Skeletal fracture associated with androgen suppression induced osteoporosis: the clinical incidence and risk factors for patients with prostate cancer

Development of Zn-2Cu-xMn/Mg Alloys for Orthopedic Applications: Mechanical Performance to In Vitro Degradation under Different Physiological Environments

Zinc (Zn) and its alloys are considered futuristic biodegradable materials for their acceptable mechanical properties, suitable corrosion rate, and good biocompatibility. In this study, we report newly developed biodegradable Zn-2Cu-xMn/Mg (x = 0, 0.1, and 0.5) alloys, aiming to achieve good mechanical strength with excellent elongation, desirable wear resistance, and suitable corrosion rate. The effect of Mn/Mg addition on the structural, mechanical, wear, and degradation behaviors of the Zn-2Cu-xMn/Mg alloys was thoroughly investigated. Degradation and tribological behaviors of the alloys were explored in the presence of simulated body fluid (SBF), Dulbecco's modified Eagle medium (DMEM), and DMEM with a 10% fetal bovine serum (FBS) solution. Alloy elements and hot rolling improve their mechanical properties significantly due to precipitation hardening, grain refinement, and solid solution strengthening owing to the formation of MnZn13 and Mg2Zn11 phases. Among all the alloys, the Zn-2Cu-0.5Mn alloy achieved the highest ultimate tensile strength (UTS) of ∼405 MPa and yield strength (YS) of ∼293 MPa with an excellent elongation of ∼51%. The corrosion behavior of the alloys as determined by a potentiodynamic polarization study under different solutions follows the sequence Zn-2Cu < Zn-2Cu-0.5Mn < Zn-2Cu-0.1Mn < Zn-2Cu-0.1Mg < Zn-2Cu-0.5Mg. The corrosion rate by immersion testing for 30 and 90 days also follows the same sequence. The corrosion rate in different solutions follows the order SBF > DMEM + 10%FBS > DMEM. The addition of Mn/Mg also improves the wear resistance and slows the wear rate under wet conditions. The bending test results also indicate the highest bending strength of ∼375 MPa for the Zn-2Cu-0.5Mn alloy, among all the alloys. The bending and tensile strengths deteriorate continuously after the immersion for 30 and 90 days in the solution of SBF, DMEM, and DMEM + 10%FBS. Therefore, the Zn-2Cu-xMn/Mg (x = 0.1 and 0.5) alloys can be considered potential biodegradable implant materials.

Cancer Treatment–Induced Bone Loss and Role of Denosumab in Nonmetastatic Prostate Cancer: A Narrative Review

Bone loss is an important complication of prostate cancer and its associated treatments, especially androgen-deprivation therapy (ADT). There is a 5 to 10 times increased loss of bone mineral density (BMD) in men receiving ADT with yearly 4 to 13% BMD loss. The risk of fracture increases yearly by 5 to 8% with ADT. ADT associated bone loss of 10 to 15% of BMD doubles the risk of fractures. Hence, BMD evaluation through dual-energy X-ray absorptiometry and evaluation of individual fracture risk assessed before initiating ADT. The use of vitamin D, calcium, bisphosphonates, and denosumab has shown improved bone health in men with prostate cancer receiving ADT. Denosumab 60 mg is approved to increase bone mass in men at high risk for fractures receiving ADT for nonmetastatic prostate cancer. Denosumab has shown improvement of 5.6% BMD at 2 years in nonmetastatic prostate cancer patients, with significant improvements seen at the total hip, femoral neck, and distal third of the radius. Denosumab has shown a 62% decreased incidence of new vertebral fractures at 36 months. Furthermore, denosumab delays the onset of bone metastases in high-risk nonmetastatic prostate cancer patients. Denosumab can be preferred over other bone modifying agents owing to several advantages, such as subcutaneous administration and no requirement of hospitalization, no dose modifications in renal impairment and less incidence of acute phase anaphylactic reactions. We review the available evidence of denosumab for managing bone loss in nonmetastatic prostate cancer patients. The relevant articles used in this narrative review were obtained through general search on google and PubMed using the key terms “non-metastatic prostate cancer,” “denosumab,” “bone loss,” “bone mineral density,” “fracture,” “CTIBL,” and “chemotherapy induced bone loss.”

Bone Fracture Incidence After Androgen Deprivation Therapy-Investigational Agents: Results From Cancer Therapy Evaluation Program-Sponsored Early Phase Clinical Trials 2006-2013

Introduction: Androgen deprivation therapy (ADT) is a primary treatment option for patients diagnosed with locally advanced-stage or metastatic prostate cancer. Androgen deprivation can be achieved either by radical orchiectomy or by medical castration using a gonadotropin-releasing hormone agonist. ADT has been linked to an initial 12-month loss of bone mineral density, a risk factor for weight-bearing bone fracture, and therefore, a confounding hazard for adverse event when patients are enrolled on early phase trials. To better understand the frequency of ADT-investigational agent-related bone fracture, we conducted a retrospective study of National Cancer Institute Cancer Therapy Evaluation Program (CTEP)-sponsored early phase trials to determine the number of fractures observed among enrolled prostate cancer patients. Patients and Methods: 464 locally advanced-stage or metastatic prostate cancer patients were identified among seven ADT-investigational agent trials conducted between 2006 and 2013. Demographic, co-morbidity, treatment, and adverse event variables were abstracted from CTEP databases and descriptive statistics were used. Results: 464 men had a median age of 64 years, were mostly white (90%), and had a performance status of 0 or 1 (98%). The number of new bone fractures occurring on or after ADT-investigational agent treatment was very low (4.6 per 1000 person-years). The median pretrial prostate specific antigen level was 29 ng/mL and most men (71%) had prostate cancer histopathology Gleason 7 score or higher. In these trials, 43 percent of men had bone only and 35 percent had bone and visceral metastatic disease. The most frequent grade 1 or 2 adverse events were fatigue (36%), hot flashes (27%), and anemia (17%). Grade 3 or higher adverse events were rare, with hypertension (3%) and hyperglycemia (3%) observed. Conclusions: Identifying bone health factors may still be relevant in selected early phase ADT-investigational agent trial patients, emphasizing the need for improved methods for capturing baseline bone health and studying ADT-investigational agent and concurrent medication interactions on bone health.

Molecular mechanisms and clinical management of cancer bone metastasis

As one of the most common metastatic sites of malignancies, bone has a unique microenvironment that allows metastatic tumor cells to grow and flourish. The fenestrated capillaries in the bone, bone matrix, and bone cells, including osteoblasts and osteoclasts, together maintain the homeostasis of the bone microenvironment. In contrast, tumor-derived factors act on bone components, leading to subsequent bone resorption or excessive bone formation. The various pathways involved also provide multiple targets for therapeutic strategies against bone metastases. In this review, we summarize the current understanding of the mechanism of bone metastases. Based on the general process of bone metastases, we specifically highlight the complex crosstalk between tumor cells and the bone microenvironment and the current management of cancer bone metastases.

Risk of fracture incidence in prostate cancer survivors: a nationwide cohort study in South Korea

PURPOSE

We analyzed the risk of fracture in prostate cancer (PC) survivors compared to that in the general population in South Korea and according to the primary treatment.

METHODS

From 2007 to 2013, a total of 41,733 PC survivors newly diagnosed with PC in South Korea were identified and matched to non-cancer controls. Cox proportional hazards regression analysis was performed to determine the relative risk of fracture.

