Progressive decrease in bone density over 10 years of androgen deprivation therapy in patients with prostate cancer

Cancer treatment-induced bone loss

Cancer treatment-induced bone loss (CTBL) is associated with anti-tumor treatments, including endocrine therapies, chemotherapeutic treatments, radiotherapy, glucocorticoids, and tyrosine kinase inhibitors. Osteoporosis, characterized by the loss of bone mass, can increase the risk of fractures, leading to mortality and long-term disability, even after cancer remission. Cancer and osteoporosis have marked clinical and pathogenetic similarities. Both have a multifactorial etiology, affect the geriatric population, and markedly influence quality of life. Lifestyle management, including calcium and vitamin D supplementation, is recommended but the supporting evidence is limited. Oral and injectable bisphosphonates are effective for osteoporosis and malignant bone disease. Bisphosphonates increase bone mineral density (BMD) in patients with CTBL. Denosumab is also used in the management of CTBL; in clinical trials, it improved BMD and reduced the risk of fracture. Currently, there are no bone anabolic therapies for patients with cancer. Appropriate therapies are necessary to maintain optimal bone health, particularly in patients at heightened risk.

Management of cancer treatment-induced bone loss (CTIBL) in patients with breast cancer or prostate cancer

Breast cancer and prostate cancer are sex hormone-dependent cancers, and estrogen or androgen suppression therapy is the standard treatment. Cancer treatment-induced bone loss (CTIBL): bone loss and osteoporosis have become important side effects of these therapies. To summarize the current evidences, (1) Endocrine therapy for breast cancer and prostate cancer is associated with a significant decrease in bone mineral density. (2) Aromatase inhibitors (AI) for breast cancer are associated with a significant increase in fractures, and androgen deprivation therapy (ADT) for prostate cancer is likely to be associated with an increase in fractures. (3) Administration of bisphosphonates and denosumab increases bone mass in patients undergoing endocrine therapy for breast cancer. Administration of bisphosphonates, denosumab, and SERMs increased bone mass in patients undergoing ADT therapy for prostate cancer. (4) Bisphosphonates and denosumab reduce fracture risk in patients on AI for breast cancer, and toremifene and denosumab in patients on ADT for prostate cancer.

[Effect of different schemes of androgen deprivation therapy on bone mass density in prostate cancer patients]

OBJECTIVES

To evaluate the aspects of the basal bone health status in prostate cancer patients. Furthermore, to evaluate in a real-world setting the effect of different schemes (intermittent or continuous) of androgen deprivation therapy (ADT) and the effect of denosumab in bone mass density (BMD).

METHODS

Observational, retrospective study of a cohort of prostate cancer patients in treatment with luteinizing hormone-releasing hormone (LH-RH) agonists, evaluated in the rheumatology department of a tertiary center. Demographics, FRAX score, LH-RH treatment scheme, osteoporosis treatment, laboratory data and BMD were collected. Mixed effect regression models to analyze the interaction between LH-RH treatment scheme, denosumab and BMD evolution were used.

RESULTS

Eighty-three patients (mean age 71±8years) were included. At the basal evaluation, 16% of patients presented densitometric osteoporosis and 27% of patients presented high fracture risk. Eighty percent of patients had inadequate vitaminD levels. VitaminD >30ng/mL was correlated with higher T-scores. There was no association between LH-RH treatment scheme and BMD evolution, however there was a positive association with denosumab.

CONCLUSION

A high proportion of patients presented elevated fracture risk or inadequate vitaminD levels, not previously recognized. Bone health assessment and fracture risk evaluation are convenient in these patients. In a real-world setting, the effect of denosumab in BMD is detected, however the effect of intermittent LH-RH schema treatment is less evident.

Dissecting the effects of androgen deprivation therapy on cadherin switching in advanced prostate cancer: A molecular perspective

Prostate cancer is one of the most often diagnosed malignancies in males and its prevalence is rising in both developed and developing countries. Androgen deprivation therapy has been used as a standard treatment approach for advanced prostate cancer for more than 80 years. The primary aim of androgen deprivation therapy is to decrease circulatory androgen and block androgen signaling. Although a partly remediation is accomplished at the beginning of treatment, some cell populations become refractory to androgen deprivation therapy and continue to metastasize. Recent evidences suggest that androgen deprivation therapy may cause cadherin switching, from E-cadherin to N-cadherin, which is the hallmark of epithelial-mesenchymal transition. Diverse direct and indirect mechanisms are involved in this switching and consequently, the cadherin pool changes from E-cadherin to N-cadherin in the epithelial cells. Since E-cadherin represses invasive and migrative behaviors of the tumor cells, the loss of E-cadherin disrupts epithelial tissue structure leading to the release of tumor cells into surrounding tissues and circulation. In this study, we review the androgen deprivation therapy-dependent cadherin switching in advanced prostate cancer with emphasis on its molecular basis especially the transcriptional factors regulated through TFG-β pathway.

Quo Vadis Advanced Prostate Cancer Therapy? Novel Treatment Perspectives and Possible Future Directions

Prostate cancer is a very common disease, which is, unfortunately, often the cause of many male deaths. This is underlined by the fact that the early stages of prostate cancer are often asymptomatic. Therefore, the disease is usually detected and diagnosed at late advanced or even metastasized stages, which are already difficult to treat. Hence, it is important to pursue research and development not only in terms of novel diagnostic methods but also of therapeutic ones, as well as to increase the effectiveness of the treatment by combinational medicinal approach. Therefore, in this review article, we focus on recent approaches and novel potential tools for the treatment of advanced prostate cancer; these include not only androgen deprivation therapy, antiandrogen therapy, photodynamic therapy, photothermal therapy, immunotherapy, multimodal therapy, but also poly(ADP-ribose) polymerase, Akt and cyclin-dependent kinase inhibitors.

Effect on bone mineral density in surgical versus medical castration for metastatic prostate cancer

OBJECTIVE

This pilot study aimed to objectively assess the osteoporotic effect caused by androgen deprivation therapy (ADT) in patients with prostate cancer and compare this effect in surgical versus medical castration, specifically with luteinizing hormone-releasing hormone (LHRH) antagonists.

MATERIAL AND METHODS

The study included 60 patients with metastatic prostate adenocarcinoma treated with either bilateral orchidectomy (group I) or LHRH antagonist (Degarelix) injection (group II). The patients had a baseline bone mineral density (BMD) assessment before the start of ADT using dual energy X-ray absorptiometry (DEXA) scan and then follow-up assessment after 6 months. BMD was measured at the spine (lumbar vertebrae L2-L4), femur (total), and forearm (one-third radius).

RESULTS

Group I included 33 patients and group II 27 patients. Both the groups showed significant reduction in BMD at the spine and femur after 6 months, whereas the forearm did not show a significant reduction. Spine BMD showed 5.9%±2.6% and 4.7%±2.6% reduction whereas the femur BMD showed 6%±7.4% and 6%±4.7% reduction in the orchiectomy and the Degarelix groups, respectively. There was no statistically significant difference between the groups at the 3 measured sites.

CONCLUSION

Both surgical castration and LHRH antagonists were associated with significant accelerated osteoporotic effect at the spine and femur after 6 months without difference between both the methods. Assessment of osteoporotic risk together with preventive or management measures should be started early during ADT.

