Effects of Exemestane and Tamoxifen treatment on bone texture analysis assessed by TBS in comparison with bone mineral density assessed by DXA in women with breast cancer

Effect of bisphosphonate and denosumab treatment on TBS in Japanese breast cancer patients with AIBL

INTRODUCTION

Bisphosphonates and denosumab increase bone mineral density (BMD) for osteoporosis treatment in patients with aromatase inhibitor-associated bone loss (AIBL). This study aimed to directly compare bisphosphonates with denosumab in treating patients with AIBL and to determine the effect of denosumab on the trabecular bone score (TBS).

MATERIALS AND METHODS

Thirty-nine patients with AIBL receiving osteoporosis treatment (21 in the bisphosphonates group and 18 in the denosumab group) were retrospectively evaluated for changes in lumbar spine and femoral BMD, lumbar spine bone quality (assessed by TBS), and blood bone metabolic markers. The Mann-Whitney and Wilcoxon tests were used for statistical evaluation.

RESULTS

After 24 months of treatment, the lumbar spine BMD change rate was 5.82 ± 1.10% with bisphosphonates and 10.49 ± 1.20% with denosumab, with the change rate of denosumab significantly increasing over that of bisphosphonates. The change rate in femoral BMD was 2.69 ± 1.16% with bisphosphonates and 2.95 ± 1.26% with denosumab, with no significant difference between the two groups. The rate of decrease in tartrate-resistant acid phosphatase isoform 5b was significantly higher in the denosumab group. The change rate in TBS at 24 months of treatment was 0.53 ± 1.26% in the bisphosphonates group and 1.08 ± 1.33% in the denosumab group, with no significant difference between the two groups. After 24 months, TBS remained stable.

CONCLUSION

Both bisphosphonates and denosumab may increase BMD, improve bone metabolism, and inhibit bone quality loss in patients with AIBL.

Bone-modifying agents for reducing bone loss in women with early and locally advanced breast cancer: a network meta-analysis

BACKGROUND

Bisphosphonates and receptor activator of nuclear factor-kappa B ligand (RANKL)-inhibitors are amongst the bone-modifying agents used as supportive treatment in women with breast cancer who do not have bone metastases. These agents aim to reduce bone loss and the risk of fractures. Bisphosphonates have demonstrated survival benefits, particularly in postmenopausal women.

OBJECTIVES

To assess and compare the effects of different bone-modifying agents as supportive treatment to reduce bone mineral density loss and osteoporotic fractures in women with breast cancer without bone metastases and generate a ranking of treatment options using network meta-analyses (NMAs).

SEARCH METHODS

We identified studies by electronically searching CENTRAL, MEDLINE and Embase until January 2023. We searched various trial registries and screened abstracts of conference proceedings and reference lists of identified trials.

SELECTION CRITERIA

We included randomised controlled trials comparing different bisphosphonates and RANKL-inihibitors with each other or against no further treatment or placebo for women with breast cancer without bone metastases.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias of included studies and certainty of evidence using GRADE. Outcomes were bone mineral density, quality of life, overall fractures, overall survival and adverse events. We conducted NMAs and generated treatment rankings.

MAIN RESULTS

Forty-seven trials (35,163 participants) fulfilled our inclusion criteria; 34 trials (33,793 participants) could be considered in the NMA (8 different treatment options). Bone mineral density We estimated that the bone mineral density of participants with no treatment/placebo measured as total T-score was -1.34. Evidence from the NMA (9 trials; 1166 participants) suggests that treatment with ibandronate (T-score -0.77; MD 0.57, 95% CI -0.05 to 1.19) may slightly increase bone mineral density (low certainty) and treatment with zoledronic acid (T-score -0.45; MD 0.89, 95% CI 0.62 to 1.16) probably slightly increases bone mineral density compared to no treatment/placebo (moderate certainty). Risedronate (T-score -1.08; MD 0.26, 95% CI -0.32 to 0.84) may result in little to no difference compared to no treatment/placebo (low certainty). We are uncertain whether alendronate (T-score 2.36; MD 3.70, 95% CI -2.01 to 9.41) increases bone mineral density compared to no treatment/placebo (very low certainty). Quality of life No quantitative analyses could be performed for quality of life, as only three studies reported this outcome. All three studies showed only minimal differences between the respective interventions examined. Overall fracture rate We estimated that 70 of 1000 participants with no treatment/placebo had fractures. Evidence from the NMA (16 trials; 19,492 participants) indicates that treatment with clodronate or ibandronate (42 of 1000; RR 0.60, 95% CI 0.39 to 0.92; 40 of 1000; RR 0.57, 95% CI 0.38 to 0.86, respectively) decreases the number of fractures compared to no treatment/placebo (high certainty). Denosumab or zoledronic acid (51 of 1000; RR 0.73, 95% CI 0.52 to 1.01; 55 of 1000; RR 0.79, 95% CI 0.56 to 1.11, respectively) probably slightly decreases the number of fractures; and risedronate (39 of 1000; RR 0.56, 95% CI 0.15 to 2.16) probably decreases the number of fractures compared to no treatment/placebo (moderate certainty). Pamidronate (106 of 1000; RR 1.52, 95% CI 0.75 to 3.06) probably increases the number of fractures compared to no treatment/placebo (moderate certainty). Overall survival We estimated that 920 of 1000 participants with no treatment/placebo survived overall. Evidence from the NMA (17 trials; 30,991 participants) suggests that clodronate (924 of 1000; HR 0.95, 95% CI 0.77 to 1.17), denosumab (927 of 1000; HR 0.91, 95% CI 0.69 to 1.21), ibandronate (915 of 1000; HR 1.06, 95% CI 0.83 to 1.34) and zoledronic acid (925 of 1000; HR 0.93, 95% CI 0.76 to 1.14) may result in little to no difference regarding overall survival compared to no treatment/placebo (low certainty). Additionally, we are uncertain whether pamidronate (905 of 1000; HR 1.20, 95% CI 0.81 to 1.78) decreases overall survival compared to no treatment/placebo (very low certainty). Osteonecrosis of the jaw We estimated that 1 of 1000 participants with no treatment/placebo developed osteonecrosis of the jaw. Evidence from the NMA (12 trials; 23,527 participants) suggests that denosumab (25 of 1000; RR 24.70, 95% CI 9.56 to 63.83), ibandronate (6 of 1000; RR 5.77, 95% CI 2.04 to 16.35) and zoledronic acid (9 of 1000; RR 9.41, 95% CI 3.54 to 24.99) probably increases the occurrence of osteonecrosis of the jaw compared to no treatment/placebo (moderate certainty). Additionally, clodronate (3 of 1000; RR 2.65, 95% CI 0.83 to 8.50) may increase the occurrence of osteonecrosis of the jaw compared to no treatment/placebo (low certainty). Renal impairment We estimated that 14 of 1000 participants with no treatment/placebo developed renal impairment. Evidence from the NMA (12 trials; 22,469 participants) suggests that ibandronate (28 of 1000; RR 1.98, 95% CI 1.01 to 3.88) probably increases the occurrence of renal impairment compared to no treatment/placebo (moderate certainty). Zoledronic acid (21 of 1000; RR 1.49, 95% CI 0.87 to 2.58) probably increases the occurrence of renal impairment while clodronate (12 of 1000; RR 0.88, 95% CI 0.55 to 1.39) and denosumab (11 of 1000; RR 0.80, 95% CI 0.54 to 1.19) probably results in little to no difference regarding the occurrence of renal impairment compared to no treatment/placebo (moderate certainty).