RESULTS

Compared to the matched controls, PC survivors had a higher risk of fracture (adjusted hazard ratio (aHR) 1.39; 95% confidence interval (CI) 1.33-1.45). Compared to the matched controls, the active surveillance/watchful waiting and radiotherapy group showed a similar risk of fracture (aHR 1.08; 95% CI 0.98-1.20, and aHR 1.04; 95% CI 0.63-1.73, respectively). PC survivors who underwent surgery showed a lower risk of fracture (aHR 0.89; 95% CI 0.82-0.96), while those who underwent surgery + androgen deprivation therapy (ADT) (aHR 1.41; 95% CI 1.26-1.57), radiotherapy + ADT (aHR 1.86; 95% CI 1.50-2.32), and only ADT (aHR 1.92; 95% CI 1.82-2.02) showed a higher risk of fracture than the control group.

CONCLUSION

The risk of fracture differed according to the primary treatment method for PC; survivors who underwent surgery had a lower risk of fracture compared to that of the general population. However, PC survivors treated with ADT showed a higher risk of fracture than the other PC treatment groups or the general population. Therefore, more attention and preventive bone care are required for PC survivors who receive ADT.

A biodegradable Zn-1Cu-0.1Ti alloy with antibacterial properties for orthopedic applications

Zinc (Zn) alloys are receiving increasing attention in the field of biodegradable implant materials due to their unique combination of suitable biodegradability and good biological functionalities. However, the currently existing industrial Zn alloys are not necessarily biocompatible, nor sufficiently mechanically strong and wear-resistant. In this study, a Zn-1Cu-0.1Ti alloy is developed with enhanced mechanical strength, corrosion wear property, biocompatibility, and antibacterial ability for biodegradable implant material applications. HR and HR + CR were performed on the as-cast alloy and its microstructure, mechanical properties, frictional and wear behaviors, corrosion resistance, in vitro cytocompatibility, and antibacterial ability were systematically assessed. The microstructures of the Zn-1Cu-0.1Ti alloy after different deformation conditions included a η-Zn phase, a ε-CuZn₅ phase, and an intermetallic phase of TiZn₁₆. The HR+CR sample of Zn-1Cu-0.1Ti exhibited a yield strength of 204.2 MPa, an ultimate tensile strength of 249.9 MPa, and an elongation of 75.2%; significantly higher than those of the HR alloy and the AC alloy. The degradation rate in Hanks' solution was 0.029 mm/y for the AC alloy, 0.032 mm/y for the HR+CR alloy, and 0.034 mm/y for the HR alloy. The HR Zn-1Cu-0.1Ti alloy showed the best wear resistance, followed by the AC alloy and the alloy after HR + CR. The extract of the AC Zn-1Cu-0.1Ti alloy showed over 80% cell viability with MC3T3-E1 pre-osteoblast and MG-63 osteosarcoma cells at a concentration of ≤ 25%. The as-cast Zn-1Cu-0.1Ti alloy showed good blood compatibility and antibacterial ability. STATEMENT OF SIGNIFICANCE: This work repots a Zn-1Cu-0.1Ti alloy with enhanced mechanical strength, corrosion wear property, biocompatibility, and antibacterial ability for biodegradable implant applications. Our findings showed that Zn-1Cu-0.1Ti after hot-rolling plus cold-rolling exhibited a yield strength of 204.2 MPa, an ultimate tensile strength of 249.9 MPa, an elongation of 75.2%, and a degradation rate of 0.032 mm/y in Hanks' Solution. The hot-rolled Zn-1Cu-0.1Ti showed the best wear resistance. The extract of the as-cast alloy at a concentration of ≤ 25% showed over 80% cell viability with MC3T3-E1 and MG-63 cells. The Zn-1Cu-0.1Ti alloy showed good hemocompatibility and antibacterial ability.

Patients with prostate cancer and androgen deprivation therapy have increased risk of fractures-a study from the fractures and fall injuries in the elderly cohort (FRAILCO)

Osteoporosis is a common complication of androgen deprivation therapy (ADT). In this large Swedish cohort study consisting of a total of nearly 180,000 older men, we found that those with prostate cancer and ADT have a significantly increased risk of future osteoporotic fractures.

INTRODUCTION

Androgen deprivation therapy (ADT) in patients with prostate cancer is associated to increased risk of fractures. In this study, we investigated the relationship between ADT in patients with prostate cancer and the risk of incident fractures and non-skeletal fall injuries both compared to those without ADT and compared to patients without prostate cancer.

METHODS

We included 179,744 men (79.1 ± 7.9 years (mean ± SD)) from the Swedish registry to which national directories were linked in order to study associations regarding fractures, fall injuries, morbidity, mortality and medications. We identified 159,662 men without prostate cancer, 6954 with prostate cancer and current ADT and 13,128 men with prostate cancer without ADT. During a follow-up of approximately 270,300 patient-years, we identified 10,916 incident fractures including 4860 hip fractures.

RESULTS

In multivariable Cox regression analyses and compared to men without prostate cancer, those with prostate cancer and ADT had increased risk of any fracture (HR 95% CI 1.40 (1.28-1.53)), hip fracture (1.38 (1.20-1.58)) and MOF (1.44 (1.28-1.61)) but not of non-skeletal fall injury (1.01 (0.90-1.13)). Patients with prostate cancer without ADT did not have increased risk of any fracture (0.97 (0.90-1.05)), hip fracture (0.95 (0.84-1.07)), MOF (1.01 (0.92-1.12)) and had decreased risk of non-skeletal fall injury (0.84 (0.77-0.92)).

CONCLUSIONS

Patients with prostate cancer and ADT is a fragile patient group with substantially increased risk of osteoporotic fractures both compared to patients without prostate cancer and compared to those with prostate cancer without ADT. We believe that this must be taken in consideration in all patients with prostate cancer already at the initiation of ADT.

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.

Role of BMI and age in predicting pathologic vertebral fractures in newly diagnosed multiple myeloma patients: A retrospective cohort study

Vertebral fractures affect approximately 30% of myeloma patients and lead to a poor impact on survival and life quality. In general, age and body mass index (BMI) are reported to have an important role in vertebral fractures. However, the triangle relationship among age, BMI, and vertebral fractures is still unclear in newly diagnosed multiple myeloma (NDMM) patients. This study recruited consecutive 394 patients with NDMM at Taipei Veterans General Hospital between January 1, 2005 and December 31, 2015. Risk factors for vertebral fractures in NDMM patients were collected and analyzed. The survival curves were demonstrated using Kaplan-Meier estimate. In total, 301 (76.4%) NDMM patients were enrolled in the cohort. In the median follow-up period of 18.0 months, the median survival duration in those with vertebral fractures ≥ 2 was shorter than those with vertebral fracture < 2 (59.3 vs 28.6 months; P = 0.017). In multivariate Poisson regression, BMI < 18.5 kg/m² declared increased vertebral fractures compared with BMI ≥ 24.0 kg/m² (adjusted RR, 2.79; 95% CI, 1.44-5.43). In multivariable logistic regression, BMI < 18.5 kg/m² was an independent risk factor for vertebral fractures ≥ 2 compared with BMI ≥ 24.0 kg/m² (adjusted OR, 6.05; 95% CI, 2.43-15.08). Among age stratifications, patients with both old age and low BMI were at a greater risk suffering from increased vertebral fractures, especially in patients > 75 years and BMI < 18.5 kg/m² (adjusted RR, 12.22; 95% CI, 3.02-49.40). This is the first study that demonstrated that age had a significant impact on vertebral fractures in NDMM patients with low BMI. Elder patients with low BMI should consider to routinely receive spinal radiographic examinations and regular follow-up.