Pathophysiology of Bone Loss in Patients with Prostate Cancer Receiving Androgen-Deprivation Therapy and Lifestyle Modifications for the Management of Bone Health: A Comprehensive Review

Androgen-deprivation therapy (ADT) is a systemic therapy administered for the management of advanced prostate cancer (PCa). Although ADT may improve survival, long-term use reduces bone mass density (BMD), posing an increased risk of fracture. Considering the long natural history of PCa, it is essential to preserve bone health and quality-of-life in patients on long-term ADT. As an alternative to pharmacological interventions targeted at preserving BMD, current evidence recommends lifestyle modifications, including individualized exercise and nutritional interventions. Exercise interventions include resistance training, aerobic exercise, and weight-bearing impact exercise, and have shown efficacy in preserving BMD. At the same time, it is important to take into account that PCa is a progressive and debilitating disease in which a substantial proportion of patients on long-term ADT are older individuals who harbor axial bone metastases. Smoking cessation and limited alcohol consumption are commonly recommended lifestyle measures in patients receiving ADT. Contemporary guidelines regarding lifestyle modifications vary by country, organization, and expert opinion. This comprehensive review will provide an evidence-based, updated summary of lifestyle interventions that could be implemented to preserve bone health and maintain quality-of-life throughout the disease course of PCa.

Comparative study of surgical orchidectomy and medical castration in treatment efficacy, adverse effects and cost based on a large prospective metastatic prostate cancer registry

INTRODUCTION

Androgen deprivation therapy (ADT) remains the mainstay of treatment for metastatic prostate cancer (mPCa) but is associated with significant morbidities. Comparisons of medical castration (MC) and surgical orchidectomy (SO) have yielded varied results. We aimed to evaluate the oncological outcomes, adverse effect (AE) profiles and costs of MC and SO in patients with mPCa.

METHODS AND MATERIALS

We reviewed 523 patients who presented with de novo mPCa from a prospectively maintained prostate cancer database over 15 years (2001-2015). All patients received ADT (either MC or SO) within 3 months of diagnosis. The data were analyzed with chi-square, binary and logistics regression models.

RESULTS

One hundred and fifty one (28.9%) patients received SO while 372 (71.1%) patients had MC. The median age of presentation was 73 [67 -79] years old. The median prostate-specific antigen (PSA) was 280ng/ml [82.4-958]. Three hundred and thirty one patients (66.3%) had high volume bone metastasis and 57 patients (10.9%) had visceral metastasis. Clinical demographics and clinicopathological were similar across both groups. Similar oncological outcomes were observed in both groups. The proportion of PSA response (PSA <1ng/ml) was 65.6% for SO and 67.2% for MC (P = 0.212). Both therapies achieve >95% of effective androgen suppression (testosterone <50ng/dL). Time to castrate-resistance was similar (18 vs 16 months, P = 0.097), with comparative overall survival (42 vs. 38.5 months, P = 0.058) and prostate cancer mortality (80.1 vs. 75.9%, P = 0.328). Similarly, no difference was observed for the 4 AE profiles between SO and MC respectively; change in Haemoglobin (-0.75 vs. -1.0g/dL, P = 0.302), newly diagnosed Diabetes mellitus (4.6 vs. 2.9%, P = 0.281), control measured by HbA1c (0.2 vs. 0.25%, P = 0.769), coronary artery disease events (9.9 vs. 12.9%, P = 0.376) and skeletal-related fractures (9.3 vs. 7.3%, P = 0.476). After adjusting for varying governmental subsidies and inflation rates, the median cost of SO was $5275, compared to MC of $9185.80.

CONCLUSION

Both SO and MC have similar oncological outcomes and AE profiles. However, SO remains a much more cost-effective form of ADT for the long-term treatment of mPCa patients.

Osteoporosis screening using computed tomography for men with prostate cancer: results of a prospective study

We performed a prospective study using both FRAX and computed tomography to screen for osteoporosis in men undergoing radiation for prostate cancer. We found that implementing routine computed tomography (CT)-based screening was feasible in the setting of a prospective study, but the yield of osteoporosis identification was low in this population.

PURPOSE

Men with prostate cancer (PCa) are at increased risk of hip fracture for multiple reasons. Estimation of hip fracture risk with the FRAX tool is currently recommended, but FRAX alone may not identify a portion of men with osteoporosis. We hypothesized that adding bone mineral density (BMD) screening using CT to FRAX is feasible and would identify more men with osteoporosis.

METHODS

Men with PCa scheduled to undergo CT simulation for radiation treatment were enrolled in a single-arm prospective study. The mean attenuation of the mid-L5 vertebral body trabecular bone (L5_CT) was calculated on a single slice using the radiation simulation CT scan. The 10-year risk of hip fracture was calculated using the FRAX tool. Dual energy X-ray absorptiometry (DXA) was performed for men whose L5_CT measurement was less than 130 Hounsfield units (HU).

RESULTS

A total of 98 eligible men were enrolled and underwent FRAX and CT screening. The median 10-year risk of hip fracture was 1.1% and exceeded 3% in 16 cases; the median L5_CT was 162.28 HU (range 55.6-526.1 HU). DXA scan was completed in 15 men who had L5_CT < 130 HU but 10-year calculated hip fracture risk < 3%, 1 of whom was found to have osteoporosis (T-score ≤ -2.5).

CONCLUSIONS

Implementing CT-based BMD screening was feasible in the setting of a prospective study for men receiving radiation for PCa, but fewer cases than anticipated of osteoporosis were identified.

Bone Health in Men with Prostate Cancer: Review Article

PURPOSE OF REVIEW

The improvement in prostate cancer survival over time, even in those with advanced disease, has led to an increasing recognition of the impact of prostate cancer and its treatment on bone health. Cancer treatment-induced bone loss (CTIBL) is a well-recognized entity but greater awareness of the risks associated with CTIBL and its treatment is required.

RECENT FINDINGS

The principal culprit in causing CTIBL is hormonal ablation induced by prostate cancer treatment, including several new agents which have been developed in recent years which significantly improve survival, but may cause CTIBL. This review discusses the impact of prostate cancer and its treatment on bone health, including published evidence on the underlying pathophysiology, assessment of bone health, and strategies for prevention and treatment. It is important to recognize the potential cumulative impact of systemic prostate cancer treatments on bone health.

Implications of the Fracture Risk Assessment Algorithm for the assessment and improvement of bone health in patients with prostate cancer: A comprehensive review

OBJECTIVE

Maintaining the optimum bone health is one of the important concerns in patients with prostate cancer, but it usually remains neglected. Failure to screen these patients is detrimental to both the length and the quality of life. The estimation of bone mineral density (BMD) and more recently the World Health Organization's fracture risk assessment (FRAX) algorithm in appropriate patients is recommended by several specialty organizations/associations at the time of instituting androgen deprivation therapy (ADT) for metastatic and high-risk individuals. It provides a 10-year risk evaluation of hip and major osteoporotic fractures (MOF). Using this web-based new investigating tool, candidates at high risk of fractures can be predicted more accurately according to clinical risk factors (CRF) alone or in combination with the femoral neck BMD. The FRAX application for senile osteoporosis has been studied and reviewed extensively, but no systematic review has ever been conducted for assessing the implication of FRAX in prostate cancer. This review article will give insight about the validity, role, and utility of this investigating tool in clinical practice for fracture risk assessment in these individuals.

MATERIAL AND METHODS

This systematic review was carried out as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and Cochrane review principles. We searched the PubMed, Cochrane database of systematic reviews, and the EMBASE electronic database until December 2018 using the medical subject heading terms prostate cancer and FRAX.