AUTHORS' CONCLUSIONS

When considering bone-modifying agents for managing bone loss in women with early or locally advanced breast cancer, one has to balance between efficacy and safety. Our findings suggest that bisphosphonates (excluding alendronate and pamidronate) or denosumab compared to no treatment or placebo likely results in increased bone mineral density and reduced fracture rates. Our survival analysis that included pre and postmenopausal women showed little to no difference regarding overall survival. These treatments may lead to more adverse events. Therefore, forming an overall judgement of the best ranked bone-modifying agent is challenging. More head-to-head comparisons, especially comparing denosumab with any bisphosphonate, are needed to address gaps and validate the findings of this review.

Guidelines for fracture risk assessment and management of osteoporosis in postmenopausal women and men above the age of 50 in Qatar

We present comprehensive guidelines for osteoporosis management in Qatar. Formulated by the Qatar Osteoporosis Association, the guidelines recommend the age-dependent Qatar fracture risk assessment tool for screening, emphasizing risk-based treatment strategies and discouraging routine dual-energy X-ray scans. They offer a vital resource for physicians managing osteoporosis and fragility fractures nationwide.

PURPOSE

Osteoporosis and related fragility fractures are a growing public health issue with an impact on individuals and the healthcare system. We aimed to present guidelines providing unified guidance to all healthcare professionals in Qatar regarding the management of osteoporosis.

METHODS

The Qatar Osteoporosis Association formulated guidelines for the diagnosis and management of osteoporosis in postmenopausal women and men above the age of 50. A panel of six local rheumatologists who are experts in the field of osteoporosis met together and conducted an extensive review of published articles and local and international guidelines to formulate guidance for the screening and management of postmenopausal women and men older than 50 years in Qatar.

RESULTS

The guidelines emphasize the use of the age-dependent hybrid model of the Qatar fracture risk assessment tool for screening osteoporosis and risk categorization. The guidelines include screening, risk stratification, investigations, treatment, and monitoring of patients with osteoporosis. The use of a dual-energy X-ray absorptiometry scan without any risk factors is discouraged. Treatment options are recommended based on risk stratification.

CONCLUSION

Guidance is provided to all physicians across the country who are involved in the care of patients with osteoporosis and fragility fractures.

Fracture risk and assessment in adults with cancer

Individuals with cancer face unique risk factors for osteoporosis and fractures. Clinicians must consider the additive effects of cancer-specific factors, including treatment-induced bone loss, and premorbid fracture risk, utilizing FRAX score and bone mineral densitometry when available. Pharmacologic therapy should be offered as per cancer-specific guidelines, when available, or local general osteoporosis guidelines informed by clinical judgment and patient preferences. Our objective was to review and summarize the epidemiologic burden of osteoporotic fracture risk and fracture risk assessment in adults with cancer, and recommended treatment thresholds for cancer treatment-induced bone loss, with specific focus on breast, prostate, thyroid, gynecological, multiple myeloma, and hematopoietic stem cell transplant. This narrative review was informed by PubMed searches to July 25, 2022, that combined terms for cancer, stem cell transplantation, fracture, bone mineral density (BMD), trabecular bone score, FRAX, Garvan nomogram or fracture risk calculator, QFracture, prediction, and risk factors. The literature informs that cancer can impact bone health in numerous ways, leading to both systemic and localized decreases in BMD. Many cancer treatments can have detrimental effects on bone health. In particular, hormone deprivation therapies for hormone-responsive cancers such as breast cancer and prostate cancer, and hematopoietic stem cell transplant for hematologic malignancies, adversely affect bone turnover, resulting in osteoporosis and fractures. Surgical treatments such as hysterectomy with bilateral salpingo-oophorectomy for gynecological cancers can also lead to deleterious effects on bone health. Radiation therapy is well documented to cause localized bone loss and fractures. Few studies have validated the use of fracture risk prediction tools in the cancer population. Guidelines on cancer-specific treatment thresholds are limited, and major knowledge gaps still exist in fracture risk and fracture risk assessment in patients with cancer. Despite the limitations of current knowledge on fracture risk assessment and treatment thresholds in patients with cancer, clinicians must consider the additive effects of bone damaging factors to which these patients are exposed and their premorbid fracture risk profile. Pharmacologic treatment should be offered as per cancer-specific guidelines when available, or per local general osteoporosis guidelines, in accordance with clinical judgment and patient preferences.

Effect of Teriparatide on Subsequent Fracture and Bone Mineral Density in 47 Women with Pregnancy- and Lactation-associated Osteoporosis and Vertebral Fractures

Introduction Pregnancy- and lactation-associated osteoporosis (PLO) with predominantly vertebral fractures is a rare but severe disease which can occur in the last trimester of pregnancy or postpartum. The aim of the present study was to assess the impact of teriparatide on subsequent fractures and bone mineral density (BMD) in patients with PLO.

Materials and Methods A total of 47 patients with PLO and postpartum spinal fractures (mean: 4 fractures) undergoing treatment with teriparatide were investigated. The data collection period was set between 2006 and 2018. All patients received a subcutaneous injection of 20 µg teriparatide once a day for 24 months as well as individually adapted vitamin D supplementation. After 24 months of treatment, all women received no further treatment and either had regular menstrual cycles or took oral contraceptives. Fractures were confirmed by X-ray or MRI. Changes in BMD from baseline were examined using serial DXA measurements.

Results After 24 months of teriparatide treatment, we could demonstrate an increase in BMD at the lumbar spine, femoral neck and total hip of + 30.1%, + 11.7% and + 12.2% respectively (p < 0.001 for all). At 12 months after cessation of treatment, BMD remained stable compared to the 24-month measurements at the lumbar spine, femoral neck and total hip which showed non-significant changes of + 1.4%, + 2.6% and + 4.1% respectively. Out of the 47 patients with PLO with a mean of 4 existing fractures, 4 patients (7.8%) sustained a subsequent fracture, two after 3 – 5 months of treatment and two at > 6 months of treatment.

Conclusion 24 months of treatment with teriparatide in women with PLO and multiple vertebral fractures significantly increased BMD, predominantly BMD of the spine. As patients were premenopausal, there was no significant decrease in BMD in the following 12 months after cessation of treatment.

Therapeutic Options in the Management of Aromatase Inhibitor-Associated Bone Loss

BACKGROUND

Breast cancer is the most commonly occurring cancer in women worldwide. Early breast cancer is a kind of invasive neoplasm that has not proliferated beyond the breast or the axillary lymph nodes. Current therapeutic strategies for breast cancer mainly include local therapies such as surgery or radiotherapy and systemic therapies like chemotherapy, endocrine, and targeted therapy.Nowadays, the adjuvant treatment for hormone receptor-positive early breast cancer in postmenopausal women remains the main effective systemic therapy which can improve disease-free survival and overall survival; it involves several endocrine treatment regimens including selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs), or a combination of them. AIs have been shown to be more effective in preventing recurrence in postmenopausal women with early breast cancer when compared with tamoxifen, thus representing the standard of care for adjuvant endocrine therapy. Although AIs are usually well-tolerated, they can have some side effects. Apart from the appearance of arthralgias or myalgias and cardiovascular events, AI therapies, reducing already low endogenous postmenopausal estradiol levels, cause increased bone loss and increase fracture risk in postmenopausal women.