Can androgen-deprivation therapy obviate the need of channel transurethral resection of the prostate in advanced prostate cancer with urinary retention? A prospective study

Objective

To evaluate the efficacy of androgen-deprivation therapy (ADT) in relieving urinary retention in patients with advanced prostate cancer presenting with urinary retention or a high post-void residual urine volume (PVR).

Patients and methods

Patients with advanced prostate cancer with an indwelling catheter for acute/chronic urinary retention, or with a high PVR (>200 mL) who had not received any previous treatment were included in the study. Patients with localised prostate cancer eligible for receiving any therapy aimed at cure were excluded. All enrolled patients were managed by ADT (LHRH antagonist/agonist or orchidectomy) combined with α-adrenoceptor antagonist/combined therapy for at least 1 month to a maximum of 3 months; they were given their first trial of voiding without catheter after 1 month, and monthly thereafter.

Results

A total of 101 patients received ADT of which 97 were able to void successfully at the end of 3 months. In all, 27 patients could void in the first month, followed by 50 in the second month, and an additional 20 in the third month. There was a significant decrease in prostate volume, PVR, and International Prostate Symptom Score, and maximum urinary flow rates improved with normalisation of renal functions and resolution of upper tract changes noted on ultrasonography.

Conclusion

ADT can relieve retention and decrease PVR over a period of time obviating the need for channel transurethral resection of the prostate.

Denosumab is really effective in the treatment of osteoporosis secondary to hypogonadism in prostate carcinoma patients? A prospective randomized multicenter international study

INTRODUCTION

Osteoporosis is a complication of androgen deprivation therapy (ADT) in men with prostate carcinoma. The best defense against osteoporosis in prostate cancer is to identify patients with a high risk for fracture during the first clinical visit, select an effective anti-osteoporosis agent, and advise the patient to change his lifestyle and diet to prevent further bone loss. New agents include denosumab, a human monoclonal antibody that inhibits the RANK ligand (RANKL). RANKL promotes the formation, activity, and survival of osteoclasts and, thus, supports the breakdown of bone.

PURPOSE

This is a multicenter, randomized, double-blind prospective study on use of denosumab versus alendronate in the therapy of secondary osteoporosis related to ADT in prostate cancer patients in three European countries (Italy, France, Switzerland).

PATIENTS AND METHODS

In this 24-month observation study we enrolled 234 patients with diagnosis of osteoporosis underwent ADT for prostate cancer. All patients aged ≥55 years and had a dual-energy X-ray absorptiometry (DEXA) T-score <-1.0 (hip or spine, measured within last 2 years) and ≥ 1 fragility fracture. Patients were randomly assigned 1:1 to receive denosumab 60 mg subcutaneously every 6 months or alendronate (70 mg weekly) for 2 years. All patient received supplemental vitamin D (600 IU per day) and supplemental calcium to maintain a calcium intake of 1200 mg per day. Effectiveness of therapy in both groups (denosumab group and alendronate group) was assessed by changes in bone turnover markers (BTMs), Bone Mineral Density (BMD), fracture incidence, Visual Analogue Scale (VAS) score for back pain, and Short Form-8 (SF-8TM) health survey score for health-related quality of life (HRQoL). Percent changes from baseline in BTMs and BMD were assessed using the paired t test; a P-value 0.05). Mean changes in BMD at final follow-up differed significantly between two groups. BMD changes at the lumbar spine at 24 months were 5.6% with denosumab vs -1.1% with alendronate (P<0.001). New vertebral fractures developed in fewer patients in the denosumab group than in the alendronate group during the 24-month period, although this difference was not significant (P=0.10). Back pain significantly (P<0.001) improved from baseline at all time points during the study in both study groups. SF-8 health survey scores significantly improved following treatment with both drugs. Incidence of adverse drug reactions were similar in both groups.

CONCLUSION

In our study denosumab and alendronate showed similar clinical efficacy in the therapy of ADT-related osteoporosis in men with prostate carcinoma; both drugs provided significant improvements in back pain and general health conditions. Denosumab showed significant increase of BTMs and BMD than alendronate with lower rate of new vertebral fractures.

Androgen Deprivation in Veterans with Prostate Cancer: Implications for Skeletal Health

Background:

Common risk factors for osteoporosis in older men include smoking, heavy use of alcohol, propensity to falls, and use of bone-toxic medications such as prednisone. There is also increasing appreciation of the skeletal risk faced by men receiving androgen deprivation therapy (ADT) for prostate cancer. Measures to prevent bone loss in such patients are available.

Objective:

To test the following hypotheses in a population of veterans receiving ADT for prostate cancer: (1) fracture risk factors in addition to androgen deprivation would be found in most patients, (2) bone mass measurements would be assessed in a minority of patients, and (3) a minority of the subjects would receive bisphosphonate therapy or have contraindications for such treatment.

Methods:

We conducted a retrospective chart review of male veterans receiving ADT from 1993 through 2001, at the Veterans Affairs Medical Center, Madison, WI.

Results:

One hundred and seventy-four subjects met study criteria, with a mean age of 76 years and median duration of 21 months of ADT. Eighty-one percent had risk factors in addition to ADT. Only 13% underwent bone density measurement by dual energy X-ray absorptiometry (DXA) and, of those measured, more than half had osteoporosis. Only 19% of the men received both calcium and vitamin D supplements. Antiresorptive therapy was provided to 11% of men, although more than two-thirds had no contraindications to therapy. A total of 24 men sustained a fracture after starting ADT. For men who did undergo bone density measurement, 77% received antiresorptive therapy. Of those who exhibited osteoporosis by DXA scan, 85% received antiresorptive therapy.

Conclusions:

Male veterans receiving ADT for prostate cancer received inadequate evaluation and treatment for osteoporosis. Based on our data, a simple and practical strategy to prompt further evaluation and improved care may be to undertake bone density measurements in men prior to or soon after commencing ADT.

Importance of bone assessment and prevention of osteoporotic fracture in patients with prostate cancer in the gonadotropic hormone analogues use

The antiandrogenic therapy (ADT) for prostate cancer represents an additional risk factor for the development of osteoporosis and fragility fractures. Still, bone health of patients on ADT is often not evaluated. After literature research we found that simple preventive measures can prevent bone loss in these patients, resulting in more cost-effective solutions to the public health system and family when compared to the treatment of fractures.