RESULTS

A total of nine studies meet the inclusion criteria and were included in the review. These studies enrolled a total of 3704 patients (sample size range, 78-1220) of localized, metastatic, castration resistant prostate cancer with or without ADT and/or on photon or radiotherapy. The factors that influenced FRAX included age, ethnicity, baseline BMD, duration of ADT, presence of CRF, and measurement methods (CRF, with/without BMD, computed tomography based). An advanced age and duration of ADT were the most robust risk factors. A 10-year MOF and hip fracture risk estimation was higher when the femoral neck BMD was not incorporated in the FRAX measurement. Despite several well-known strengths of using FRAX in the fracture risk assessment of suitable candidates with prostate cancer, several risk factors such as the mode/duration of ADT, mode of radiotherapy, Vitamin D levels, bone remodeling markers, and recent/recurrent fractures need to be incorporated in the FRAX calculator for improving the predictive ability. In contrast to senile osteoporosis with a longer life expectancy, the fracture risk in patients with prostate cancer need to be measured more frequently and for a shorter time. Therefore, models like Garvan calculator with both 5- and 10-year risk estimates have to be developed for these patients. Additionally, its utilization is of limited value in the presence of recurrent fractures or falls.

CONCLUSION

The FRAX algorithm is beneficial in identifying patients who require early intervention or bone-directed therapy as an early step to decrease skeletal-related events and other morbidity. Several risk factors need to be added for improving the FRAX predictive value. This model is still underutilized in the clinical practice and increasing the awareness among treating physicians will help in optimizing the bone health and the quality of life of this important population subgroup.

Protocol for a phase III RCT and economic analysis of two exercise delivery methods in men with PC on ADT

BACKGROUND

Androgen deprivation therapy (ADT) is commonly used to treat prostate cancer. However, side effects of ADT often lead to reduced quality of life and physical function. Existing evidence demonstrates that exercise can ameliorate multiple treatment-related side effects for men on ADT, yet adherence rates are often low. The method of exercise delivery (e.g., supervised group in-centre vs. individual home-based) may be important from clinical and economic perspectives; however, few studies have compared different delivery models. Additionally, long-term exercise adherence and an understanding of predictors of adherence are critical to achieving sustained benefits, but such data are lacking. The primary aim of this multi-centre phase III non-inferiority randomized controlled trial is to determine whether a home-based delivery model is non-inferior to a group-based delivery model in terms of benefits in fatigue and fitness in this population. Two other key aims include examining cost-effectiveness and long-term adherence.

METHODS

Men diagnosed with prostate cancer of any stage, starting or continuing on ADT for at least 6 months, fluent in English, and living close to a study centre are eligible. Participants complete five assessments over 12 months (baseline and every 3 months during the 6-month intervention and 6-month follow-up phases), including a fitness assessment and self-report questionnaires. Biological outcomes are collected at baseline, 6, and 12 months. A total of 200 participants will be randomized in a 1:1 fashion to supervised group training or home-based training supported by smartphones, health coaches, and Fitbit technology. Participants are asked to complete 4 to 5 exercise sessions per week, incorporating aerobic, resistance and flexibility training. Outcomes include fatigue, quality of life, fitness measures, body composition, biological outcomes, and program adherence. Cost information will be obtained using patient diary-based self-report and utilities via the EQ-5D.

DISCUSSION

To disseminate publicly funded exercise programs widely, clinical efficacy and cost-effectiveness have to be demonstrated. The goals of this trial are to provide these data along with an increased understanding of adherence to exercise among men with prostate cancer receiving ADT.

TRIAL REGISTRATION

The trial has been registered at clinicaltrials.gov (Registration # NCT02834416 ). Registration date was June 2, 2016.

Androgen-targeted therapy in men with prostate cancer: evolving practice and future considerations

Background

Androgen deprivation therapy (ADT) is foundational in the management of advanced prostate cancer (PCa) and has benefitted from a recent explosion in scientific advances. These include approval of new therapies that suppress testosterone (T) levels or inactivate its function, improvements in diagnostic and assay technologies, identification of lower therapeutic targets for T, discovery of the relevance of germline genetic mutations and identification of the benefits of sequential and combination therapies.

Methods

This review discusses the clinical profiles of the most up-to-date options for ADT, best practices for managing patients with advanced PCa and future directions in therapy.

Results and conclusions

Modern assay technologies reveal that bilateral orchiectomy results in a serum T level of approximately 15 ng/dL as compared to the historical definition of castration of T < 50 ng/dL. Evidence shows that lowering T levels to <20 ng/dL improves patient survival and delays disease progression. Routine monitoring of T in addition to prostate-specific antigen throughout treatment is important to ensure continuing efficacy of T suppression. New drugs that inhibit androgen signaling in combination with traditional ADT suppress T activity to near zero and have significantly improved patient survival. When personalizing ADT regimens physicians should consider a number of factors including initiation and duration of ADT, monitoring of T levels and PSA, the possibility of switching monotherapies if a patient does not achieve adequate T suppression, and consideration of intermittent vs. continuous ADT according to patients’ lifestyles, comorbidities, risk factors and tolerance to treatment.

Effect of Androgen Deprivation Therapy on Bone Mineral Density in a Prostate Cancer Cohort in New Zealand: A Pilot Study

Introduction:

Reduction in bone mineral density (BMD) is a common side effect of androgen deprivation therapy (ADT). We aimed to examine the cross-sectional and longitudinal variation in BMD and associated bone markers in patients with nonmetastatic prostate cancer (PCa) managed with and without ADT.

Methods:

Bone mineral density of the total body, lumbar spine, femoral neck, ultradistal forearm, and one-third distal radius was measured in 88 patients with PCa without bone metastases at baseline and at 6 months. Patients were categorized into 4 groups: (1) acute ADT (≤6 months), (2) chronic ADT (>6 months), (3) former ADT, and (4) no ADT (controls). Serum levels of bone metabolism markers, procollagen type I N-terminal propeptide (PINP) and C-terminal cross-linking telopeptide of type I collagen (CTX), were also measured.

Results:

In the cross-sectional analysis, men receiving chronic ADT had significantly lower total body BMD as compared with former ADT users and men with no ADT. In longitudinal analysis, a significant reduction in ultradistal forearm BMD was observed in both acute and chronic ADT users after 6 months (4.08% and 2.7%, P = .012 and .026, respectively). A significant reduction in total body BMD was observed in acute ADT users (2.99%, P = .032). Former ADT users had a significant increase in both lumbar spine and femoral neck BMD (2.84% and 1.59%, P = .008 and .002, respectively). The changes in BMD were not significantly different between acute and chronic ADT users. In the cross-sectional analysis, higher levels of PINP and CTX were observed in acute and chronic ADT users than former ADT users or PCa controls. In longitudinal analysis, the level of serum PINP and CTX did not change significantly from baseline to 6 months in acute, chronic, and former ADT users, or PCa controls, and the percentage change did not differ among the 4 groups.

Conclusions:

Men on acute ADT had a similar rate of bone loss to men on chronic ADT. Reversibility in ADT-induced bone loss was observed in those who discontinued ADT. Serum levels of PINP and CTX were higher in acute and chronic ADT users and levels returned to the range of PCa controls when treatment was withdrawn.

LHRH analog therapy is associated with worse metabolic side effects than bilateral orchiectomy in prostate cancer

PURPOSE

The morbidity associated with metabolic syndrome induced by androgen deprivation therapy (ADT) in prostate cancer (PCa) has not been widely studied. There are no studies comparing surgical and pharmacological castration with regards to their metabolic side effects. The aim of this study was to compare both modalities.

METHODS

A prospective observational study was conducted in men with PCa and with indications of any ADT. The participants were divided into two groups: (1) bilateral orchiectomy and (2) LHRH analogs. The metabolic profile was assessed before and during the period of ADT. Bioelectrical impedance analysis (BIA) and bone mineral density were measured before and after 6 months of treatment. The data were analyzed using the Chi-squared test, Student's t test, Bonferroni's test, and ANOVA.