OBJECTIVES

To evaluate the therapeutic options in the management of aromatase inhibitor-associated bone loss (AIBL).

METHODS

We reviewed the current literature dealing with different therapeutic options in the treatment of AIBL.

RESULTS

Clinical practice guidelines recommend a careful evaluation of skeletal health in all women with breast cancer before AI therapy initiation. Adequate calcium and vitamin D intake have also been suggested. Pharmacological attempts to minimize AI-related bone loss have focused on the use of antiresorptive agents, such as bisphosphonates and denosumab, to protect bone integrity and reduce the risk of fractures. Furthermore, clinical trials have shown that by making the bone microenvironment less susceptible to breast cancer metastasis, these drugs are able to increase disease-free survival.

CONCLUSIONS

AI, thatare the pillar of the systemic treatment for patients with hormone receptor-positive breast cancer, are associated with different side effects, and in particular osteoporosis and fractures. Both bisphosphonates and denosumab are able to prevent this negative effect.

Effect of tamoxifen with or without gonadotropin-releasing hormone analog on DXA values in women with breast cancer

The purpose of this study was to compare the changes in DXA values including trabecular bone score (TBS) and bone mineral density (BMD) of lumbar spine (LS) and femur according to the hormone therapies including tamoxifen (TMXF) treatment with or without gonadotropin releasing hormone analog (GnRH analog) in women with breast cancer. We enrolled 119 women with breast cancer who had undergone breast-conserving surgery or mastectomy followed by TMXF treatment for postmenopausal women (TMXF group, n = 63, 52.9%) or by combination therapy of TMXF combined with GnRH analog for premenopausal women (TMXF + GnRH group, n = 56, 47.1%) from December 2013 to December 2017. The median follow-up period was 13 months (interquartile range [IQR], 12.0–14.75) for TMXF group and 13.5 months (IQR, 12.00–16.00) for TMXF + GnRH group, respectively. Patients did not receive bone-modifying therapy. The baseline dual-energy X-ray absorptiometry (DXA) scan before breast cancer surgery and follow-up DXA during hormone therapy. Comparing the first and follow-up DXA results, BMD in LS were significantly decreased in both TMXF (P < 0.001, mean difference: − 0.06) and TMXF + GnRH (P < 0.001, mean difference: − 0.09) groups. BMD values of femoral neck (P = 0.0011, mean difference: − 0.01) and total femur (P < 0.001, mean difference: − 0.03) was significantly changed between the baseline and follow-up DXA in TMXF + RnRH group. In the TMX group, a significant changed occurred in the BMD in total femur (P < 0.001, mean difference: − 0.030) but not the BMD of femoral neck (P = 0.095, mean difference: − 0.007). Regarding TBS, no significant change was found in the TMXF (P = 0.574, mean difference: − 0.004) group, whereas there was a significant decrease in TBS in the TMXF + GnRH (P < 0.001, mean difference: − 0.02) group during follow-up. TBS is more sensitive in reflecting the bone microarchitecture changes by TMXF or GnRH agonist in breast cancer patients than BMD. This finding demonstrates that TBS can be a useful parameter to detect bone microarchitectural changes in clinical applications.

Representation of CYP3A4, CYP3A5 and UGT1A4 Polymorphisms within Croatian Breast Cancer Patients' Population

Single nucleotide polymorphism (SNP) in genes encoding drug-metabolizing enzymes (DME) could have a critical role in individual responses to anastrozole. Frequency of CYP3A4*1B, CYP3A5*3 and UGT1A4*2 SNPs in 126 Croatian breast cancer (BC) patients and possible association with anastrozole-induced undesirable side effects were analyzed. Eighty-two postmenopausal patients with estrogen receptor (ER)-positive BC treated with anastrozole and 44 postmenopausal ER-positive BC patients before hormonal adjuvant therapy were included in the study. Genomic DNA was genotyped by TaqMan Real-Time PCR. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry. The homozygotes for the variant G allele of CYP3A5*3 were predominant (88%), and the homozygotes for the reference A allele were not detected. While homozygotes for the variant G allele of CYP3A4*1B were not detected, predominantly wild type homozygotes for A allele (94%) were present. CYP3A4*1B and CYP3A5*3 SNPs were in 84.3% linkage disequilibrium (D' = 0.843) and 95.1% (D' = 0.951) in group treated with anastrozole and w/o treatment, respectively. Homozygotes for the A allele of UGT1A4*2 were not detected in our study groups. Although the variant CYP3A5*3 allele, which might result in poor metabolizer phenotype and more pronounced side effects, was predominant, significant association with BMD changes induced by anastrozole were not confirmed.

Baseline bone health status in multi-ethnic South African postmenopausal breast cancer patients at initiation of aromatase inhibitor therapy: A descriptive study

Introduction

Osteoporosis (OP) risk factor assessment and bone mineral density (BMD) testing are frequently omitted at baseline in aromatase inhibitor (AI) studies, which may lead to misinterpretation of AI associated bone loss. The present study describes bone health of South African postmenopausal women of predominantly Mixed Ancestry, prior to AI treatment.

Methods

This descriptive baseline study, nested in a prospective AI cohort study, included postmenopausal women with endocrine sensitive breast cancer, aged 50 to 80 years. A baseline questionnaire documented demographic-, medical-, lifestyle- and fracture history. Body weight was assessed clinically, and body composition and BMD measured via dual energy absorptiometry (DXA). Data was analysed in STATA 14 using descriptive and inferential statistics.

Results

101 participants were recruited, with a mean age of 61±7 years. Nearly a third (n = 32) of women at baseline fulfilled global criteria for bone protection (BMD T-score ≥-2SD (n = 18); BMD T-score -1.5SD to < -2SD with risk factors (n = 14). Lower body weight, body mass index (BMI), fat mass index and lean mass index were significantly associated with the participants with a BMD measurement in keeping with a diagnosis of OP (p <0.001). Low vitamin D was present in 93% of the cohort tested (n = 95), whilst deficient vitamin D status (<20ng/ml) was documented in 52 women (55%).

Conclusions

In this study, a third of postmenopausal women considered for AI therapy fulfilled international criteria for bone protective pharmacological intervention. This emphasizes the need for clinical risk and BMD assessment in postmenopausal breast cancer patients at baseline. Body composition and bone health associations highlight bone fragility associated with lower body weight.

DIAGNOSIS OF ENDOCRINE DISEASE: Evaluation of bone fragility in endocrine disorders

An underlying disease affecting bone health is present in up to 40% and 60% of osteoporotic post-menopausal women and men respectively. Among the disorders leading to a secondary form of osteoporosis, the endocrine diseases are highly represented. A frequent finding in patients affected with an endocrine-related forms of bone disease is that the skeletal fragility is partially independent of the bone density, since the fracture risk in these patients is related more to a reduction of bone quality than to a decrease of bone mass. As a consequence, bone mineral density evaluation by dual-X-ray Absorptiometry may be inadequate for establishing the risk of fracture in the setting of the endocrine-related forms of osteoporosis. In the recent years several attempts to non-invasively estimating bone quality have been done. Nowadys, some new tools are available in the clinical practice for optimizing the fracture risk estimation in patients with endocrine disorders. The aim of this review is to summarise the evidences regarding the role of the different imaging tools for evaluating bone density and bone quality in the most frequent forms of endocrine-related osteoporosis, such as obesity, diabetes, acromegaly, thyrotoxicosis, primary hyperparathyroidism, hypercortisolism and hypogonadism. For each of these disorders, data regarding both the current available tools and the future possible new techniques for assessing bone fragility in patients with endocrine diseases are reported.