Bone mass behavior after 1 year of different treatment strategies in prostate cancer patients subjected to androgen deprivation therapy

The aim of this study was to evaluate bone mass changes after 1 year of four different types of pharmacological intervention. Ninety-seven prostate cancer patients treated with androgen deprivation therapy, and severe osteopenia or osteoporosis were retrospectively studied. Patients were divided in four groups. Group 1: 28 patients treated with denosumab, Group 2: 24 patients treated with alendronate, Group 3: 24 patients with no antiresorptive treatment and Group 4: 21 patients previously treated with alendronate and switched to denosumab. Dual X-ray absorptiometry was performed at baseline and after 1 year. Bone mass changes at the L2-L4 lumbar spine, femoral neck and total hip were evaluated. No differences were found at baseline. After 1 year, men receiving denosumab or alendronate (Group 1 and 2) showed a significant bone mass increase at the lumbar spine (+2.4 and +5.0 %, respectively), while no significant changes were observed in Group 3 and 4. At the femoral neck, Group 1 and 2 patients showed a significant bone mass increase (+3.7 and +3.6 %, respectively), while no significant changes were observed in Group 3 and 4. At the total hip, we observed a significant bone mass increase in Group 1 (+2.9 %) and a significant bone mass loss in Group 3 patients (-1.9 %). No significant changes were observed in Group 2 and 4. Denosumab increased significantly bone mass in all three dual X-ray absorptiometry standard sites, while alendronate did not at total hip. No benefit was observed in men previously treated with alendronate who switched to denosumab treatment.

Osteoblasts stimulate the osteogenic and metastatic progression of castration-resistant prostate cancer in a novel model for in vitro and in vivo studies

Castration-resistant prostate cancer (CRPC) is strongly associated with sclerotic bone metastases and poor prognosis. Models that mimic human CRPC are needed to identify the mechanisms for prostate cancer (PC) growth in bone and to develop new therapeutic strategies. We characterize a new model, LNCaP-19, and investigate the interaction between tumor cells and osteoblasts in the sclerotic tumor response of CRPC. Osteogenic profiling of PC cell lines (LNCaP-19, LNCaP, C4-2B₄, and PC-3) was performed by gene expression arrays and mineral staining. Conditioned medium from MC3T3-E1 was used for osteoblast stimulation of CRPC cells. The capacity of LNCaP-19 cells to induce sclerotic lesions was assessed in intratibial xenografts and verified by serum markers, histological analysis and bone mineral density (BMD) measurements. The CRPC cell line LNCaP-19 expresses a pronounced osteogenic profile compared to its parental androgen-dependent cell line LNCaP. Osteoblast-derived factors further increase the expression of genes known to enhance metastatic progression of PC. LNCaP-19 forms sclerotic tumors in tibia of castrated mice as evident by increased total BMD (P < 0.01). There was a strong correlation between serum osteocalcin and BMD (total: R² 0.811, P < 0.01, trabecular: R² 0.673, P < 0.05). For the first time we demonstrate that a CRPC cell line generated in vitro has osteogenic capacity and that osteomimicry can be an inherent feature of these cells. Osteoblast-derived factors further promote the osteogenic and metastatic phenotype in CRPC cells. Altogether, our model demonstrates that both tumor cells and osteoblasts are mediators of the bone forming process of CRPC.

Adverse effects of androgen deprivation therapy for prostate cancer: prevention and management

The prostate is an androgen-dependent organ. The increase, growth, homeostasis, and function of the prostate largely depend upon the intraprostatic and serum concentrations of androgens. Therefore, androgens are essential for the physiologic growth of prostatic epithelium. Prostate cancer, the second leading cause of death for men, is also androgen dependent, and androgen suppression is the mainstay of treatment for advanced and metastatic disease. In the state of metastatic disease, androgen suppression is a palliative treatment leading to a median progression-free survival of 18–20 months and an overall survival of 24–36 months. Theoretically, the majority of patients will develop hormone-refractory disease provided that they will not die from other causes. Although androgen suppression therapy may be associated with significant and sometimes durable responses, it is not considered a cure, and its potential efficacy is further limited by an array of significant and bothersome adverse effects caused by the suppression of androgens. These effects have potentially significant consequences on a variety of parameters of everyday living and may further decrease health-related quality of life. This review focuses on the aetiology of these adverse effects and provides information on their prevention and management.

[Androgen deprivation therapy for prostate cancer and osteoporotic risk]

Androgen deprivation therapy represents an important part of the management of prostate cancer. However, epidemiological data have shown that it is a well-established cause of osteoporosis and increased risk of fracture. So far no consensus guidelines have been published regarding the screening and treatment of osteoporosis in men with prostate cancer. Here we report the design of a new questionnaire, derived from the FRAX(®) ("Fracture Risk Assessment Tool") algorithm, to evaluate the risk of fracture in those patients. In accordance with recent reviews and on the basis of their experience, our French board of experts recommends systematic screening for osteoporosis with dual energy x- ray absorptiometry scans, practice of exercise and calcium and vitamin D supplementation, and selective treatment with bisphosphonates in men at greatest osteoporotic risk.

Bone densitometric assessment and management of fracture risk in Indian men of prostate cancer on androgen deprivation therapy: Does practice pattern match the guidelines?

Objective:

Estimation of baseline bone mineral density (BMD) at the time of instituting androgen deprivation therapy (ADT) for metastatic prostate cancer is recommended by several specialty groups and expert panels. The present study was carried out to analyze the practice pattern of Indian urologists with regard to bone densitometric assessment and management of fracture risk in men of prostate cancer on ADT, and their degree of adherence to currently available guidelines

Materials and Methods:

Telephonic interviews of 108 qualified urologists, randomly selected from the member database of Urological Society of India was carried out with a predefined questionnaire. The responses were analyzed and compared with the available evidences and recommendations.

Results:

Only 19.4% urologists routinely perform a baseline BMD before starting ADT. Although majority of them prescribe calcium and vitamin D supplementation, only few tell regarding fracture risk and life-style modification to their patients. While 59.6% of the respondents use Zoledronic acid (ZA) in their patients on ADT, half of them prescribe it without knowing the BMD status, which may lead to overuse of ZA.

Conclusion:

Majority of the urologists in India do not follow the guidelines for BMD measurement in prostate cancer. A baseline BMD may help in reducing the unnecessary use of ZA.

Prostate cancer and osteoporosis

Adenocarcinoma of the prostate is one of the commonest cancers in the world. Due to a combination of earlier detection and better treatments, survival has increased dramatically. Prostate cancer itself is associated with lower bone density and increased fractures. This is compounded by the use of androgen deprivation therapy, which causes dramatic falls in circulating testosterone and estrogen, resulting in rapid falls in bone density, decreased muscle mass, and increased fracture rates. Bisphosphonates have been demonstrated to prevent and reverse this bone loss, but there are no anti-fracture data. Denosumab, a monoclonal antibody to RANKL, has recently been shown to increase bone density and reduce fracture rates. Prostate cancer also commonly metastasizes to bone where it can cause complications such as fracture and pain. Both zoledronic acid and denosumab have been demonstrated to reduce skeletal related events. Comparative studies would suggest that densosumab may have an advantage over zoledronic acid.