RESULTS

We enrolled 102 men for analysis, of whom 46 (54.9 %) had been subjected to bilateral orchiectomy and 56 (54.9 %) had been subjected to treatment with LHRH analogs. The basal metabolic profile, body mass index, and BIA were similar between the two groups. The oncologic control (PSA and testosterone) was also similar in both groups. In the intergroup comparison, insulin resistance (p = 0.044) and hemoglobin (p = 0.001) were worse in the group that used LHRH analogs, which was mainly diabetic patients (p = 0.007).

CONCLUSION

This study showed that LHRH analogs had worse effects relative to insulin resistance, mainly in diabetic patients, and induced more anemia and bone demineralization compared to surgical castration. Further prospective, randomized, and comparative studies are needed for metabolic syndrome in ADT modalities.

Combining Computed Tomography-Based Bone Density Assessment with FRAX Screening in Men with Prostate Cancer

To investigate the addition of a computed tomography (CT)-based method of osteoporosis screening to FRAX without bone mineral density (BMD) fracture risk assessment in men undergoing radiotherapy for prostate cancer, we reviewed the records of all patients with localized prostate cancer treated with external beam radiotherapy at our institution between 2001 and 2012. The 10-yr probability of hip fracture was calculated using the FRAX algorithm without BMD. The CT attenuation of the L5 trabecular bone (L5_CT) was assessed by contouring the trabecular bone on a single CT slice at the level of the midvertebral body and by averaging the Hounsfield units (HU) of all included voxels. L5_CT values of 105 and 130 HU were used as screening thresholds. The clinical characteristics of additional patients identified by each L5_CT screening threshold value were compared to patients whose estimated 10-yr risk of hip fracture was 3% or greater by FRAX without BMD. A total of 609 patients treated between 2001 and 2012 had CT scans available for review and complete clinical information allowing for FRAX without BMD risk calculation. Seventy-four (12.2%) patients had an estimated 10-yr risk of hip fracture of 3% or greater. An additional 22 (3.6%) and 71 (11.6%) patients were identified by CT screening when thresholds L5_CT = 105 HU and L5_CT = 130 HU were used, respectively. Compared to the group of patients identified by FRAX without BMD, the additional patients identified by CT screening at each L5_CT threshold level tended to be younger and heavier, and were more likely to be African-American or treated without androgen deprivation therapy. These results suggest that the addition of CT-based screening to FRAX without BMD risk assessment identifies additional men with different underlying clinical characteristics who may be at risk for osteoporosis and may benefit from pharmacological therapy to increase BMD and reduce fracture risk.

Bone health and its correlates in Korean prostate cancer patients receiving androgen deprivation therapy

PURPOSE

This study aimed to examine bone health status, identify factors associated with bone mineral density (BMD), and determine potential risk factors for osteoporosis in Korean prostate cancer patients receiving androgen deprivation therapy (ADT).

METHODS

Using a cross-sectional descriptive design, we recruited 139 men with prostate cancer receiving ADT at two university-based hospitals in South Korea. Participants completed a self-reported questionnaire and underwent dual energy X-ray absorptiometry testing. BMD (gm/cm(2)), bone health status (normal BMD, osteopenia, and osteoporosis), and lifestyle variables (physical activity, smoking, and alcohol consumption) were measured.

RESULTS

The prevalence in our sample was 49.6% for osteopenia and 17.3% for osteoporosis. In multivariate linear regression analyses, BMD was positively associated with body mass index, number of comorbidities, and level of physical activity and negatively associated with being unemployed or retired, having a lower monthly income, and being treated with gonadotropin-releasing hormone therapy alone. In logistic regression analyses, potential risk factors for osteoporosis were low monthly income (OR = 4.33, p = 0.011), receipt of radiation therapy (OR = 4.69, p = 0.018), and lack of regular physical activity (OR = 2.63, p = 0.035).

CONCLUSIONS

Our results suggest that a proportion of prostate cancer survivors who are receiving ADT warrant monitoring to prevent osteoporosis, particularly men of lower economic status and those having lower levels of physical activity. Nurses can play an important role in screening these high risk groups.

Contemporary hormone therapy with LHRH agonists for prostate cancer: avoiding osteoporosis and fracture

Introduction

Prostate cancer is a large clinical burden across Europe. It is, in fact, the most common cancer in males, accounting for more than 92,300 deaths annually throughout the continent. Prostate cancer is androgen-sensitive; thus an androgen deprivation therapy (ADT) is often used for treatment by reducing androgen to castrate levels. Several ADT agents have achieved benefits with effective palliation, but, unfortunately, severe adverse events are frequent. Contemporary ADT (Luteinising Hormone Releasing Hormone agonist - LHRHa injections) can result in side effects that include osteoporosis and fractures, compromising quality of life and survival.

Methods

In this review we analysed the associated bone toxicity consequent upon contemporary ADT and based on the literature and our own experience we present future perspectives that seek to mitigate this associated toxicity both by development of novel therapies and by better identification and prediction of fracture risk.

Results

Preliminary results indicate that parenteral oestrogen can mitigate associated osteoporotic risk and that CT scans could provide a more accurate indicator of overall bone quality and hence fracture risk.

Conclusions

As healthcare costs increase globally, cheap and effective alternatives that achieve ADT, but mitigate or avoid such bone toxicities, will be needed. More so, innovative techniques to improve both the measurement and the extent of this toxicity, by assessing bone health and prediction of fracture risk, are also required.

Rates of and risk factors for trabecular and cortical BMD loss in middle-aged and elderly African-ancestry men

Low trabecular (Tb) and cortical (Ct) volumetric BMD (vBMD) are related to increased fracture risk, but little is known about the patterns and correlates of Tb and Ct vBMD loss with aging. We examined the rates of change in total, Tb.vBMD, and Ct.vBMD at the radius and tibia, and identified factors associated with vBMD loss among 1569 men of African descent aged 40 years and older. Quantitative computed tomography was used to measure vBMD 6 years apart. The annualized rate of loss in Tb.vBMD was significant at the radius (-0.047%/yr, p = 0.016) but not at the tibia. At the radius, a significant loss of Tb.vBMD was observed in men aged 40 to 49 years that appeared to be attenuated and not statistically significant among older age men. In contrast, the decline in Ct.vBMD was similar at both skeletal sites (-0.254 to -0.264%/yr, p < 0.0001) and was consistent across all age groups. Positive associations were found for vBMD changes with body weight (all but radius Ct.vBMD) and diabetes (Ct.vBMD only), whereas negative associations were found with hypertension (all but radius Tb.vBMD), smoking (Ct.vBMD only), and androgen deprivation therapy (cortical vBMD only). Trabecular and cortical vBMD loss appears to follow different patterns among middle- and older-aged men of African ancestry. Factors associated with the decline in vBMD also varied by compartment and anatomical site. Additional studies are needed to better understand the physiological mechanisms underlying early BMD loss among African-ancestry men.

Utilization of bone densitometry for prediction and administration of bisphosphonates to prevent osteoporosis in patients with prostate cancer without bone metastases receiving antiandrogen therapy

Background

Prostate cancer subjects with prostate-specific antigen (PSA) relapse who are treated with androgen deprivation therapy (ADT) are recommended to have baseline and serial bone densitometry and receive bisphosphonates. The purpose of this community population study was to assess the utilization of bone densitometry and bisphosphonate therapy in men receiving ADT for non-metastatic prostate cancer.

Methods

A cohort study of men aged 65 years or older with non-metastatic incident diagnoses of prostate cancer was obtained from the Surveillance Epidemiology End Results (SEER)-linked Medicare claims between 2004 and 2008. Claims were used to assess prescribed treatment of ADT, bone densitometry, and bisphosphonates.