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.

Interdisciplinary Screening, Diagnosis, Therapy and Follow-up of Breast Cancer. Guideline of the DGGG and the DKG (S3-Level, AWMF Registry Number 032/045OL, December 2017) - Part 2 with Recommendations for the Therapy of Primary, Recurrent and Advanced Breast Cancer

Purpose The aim of this official guideline coordinated and published by the German Society for Gynecology and Obstetrics (DGGG) and the German Cancer Society (DKG) was to optimize the screening, diagnosis, therapy and follow-up care of breast cancer. Method The process of updating the S3 guideline published in 2012 was based on the adaptation of identified source guidelines. They were combined with reviews of evidence compiled using PICO (Patients/Interventions/Control/Outcome) questions and with the results of a systematic search of literature databases followed by the selection and evaluation of the identified literature. The interdisciplinary working groups took the identified materials as their starting point and used them to develop suggestions for recommendations and statements, which were then modified and graded in a structured consensus process procedure. Recommendations Part 2 of this short version of the guideline presents recommendations for the therapy of primary, recurrent and metastatic breast cancer. Loco-regional therapies are de-escalated in the current guideline. In addition to reducing the safety margins for surgical procedures, the guideline also recommends reducing the radicality of axillary surgery. The choice and extent of systemic therapy depends on the respective tumor biology. New substances are becoming available, particularly to treat metastatic breast cancer.

Association of Wnt Inhibitors, Bone Mineral Density and Lifestyle Parameters in Women with Breast Cancer Treated with Anastrozole Therapy

AIM

To determine the levels of Wnt inhibitors in patients treated with aromatase inhibitors (AIs) prior to therapy and to investigate their association with bone mineral density (BMD) and lifestyle parameters.

METHODS

137 breast cancer patients were divided into a group treated with 1 mg of anastrozole and a group w/o anastrozole therapy. Serum concentrations of sclerostin and dickkopf1 (DKK1) were measured by ELISA. BMD was measured by dual-energy X-ray absorptiometry (DXA). Lifestyle factors were investigated by a self-reported questionnaire.

RESULTS

Sclerostin was significantly higher in the AI-treated group (31.8 pmol/L vs. 24.1 pmol/L; p < 0.001), whereas DKK1 was significantly lower in the AI-treated group (24.3 pmol/L vs. 26.02 pmol/L; p < 0.001). Total hip and femoral neck BMD were significantly lower in the AI-treated group.

CONCLUSION

AI treatment was associated with increased levels of sclerostin and decreased levels of DKK1.

ACR Appropriateness Criteria® Osteoporosis and Bone Mineral Density

Osteoporosis is a considerable public health risk, with 50% of women and 20% of men >50 years of age experiencing fracture, with mortality rates of 20% within the first year. Dual x-ray absorptiometry (DXA) is the primary diagnostic modality by which to screen women >65 years of age and men >70 years of age for osteoporosis. In postmenopausal women <65 years of age with additional risk factors for fracture, DXA is recommended. Some patients with bone mineral density above the threshold for treatment may qualify for treatment on the basis of vertebral body fractures detected through a vertebral fracture assessment scan, a lateral spine equivalent generated from a commercial DXA machine. Quantitative CT is useful in patients with advanced degenerative bony changes in their spines. New technologies such as trabecular bone score represent an emerging role for qualitative assessment of bone in clinical practice. It is critical that both radiologists and referring providers consider osteoporosis in their patients, thereby reducing substantial morbidity, mortality, and cost to the health care system. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

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 Trabecular Bone Score (TBS) Complements DXA and the FRAX as a Fracture Risk Assessment Tool in Routine Clinical Practice

PURPOSE OF THE REVIEW

There is an increasing body of evidence that the trabecular bone score (TBS), a surrogate of bone microarchitecture extracted from spine DXA, could play an important role in the management of patients with osteoporosis or at risk of fracture. The current paper reviews this published body of scientific literature on TBS and answers the most relevant clinical questions.

RECENT FINDINGS

TBS has repeatedly been proven to be predictive of fragility fractures, current and future, and this is largely independent of BMD, CRF, and the FRAX, and when used in conjunction with any one of these measures, it consistently enhances their accuracy. There also is a growing body of evidence indicating that the TBS has particular advantages over BMD for specific causes of increased fracture risk, like chronic corticosteroid excess, type-2 diabetes, and chronic kidney disease, and patients being treated with anti-aromatase and primary hyperparathyroidism, conditions wherein BMD readings are often misleading. TBS enhances performance of the FRAX tool, where its greatest utility appears to lie in its ability to accurately classify those patients whose BMD level lies close to the intervention threshold, aiding in decisions on whether treatment is warranted or not. Furthermore, TBS has also particular advantages over BMD in secondary osteoporosis. While the role of TBS with monitoring could be important as the different molecules impact logically TBS to various degrees, large clinical trials are still needed.

Postmenopausal Breast Cancer, Aromatase Inhibitors, and Bone Health: What the Surgeon Should Know

Breast cancer, as the most common malignancy in women, remains a major public health issue despite countless advances across decades. Endocrine therapy is the cornerstone of treatment of the hormone-sensitive subtype of breast cancer. The use of aromatase inhibitors (AIs) in the postmenopausal women has extended the survival beyond that of Tamoxifen, but harbors a subset of side effects, most notably accelerated bone loss. This, however, does not occur in all women undergoing treatment. It is vital to identify susceptible patients early, to limit such events, employ early treatment thereof, or alter drug therapy. International trials on AIs, predominantly performed in North American and European females, provide little information on what to expect in women in developing countries. Here, surgeons often prescribe and manage endocrine therapy. The prescribing surgeon should be aware of the adverse effect of the endocrine therapy and be able to attend to side effects. This review highlights clinical and biochemical factors associated with decrease in bone mineral density in an, as yet, unidentified subgroup of postmenopausal women. In the era of personalized medical care, appropriate management of bone health by surgeons based on these factors becomes increasingly important.

