Relationship Between Bone Mineral Density and Androgen-deprivation Therapy in Japanese Prostate Cancer Patients

Hormone-Related and Drug-Induced Osteoporosis: A Cellular and Molecular Overview

Osteoporosis resulting from an imbalance of bone turnover between resorption and formation is a critical health issue worldwide. Estrogen deficiency following a nature aging process is the leading cause of hormone-related osteoporosis for postmenopausal women, while glucocorticoid-induced osteoporosis remains the most common in drug-induced osteoporosis. Other medications and medical conditions related to secondary osteoporosis include proton pump inhibitors, hypogonadism, selective serotonin receptor inhibitors, chemotherapies, and medroxyprogesterone acetate. This review is a summary of the cellular and molecular mechanisms of bone turnover, the pathophysiology of osteoporosis, and their treatment. Nuclear factor-κβ ligand (RANKL) appears to be the critical uncoupling factor that enhances osteoclastogenesis. In contrast, osteoprotegerin (OPG) is a RANKL antagonist secreted by osteoblast lineage cells. Estrogen promotes apoptosis of osteoclasts and inhibits osteoclastogenesis by stimulating the production of OPG and reducing osteoclast differentiation after suppression of IL-1 and TNF, and subsequent M-CSF, RANKL, and IL-6 release. It can also activate the Wnt signaling pathway to increase osteogenesis, and upregulate BMP signaling to promote mesenchymal stem cell differentiation from pre-osteoblasts to osteoblasts rather than adipocytes. Estrogen deficiency leads to the uncoupling of bone resorption and formation; therefore, resulting in greater bone loss. Excessive glucocorticoids increase PPAR-2 production, upregulate the expression of Dickkopf-1 (DKK1) in osteoblasts, and inhibit the Wnt signaling pathway, thus decreasing osteoblast differentiation. They promote osteoclast survival by enhancing RANKL expression and inhibiting OPG expression. Appropriate estrogen supplement and avoiding excessive glucocorticoid use are deemed the primary treatment for hormone-related and glucocorticoid-induced osteoporosis. Additionally, current pharmacological treatment includes bisphosphonates, teriparatide (PTH), and RANKL inhibitors (such as denosumab). However, many detailed cellular and molecular mechanisms underlying osteoporosis seem complicated and unexplored and warrant further investigation.

Higher serum alkaline phosphatase value indicates the need for bone mineral density testing in non-metastatic prostate cancer patients undergoing androgen deprivation therapy

PURPOSE

Osteoporosis is a well-known adverse effect of androgen deprivation therapy for prostate cancer. This study aimed to reveal the factors associated with the diagnosis of osteoporosis in prostate cancer patients undergoing androgen deprivation therapy.

METHODS

This retrospective cross-sectional study included 106 prostate cancer patients treated with androgen deprivation therapy. Patients with bone metastasis at the initiation of androgen deprivation therapy and those with castration-resistant prostate cancer were excluded. Bone mineral density was measured at the lumbar spine and femoral neck using dual-energy X-ray absorptiometry. Osteoporosis was defined as bone mineral density equal to or below either -2.5 SD or 70% of the mean in young adults. The association between clinicopathological variables and bone mineral density or diagnosis of osteoporosis was investigated.

RESULTS

Thirty-six (34%) patients were found to have osteoporosis. The incidence of osteoporosis increased in a stepwise manner depending on the duration of androgen deprivation therapy. Multivariate logistic regression analysis identified a longer duration of androgen deprivation therapy (months, odd's ratio = 1.017, P = 0.006), lower body mass index (kg/m2, odd's ratio = 0.801, P = 0.005) and higher serum alkaline phosphatase value (U/l, odd's ratio 1.007, P = 0.014) as the factors independently associated with the diagnosis of osteoporosis. Eleven out of 50 (22%), 14 out of 35 (40%) and 11 out of 20 patients (55%) were osteoporotic in the patients with serum alkaline phosphatase values <238 U/l, 238-322 U/l and >322 U/l, respectively (P = 0.022).