Vertebral fractures and trabecular microstructure in men with prostate cancer on androgen deprivation therapy

Androgen deprivation therapy (ADT), a treatment for prostate cancer, is associated with bone loss and fractures. Dual-energy X-ray absorptiometry (DXA)-measured bone mineral density does not assess vertebral fractures (VF). High-resolution micro-magnetic resonance imaging (HR-MRI) assesses bone microarchitecture and provides structural information. To determine if VF identification increased the diagnosis of osteoporosis beyond DXA and if HR-MRI demonstrated skeletal deterioration in men with VF, we cross-sectionally studied 137 men aged ≥ 60 years with nonmetastatic prostate cancer on ADT for ≥ 6 months. Vertebral fracture assessment (VFA) by DXA was confirmed with X-rays. HR-MRI of the wrist included bone volume to total volume (BV/TV), surface density (trabecular plates), surface/curve ratio (plates/rods), and erosion index (higher depicts deterioration). VF were found in 37% of men; the majority were unknown. Seven percent of participants were classified as osteoporotic by hip or spine DXA. Thirty-seven percent of men without osteoporosis by DXA had VF identified, suggesting that 90% of patients with clinical osteoporosis would have been misclassified by DXA alone. By ANOVA comparison across VF grades, the BV/TV, surface density, and spine, hip, and wrist DXA were lower, and erosion index was higher in men with moderate-severe VF compared with lesser grades (all p < 0.05). By unadjusted ROC analysis, the addition of HR-MRI to DXA at the spine, hip, and femoral neck added substantially (AUC increased 0.831 to 0.902, p < 0.05) to prediction of moderate-severe vertebral fracture. HR-MRI indices were associated with spine, hip, and wrist DXA measures (p < 0.01). Longer duration of ADT was associated with lower BV/TV, surface density, and surface/curve ratio (p < 0.05). ADT for men with prostate cancer is associated with silent VF. DXA alone leads to misclassifications of osteoporosis, which can be avoided by VF assessment. HR-MRI provides a novel technique to assess deterioration of structural integrity in men with VF and adds micro-structural information.

The side effects of hormonal therapy at the patients with prostate cancer

Prostate cancer is one of most frequent malignant tumours at men. The androgen-deprivation therapy is the part of cancer treatment. It could be used both in the early stage of prostate cancer and in the bone metastates. From this reason the antiandrogen drugs waste systematically grows. Unfortunately androgen-deprivation therapy has numerous side effects such as: the inferior quality of live, sexual disturbances, the fatigue, the anaemia, the bone mineral density loss and the increase of the risk of breaks the bone, the increase of body mass, insulinresistance, hypercholesterolemia, the increase risk of cardiac disorders. The aim of this article is the introduction of the reader with possibly complications androgen-deprivation therapy and with possibilities in diagnosis and treatment.

Comparison of Tamoxifen and Testosterone Propionate in Male Rats: Differential Prevention of Orchidectomy Effects on Sex Organs, Bone Mass, Growth, and the Growth Hormone-IGF-I Axis

Testis dysfunction can weaken bone and reduce muscle mass as well as impair sexual function. Testosterone (T) therapy has useful effects on sex organs, bone, and muscle in T-deficient males, but prostate concerns can preclude T use in some men. Although estrogens or other drugs can protect bone in men, gynecomastia makes estrogens unappealing, and other drugs may also be undesirable in some cases. Selective estrogen receptor modulators (SERMs) inhibit estrogen-evoked sex organ growth but mimic estrogen effects on bone and cholesterol and are advantageous for some women. SERMs may also be useful in men who must avoid androgens. As a preclinical test of this idea, tamoxifen (a SERM) and testosterone propionate (TP, a classic androgen) were compared for their efficacy in preventing varied effects of orchidectomy (ORX) in adult male rats. ORX led to ventral prostate and seminal vesicle atrophy and decreases in somatic growth, proximal tibia bone mineral density (BMD), and serum growth hormone (GH) and insulin-like growth factor I (IGF-I). ORX also increased anterior pituitary glandular kallikrein, serum cholesterol, and body temperature. Pituitary prolactin (PRL) content was unaltered. ORX effects on sex organs, somatic growth, IGF-I, cholesterol, body temperature, and pituitary kallikrein were prevented by TP at 1 mg/kg (3 doses per week), but BMD and GH were unresponsive. ORX effects on BMD and GH were prevented by TP at 10 mg/kg, but this dose evoked supraphysiologic increases in sex organs and PRL, failed to restore somatic growth, and further reduced IGF-I. Tamoxifen (1 mg/kg daily) prevented ORX effects on BMD, GH, and cholesterol without altering basal or TP-induced sex organ growth and further reduced IGF-I and somatic growth. Tamoxifen did not alter basal PRL but blocked increases caused by TP at 10 mg/kg. In summary, tamoxifen prevented ORX effects on bone and cholesterol in male rats without affecting sex organs or PRL and might be useful for men who must avoid androgens. Unexpectedly, a TP dose that replicated testis effects on sex organs and other targets had no effect on BMD or GH, and a larger TP dose that restored BMD and GH was worse at replicating normal male physiology. In addition, correlation/regression results suggested that the GH-IGF-I axis contributes to changes in BMD.

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.

AST-induced bone loss in men with prostate cancer: exercise as a potential countermeasure

Androgen suppression treatment (AST) for men with prostate cancer is associated with a number of treatment-related side effects including an accelerated rate of bone loss. This loss of bone is greatest within the first year of AST and increases the risk for fracture. Pharmaceutical treatment in the form of bisphosphonates is currently used to counter the effects of hormone suppression on bone but is costly and associated with potential adverse effects. Recently, exercise has been shown to be an important adjuvant therapy to manage a range of treatment-related toxicities and enhance aspects of quality of life for men receiving AST. We propose that physical exercise may also have an important role in not only attenuating the bone loss associated with AST but in improving bone health and reducing fracture risk. In this review, the rationale underlying exercise as a countermeasure to AST-induced bone loss is provided.

[Use of zoledronic acid in patients with prostate cancer bone metastases: control of pain and musculoskeletal complications]

Background. Patients suffering from prostatic carcinoma are at high risk of having bone complications because of the metastatic progression of the disease to the skeleton and the consequences of androgenic deprivation. Zoledronic acid is a potent inhibitor of the bone resorption mediated by the osteoclasts, and is the only bisphosphonate whose capacity of reducing significantly the skeleton morbidity in patients with bone metastases is statistically proved. Methods. To attest tolerability and efficacy of zoledronic acid in preventing unfavorable skeletal events and in reducing osteomuscular pain, 25 patients - aged 75 years, suffering from hormone-responsive prostatic carcinoma under hormonal therapy with bone metastases, have been followed and subjected to IV monthly infusion of 4 mg zoledronic acid for 12 consecutive months, associated to daily intake of calcium and multivitamin supplementations. Results. At the end of the study, a sensible improvement in their clinical conditions and in their perception of the pain has been recorded in 23 patients and valued through a set of questions (Brief Pain Inventory). Conclusions. Zoledronic acid is therefore confirmed to be an effective medicine in preventing the skeleton complications and in controlling the painful symptoms in patients suffering from prostatic carcinoma with bone metastases.

Risk stratification in the hormonal treatment of patients with prostate cancer

Prostate cancer (PCa) is the most common type of cancer found in American men, other than skin cancer. The American Cancer Society estimates that there will be 186,320 new cases of prostate cancer in the United States in 2008. About 28,660 men will die of this disease this year and PCa remains the second-leading cause of cancer death in men. One in six men will get PCa during his lifetime and one in 35 will die of the disease. Today, more than 2 million men in the United States who have had PCa are still alive. The death rate for PCa continues to decline, chiefly due to early detection and treatment, and improved salvage therapy such as hormone therapy (HT). HT continues to be a mainstay for primary-recurrent PCa and locally-advanced PCa. However, HT is associated with many undesirable side effects including sexual dysfunction, osteoporosis and hot flashes, all of which can lead to decreased quality of life (QOL). These risks are seen in both long- and short-term HT regimens. Additionally, research in recent years has revealed trends related to clinico pathological variables and their predictive ability in HT outcomes. Awareness of the potential adverse effects, the risks associated with HT and the prognostic ability of clinical and pathological variables is important in determining optimal therapy for individual patients. A rigorous evaluation of the current scientific literature associated with HT was conducted with the goal of identifying the most favorable balance of benefits and risks associated with HT.