Effects of Teriparatide, Denosumab, or Both on Spine Trabecular Microarchitecture in DATA-Switch: a Randomized Controlled Trial

In postmenopausal women, 2 yr of combined teriparatide and denosumab increases bone mineral density more than either drug alone, and switching from either combination or teriparatide to denosumab for an additional 2 yr further increases bone mineral density. Conversely, switching from denosumab to teriparatide results in transient bone loss. The effects of these interventions on spine microarchitecture are unknown. In the DATA and DATA-Switch studies, 94 postmenopausal osteoporotic women were randomized to receive 24 mo of teriparatide (20 µg daily), denosumab (60 mg every 6 mo), or both. Then, women originally assigned to 24 mo of teriparatide received 24 mo of denosumab, whereas subjects originally randomized to 24 mo of denosumab received 24 mo of teriparatide. Subjects who received both drugs received an additional 24 mo of denosumab alone. Spine trabecular bone score (TBS, a gray-level textural assessment of bone microarchitecture) was measured blinded from treatment groups using images from 2-dimensional dual-energy X-ray absorptiometry spine scans at 0, 12, 24, 30, 36, and 48 mo in 65 women who had posterior-anterior spine dual-energy X-ray absorptiometry images suitable for TBS analysis. After 24 mo, TBS increased by 2.7 ± 4.7% in the teriparatide group (p = 0.009 vs baseline), by 1.8 ± 5.0% in the denosumab group (p = 0.118 vs baseline), and by 4.5 ± 6.7% in the combination group (p = 0.017 vs baseline), with no significant between-group differences. In the 6 mo after the treatments were switched (months 24-30), TBS continued to increase in the combination-to-denosumab and teriparatide-to-denosumab groups but decreased by -1.1 ± 4.0% in the denosumab-to-teriparatide group (p < 0.05 vs other groups). After 48 mo, compared to month 0, TBS increased by 5.1 ± 5.8% in the teriparatide-to-denosumab group, by 3.6 ± 4.2% in the denosumab-to-teriparatide group, and by 6.1 ± 4.7% in the combination-to-denosumab group (p < 0.001 vs baseline for all groups, p = not significant for between-group differences). Switching from teriparatide to denosumab also increased spine TBS. Conversely, switching from denosumab to teriparatide transiently degraded spine trabecular microarchitecture, the clinical consequences of which require further study.

Quantitative ultrasound and DXA measurements in aromatase inhibitor-treated breast cancer women receiving denosumab

PURPOSE

Denosumab has been proven to reduce fracture risk in breast cancer (BC) women under aromatase inhibitors (AIs). Quantitative ultrasound (QUS) provides information on the structure and elastic properties of bone. Our aim was to assess bone health by phalangeal QUS and by dual-energy X-ray absorptiometry (DXA), and to evaluate bone turnover in AIs-treated BC women receiving denosumab.

METHODS

35 Postmenopausal BC women on AIs were recruited (mean age 61.2 ± 4.5 years) and treated with denosumab 60 mg administered subcutaneously every 6 months. Phalangeal QUS parameters [Amplitude Dependent Speed of Sound (AD-SoS), Ultrasound Bone Profile Index (UBPI), Bone Transmission Time (BTT)] and DXA at lumbar spine and femoral neck were performed. Serum C-telopeptide of type 1 collagen (CTX) and bone-specific alkaline phosphatase (BSAP) were also measured. The main outcomes were compared with a control group not receiving denosumab (n = 39).

RESULTS

In patients treated with denosumab, differently from controls, QUS and DXA measurements improved after 24 months, and a reduction of CTX and BSAP was detected at 12 and 24 months in comparison to baseline (P < 0.05). The percent changes (Δ) of QUS measurements were significantly associated with ΔBMD at femoral neck, and ΔCTX and ΔBSAP were associated with ΔBMD at lumbar spine (r = -0.39, P = 0.02; r = -0.49, P = 0.01, respectively).

CONCLUSIONS

Denosumab preserves bone health as assessed by phalangeal QUS and DXA. Since inexpensive and radiation-free, phalangeal QUS may be considered in the follow-up of AIs-treated BC women receiving denosumab.

Use of Trabecular Bone Score (TBS) as a Complementary Approach to Dual-energy X-ray Absorptiometry (DXA) for Fracture Risk Assessment in Clinical Practice

Osteoporosis is a common bone disease characterized by low bone mass and altered bone microarchitecture, resulting in decreased bone strength with an increased risk of fractures. In clinical practice, physicians can assess the risk of fracture for a patient based on several risk factors. Some such as age, weight, and history of fractures after 50 years of age, parental fracture, smoking status, and alcohol intake are incorporated into FRAX, an assessment tool that estimates the 10-year probability of hip fracture and major osteoporotic fractures based on the individual's risk factors profile. The diagnosis of osteoporosis is currently based on bone mineral density (BMD) assessed by dual-energy X-ray absorptiometry scans. Among other widely recognized limitations of BMD is that BMD considers only the density of the bone and fails in measuring bone microarchitecture, for which novel techniques, such as trabecular bone score (TBS), have been developed. TBS is a texture parameter related to bone microarchitecture that may provide skeletal information that is not captured from the standard BMD measurement. Several studies have examined the value of TBS on predicting osteoporotic fractures. Our study aimed to summarize a review of the current scientific literature with focus on fracture risk assessment and to present both its findings and its conclusions regarding how and when TBS should be used. The existing literature indicates that low lumbar spine TBS is associated with a history of fracture and the incidence of new fracture. The effect is largely independent of BMD and of sufficient magnitude to enhance risk stratification with BMD. The TBS effect is also independent of FRAX, with likely greatest utility for those individuals whose BMD levels lie close to an intervention threshold. The clinical and scientific evidence supporting the use of TBS, with the ability of this technology to be seamlessly integrated into a daily workflow, makes TBS an attractive and useful clinical tool for physicians to improve patient management in osteoporosis. Further research is ongoing and necessary to further clarify the role of TBS in additional specific disorders.

Assessing fracture risk in early stage breast cancer patients treated with aromatase-inhibitors: An enhanced screening approach incorporating trabecular bone score

INTRODUCTION

Aromatase-inhibitors (AIs) are commonly used for treatment of patients with hormone-receptor positive breast carcinoma, and are known to induce bone density loss and increase the risk of fractures. The current standard-of-care screening tool for fracture risk is bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA). The fracture risk assessment tool (FRAX®) may be used in conjunction with BMD to identify additional osteopenic patients at risk of fracture who may benefit from a bone-modifying agent (BMA). The trabecular bone score (TBS), a novel method of measuring bone microarchitecture by DXA, has been shown to be an independent indicator of increased fracture risk. We report how the addition of TBS and FRAX®, respectively, to BMD contribute to identification of elevated fracture risk (EFR) in postmenopausal breast cancer patients treated with AIs.

METHODS

100 patients with early stage hormone-positive breast cancer treated with AIs, no prior BMAs, and with serial DXAs were identified. BMD and TBS were measured from DXA images before and following initiation of AIs, and FRAX® scores were calculated from review of clinical records. EFR was defined as either: BMD ≤-2.5 or BMD between -2.5 and -1 plus either increased risk by FRAX® or degraded microstructure by TBS.

RESULTS

At baseline, BMD alone identified 4% of patients with EFR. The addition of FRAX® increased detection to 13%, whereas the combination of BMD, FRAX® and TBS identified 20% of patients with EFR. Following AIs, changes in TBS were independent of changes in BMD. On follow-up DXA, BMD alone detected an additional 1 patient at EFR (1%), whereas BMD+ FRAX® identified 3 additional patients (3%), and BMD+FRAX®+TBS identified 7 additional patients (7%).

CONCLUSIONS

The combination of FRAX®, TBS, and BMD maximized the identification of patients with EFR. TBS is a novel assessment that enhances the detection of patients who may benefit from BMAs.

Longitudinal Change in Trabecular Bone Score during and after Treatment of Osteoporosis in Postmenopausal Korean Women

BACKGROUND

The aim of this study was to evaluate the longitudinal changes of trabecular bone score (TBS) during and after bisphosphonate (BP) treatment in postmenopausal Korean women with osteoporosis.