Results

A total of 30,846 incident prostate cancer cases receiving ADT and aged 65 years or older had no bone metastases; 87.3% (n=26,935) on ADT did not receive either bone densitometry or bisphosphonate therapy. Three percent (n=931) of the cases on ADT received bisphosphonate therapy without ever receiving bone densitometry, 8.8% (n=2,702) of the cases on ADT received bone densitometry without receiving intravenous bisphosphonates, while nearly 1% (0.90%, n=278) of the cases on ADT received both bone densitometry and bisphosphonates. Analysis showed treatment differed by patient characteristics.

Conclusion

Contrary to the recommendations, bone densitometry and bisphosphonate therapy are underutilized in men receiving ADT for non-metastatic prostate cancer.

Comparison of questionnaires used for screening and symptom identification in hypogonadal men

Late-onset hypogonadism (LOH) is typically defined as the cluster of symptoms appearing in aging men and accompanied by a decrease in serum testosterone levels. The identification of a simple screening tool with a high level of sensitivity and specificity to predict LOH has remained a challenge. To identify men with LOH, a variety of self-administered questionnaires have been developed including The Saint Louis University Androgen Deficiency in the Aging Male (ADAM) Questionnaire, The Quantitative ADAM (qADAM) Questionnaire, The Aging Male Symptoms (AMS) rating scale, The Massachusetts Male Aging Study (MMAS) questionnaire and The New England Research Institutes (NERI) hypogonadism questionnaire. The applicability of these questionnaires in the clinical setting is debated because some of the symptoms associated with LOH could be attributed to the natural process of aging and comorbidities. The goal of this review is to compare the utility and the validity of the different LOH questionnaires.

The use of dietary supplements to alleviate androgen deprivation therapy side effects during prostate cancer treatment

Prostate cancer (PCa), the most commonly diagnosed cancer and second leading cause of male cancer death in Western societies, is typically androgen-dependent, a characteristic that underlies the rationale of androgen deprivation therapy (ADT). Approximately 90% of patients initially respond to ADT strategies, however many experience side effects including hot flashes, cardiotoxicity, metabolic and musculoskeletal alterations. This review summarizes pre-clinical and clinical studies investigating the ability of dietary supplements to alleviate adverse effects arising from ADT. In particular, we focus on herbal compounds, phytoestrogens, selenium (Se), fatty acids (FA), calcium, and Vitamins D and E. Indeed, there is some evidence that calcium and Vitamin D can prevent the development of osteoporosis during ADT. On the other hand, caution should be taken with the antioxidants Se and Vitamin E until the basis underlying their respective association with type 2 diabetes mellitus and PCa tumor development has been clarified. However, many other promising supplements have not yet been subjected large-scale clinical trials making it difficult to assess their efficacy. Given the demographic trend of increased PCa diagnoses and dependence on ADT as a major therapeutic strategy, further studies are required to objectively evaluate these supplements as adjuvant for PCa patients receiving ADT.

Geriatric considerations in the treatment of advanced prostate cancer

Prostate cancer is the most common non-cutaneous cancer in US men and mainly affects elderly patients, with most new diagnoses occurring in those over 65. As the geriatric population in the US continues to grow, the incidence of this disease is likewise expected to rise. Many older patients are diagnosed with advanced disease or are treated only when their disease becomes symptomatic or metastatic. The treatment options for advanced prostate cancer have increased dramatically in the last decade. It is important to understand the nuances of caring for an elderly cancer patient in order to optimally treat prostate cancer, such as the importance of using a geriatric assessment to uncover overlooked or under-reported vulnerabilities. In addition, many of the newly approved agents for the treatment of advanced prostate cancer have a unique mechanism of action and toxicities that warrant consideration when choosing therapies for older patients. This review focuses on the importance of a geriatric assessment as well as the considerations of treating elderly patients with the newer agents approved for prostate cancer.

Impact of androgen suppression and zoledronic acid on bone mineral density and fractures in the Trans-Tasman Radiation Oncology Group (TROG) 03.04 Randomised Androgen Deprivation and Radiotherapy (RADAR) randomized controlled trial for locally advanced prostate cancer

OBJECTIVE

To study the influence of adjuvant androgen suppression and bisphosphonates on incident vertebral and non-spinal fracture rates and bone mineral density (BMD) in men with locally advanced prostate cancer.

PATIENTS AND METHODS

Between 2003 and 2007, 1071 men with locally advanced prostate cancer were randomly allocated, using a 2 × 2 trial design, to 6 months i.m. leuprorelin (androgen suppression [AS]) before radiotherapy alone ± 12 months additional leuprorelin ± 18 months zoledronic acid (ZdA), commencing at randomization. The main endpoint was incident thoraco-lumbar vertebral fractures, which were assessed radiographically at randomization and at 3 years, then reassessed by centralized review. Subsidiary endpoints included incident non-spinal fractures, which were documented throughout follow-up, and BMD, which was measured in 222 subjects at baseline, 2 years and 4 years.

RESULTS

Incident vertebral fractures at 3 years were observed in 132 subjects. Their occurrence was not increased by 18 months' AS, nor reduced by ZdA. Incident non-spinal fractures occurred in 72 subjects and were significantly related to AS duration but not to ZdA. Osteopenia and osteoporosis prevalence rates at baseline were 23.4 and 1.4%, respectively, at the hip. Treatment for 6 and 18 months with AS caused significant reductions in hip BMD at 2 and 4 years (P < 0.01) and ZdA prevented these losses at both time points.

CONCLUSION

In an AS-naïve population, 18 months of ZdA treatment prevented the sustained BMD losses caused by 18 months of AS treatment; however, the study power was insufficient to show that AS duration or ZdA influenced vertebral fracture rates.

[Androgenic treatment of male hypogonadism]

The diagnosis of male hypogonadism should be clearly established on a clinical and biological basis before considering the initiation of a substitutive treatment with androgens. A careful evaluation of advantages, constraints and limitations of the treatment should be done previously. The potential advantages of an androgenic substitution include an improvement of the symptoms of hypogonadism and the prevention of its bone and metabolic consequences. Absolute (namely prostatic) or relative contraindications should be detected before starting any substitution. The modalities of treatment will be adapted to both the patient's age and the goals to reach. The different available formulations do not induce a similar pattern of plasma testosterone levels. Patches, gel applications and long-acting intramuscular formulations [injected every 3 months] result in stable plasma levels in the physiologic range. The main limitation to their use is linked to a financial aspect as they are not the object of any refund. A careful survey (on clinical, biological and radiological basis) should be established after starting the substitutive treatment with androgens.

Changes in bone mineral density in men starting androgen deprivation therapy and the protective role of vitamin D

SUMMARY

Androgen deprivation therapy in 80 men was associated with declines in bone mineral density (BMD), which were greatest in the first year, and in the lumbar spine compared to controls. Vitamin D use was associated with improved BMD in the lumbar spine and in the first year.

INTRODUCTION

Decreased BMD is a common side effect of androgen deprivation therapy (ADT), leading to increased risk of fractures. Although loss of BMD appears to be greatest within the first year of starting ADT, there are few long-term studies of change in BMD, and risk factors for bone loss are not well-characterized.

METHODS

Men aged 50+ with nonmetastatic prostate cancer starting continuous ADT were enrolled in a prospective longitudinal study. BMD was determined by dual-energy x-ray absorptiometry at baseline and yearly for 3 years. Matched controls were men with prostate cancer not receiving ADT. Multivariable regression analysis examined predictors of BMD loss.

RESULTS

Eighty ADT users and 80 controls were enrolled (mean age 69 years); 52.5 % had osteopenia and 8.1 % had osteoporosis at baseline. After 1 year, in adjusted models, ADT was associated with significant losses in lumbar spine BMD compared to controls (-2.57 %, p = 0.006), with a trend towards greater declines at the total hip (p = 0.09). BMD changes in years 2 and 3 were much smaller and not statistically different from controls. Use of vitamin D but not calcium was associated with improved BMD in the lumbar spine in year 1 (+6.19 %, p < 0.001) with smaller nonsignificant increases at other sites (+0.86 % femoral neck, +0.86 % total hip, p > 0.10) primarily in the first year.