CONCLUSIONS

Osteoporosis is common in prostate cancer patients undergoing androgen deprivation therapy; furthermore, its incidence increases depending on the duration of androgen deprivation therapy. Bone mineral density testing should be considered for all patients on androgen deprivation therapy, especially for those with a lower body mass index and higher serum alkaline phosphatase value.

Bone mineral density, structure, distribution and strength in men with prostate cancer treated with androgen deprivation therapy

Androgen deprivation therapy (ADT) improves survival in men with advanced prostate cancer (PCa), but has been associated with compromised skeletal health and increased fracture risk. However, limited previous research has investigated determinants of bone strength beyond DXA-derived areal bone mineral density (aBMD) in this population group. The aim of this cross-sectional study was to investigate the effects of ADT in men with PCa on BMD, bone structure, estimates of whole bone strength and cortical bone distribution. A total of 70 ADT-treated men, 52 PCa controls and 70 healthy controls had DXA lumbar spine and proximal femur aBMD and pQCT distal (4%) and proximal (66%) tibia and radius cortical and trabecular volumetric BMD (vBMD), bone structure, strength and cortical bone distribution assessed. Analyses included BMI and/or tibia/radius length as covariates. On average, ADT-treated men had a higher BMI than PCa (P < 0.05) but not healthy controls. ADT-treated men had 7.2-7.8% lower lumbar spine aBMD than PCa (P = 0.037) and healthy controls (P = 0.010), with a trend for a lower total hip aBMD in the ADT-treated men (P = 0.07). At the distal tibia, total bone area was 6.2-7.3% greater in ADT-treated men than both controls (P < 0.01), but total vBMD was 8.4-8.7% lower in ADT-treated men than both controls (P < 0.01). Moreover, bone strength index (BSI) was 10.8% lower relative to healthy controls only (P < 0.05). At the distal radius, ADT-treated men had lower total and trabecular vBMD (10.7-14.8%, P < 0.05) and BSI (23.6-27.5%, P < 0.001) compared to both controls. There were no other differences in bone outcomes at the proximal tibia or radius. In conclusion, ADT treatment for PCa was associated with lower BMD and estimated compressive bone strength, particularly at trabecular skeletal sites (lumbar spine, and distal tibia and radius), compared to controls, but there were no consistent differences in cortical bone structure, distribution or bending strength.

Decrease of bone mineral density in Japanese patients with non-metastatic prostate cancer treated with androgen deprivation therapy

The aim of this study was to conduct a cross-sectional survey of investigations related to the bone mineral density (BMD) of both non-metastatic prostate cancer (NMPC) patients who have not yet received androgen deprivation therapy (ADT) and patients receiving prolonged ADT in Japan. Japanese male patients with NMPC who received continuous ADT or who were planning to receive ADT were enrolled in this study. Lumbar spine and femoral neck BMD was measured using dual-energy X-ray absorptiometry (DEXA). To assess patient characteristics, we searched medical records and questionnaires to determine whether they had any factors that could possibly affect BMD. A total of 230 patients with a mean age of 76.6 ± 6.4 years were evaluated. Of these, 151 (65.7%) were receiving ADT, and 79 (34.4%) had not yet received ADT. The mean duration of ADT was 37.4 ± 30.7 months. DEXA showed that as the duration of ADT increased, lumbar spine and femoral neck BMD decreased gradually (p = 0.0005 and p = 0.0014, respectively). Stepwise regression analyses revealed that the duration of ADT was a significant variable of both lumbar spine and femoral neck BMD. Moreover, as the duration of ADT increased, the prevalence of osteoporosis increased statistically (p = 0.0002). This study showed that ADT negatively affected lumbar spine and femoral neck BMD. It also showed a progressive increase in the prevalence of osteoporosis in Japanese NMPC patients with ADT.

Identification of curable high-risk prostate cancer using radical prostatectomy alone: who are the good candidates for undergoing radical prostatectomy among patients with high-risk prostate cancer?

Background

Currently, there is no consensus regarding which patients with high-risk prostate cancer (PCa) would benefit the most by radical prostatectomy (RP). We aimed to identify patients with high-risk PCa who are treatable by RP alone.