Prevention and treatment of side-effects of systemic treatment: bone loss

Cancer treatment-induced bone loss (CTIBL) is generally more rapid and severe than bone loss associated with menopause in women or ageing in men and women. In premenopausal women with breast cancer, CTIBL is mainly caused by chemotherapy with resultant ovarian failure, by GnRH agonists or by tamoxifen. In postmenopausal women, steroidal and non-steroidal aromatase inhibitors (AIs) increase bone turnover, decrease bone mass and increase fracture rate (hazard ratio increased to 1.38-1.55 compared with tamoxifen). Zoledronic acid can prevent bone loss in premenopausal women receiving adjuvant therapy with goserelin in combination with either anastrozole or tamoxifen and in postmenopausal women receiving AIs. Denosumab has been shown in a placebo-controlled study to significantly increase bone mineral density in postmenopausal women under AIs. More limited studies indicate that oral bisphosphonates used at licensed doses for the treatment of postmenopausal osteoporosis can also prevent AI-induced bone loss. In prostate cancer, bone loss that occurs with androgen deprivation therapy (ADT) also leads to an increased fracture rate. The bisphosphonates pamidronate and alendronate can prevent bone loss whereas zoledronic acid can increase bone mass under ADT. As for breast cancer, delay in bisphosphonate therapy is detrimental to bone health. The protective effects of denosumab on bone loss and incidental vertebral fractures have been demonstrated in a 3-year placebo-controlled trial.

Fracture risk in men with prostate cancer: a population-based study

Fractures are increased among men with prostate cancer, especially those on androgen-deprivation therapy (ADT), but few data are available on men with localized prostate cancer. The purpose of this investigation was to estimate fracture risk among unselected community men with prostate cancer and systematically assess associations with ADT and other risk factors for fracture. In a population-based retrospective cohort study, 742 Olmsted County, MN, men with prostate cancer first diagnosed in 1990-1999 (mean age 68.2 ± 8.9 years) were followed for 6821 person-years. We estimated cumulative fracture incidence, assessed relative risk by standardized incidence ratios, and evaluated risk factors in time-to-fracture regression models. All together, 482 fractures were observed in 258 men (71 per 1000 person-years). Overall fracture risk was elevated 1.9-fold, with an absolute increase in risk of 9%. Relative to rates among community men generally, fracture risk was increased even among men not on ADT but was elevated a further 1.7-fold among ADT-treated compared with untreated men with prostate cancer. The increased risk following various forms of ADT was accounted for mainly by associations with pathologic fractures (14% of all fractures). Among men not on ADT (62% of the cohort), more traditional osteoporosis risk factors were implicated. In both groups, underlying clinical characteristics prompting different treatments (indication bias) may have been partially responsible for the associations seen with specific therapies. To the extent that advanced-stage disease and pathologic fractures account for the excess risk, the effectiveness of fracture prevention among men with prostate cancer may be limited.

Androgen deprivation therapy in prostate cancer: anticipated side-effects and their management

PURPOSE OF REVIEW

In men with metastatic or recurrent prostate cancer, androgen deprivation therapy (ADT) is the standard of care. Although effective in cancer control, ADT is associated with multiple adverse effects of which physicians and patients should be aware herein we review these side-effects and their potential management.

RECENT FINDINGS

ADT reduces serum levels of testosterone and estrogen, resulting in changes in body composition, increased fracture risk, development of insulin resistance, and an unfavorable lipid profile. A number of studies have investigated the association of ADT with cardiovascular mortality; however, it is unclear whether such an association exists. Recently, two separate clinical trials have found that denosumab, a monoclonal antibody, and toremifene citrate, a selective estrogen receptor modulator, could be used to reduce the incidence of fracture in men on ADT.

SUMMARY

By providing clinicians with a greater awareness of the literature on ADT, we may minimize the physical and psychological impact of its side-effects. Physicians should be aware of a recent statement by a multilateral advisory panel, stating that there is no indication for a cardiovascular evaluation before starting ADT. Finally, physicians should be informed of recent developments in the prevention of vertebral fractures in men on ADT.

The efficacy of calcitriol therapy in the management of bone loss and fractures: a qualitative review

Osteoporosis, a skeletal disorder characterized by a reduction in bone strength, increases fracture risk. Primary osteoporosis is usually a result of reduced bone mineral density as a consequence of natural aging. Secondary osteoporosis is usually a result of a disease, such as cystic fibrosis, or medical treatment, such as corticosteroids or cancer treatment.

INTRODUCTION

Currently, ten million Americans are osteoporotic and an additional 34 million have the precursor condition, osteopenia. Osteoporosis leads to 1.5 million fractures and 500,000 hospitalizations annually. Osteoporosis-related fractures increase mortality and reduce quality of life. Calcitriol, the active form of vitamin D, regulates intestinal calcium absorption, among other actions. During the past four decades, many clinical trials investigating the effect of calcitriol on bone loss have been performed.

METHODS

We conducted a systematic qualitative review of clinical trials that assessed calcitriol for the treatment of osteoporosis and bone loss. In these clinical trials, calcitriol was used as a monotherapy and in combination with other therapeutic bone agents.

RESULTS AND CONCLUSION

Studies using calcitriol monotherapy, although not conclusive, found that calcitriol slowed the rate of bone loss in a variety of populations. Calcitriol in combination with other therapeutic bone agents was shown to have additional bone-preserving effects when compared to the use of therapeutic bone agents alone. A common side-effect of calcitriol therapy was hypercalcemia and hypercalciuria, but the degree of hypercalcemia was mild. Recent research found that intermittent dosing can reduce hypercalcemia rates. Calcitriol, alone or in combination with other agents, should be considered for the therapy of osteoporosis.

The use of zoledronic acid in men receiving androgen deprivation therapy for prostate cancer with severe osteopenia or osteoporosis

OBJECTIVES

To study the effect of zoledronic acid on patients with pre-existing osteoporosis on androgen deprivation therapy (ADT), who are at highest risk for fracture. Zoledronic acid is a potent bisphosphonate that can prevent osteoporosis in patients with nonmetastatic (M0), prostate cancer (CaP) who are initiating ADT. The effect of zoledronic acid on patients with pre-existing osteoporosis on ADT, who are highest risk for fracture, has not been adequately studied.

METHODS

We enrolled 28 patients with M0 CaP on ADT with severe osteopenia or osteoporosis (baseline bone-mineral density (BMD) T score < -2.0) in this open-label, single-arm trial to assess the effect of zoledronic acid on BMD. All patients also received supplemental calcium and vitamin D, and were counseled about lifestyle modifications. Patients received zoledronic acid (4 mg) intravenously every 3 months for 4 treatments. BMD was measured by dual energy X-ray absorptiometry scan at enrollment, 6 and 12 months. Primary endpoint was percent change in lumbar spine BMD.