CONCLUSIONS

Loss of BMD associated with ADT is greatest at the lumbar spine and in the first year. Vitamin D but not calcium may be protective particularly in the first year of ADT use.

Causes, consequences, and treatment of osteoporosis in men

Men undergo gradual bone loss with aging, resulting in fragile bones. It is estimated that one in five men will suffer an osteoporotic fracture during their lifetime. The prognosis for men after a hip fracture is very grim. A major cause is reduction of free testosterone. Many other factors result in secondary osteoporosis, including treatment for other diseases such as cancer and diabetes. Patients should be screened not only for bone density but also assessed for their nutritional status, physical activity, and drug intake. Therapy should be chosen based on the type of osteoporosis. Available therapies include testosterone replacement, bisphosphonates, and nutritional supplementation with calcium, vitamin D, fatty acids, and isoflavones, as well as certain specific antibodies, like denosumab and odanacatib, and inhibitors of certain proteins.

Optimal bone health management strategies in patients with prostate cancer

Bone health is affected in patients with prostate cancer, both by the disease and its treatment. Metastases to bone leads to pain, fractures, and spinal cord compression; bone loss due to androgen deprivation therapy (ADT) leads to osteoporosis and its complications. Both these scenarios are a major cause of morbidity and adversely affect the quality of life of these patients. Maintaining an optimum bone health throughout the natural course of prostate cancer is an important aspect in the management of this disease. An understanding of the complex interplay between osteoclasts, osteoblasts, receptor activator of nuclear factor κB (RANK), and various other tyrosine kinases involved in the pathophysiology of bone metastases is essential. Zoledronic acid (ZA), an intravenously administered bisphosphonate, and Denosumab, a subcutaneously administered inhibitor of nuclear factor B ligand (RANKL), have already been approved by Food and Drug Administration (FDA) for their use in treatment of bone metastases. This article discusses the pathophysiology of bone metastases and bone loss due to ADT in prostate cancer, role of biomarkers, newer modalities of imaging, World Health Organization (WHO)/FRAX nomogram in evaluation of these patients, utility of currently available drugs and evidence supporting their use, and newer therapeutic agents like alpha-emitting Radium-223, endothelin-A receptor antagonists (Atrasentan and Zibotentan) and the proto-oncogene tyrosine-protein kinase (SRC) inhibitor, Dasatinib.

Androgen deprivation therapy impact on quality of life and cardiovascular health, monitoring therapeutic replacement

INTRODUCTION

Androgen deprivation therapy (ADT) is commonly utilized in the management of both localized and advanced adenocarcinoma of the prostate. The use of ADT is associated with several adverse events, physical changes, and development of medical comorbidities/mortality.

AIM

The current article reviews known adverse events associated with ADT as well as treatment options, where available. Current recommendations and guidelines are cited for ongoing monitoring of patients receiving ADT.

METHODS

A PubMed search of topics relating to ADT and adverse outcomes was performed, with select articles highlighted and reviewed based on level of evidence and overall contribution.

MAIN OUTCOME MEASURES

Reported outcomes of studies detailing adverse effects of ADT were reviewed and discussed. Where available, randomized trials and meta-analyses were reported.

RESULTS

ADT may result in several adverse events including decreased libido, erectile dysfunction, vasomotor symptoms, cognitive, psychological and quality of life impairments, weight gain, sarcopenia, increased adiposity, gynecomastia, reduced penile/testicular size, hair changes, periodontal disease, osteoporosis, increased fracture risk, diabetes and insulin resistance, hyperlipidemia, and anemia. The definitive impact of ADT on lipid profiles, cardiovascular morbidity/mortality, and all-cause mortality is currently unknown with available data. Treatment options to reduce ADT-related adverse events include changing to an intermittent treatment schedule, biophysical therapy, counseling, and pharmacotherapy.

CONCLUSIONS

Patients treated with ADT are at increased risk of several adverse events and should be routinely monitored for the development of potentially significant morbidity/mortality. Where appropriate, physicians should reduce known risk factors and counsel patients as to known risks and benefits of therapy.

Optimal management of recurrent prostate cancer in older patients

With a large, aging population in the USA and continued prolongation of life expectancy, treatment of cancer in the elderly will continue to be of importance. The most common cancer in men is prostate cancer, which is most often diagnosed in those over the age of 65 years. Initial therapies for prostate cancer are local treatments in those with localized disease and for whom definitive therapy is appropriate. Optimal treatment of an older patient with recurrent prostate cancer now involves more of a decision process than treatment has in the past, with the recent approval of several new medical agents for advanced prostate cancer. Through this article we will focus on treatment options for recurrent prostate cancer, keeping in mind the unique characteristics of the elderly population. A majority of the discussion will focus on many of the newly approved agents used to treat castration-resistant prostate cancer, and exciting agents currently under investigation. Improved androgen blockade has improved overall survival in patients with metastatic disease but carries many of the same adverse effects as previous agents. Newer approaches with immunotherapy, radiopharmaceuticals, or second-generation androgen receptor blockers introduce a different adverse-effect profile for older patients. As data matures, these too may improve survival for patients with metastatic disease. Throughout all stages of disease, one must keep in mind the unique needs of an older patient population.

A phase 3, double-blind, randomised, parallel-group, placebo-controlled study of oral weekly alendronate for the prevention of androgen deprivation bone loss in nonmetastatic prostate cancer: the Cancer and Osteoporosis Research with Alendronate and Leuprolide (CORAL) study

BACKGROUND

Androgen-deprivation therapy (ADT) induces loss of bone mineral density (BMD) and increases the risk of fractures in patients with prostate cancer (PCa). We sought to determine whether a weekly dose of alendronate, an oral bisphosphonate, could reduce this unwanted side-effect.

OBJECTIVE

To assess whether once-weekly oral alendronate therapy would maintain or improve BMD in men initiating ADT for localised PCa.

DESIGN, SETTING, AND PARTICIPANTS

A multicentre, double-blind, randomised, placebo-controlled study, we included hormonally naïve PCa patients initiating ADT with leuprolide acetate 30 mg intramuscularly every 4 mo.

INTERVENTION

Patients were randomised to receive either oral alendronate 70 mg once weekly or placebo for 1 yr. Both groups received daily calcium 1g and vitamin D 400 international units.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Changes in BMD (at the lumbar spine [LS] and total hip [TH]) and bone markers.

RESULTS AND LIMITATIONS

One hundred ninety-one subjects were enrolled, and 186 were randomised between alendronate (n=84) and placebo (n=102). The alendronate group demonstrated a mean spine BMD increase of 1.7% compared with -1.9% in the placebo group (p<0.0001). Alendronate also increased the BMD at the hip (percent change: 0.7%) compared to placebo (-1.6%). Median urinary N-terminal crosslinking telopeptide of type I collagen (Ntx) values decreased by 3.5% in the alendronate group and increased by 16.5% in the placebo arm, even after adjusting for centre (p=0.510) and baseline urinary Ntx (p<0.0001). Bone-specific alkaline phosphatase (BSAP) decreased a median of 2.25% in the alendronate group and increased a median of 3.12% in the placebo arm, regardless of centre or baseline BSAP or other covariates (p<0.0001). The safety and tolerability profile was similar for the two treatment groups.

CONCLUSIONS

Although the study was closed early because of slow accrual, it showed that weekly oral alendronate prevented bone loss and increased bone mass in addition to decreasing bone turnover in patients initiating ADT for localised PCa, with few related side-effects.