Methods

We retrospectively reviewed data on 315 patients with D’Amico high-risk PCa who were treated using RP without neoadjuvant or adjuvant therapy at the institutions of the Yamaguchi Uro-Oncology Group between 2009 and 2013. The primary endpoint was biochemical progression-free survival (bPFS) after RP. Risk factors for biochemical progression were extracted using the Cox proportional hazard model. We stratified the patients with high-risk PCa into 3 subgroups based on bPFS after RP using the risk factors.

Results

At a median follow-up of 49.9 months, biochemical progression was observed in 20.5% of the patients. The 2- and 5-year bPFS after RP were 89.4 and 70.0%, respectively. On multivariate analysis, Gleason score (GS) at biopsy (≥ 8, HR 1.92, p < 0.05) and % positive core (≥ 30%, HR 2.85, p < 0.005) were independent predictors of biochemical progression. Patients were stratified into favorable- (0 risk factor; 117 patients), intermediate- (1 risk factor; 127 patients), and poor- (2 risk factors; 57 patients) risk groups, based on the number of predictive factors. On the Cox proportional hazard model, this risk classification model could significantly predict biochemical progression after RP (favorable-risk, HR 1.0; intermediate-risk, HR 2.26; high-risk, HR 5.03; p < 0.0001).

Conclusion

The risk of biochemical progression of high-risk PCa after RP could be stratified by GS at biopsy (≥ 8) and % positive core (≥ 30%).

Metabolic changes in patients with prostate cancer during androgen deprivation therapy

Androgen deprivation therapy continues to be widely used for the treatment of prostate cancer despite the appearance of new-generation androgen-receptor targeting drugs after 2000. Androgen deprivation therapy can alleviate symptoms in patients with metastatic prostate cancer and might have a survival benefit in some patients, but it causes undesirable changes in lipid, glucose, muscle or bone metabolism. These metabolic changes could lead to new onset or worsening of diseases, such as obesity, metabolic syndrome, diabetes mellitus, cardiovascular disease, sarcopenia or fracture. Several studies examining the influence of androgen deprivation therapy in Japanese patients with prostate cancer also showed that metabolic changes, such as weight gain, dyslipidemia or fat accumulation, can occur as in patients in Western countries. Efforts to decrease these unfavorable changes and events are important. First, overuse of androgen deprivation therapy for localized or elderly prostate cancer patients should be reconsidered. Second, intermittent androgen deprivation therapy might be beneficial for selected patients who suffer from impaired quality of life as a result of continuous androgen deprivation therapy. Third, education and instruction, such as diet or exercise, to decrease metabolic changes before initiating androgen deprivation therapy is important, because metabolic changes are likely to occur in the early androgen deprivation therapy period. Fourth, routine monitoring of weight, laboratory data or bone mineral density during androgen deprivation therapy are required to avoid unfavorable events.

Comparison of bone mineral loss by combined androgen block agonist versus GnRH in patients with prostate cancer: A 12 month-prospective observational study

The multi-centre, prospective, observational study was designed to examine the efficacy of continuous combined androgen block (CAB) vs. GnRH agonist monotherapy in terms of bone mineral density (BMD) change during 12 months post-androgen deprivation therapy (ADT) in Asian prostate cancer patients. Multiple regression analysis and estimated the 10-year probability of major fractures among the patients with Fracture Risk Assessment Tool were conducted to investigate the underlying factors affecting BMD. Paired t-test to evaluate the change of BMD from baseline to 12 month, and two sample t-test to examine the difference of BMD changes were used between two groups. BMD significantly decreased in both the CAB and GnRH groups, with no group wise differences. The proportion of osteopenia or osteoporosis was slightly increased after the 12-month post-ADT. Ten-year probability of hip fracture and major osteoporotic fracture was approximately 3% and 5%, respectively. In conclusion, a significant decrease of BMD by 12-month ADT was observed without any differences between the two groups, whereas ADT-related BMD loss did not induce detrimental effects on bone health in terms of increased bone fracture risk. This was the first prospective study on BMD changes as a predictor of fracture during ADT in an Asian population.