METHODS

We analyzed 191 patients who took BP and underwent bone mineral density (BMD) test for the period from January 2010 to December 2015. The mean follow up period during treatment and after treatment was 22.8 months and 18 months, respectively. The TBS and BMD values were evaluated by the percent changes relative to the baseline.

RESULTS

In 191 patients, who treated with BPs, L-spine BMD increased 3.65±0.5% and TBS increased 0.26±0.4% from baseline during first 1 year. At 2 to 4 years, the changes of BMD and TBS from baseline gradually increased up to 9.3±3.25% and 2.69±0.98% and both results showed statistically significant correlation. In 86 patients who stopped BPs, L-spine BMD decreased -0.54±1.07% and TBS increased 0.33±1.96% from baseline during 3 years follow up period.

CONCLUSIONS

Lumbar spine TBS increase over time with BPs treatment although the changes were less than that of BMD. Also, it preserve for years after stopping treatment, as the changes of lumbar spine BMD. The results of BMD and TBS showed significant correlation during treatment but not during drug withdrawal.

Long-term effect of aromatase inhibitors on bone microarchitecture and macroarchitecture in non-osteoporotic postmenopausal women with breast cancer

In non-osteoporotic postmenopausal women with breast cancer, aromatase inhibitors (AIs) negatively affected bone mineral density (BMD), lumbar spine trabecular bone score (TBS) as a bone microarchitecture index, and hip geometry as a bone macroarchitecture index.

INTRODUCTION

AIs increase the risk of fracture in patients with breast cancer. Therefore, we aimed to evaluate the long-term skeletal effects of AIs in postmenopausal women with primary breast cancer.

METHODS

We performed a retrospective longitudinal observational study in non-osteoporotic patients with breast cancer who were treated with AIs for ≥3 years (T-score >-2.5). Patients with previous anti-osteoporosis treatment or those who were given bisphosphonate during AI treatment were excluded from the analysis. We serially assessed BMD, lumbar spine TBS, and hip geometry using dual-energy X-ray absorptiometry.

RESULTS

BMD significantly decreased from baseline to 5 years at the lumbar spine (-6.15%), femur neck (-7.12%), and total hip (-6.35%). Lumbar spine TBS also significantly decreased from baseline to 5 years (-2.12%); this change remained significant after adjusting for lumbar spine BMD. The annual loss of lumbar spine BMD and TBS slowed after 3 and 1 year of treatment, respectively, although there was a relatively constant loss of BMD at the femur neck and total hip for up to 4 years. The cross-sectional area, cross-sectional moment of inertia, minimal neck width, femur strength index, and section modulus significantly decreased, although the buckling ratio increased over the treatment period (all P < 0.001); these changes were independent of total hip BMD.

CONCLUSIONS

Long-term adjuvant AI treatment negatively influenced bone quality in addition to BMD in patients with breast cancer. This study suggests that early monitoring and management are needed in non-osteoporotic patients with breast cancer who are starting AIs.

Trabecular Bone Score: A New DXA-Derived Measurement for Fracture Risk Assessment

Trabecular bone score (TBS) is a novel method that assesses skeletal texture from spine dual-energy X-ray absorptiometry (DXA) images. TBS improves fracture-risk prediction beyond that provided by DXA bone mineral density (BMD) and clinical risk factors, and can be incorporated to the Word Health Organization Fracture Risk Assessment tool (FRAX®) to enhance fracture prediction. There is insufficient evidence that TBS can be used to monitor treatment with bisphosphonates. TBS may be particularly helpful to assess fracture risk in diabetes. This article reviews technical and clinical aspects of TBS and its potential utility as a clinical tool to predict fracture risk.

TBS and BMD at the end of AI-therapy: A prospective study of the B-ABLE cohort

INTRODUCTION

Patients with breast cancer under aromatase inhibitor (AI) treatment often develop osteoporosis and their average bone loss rate is twice that of natural reduction during menopause, increasing fracture risk. As the current diagnostic technique based on bone mineral density (BMD) provides no information on bone quality, the Trabecular Bone Score (TBS) has been proposed to reflect bone microarchitecture status. The present study was designed to assess prospective changes in TBS and lumbar spine (LS) BMD in postmenopausal women with breast cancer at completion of AI treatment.

METHODS

B-ABLE is a prospective cohort of 735 women with breast cancer treated with AIs according to American Society of Clinical Oncology recommendations: 5years of AI starting within 6weeks post-surgery or 1month after the last cycle of chemotherapy (5y-AI group), or switching to an AI to complete 5-year therapy after 2-3years of tamoxifen (pTMX-AI group). Patients with osteoporosis were treated with oral bisphosphonates (BP). TBS and LS-BMD changes at completion of AI therapy were evaluated by Student t-test for paired samples. Pearson correlation coefficients were computed for correlations between LS-BMD and TBS.

RESULTS

AI treatment was completed by 277 women. Of these, 70 (25.3%) were allocated to BP therapy. The non-BP-treated patients (74.7%) showed significant decreases in TBS (-2.94% in pTMX-AI and -2.93% in 5y-AI groups) and in LS-BMD (-4.14% in pTMX-AI and -2.28% in 5y-AI groups) at the end of AI treatment. In BP-treated patients, TBS remained stable at the end of AI treatment, whereas LS-BMD showed significant increases (+2.30% in pTMX-AI and +5.33% in 5y-AI groups). Moderate associations between TBS and LS-BMD values at baseline and at the end of AI treatment (r=0.4; P<0.001) were observed. At the end of treatment, changes in spine BMD and TBS were weakly correlated (r=0.1, P<0.01).

CONCLUSIONS

AI therapy induces significant decreases in TBS, comparable to BMD loss. BP-treated patients maintained TBS values, whereas BMD increased. AI treatment leads to deterioration of bone microarchitecture, which seems to be attenuated by BP therapy.

Risedronate may preserve bone microarchitecture in breast cancer survivors on aromatase inhibitors: A randomized, controlled clinical trial

This study provides preliminary evidence that risedronate not only preserves BMD but may also attenuate the loss of bone microarchitecture over 2years during a time of accelerated bone loss in post-menopausal breast cancer survivors on aromatase inhibitors.

INTRODUCTION

Accelerated bone loss and elevated fracture risk are associated with the use of aromatase inhibitors (AIs) in women with breast cancer. We previously reported that the oral bisphosphonate, risedronate, can maintain bone mineral density (BMD) in the hip and spine over 2-years in post-menopausal breast cancer survivors on AIs. In this study, we examined whether oral bisphosphonates can also preserve bone microarchitecture as measured by the trabecular bone score (TBS) in this population.

METHODS

This 2-year randomized, double-blind, placebo-controlled trial included postmenopausal women over age 55 with breast cancer on an AI who had low bone mass. Participants provided informed consent and were randomized to risedronate 35mg once weekly or placebo. We examined 12- and 24-month changes in spine TBS, analyzed using linear mixed models.

