formation. Hence, the sex steroids play a role in bone metabolism. Breast cancer and prostate cancer are frequently hormonally responsive and may be treated with antiestrogens or antiandrogens respectfully. In addition, chemotherapy and supportive medications may alter the patient's endocrine system. In general, the suppression of sex hormones has a predictable affect on bone health, as seen by loss of bone mineral density and increased risk of fragility fractures. The bone toxicity of cancer-directed endocrine therapy can be mitigated through screening, counseling on optimization of calcium and vitamin D intake, exercise, and other lifestyle/behavioral actions, as well as the use of medications when the fracture risk is high. Maintaining bone health in patients who are treated with endocrine therapy for breast and prostate cancer is the focus of this review.

The best of both worlds - managing the cancer, saving the bone

In the context of breast cancer, the importance of the skeleton in the regulation of primary tumour development and as a site for subsequent metastasis is well characterized. Our understanding of the contributions made by the host bone and bone marrow cells increasingly demonstrates the extent of the interaction between tumour cells and normal host cells. As a result, the need to develop and utilize therapies that can impede the growth and/or function of tumour cells while sparing normal host bone and bone marrow cells is immense and expanding. The need for these new treatments is, however, superimposed on the orthopaedic management of patients' quality of life, where pain control and continued locomotion are paramount. Indeed, the majority of the anticancer therapies used to date often result in direct or indirect damage to bone. Thus, although the bone microenvironment regulates tumour cell growth in bone, cells within the bone marrow niche also mediate many of the orthopaedic consequences of tumour progression as well as resistance to the antitumour effects of existing therapies. In this Review, we highlight the effects of existing cancer treatments on bone and the bone marrow microenvironment as well as the mechanisms mediating these effects and the current utility of modern orthopaedic interventions.

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.

Testosterone and estradiol treatments differently affect pituitary-thyroid axis and liver deiodinase 1 activity in orchidectomized middle-aged rats

We previously reported that orchidectomy (Orx) of middle-aged rats (15-16-month-old; MA) slightly affected pituitary-thyroid axis, but decreased liver deiodinase (Dio) type 1 and pituitary Dio2 enzyme activities. At present, we examined the effects of subsequent testosterone-propionate treatment (5mg/kg; Orx+T), and compared the effects of testosterone with the effects of estradiol-dipropionate (0.06mg/kg; Orx+E) treatment. Hormones were subcutaneously administered, daily, for three weeks, while Orx and sham-operated (SO) controls received only the vehicle. The applied dose of T did not alter serum TSH, T4 and T3 concentrations in Orx- MA, though it increased TSH when administrated to Orx young adults (2.5-month-old; Orx-YA). However, pituitaries of Orx-MA+T rats had higher relative intensity of immunofluorescence (RIF) for TSHβ; in their thyroids we found increased volume and height of follicular epithelium, decreased volume of the colloid and higher RIF for T4-bound to thyroglobulin (Tg-T4). Liver Dio1 activity was increased. E-treatment did not affect serum hormone levels, pituitary RIF for TSHβ, or liver Dio1 activity in Orx-MA rats. Thyroids had decreased relative volume and height of follicular epithelium, increased relative volume of the colloid, decreased volume of sodium-iodide symporter-immunopositive epithelium and lower RIF for Tg-T4. Detected changes were statistically significant. In conclusion, androgenization enhanced pituitary TSHβ RIF, thyroid activation and liver Dio1 enzyme activity in Orx-MA, without elevating serum TSH as in Orx-YA rats. Estrogenization induced pituitary enlargement with no effect on pituitary TSHβ RIF, serum TSH or liver Dio1 activity. E also induced alterations in thyroid histology that indicate mild suppression of its functioning, and contributed to thyroid blood vessel enlargement in Orx-MA rats.

Antiresorptive therapy in the management of cancer treatment-induced bone loss

Cancer treatment-induced bone loss treatment has an important role to prevent bone loss-related events like fracture, significant morbidity, mortality, disfigurement and loss of self-esteem, and health-care expenditure. Numerous factors, including treatment regimens and bone metastasis, increase the risk of osteoporosis or local bone destruction in most breast and prostate cancer patients. Cytotoxic chemotherapies, radiation, and hormonal therapies can lead to premature menopause and decrease bone mineral density. Over 60 % of breast cancer patients within 1 year of beginning postoperative adjuvant chemotherapy experience ovarian failure. Also, ovarian ablation and aromatase inhibitors used to treat breast cancer and orchiectomy and androgen deprivation therapy (ADT; to treat prostate cancer) cause substantial bone loss. In this article, we will focus mainly on antiresorptive therapy in the management of cancer treatment-induced bone loss (CTIBL). An understanding of CTIBL is critical for determining how to assess the risk and identify which patients may benefit from preventive therapy.

Development and evaluation of an algorithm to identify users of Prolia(®) during the early postmarketing period using health insurance claims data

PURPOSE

The goal of this study is to develop and validate an algorithm to identify Prolia(®) users within a health insurance claims database.

METHODS

Patients with a denosumab-specific or nonspecific administration claim during the early period of Prolia availability in the USA (June 1, 2010 to March 31, 2012) were classified as definite, probable, possible, and nonusers of Prolia using an algorithm consisting of nine different components based on claims patterns consistent with Prolia use. Medical record review confirmed a sample of definite, probable, and possible users and the positive predictive value (PPV) was estimated.

RESULTS

The PPV of the claims-based algorithm components varied (17.8-95.8%). Requiring claims for a bone or cartilage disorder or osteoporotic fracture after excluding claims for cancer prior to a denosumab-specific administration code gave the highest PPV (95.8%), followed by requiring a Prolia National Drug Code on the same claim as a denosumab-specific or nonspecific administration code (88.2%). Among the 87 confirmed Prolia users, osteoporosis diagnoses were seen more frequently in the medical record than in claims (83% vs 62%).

CONCLUSIONS

Prolia users are most accurately identified with administration code claims in conjunction with claims for Prolia National Drug Code and bone disorder treatment and diagnosis codes. Osteoporosis diagnoses may be under-recorded in claims data. The algorithm may require reassessment as uptake for more recently approved indications increases.

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.

Infusion therapy and implantables for the urologist

The specialty of urology has historically adapted to the changing health care environment. Urologists have been quick to adopt new technology, new therapeutics, and devices to render state-of-the-art patient care with improved clinical outcomes. The busy urology practice is now in the position to deliver many novel and unique therapies across multiple disease states. As a result, clinicians can provide state-of-the-art care in a clinic setting and potentially reduce the overall costs of health care delivery. This article reviews some of these potential new opportunities available to the practicing urologist.