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

Hormone ablation therapy (HALT) for breast or prostate cancer accelerates the development of osteoporosis in both men and women by causing estrogen deficiency, which increases the risk for fracture by promoting bone resorption mediated by osteoclasts. Denosumab, a fully human monoclonal antibody that inhibits osteoclast formation and function, increases bone mass in patients undergoing hormone ablation therapy. In the HALT study of 1,468 men with prostate cancer on androgen-deprivation therapy, denosumab significantly reduced the risk of new vertebral fractures, increased bone mineral density (BMD), and reduced markers of bone turnover. In a study of 252 women with breast cancer undergoing adjuvant aromatase inhibitor (AI) therapy, denosumab increased BMD at 12 and 24 months, overall and in all patient subgroups. The overall rates of adverse events were similar to placebo. Clinicians should consider fracture risk assessment and therapies such as denosumab to increase bone mass in patients on hormone ablation therapy who are at high risk for fracture.

Advanced prostate cancer treated with intermittent or continuous androgen deprivation in the randomised FinnProstate Study VII: quality of life and adverse effects

BACKGROUND

Intermittent dosing may reduce the adverse events (AEs) of androgen-deprivation therapy (ADT).

OBJECTIVE

To compare intermittent androgen deprivation (IAD) and continuous androgen deprivation (CAD) with regard to health-related quality of life (QoL).

DESIGN, SETTING, AND PARTICIPANTS

A total of 852 men with advanced prostate cancer (PCa) were enrolled to receive goserelin acetate 3.6 mg every 28 d for 24 wk. A total of 554 patients whose prostate-specific antigen (PSA) decreased to <10 ng/ml or by ≥50% (<20 ng/ml at baseline) were randomised to IAD or CAD.

INTERVENTION

In the IAD arm, ADT was resumed for at least 24 wk whenever PSA increased >20 ng/ml or above baseline.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

QoL was monitored with a validated Cleary 30-item questionnaire and analysed by the Mann-Whitney U test, 0.5 standard deviation rule, and repeated measures analysis of variance. AEs and adverse drug reactions (ADRs) were analysed by the chi-square test.

RESULTS AND LIMITATIONS

Median follow-up was 65 mo. Significant differences in QoL emerged in activity limitation, physical capacity, and sexual functioning, favouring IAD. No significant differences emerged in the prevalence of AEs: 87 patients in the IAD arm (31.8%) and 95 in the CAD arm (33.9%) had cardiovascular (CV) AEs (p=0.59), with 25 (9.1%) and 29 (10.4%) withdrawn (p=0.62), and 21 (7.7%) and 24 (8.6%) dying because of a CV event (p=0.70), respectively; bone fractures occurred in 19 (6.9%) and 15 (5.4%) patients (p=0.44), respectively. Hot flushes or night sweats were the most common ADRs (47.1% vs 50.4%; p=0.44). Erectile dysfunction (15.7% vs 7.9%; p=0.042) and depressed mood (2.2 vs 0%; p=0.032) were more common in the IAD arm.

CONCLUSIONS

IAD showed benefits in the treatment of advanced PCa with respect to QoL. The prevalence of AEs was not significantly lower with IAD.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00293670.

Androgen deprivation therapy for prostate cancer: implications for cardiometabolic clinical care

Prostate cancer (PCa) is the most common malignancy in men. Androgen deprivation therapy (ADT) plays an important role in the management of locally advanced and metastatic PCa. Its use in combination with external beam radiation and as an adjuvant therapy has resulted in improved survival in a subset of patients with locally advanced disease. In men with metastatic disease, ADT results in improvement in pain and overall quality of life. In addition to these two clinical settings where ADT has proven benefits, it is also being increasingly used in patients experiencing biochemical recurrence and those with early stage localized disease, even though no survival advantage has been demonstrated. ADT has significant adverse effects such as sexual dysfunction, decreased lean mass, increased fat mass, decreased quality of life, anemia, and osteoporosis. Recently, insulin resistance, diabetes, and metabolic syndrome have emerged as complications of ADT. Some data also suggests that ADT might be responsible for incident cardiovascular disease. Since the majority of men with PCa die of conditions other than their malignancy, recognition and management of these adverse effects is important. This paper serves as a focused review of recent studies examining the metabolic abnormalities and cardiovascular disease related to ADT.

Type I Collagen Synthesis Marker Procollagen I N-Terminal Peptide (PINP) in Prostate Cancer Patients Undergoing Intermittent Androgen Suppression

Intermittent androgen suppression (IAS) therapy for prostate cancer patients attempts to maintain the hormone dependence of the tumor cells by cycles alternating between androgen suppression (AS) and treatment cessation till a certain prostate-specific antigen (PSA) threshold is reached. Side effects are expected to be reduced, compared to standard continuous androgen suppression (CAS) therapy. The present study examined the effect of IAS on bone metabolism by determinations of serum procollagen I N-terminal peptide (PINP), a biochemical marker of collagen synthesis. A total of 105 treatment cycles of 58 patients with prostate cancer stages ≥pT2 was studied assessing testosterone, PSA and PINP levels at monthly intervals. During phases of AS lasting for up to nine months PSA levels were reversibly reduced, indicating apoptotic regression of the prostatic tumors. Within the first cycle PINP increased at the end of the AS period and peaked in the treatment cessation phase. During the following two cycles a similar pattern was observed for PINP, except a break in collagen synthesis as indicated by low PINP levels in the first months off treatment. Therefore, measurements of the serum PINP concentration indicated increased bone matrix synthesis in response to >6 months of AS, which uninterruptedly continued into the first treatment cessation phase, with a break into each of the following two pauses. In summary, synthesis of bone matrix collagen increases while degradation decreases during off-treatment phases in patients undergoing IAS. Although a direct relationship between bone matrix turnover and risk of fractures is difficult to establish, IAS for treatment of biochemical progression of prostate tumors is expected to reduce osteoporosis in elderly men often at high risk for bone fractures representing a highly suitable patient population for this kind of therapy.

Aging and osteoporosis in breast and prostate cancer

As people with cancer survive longer, and as the US population ages, skeletal effects of cancer treatment are becoming more pronounced. This is particularly true for breast and prostate cancer survivors because of the high average age of patients with these malignancies, the propensity of older adults in general toward the development of osteoporosis, and the wide use of therapeutic agents in these cancers that negatively impact bone health. Various therapies used in the treatment and prevention of cancer may cause decreases in bone mineral density and an increased risk of debilitating fracture, even in the absence of bone metastases. Aging is both a baseline risk factor in the development of osteoporosis and bony fracture, as well as a predictor of poor outcome after fracture. A variety of mechanisms may be responsible for the development of bone loss in patients with breast or prostate cancer. Cytotoxic chemotherapy may directly exert long-term toxic effects on bone. Chemotherapy and endocrine therapy can induce hypogonadism, leading to an increased rate of bone loss. The risk of skeletal events in older adults due to cancer therapy should be appreciated by all oncologists, geriatricians, and internists. The following review may serve as a guide to the skeletal side effects of cancer therapy in older adults with breast or prostate cancer, how to screen for treatment-related bone loss, and how to best prevent and/or treat skeletal events.

Age-related decline in bone density among ethnically diverse older men

We compared rates of BMD decline in older men of diverse ethnic background. The rate of bone loss was statistically equivalent between men of African and Caucasian descent.

INTRODUCTION

Race differences in peak bone mineral density (BMD) are well established, but the magnitude of bone loss among non-white men has not been well characterized. Our objective was to compare and contrast the rates of decline in BMD with aging among older men of different race/ethnic groups.