Prostate cancer in East Asia: evolving trend over the last decade

Prostate cancer is now becoming an emerging health priority in East Asia. Most of our current knowledge on Prostate cancer has been generated from studies conducted in Western population; however, there is considerable heterogeneity of Prostate cancer between East and West. In this article, we reviewed epidemiologic trends, risk factors, disease characteristics and management of Prostate cancer in East Asian population over the last decade. Growing evidence from East Asia suggests an important role of genetic and environmental risk factors interactions in the carcinogenesis of Prostate cancer. Exposure to westernized diet and life style and improvement in health care in combination contribute substantially to the increasing epidemic in this region. Diagnostic and treatment guidelines in East Asia are largely based on Western knowledge. Although there is a remarkable improvement in the outcome over the last decade, ample evidence suggests an inneglectable difference in diagnostic accuracy, treatment efficacy and adverse events between different populations. The knowledge from western countries should be calibrated in the Asian setting to provide a better race-based treatment approach. In this review, we intend to reveal the evolving trend of Prostate cancer in the last decade, in order to gain evidence to improve Prostate cancer prevention and control in East Asia.

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.

Androgen deprivation increases the risk of fracture in prostate cancer patients: a population-based study in Chinese patients

Androgen deprivation therapy (ADT) or orchiectomy is associated with an increased risk of osteoporosis or fracture. In this nationwide database analysis, we found that ADT or orchiectomy increased the risk of fracture in Chinese patients with prostate cancer. However, the magnitude of increase is seemingly not as large as that in Western populations.

INTRODUCTION

ADT using gonadotropin-releasing hormone (GnRH) agonists or orchiectomy is associated with an increased risk of osteoporosis or fracture. To investigate the effects of ADT duration or orchiectomy on any type of fracture in Asian patients with prostate cancer, we conducted this retrospective analysis using a nationwide database in Taiwan.

METHODS

We included 17,359 subjects who were newly diagnosed with prostate cancer between January 1, 1998, and December 31, 2007. The risk of first fracture was our primary endpoint.

RESULTS

The rates of fracture from 12 months after prostate cancer diagnosis until the last follow-up date were 8.7 % for all patients, 7.1 % for patients who did not receive ADT or orchiectomy, 9.8 % for patients who received ADT, and 14.4 % for patients who received orchiectomy with or without ADT (P < 0.0001). In a Cox proportional hazard analysis, the relative risk of fracture increased steadily with the number of doses of GnRH agonists received during the first year after cancer diagnosis and with dose density. A significant hazard ratio was observed in patients who received at least nine doses within 1 year after diagnosis and in those whose dose density exceeded two doses per year. Age greater than or equal to 65 years was associated with a significantly lower risk of fracture.

CONCLUSION

ADT or orchiectomy increases the risk of fracture in Chinese patients with prostate cancer. However, the magnitude of this increase is seemingly not as large as that in Western populations.

Androgen deprivation therapy, diabetes and poor physical performance status increase fracture risk in Chinese men treated for prostate cancer

We investigated the fracture risk after androgen deprivation therapy (ADT) for prostate cancer in the Chinese population. All Chinese prostate cancer patients who were treated primarily by radical prostatectomy or radiotherapy, with or without further ADT, from year 2000 to 2009 were reviewed. We compared the fracture risk in patients who were given ADT (ADT group) with those who were not given any ADT (non-ADT group). Potential risk factors including age, diabetes mellitus, hypertension, hyperlipidemia, ischemic heart disease and performance status were reviewed. The fracture risk was analyzed with Kaplan-Meier and multivariate Cox regression analyses. Our cohort consisted of 200 patients in the non-ADT group and 252 patients in the ADT group. The ADT group was shown to have higher fracture risk (p = 0.036) upon Kaplan-Meier analysis. Upon multivariate Cox regression analyses, diabetes mellitus (HR 4.39, 95% CI 1.08-17.83, p = 0.039), poor performance status (HR 3.14, 95% CI 1.24-8.00, p = 0.016) and the use of ADT (HR 4.89, 95% CI 1.03-23.17, p = 0.045) were associated with increased fracture risk. In conclusion, the fracture risk should be considered while deciding on ADT in Chinese men, especially in diabetic patients with poor performance status.