RESULTS

One-hundred and nine women with a mean age of 70.5years were included in the analysis. In the placebo group, BMD declined at the spine and hip over the 24-month period but was preserved in the active treatment group (data previously reported). TBS declined in the placebo group by -2.1% and -2.3% at 12- and 24-months, respectively (p<0.005). The TBS percent change in bisphosphonate-treated patients was -0.9% and -1.3% at 12 and 24-months but did not reach statistical significance (p=0.24 and 0.14). The 12- and 24-month between-group differences were 0.9 (p=0.38) and 0.8 (p=0.44) percentage points. TBS change correlated with spine BMD changes in the placebo group at 12- and 24-months (r=0.33 and 0.34, p<0.01) but not in the active treatment group.

CONCLUSION

The oral bisphosphonate risedronate preserves BMD and may attenuate loss of bone microarchitecture over 2years during a time of accelerated bone loss in breast cancer survivors on AIs, but more definitive evidence is needed.

Trabecular bone score as a skeletal fragility index in acromegaly patients

SUMMARY

Lumbar spine trabecular bone score (TBS) was significantly decreased in active acromegaly patients. TBS may be useful to assess the skeletal fragility in acromegaly in which bone mineral density (BMD) is not sufficient to represent bone strength and explain the high incidence of fragility fractures in acromegaly patients.

INTRODUCTION

Although the data on BMD are controversial, patients with acromegaly have an increased risk of fragility fracture. We examined the lumbar spine TBS to explain the skeletal deterioration in acromegaly patients.

METHODS

We included 14 men and 19 women acromegaly patients who underwent dual-energy X-ray absorptiometry at the time of diagnosis from 2000 to 2014 at Seoul National University Hospital. Ninety-nine age-, sex- and body mass index-matched controls were recruited. Biochemical parameters, lumbar spine TBS, and BMD at all sites were measured. Gonadal status was evaluated at diagnosis.

RESULTS

Lumbar spine TBS was lower in acromegaly patients than in controls in both genders (1.345 ± 0.121 vs. 1.427 ± 0.087, P = 0.005 in men; 1.356 ± 0.082 vs. 1.431 ± 0.071, P = 0.001 in women). In contrast, BMD at all sites did not differ between the two groups. Hypogonadal acromegaly patients (men, n = 9; women, n = 12) had lower TBS values compared with controls both in men and women (all P < 0.05), although BMD at all sites were similar for the two groups. In eugonadal acromegaly patients, lumbar spine TBS was lower than in women controls only (P = 0.041).

CONCLUSIONS

Skeletal microarchitecture was deteriorated in acromegaly patients as assessed by TBS, which seems to be a consequence of growth hormone excess as well as hypogonadism, especially in women.

Predictors of trabecular bone score in school children

Trabecular bone score (TBS) is a DXA-based tool that assesses bone texture and reflects microarchitecture. It has been shown to independently predict the risk of osteoporotic fracture in the elderly. In this study, we investigated the determinants of TBS in adolescents.

INTRODUCTION

TBS is a gray-level textural measurement derived from lumbar spine DXA images. It appears to be an index of bone microarchitecture that provides skeletal information additional to the standard BMD measurement and clinical risk factors. Our objectives were to characterize the relationship between TBS and both age and pubertal stages and identify other predictors in adolescents.

METHODS

We assessed TBS by reanalyzing spine DXA scan images obtained from 170 boys and 168 girls, age range 10-17 years, gathered at study entry and at 1 year, using TBS software. The results are from post hoc analyses obtained using data gathered from a prospective randomized vitamin D trial. Predictors of TBS were assessed using t test or Pearson's correlation and adjusted using regression analyses, as applicable.

RESULTS

The mean age of the study population was 13.2 ± 2.1 years, similar between boys and girls. Age, height, weight, sun exposure, spine BMC and BMD, body BMC and BMD, and lean and fat mass are all significantly correlated with TBS at baseline (r = 0.20-0.75, p < 0.035). Correlations mostly noted in late-pubertal stages. However, after adjustment for BMC, age remained an independent predictor only in girls.

CONCLUSIONS

In univariate exploratory analyses, age and pubertal stages were determinants of TBS in adolescents. Studies to investigate predictors of TBS and to investigate its value as a prognostic tool of bone fragility in the pediatric population are needed.

Trabecular bone score (TBS) as a new complementary approach for osteoporosis evaluation in clinical practice

Trabecular bone score (TBS) is a recently-developed analytical tool that performs novel grey-level texture measurements on lumbar spine dual X-ray absorptiometry (DXA) images, and thereby captures information relating to trabecular microarchitecture. In order for TBS to usefully add to bone mineral density (BMD) and clinical risk factors in osteoporosis risk stratification, it must be independently associated with fracture risk, readily obtainable, and ideally, present a risk which is amenable to osteoporosis treatment. This paper summarizes a review of the scientific literature performed by a Working Group of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis. Low TBS is consistently associated with an increase in both prevalent and incident fractures that is partly independent of both clinical risk factors and areal BMD (aBMD) at the lumbar spine and proximal femur. More recently, TBS has been shown to have predictive value for fracture independent of fracture probabilities using the FRAX® algorithm. Although TBS changes with osteoporosis treatment, the magnitude is less than that of aBMD of the spine, and it is not clear how change in TBS relates to fracture risk reduction. TBS may also have a role in the assessment of fracture risk in some causes of secondary osteoporosis (e.g., diabetes, hyperparathyroidism and glucocorticoid-induced osteoporosis). In conclusion, there is a role for TBS in fracture risk assessment in combination with both aBMD and FRAX.

Fracture Risk Prediction by Non-BMD DXA Measures: the 2015 ISCD Official Positions Part 2: Trabecular Bone Score

Bone mineral density (BMD) as measured by dual-energy X-ray absorptiometry (DXA) is the gold standard for the diagnosis and management of osteoporosis. However, BMD explains only 60%-80% of bone strength, and a number of skeletal features other than BMD contribute to bone strength and fracture risk. Advanced imaging modalities can assess some of these skeletal features, but compared to standard DXA, these techniques have higher costs and limited accessibility. A major challenge, therefore, has been to incorporate in clinical practice a readily available, noninvasive technology that permits improvement in fracture-risk prediction beyond that provided by the combination of standard DXA measurements and clinical risk factors. To this end, trabecular bone score (TBS), a gray-level textural index derived from the lumbar spine DXA image, has been investigated. The purpose of this International Society for Clinical Densitometry task force was to review the evidence and develop recommendations on how to incorporate TBS in clinical practice. Clinical applications of TBS for fracture risk assessment, treatment initiation, monitoring of treatment, and use of TBS in special conditions related to greater fracture risk, were addressed. We present the official positions approved by an expert panel following careful review of the recommendations and evidence presented by the TBS task force.

Cancer Treatment-Induced Bone Loss in women with breast cancer

Osteoporosis is one of the most frequent diseases in postmenopausal women, leading to an increased fracture risk due to the physiologic loss of the bone protective effects of estrogen. Hereby, several risk factors for fracture such as prevalent fracture, low bone mineral density (BMD), age, low body mass index, family history, tendency to falls, smoking, use of SSRIs, glucocorticoid use etc. have been identified. In addition, the further reduction in endogenous estrogens with chemotherapy (CHT), GnRH analoga or aromatase inhibitors (AIs) continuously increases fracture risk. Breast cancer (BC) on the other hand is the most frequent cancer type in women. Recent reports indicate a continuous increased incidence, whereas mortality, due to early diagnosis and treatment improvements, is decreasing. Dependent on specific tumor characteristics, radiation, CHT, antibody treatment as well as endocrine treatment have been included into the adjuvant clinical treatment setting. Some but not all of these cancer-specific treatments interfere with bone turnover, leading to an accelerated bone loss referred to as cancer treatment-induced bone loss (CTIBL). Whereas CHT leads to an unspecific increase in bone resorption, AI reduces residual serum endogenous estrogen level and is associated with a decrease in BMD and increased fracture risk. Independent of the type of AI administered, bone loss is 2-3-fold increased compared with healthy, age-matched postmenopausal controls. Therefore, several guidelines have emerged to help managing CTIBL in women with BC including strategies to identify and treat those at highest risk for fractures. This review summarizes the current knowledge on CTIBL and fracturing risk and indicates preventative strategies.