METHODS

The rate of decline in hip BMD was measured by dual-energy X-ray absorptiometry (Hologic QDR-4500 W) with an average follow-up of 4.6 years in 3,869 Caucasian, 138 African American, 145 Asian, and 334 Afro-Caribbean men aged ≥ 65 years (Mean ages: 73 ± 5, 70 ± 4, 72 ± 5, 71 ± 5 years, respectively).

RESULTS

The annual rate of decline in BMD at the femoral neck was -0.32%, -0.42%, -0.09%, and -0.44%/year for Caucasian, African American, Asian, and Afro-Caribbean men, respectively (p < 0.05 for Caucasian versus Asian). Although men of African ancestry have higher peak BMD than Caucasians, rates of decline in BMD with aging appear to be statistically equivalent in our study. In contrast, Asian men experienced a slower rate of decline in BMD compared with Caucasians and African Americans.

CONCLUSION

More studies are needed to better define the natural history of and factors associated with bone loss among non-white men.

Intermittent androgen suppression for prostate cancer

Although androgen deprivation therapy (ADT) has been a cornerstone of the management of prostate cancer for more than 50 years, controversy remains regarding its optimum application. Intermittent androgen suppression (IAS) has been researched since the mid-1980s as a way of reducing the adverse effects and cost of continuous androgen suppression. With preclinical evidence suggesting a potential benefit in terms of time to androgen independence, IAS has been the focus of a number of clinical phase II and III trials. Overall, these trials suggest that IAS is neither inferior nor superior to continuous androgen suppression, with respect to time to castration resistance and cancer-specific survival, but has significant advantages in terms of adverse effects, quality of life and cost. A number of unresolved questions remain, however, including how to select patients for therapy, the optimum duration of therapy, when to restart therapy after the off cycle, and how to define progression to castration-resistant disease. Landmark randomized clinical trials comparing IAS to continuous androgen suppression are in progress and will hopefully answer many of these questions. In future, the use of second-line drugs in the off-treatment phase holds potential for delaying disease progression in men on IAS. At present, men with advanced disease who are deemed candidates for ADT should be informed of IAS as a treatment option, considered experimental from an informed consent point of view, but promising based on current evidence.

Emerging drugs for the management of cancer treatment induced bone loss

AREAS COVERED IN THIS REVIEW

We focus our attention on data on the efficacy of currently available and emerging drugs for the management of cancer treatment induced bone loss (CTIBL) found in a PubMed research from 1997 till today.

IMPORTANCE OF THE FIELD

One of the most common and severe safety issues of the antihormonal therapy in both sexes is the CTIBL and the related fragility fractures. In postmenopausal women with estrogenic receptor positive breast cancer, the third-generation aromatase inhibitors (AIs) are the standard therapy. Observational retrospective studies have found that AIs treated patients had a high rate of bone loss and fracture risk (RR 1.3). Also in men with prostate cancer receiving androgen deprivation therapy, the increase in bone turnover and the consequent bone loss are very rapid and sustained significantly increasing the fracture risk.

WHAT THE READER WILL GAIN

The aim of our review is to provide the current evidences for the management of bone loss and fracture risk in this subpopulation.

TAKE HOME MESSAGE

The very high rate of bone loss and the high incidence of fractures indicate that cancer patients at risk of CTIBL need to be carefully monitored and stratified for fracture risk. Although there is a strong evidence of efficacy in prevention of bone loss and reduction of fracture risk for many drugs approved for postmenopausal osteoporosis (PMO) and male osteoporosis, for CTIBL there are actually no drugs approved for this indication.

Effect of zoledronic Acid on bone mineral density in men with prostate cancer receiving gonadotropin-releasing hormone analog

Background. Loss of bone density with androgen deprivation therapy for prostate cancer is well recognized. We assessed the effects of quarterly infusion of zoledronic acid on bone mineral density (BMD) and markers of bone turnover over a one-year period in men receiving gonadotropin-releasing hormone analog (GnRH-a) for prostate cancer. Methods. 41 subjects were randomly assigned to treatment with zoledronic acid (4 mg) IV infusion or placebo every 3 months. The primary endpoint was the change in the lumbar spine BMD after 12 months of treatment. Results. The change in vertebral BMD in the zoledronic acid group (+7.93 ± 1.4%) was significantly (P < .05) greater than the change in the placebo group (+0.82 ± 1.7%) as was the change in left femoral neck BMD (+5.05 ± 1.4% for the zoledronic acid group versus −0.48 ± 1.4% for the placebo group). The decrease in biochemical markers of bone turnover was significantly (P < .05) greater in the zoledronic acid group compared to the placebo group. Conclusion. Quarterly infusion of zoledronic acid for 1 year improved vertebral and left femoral neck BMD with a decrease in bone turnover markers in men on GnRH-a treatment. Zoledronic acid treatment appears to be promising in men with low BMD receiving GnRH-a treatment.

Cost-effectiveness of fracture prevention in men who receive androgen deprivation therapy for localized prostate cancer

BACKGROUND

Androgen deprivation therapy (ADT) increases the risk for fractures in patients with prostate cancer.

OBJECTIVE

To assess the cost-effectiveness of measuring bone mineral density (BMD) before initiating ADT followed by alendronate therapy in men with localized prostate cancer.

DESIGN

Markov state-transition model simulating the progression of prostate cancer and the incidence of hip fracture.

DATA SOURCES

Published literature.

TARGET POPULATION

A hypothetical cohort of men aged 70 years with locally advanced or high-risk localized prostate cancer starting a 2-year course of ADT after radiation therapy.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTION

No BMD test or alendronate therapy, a BMD test followed by selective alendronate therapy for patients with osteoporosis, or universal alendronate therapy without a BMD test.

OUTCOME MEASURES

Incremental cost-effectiveness ratio (ICER), measured by cost per quality-adjusted life-year (QALY) gained.

RESULTS OF BASE-CASE ANALYSIS

The ICERs for the strategy of a BMD test and selective alendronate therapy for patients with osteoporosis and universal alendronate therapy without a BMD test were $66,800 per QALY gained and $178,700 per QALY gained, respectively.

RESULTS OF SENSITIVITY ANALYSES

The ICER for universal alendronate therapy without a BMD test decreased to $100,000 per QALY gained, assuming older age, a history of fractures, lower mean BMD before ADT, or a lower cost of alendronate.

LIMITATIONS

No evidence shows that alendronate reduces actual fracture rates in patients with prostate cancer who receive ADT. The model predicted fracture rates by using data on the surrogate BMD end point.

CONCLUSION

In patients starting adjuvant ADT for locally advanced or high-risk localized prostate cancer, a BMD test followed by selective alendronate for those with osteoporosis is a cost-effective use of resources. Routine use of alendronate without a BMD test is justifiable in patients at higher risk for hip fractures.

Preserving bone health in patients with hormone-sensitive prostate cancer: the role of bisphosphonates

Men with prostate cancer initiating androgen-deprivation therapy (ADT) may have multiple factors that threaten their skeletal health, including increased fracture risk from bone loss during ADT and the propensity to develop bone metastases, which may lead to skeletal-related events (SREs). Bisphosphonates have utility in oncology for patients with bone metastases to prevent bone loss during hormonal therapy and in the benign setting to treat osteoporosis. These agents have an emerging role in patients with hormone-sensitive prostate cancer (HSPC). Etidronate, alendronate, pamidronate, and zoledronic acid have all shown efficacy in preventing ADT-related bone loss. Alendronate and zoledronic acid have also been shown to increase bone mineral density vs baseline during ADT. Patients with bone metastases from HSPC who received 4 mg zoledronic acid every 3 or 4 weeks had a low incidence of skeletal complications, although controlled study data have not been reported. Bisphosphonate treatment in men with HSPC may be effective for the prevention of ADT-related bone loss, underscoring the importance of treating early to avoid SREs and potentially delay disease progression to metastatic bone disease.