Denosumab: a new option in the treatment of bone metastases from urological cancers

BONE METASTASES OFTEN CREATE SERIOUS CLINICAL PROBLEMS: they lead to poor performance status due to pathologic fractures, spinal cord compression and intractable pain, commonly referred to as skeletal-related events. The receptor activator of nuclear factor-κB (RANK), the RANK ligand (RANKL), and osteoprotegerin, a decoy receptor for RANK, regulate osteoclastogenesis and may play a key role in bone metastasis. Denosumab (XGEVA; Amgen, Thousand Oaks, CA), a fully human monoclonal antibody that binds to and neutralizes RANKL, inhibits osteoclast function, prevents generalized bone resorption and local bone destruction, and has become a therapeutic option for preventing or delaying first on-study skeletal-related events in various malignancies. In the context of urological cancer, three main Phase III clinical studies have been published in prostate cancer. This article provides a brief overview of the characteristics of bone metastasis in urological cancers, reviews the mechanisms of bone metastasis, including the RANK/RANKL/osteoprotegerin axis, the current standard of care, zoledronic acid, and describes the efficacy of the novel bone-targeted agent denosumab in bone metastasis. Denosumab is emerging as a key therapeutic option in the treatment of bone metastases from urological cancers.

Promoting wellness for patients on androgen deprivation therapy: why using numerous drugs for drug side effects should not be first-line treatment

The controversy over androgen deprivation therapy (ADT) for prostate cancer seems to have shifted over the past decade. The issue of adverse events or side effects now seems to dominate over that of clinical efficacy. However, this article provides evidence that questions the treatment of these side effects with numerous prescription medications that have their own unique toxicity profile in patients with nonmetastatic disease. The hope is that patients will no longer be considered passive participants in the prevention and treatment of ADT side effects, now that information is available to help mitigate many of these effects.

Bone mineral density in Jamaican men on androgen deprivation therapy for prostate cancer

Background

Androgen deprivation therapy (ADT) has been reported to reduce the bone mineral density (BMD) in men with prostate cancer (CaP). However, Afro-Caribbeans are under-represented in most studies. The aim was to determine the effect of androgen deprivation therapy (ADT) on the bone mineral density (BMD) of men with prostate cancer in Jamaica.

Methods

The study consisted of 346 Jamaican men, over 40 years of age: 133 ADT treated CaP cases (group 1), 43 hormone-naïve CaP controls (group 2) and 170 hormone naïve controls without CaP (group 3). Exclusion criteria included metastatic disease, bisphosphonate therapy or metabolic disease affecting BMD. BMD was measured with a calcaneal ultrasound and expressed in S.D. units relative to young adult men (T score), according to the World Health Organization definition. Patient weight, height and BMI were assessed.

Results

Mean ± sd, age of patients in group 1 (75± 7.4 yrs) was significantly greater than groups 2 and 3 (67 ± 8.1 yrs; 65±12.0 yrs). There was no significant difference in weight and BMI between the 3 groups. . The types of ADT (% of cases, median duration in months with IQR) included LHRH (Luteinizing hormone releasing hormone) analogues (28.6%, 17.9, IQR 20.4), oestrogens (9.8%, 60.5, IQR 45.6) anti-androgens (11.3%, 3.3, IQR 15.2) and orchiectomy (15.7%, 43.4, IQR 63.9). Unadjusted t score of group 1, mean ± sd, (-1.6± 1.5) was significantly less than group 2 (-0.9±1.1) and group 3 (-0.7±1.4), p <0.001. Ninety three (69.9%), 20 (45%) and 75 (42%) of patients in groups 1, 2 and 3 respectively were classified as either osteopenic or osteoporotic (p<0.001). Adjusting for age, there was a significant difference in t scores between groups 1 and 2 as well as between groups 1 and 3 (p<0.001). Compared with oestrogen therapy and adjusting for duration of therapy, the odds of low bone mineral density (osteopenia or osteoporosis) with LHRH analogue was 4.5 (95%CI, 14.3 to 3.4); with anti-androgens was 5.9 (95%CI, 32.7 to 5); with orchiectomy was 7.3 (95%CI, 30 to 5.8) and multiple drugs was 9.2 ((95%CI, 31 to 7.1).

Conclusions

ADT is associated with lower BMD in Jamaican men on hormonal therapy for prostate cancer.