RESULTS

This was a high-risk patient population-primarily older Caucasians (mean age, 73 years), former smokers, and moderate users of alcohol. Mean duration of ADT was 2.4 years. Pre-existing osteopenia or osteoporosis was observed in a single site in 9 patients and multiple sites in 19 (68%). After 12 months of zoledronic acid, lumbar spine BMD increased 4.17% (P < .0001), and BMD increased significantly (P < .05) in both hips and the right femoral neck. Seven patients (25%) experienced improved BMD into the nonosteoporotic range (T score > -2.0). Zoledronic acid infusion was well tolerated and without substantial renal toxicity.

CONCLUSIONS

Zoledronic acid improves BMD in men with M0 CaP on ADT with severe osteopenia or osteoporosis (T scores < 2.0). This novel finding identifies a high-risk patient population that can potentially benefit from bisphosphonate therapy.

Anti-Androgen Therapy Suspension following Prolonged Clinical and Biochemical Response: Outcomes in a Series of Elderly Patients with Advanced Prostate Cancer

Aims and background

To describe the outcomes following the suspension of androgen-suppression therapy in a series of elderly patients in an advanced stage of prostate cancer and in prolonged clinical and biochemical response.

Material and methods

Of 371 consecutive patients with advanced prostate cancer and treated with androgen-suppression therapy, 44 older patients were defined as in stable response on the basis of the following: absence of noteworthy dysuria, normal prostate findings on digital rectal examination, and prostate-specific antigen values lower than 0.50 ng/ml. After suspending treatment, it was to be re-scheduled in case of onset of dysuria, evidence of a palpable lesion on digital rectal examination, or a rise in prostate-specific antigen above 10 ng/ml. Progression of disease was defined as a prostate-specific antigen level increase at two subsequent measurements, and/or the appearance of new lesions, and/or evidence of progression of disease on digital rectal examination.

Results and conclusions

Median age of patients was 78.5 years at the moment of therapy suspension. After a median follow-up of 93.9 months, fourteen patients (31.8%) showed progression of disease, but only 7 (15.9%) of these died. In 7 (15.9%) patients, serum testosterone levels did not exceed 0.5 ng/ml, indicating an absence of gonadal activity. The median time to progression was 138.2 months, and the median cumulative survival from the start and from the suspension of androgen-suppression therapy was 105.5 months and 64.1 months, respectively. The savings in drug costs amounted to 772,267 Euro. Taking into consideration these outcomes of survival and of savings in drug costs, we can conclude that in these selected elderly patients, this treatment option could be of interest.

Risk factors for bone loss with prostate cancer in Korean men not receiving androgen deprivation therapy

PURPOSE

Preexisting bone loss in men with prostate cancer is an important issue due to the accelerated bone loss during androgen deprivation therapy (ADT). In addition, a high prostate-specific antigen (PSA) level has been reported to be related to bone metabolism. This study assessed the factors associated with osteoporosis in Korean men with non-metastatic prostate cancer before undergoing ADT.

MATERIALS AND METHODS

The study enrolled patients admitted for a prostate biopsy because of a high PSA or palpable nodule on a digital rectal examination. We divided the patients (n = 172) according to the results of the biopsy: group I, non-metastatic prostate cancer (n = 42) and group II, benign prostatic hypertrophy (BPH; n = 130). The lumbar bone mineral density (BMD) was evaluated using quantitative computed tomography. The demographic, health status, lifestyle, body mass index (BMI), serum testosterone concentration, and disease variables in prostate cancer (Gleason score, clinical stage, and PSA) were analyzed prospectively to determine their effect on the BMD.

RESULTS

The estimated mean T-score was higher in group I than in group II (-1.96 +/- 3.35 vs. -2.66 +/- 3.20), but without statistic significance (p = 0.235). The significant factors correlated with BMD in group I were a high serum PSA (Beta = -0.346, p = 0.010) and low BMI (Beta = 0.345, p = 0.014) in the multiple linear regression model. Also old age (r = -0.481, p = 0.001), a high serum PSA (r = -0.571, p < 0.001), low BMI (r = 0.598, p < 0.001), and a high Gleason's score (r = -0.319, p = 0.040) were the factors related to BMD in the correlation. The significant factors correlated with BMD in group II were old age (Beta = -0.324, p = 0.001) and BMI (Beta = 0.143, p = 0.014) in the multiple linear regression model.

CONCLUSIONS

The risk factors for osteoporosis in men with prostate cancer include a low BMI, and elevated serum PSA. Monitoring BMD from the outset of ADT is a logical first step in the clinical strategy to avoid or minimize potential bone-related complications in these patients.

Cost effectiveness of risk-prediction tools in selecting patients for immediate post-prostatectomy treatment

BACKGROUND AND OBJECTIVE

Ideally, tests that predict the risk of cancer recurrence should be capable of guiding treatment decisions that are both therapeutically effective and cost effective. This paper evaluates the cost effectiveness of two tools that identify patients at high risk for biochemical (prostate-specific antigen) recurrence of prostate cancer after prostatectomy, the hypothesis being that accurate classification of high-risk patients will allow more appropriate use of secondary (adjuvant/salvage) treatment and may improve on current clinical practice. These risk-prediction tools are the Kattan postoperative nomogram, which uses clinicopathologic features, and the Prostate Px test, which employs additional morphometric and immunofluorescence features of the prostate specimen to predict risk of biochemical recurrence. These tools were trained on patients treated at the Memorial Sloan-Kettering Cancer Center (996 patients for the nomogram, 342 patients for the Prostate Px test).

METHODS

The cost effectiveness of the Prostate Px test, the Kattan postoperative nomogram, and current clinical practice were compared using a decision analytic model. The modeled treatment for low-risk patients was watchful waiting. The modeled treatments for high-risk patients were local radiation, hormonal therapy, and watchful waiting. Costs, utilities, and transition probabilities were obtained from the literature. Costs and effects were discounted at 3% per year. The time span modeled was 10 years after prostatectomy. Monte Carlo simulation was performed to estimate cost and effectiveness; sensitivity analysis was performed to examine the impact of uncertainty in the parameter values.

RESULTS

The expected quality-adjusted life years (QALYs) for the Prostate Px test, nomogram, and current practice were 8.11, 7.39, and 6.47, respectively. The expected costs were $US17 549, $US14 162, and $US14 104, respectively. The incremental cost-effectiveness ratio of the Prostate Px was $US4704/QALY compared with the nomogram, and $US2100/QALY compared with current practice. The incremental cost-effectiveness ratio of the nomogram was $US63/QALY compared with current practice. These ratios are well below the common willingness-to-pay limit of $US50 000/QALY. Expected effectiveness was highest for the Prostate Px test, followed by the nomogram. Expected cost was slightly higher for Prostate Px than for either alternative; nevertheless, the Prostate Px was cost effective compared with both the nomogram and current practice. The nomogram was cost effective compared with current practice. The acceptable cost effectiveness of the Prostate Px test and the nomogram compared with current practice were not sensitive to changes in the values used to inform the model within clinically plausible ranges. The superior performance of both Prostate Px test and nomogram over current practice resulted from identifying high-risk patients likely to benefit from adjuvant treatment, while sparing the low-risk patients the added cost and toxicity of treatment.

CONCLUSION

Incorporation of risk-prediction tools in the initial management of patients after prostatectomy resulted in increased QALYs at an acceptable increase in cost relative to current practice.