Effects of zoledronic acid versus placebo on bone mineral density and bone texture analysis assessed by the trabecular bone score in premenopausal women with breast cancer treatment-induced bone loss: results of the ProBONE II substudy

Changes in bone mineral density (BMD) and trabecular bone score (TBS) were assessed in 70 patients who received either zoledronate (ZOL) (n = 34) or placebo (n = 36) for 2 years. In premenopausal women with breast cancer treatment-induced bone loss, 24 months of intravenous ZOL treatment significantly increased the lumbar spine BMD and the TBS.

INTRODUCTION

The aim of this study was to compare the effects of 4 mg intravenous zoledronate (ZOL) versus placebo (PLB), every 3 months, on the lumbar spine (LS) bone mineral density (BMD) and the trabecular bone score (TBS) in premenopausal women with breast cancer (BC) treatment-induced bone loss. The TBS is a gray-level texture measurement which is related to the bone microarchitecture and considered to be independent of the BMD.

METHODS

Changes in BMD and TBS were assessed in 70 patients who were recruited in the double-blind, placebo-controlled ProBONE-II trial and randomized to receive either ZOL (n = 34) or PLB (n = 36) for 2 years. The changes were assessed at baseline and at 12 and 24 months after treatment initiation.

RESULTS

Patients receiving ZOL showed a mean increase in LS BMD from the baseline to 12 (2.17%) and 24 months (3.14%) of treatment and a mean increase in the TBS of 2.41 and 0.75%, respectively. Conversely, patients receiving PLB showed a mean decrease in the LS BMD from the baseline to 12 (-5.02%) and 24 (-6.43%) months and a mean decrease of -0.52 and -2.16% in the TBS, respectively. Changes in the BMD and the TBS from the baseline to 12 and 24 months were all significantly different for ZOL compared to PLB (p < 0.005). Furthermore, BMD and TBS showed a moderate correlation ranging from 0.28 (p = 0.087) to 0.47 (p = 0.003).

CONCLUSIONS

In premenopausal women with BC, 24 months of intravenous ZOL treatment significantly increased the LS BMD as well as the TBS.

Utility of the trabecular bone score (TBS) in secondary osteoporosis

Altered bone micro-architecture is an important factor in accounting for fragility fractures. Until recently, it has not been possible to gain information about skeletal microstructure in a way that is clinically feasible. Bone biopsy is essentially a research tool. High-resolution peripheral Quantitative Computed Tomography, while non-invasive, is available only sparsely throughout the world. The trabecular bone score (TBS) is an imaging technology adapted directly from the Dual Energy X-Ray Absorptiometry (DXA) image of the lumbar spine. Thus, it is potentially readily and widely available. In recent years, a large number of studies have demonstrated that TBS is significantly associated with direct measurements of bone micro-architecture, predicts current and future fragility fractures in primary osteoporosis, and may be a useful adjunct to BMD for fracture detection and prediction. In this review, we summarize its potential utility in secondary causes of osteoporosis. In some situations, like glucocorticoid-induced osteoporosis and in diabetes mellitus, the TBS appears to out-perform DXA. It also has apparent value in numerous other disorders associated with diminished bone health, including primary hyperparathyroidism, androgen-deficiency, hormone-receptor positive breast cancer treatment, chronic kidney disease, hemochromatosis, and autoimmune disorders like rheumatoid arthritis. Further research is both needed and warranted to more clearly establish the role of TBS in these and other disorders that adversely affect bone.

Breast cancer and osteoporosis - management of cancer treatment-induced bone loss in postmenopausal women with breast cancer

The incidence of breast cancer (BC) in postmenopausal women is continuously rising. Due to early diagnosis and various treatment designs, the long-term clinical outcome has improved. Frequent settings are chemotherapy as well as endocrine treatment. Both have proven to interfere with bone health resulting in cancer treatment-induced bone loss (CTIBL). Whereas chemotherapy is associated with increased bone resorption, aromatase inhibitor (AI) therapy reduces residual estrogen and is associated with decreased bone mineral density. Independent of the AI administered, the loss of bone mineral density is twice as high compared to healthy postmenopausal women. As a consequence of CTIBL, both chemotherapy and AI treatment can lead to a significantly increased fracture risk. Therefore, several guidelines have emerged for the management of CTIBL in women with BC, including strategies to identify and treat those at high risk for fractures. Further research on tracking guideline adherence examining the feasibility and practicability of guideline implementation to bridge the gap between determined scientific best evidence and applied best practice is needed to adjust these guidelines in the future.

Longitudinal changes of trabecular bone score after estrogen deprivation: effect of menopause and aromatase inhibition

PURPOSE

To examine the effects of the menopausal transition and treatment with aromatase inhibitors (AI) on trabecular bone score (TBS, a newly proposed index of bone architecture derived from DXA vertebral scans) and vertebral bone mineral density (BMD).

METHODS

Retrospective cohort study on 29 women who became postmenopausal during a mean follow-up of 2.9 years (MP group) and 34 women treated with AI during a mean follow-up of 2.1 years (AI group). BMD was measured by DXA and TBS with a specific software.

RESULTS

TBS decreased after menopause, but the change was significantly lower than that of the lumbar BMD (-4.6 vs. -6.8 %; mean difference: 2.2 %; p = 0.016). An even larger difference was observed in the AI group (-2.1 vs. -5.9 %; mean difference: 3.8 %; p = 0.002).

CONCLUSIONS

The decrease of TBS induced by menopause or treatment with AI is significantly lower than that of lumbar BMD.

Trabecular bone score: perspectives of an imaging technology coming of age

The trabecular bone score (TBS) is a new method to describe skeletal microarchitecture from the dual energy X-ray absorptiometry (DXA) image of the lumbar spine. While TBS is not a direct physical measurement of trabecular microarchitecture, it correlates with micro-computed tomography (µCT) measures of bone volume fraction, connectivity density, trabecular number, and trabecular separation, and with vertebral mechanical behavior in ex vivo studies. In human subjects, TBS has been shown to be associated with trabecular microarchitecture and bone strength by high resolution peripheral quantitative computed tomography (HRpQCT). Cross-sectional and prospective studies, involving a large number of subjects, have both shown that TBS is associated with vertebral, femoral neck, and other types of osteoporotic fractures in postmenopausal women. Data in men, while much less extensive, show similar findings. TBS is also associated with fragility fractures in subjects with secondary causes of osteoporosis, and preliminary data suggest that TBS might improve fracture prediction when incorporated in the fracture risk assessment system known as FRAX. In this article, we review recent advances that have helped to establish this new imaging technology.