Implementation of osteoporosis screening guidelines in prostate cancer patients on androgen ablation

Androgen ablation (AA) therapy is one of the modalities used to treat prostate cancer. It is well known that AA therapy increases the risk of osteoporosis and fractures. In 2004, the British Columbia Cancer Agency published guidelines regarding bone health in these patients. A key recommendation was to arrange for bone mineral density (BMD) testing if AA was to be used for 6 mo or longer. Our objective was to evaluate how well these guidelines were implemented by reviewing the number of BMDs performed in patients who had been treated at one of the 4 cancer centers in British Columbia. We found that the overall number of BMDs documented after the implementation of the guidelines was significantly greater than the number documented before (25% vs 7.5%, p value < 0.0001). There appeared to be regional differences in implementation, with the greatest effect seen at the Vancouver center, which serves as the chief academic center for the province. The greater effect of guidelines at this center suggests a need for more effective dissemination peripherally. The care gap remaining at even the most impacted center indicates a need for greater efforts to both implement guidelines and monitor their implementation over time.

Cancer treatment-induced bone loss in breast and prostate cancer

PURPOSE

Bone loss resulting from the treatment of breast and prostate cancer is an emerging problem. Bisphosphonates have a potential role in the prevention of this cancer treatment-induced bone loss (CTIBL).

METHODS

Studies evaluating the incidence and prevalence of CTIBL in early breast and prostate cancer patients and trials evaluating the preventative role of bisphosphonates were identified by a search of the PubMed and Cochrane Library databases through the end of March 2008. Reference lists from retrieved articles were cross referenced, and further information was obtained from relevant scientific meetings.

RESULTS

Several therapies commonly used in the treatment of women and men with breast and prostate cancers, in particular the aromatase inhibitors (AIs) for breast cancer and androgen deprivation therapy (ADT) for prostate cancer, are associated with significant bone loss and with an increase in fracture risk. The use of bisphosphonates seems to attenuate the bone loss, although the long-term impact remains unclear because of insufficient follow-up.

CONCLUSION

Adjuvant endocrine therapy with an AI or androgen deprivation can be considered a risk factor for the development of osteopenia, osteoporosis, and bone fracture, which can be mitigated by appropriate bisphosphonate therapy. Clear identification of risk factors for osteoporosis in individual patients should aid treatment decisions about whether to use bisphosphonates when starting or switching to an AI or ADT. Patients need to be educated about this risk and other measures to avoid this complication, including lifestyle modifications that may benefit their general and bone health.

Androgen deprivation therapy for the treatment of prostate cancer: consider both benefits and risks

CONTEXT

Androgen deprivation therapy (ADT) is increasingly used for the treatment of prostate cancer (PCa), even in clinical settings in which there is no evidence-based proof of prolonged overall survival (OS). ADT, however, may be associated with numerous side effects, including an increased therapy-related cardiovascular mortality.

OBJECTIVE

To discuss different clinical settings in which ADT is currently used and to critically weigh the benefits of ADT against its possible side effects.

EVIDENCE ACQUISITION

A MEDLINE search was conducted to identify original articles and review articles addressing the efficacy and side effects of ADT for the treatment of PCa. Keywords consisted of prostate cancer, hormonal therapy, adverse effects, radical prostatectomy, and radiotherapy. The articles with the highest level of evidence for the various examined end points were identified with the consensus of all authors and were reviewed.

EVIDENCE SYNTHESIS

Even short-term use of ADT may lead to numerous side effects, such as osteoporosis, obesity, sarcopenia, lipid alterations, insulin resistance, and increased risk for diabetes and cardiovascular morbidity. Despite these side effects, ADT is commonly used in various clinical settings in which a clear effect on improved OS has not been shown.

CONCLUSIONS

ADT is associated with an increased risk of multiple side effects that may reduce quality of life and/or OS. Consequently, these issues should be discussed in detail with patients and their families before initiation of ADT. ADT should be used with knowledge of its potential long-term side effects and with possible lifestyle interventions, especially in settings with the highest risk-benefit ratio, to alleviate comorbidities.

Skeletal health after continuation, withdrawal, or delay of alendronate in men with prostate cancer undergoing androgen-deprivation therapy

PURPOSE

Androgen-deprivation therapy (ADT) for prostate cancer is associated with bone loss and osteoporotic fractures. Our objective was to examine changes in bone density and turnover with sustained, discontinued, or delayed oral bisphosphonate therapy in men receiving ADT.

PATIENTS AND METHODS

A total of 112 men with nonmetastatic prostate cancer receiving ADT were randomly assigned to alendronate 70 mg once weekly or placebo in a double-blind, partial-crossover trial with a second random assignment at year 2 for those who initially received active therapy. Outcomes included bone mineral density and bone turnover markers.

RESULTS

Men initially randomly assigned to alendronate and randomly reassigned at year 2 to continue had additional bone density gains at the spine (mean, 2.3% +/- 0.7) and hip (mean, 1.3% +/- 0.5%; both P < .01); those randomly assigned to placebo in year 2 maintained density at the spine and hip but lost (mean, -1.9% +/- 0.6%; P < .01) at the forearm. Patients randomly assigned to begin alendronate in year 2 experienced improvements in bone mass at the spine and hip, but experienced less of an increase compared with those who initiated alendronate at baseline. Men receiving alendronate for 2 years experienced a mean 6.7% (+/- 1.2%) increase at the spine and a 3.2% (+/- 1.5%) at the hip (both P < .05). Bone turnover remained suppressed.

CONCLUSION

Among men with nonmetastatic prostate cancer receiving ADT, once-weekly alendronate improves bone density and decreases turnover. A second year of alendronate provides additional skeletal benefit, whereas discontinuation results in bone loss and increased bone turnover. Delay in bisphosphonate therapy appears detrimental to bone health.

Incidence and risk factors for low trauma fractures in men with prostate cancer

BACKGROUND

Men with prostate cancer on androgen deprivation therapy (ADT) are at increased risk of bone loss. The present study sought to determine the incidence of low trauma fracture in men with prostate cancer (PC), and to characterize the association between potential risk factors and fracture risk in these men.

METHODS

In the prospective, population-based Dubbo Osteoporosis Epidemiology Study, 43 men aged 60+ years reported a history of prostate cancer; among whom, 22 men received ADT, and 21 men did not. Low-trauma fractures were ascertained between 1989 and 2004. Bone mineral density at the femoral neck (FNBMD), postural instability and lifestyle factors were obtained at baseline.

RESULTS

Men with prostate cancer had significantly higher lumbar spine BMD than those without cancer (p=0.013). During the follow-up period, 15 men with prostate cancer had sustained a fracture, yielding the age-adjusted incidence of fracture among this group was 31.6 per 1000 person-years, which was greater than those without cancer (22.1 per 1000 person-years). The age-adjusted incidence of fracture was more pronounced among those with prostate cancer on ADT (40.2 per 1000 person-years). After adjusting for age, the increase in fracture risk among prostate cancer patients was associated with lower femoral neck BMD (hazard ratio [HR] per SD=1.8, 95% CI: 1.0-3.4) and increased rate of bone loss (HR 2.3, 1.2-4.6).

CONCLUSIONS

Men with prostate cancer, particularly those treated with ADT, had an increased fracture risk. Although the average BMD in men with prostate cancer was higher than men without cancer, a low BMD prior to treatment or increased rate of bone loss after initiating ADT treatment was each a significant predictor of fracture in these.