Risk of clinical fractures after gonadotropin-releasing hormone agonist therapy for prostate cancer

Responder analysis of the effects of denosumab on bone mineral density in men receiving androgen deprivation therapy for prostate cancer

BACKGROUND

Denosumab, a fully human monoclonal antibody against RANK ligand, increased bone mineral density (BMD) and reduced fracture risk vs placebo in a phase 3 trial in men with prostate cancer on androgen deprivation therapy (ADT). The present analysis of this study evaluated BMD changes after 36 months in responder subgroups and in individual patients for three key skeletal sites (lumbar spine (LS), femoral neck (FN) and total hip (TH)) and the distal radius.

METHODS

Men with nonmetastatic prostate cancer receiving ADT were treated with subcutaneous denosumab 60 mg (n=734) or placebo (n=734) every 6 months for up to 36 months in a phase 3, randomized, double-blind study. Patients were instructed to take supplemental calcium and vitamin D. For this BMD responder analysis, the primary outcome measure was the percentage change in BMD from baseline to month 36 at the LS, FN and TH as measured by dual-energy X-ray absorptiometry. BMD at the distal 1/3 radius at 36 months was measured in a substudy of 309 patients.

RESULTS

At 36 months, significantly more patients in the denosumab arm had increases of >3% BMD from baseline at each site studied compared with placebo (LS, 78 vs 17%; FN, 48 vs 13%; TH, 48 vs 6%; distal 1/3 radius, 40 vs 7% (P<0.0001 for all)). BMD loss at the LS, FN and TH occurred in 1% of denosumab-treated patients vs 42% of placebo patients, and BMD gain at all three sites occurred in 69% of denosumab patients vs 8% of placebo patients. Lower baseline BMD was associated with higher-magnitude BMD responses to denosumab at the LS, FN and TH.

CONCLUSIONS

In men with prostate cancer receiving ADT, significantly higher BMD response rates were observed with denosumab vs placebo. Patients with lower baseline T-scores benefited the most from denosumab treatment.

[Osteoporosis in men receiving androgen deprivation therapy for non-metastatic prostate cancer]

Osteoporosis is defined as a continuous loss of bone mineral density accompanied by an increased fracture risk in females and males. A fall of estrogen concentrations at the menopause and the consecutive rapid bone loss are an established pathogenic mechanism in female osteoporosis. Males do not have a menopause equivalent during which significant amounts of bone are lost. Several diseases, therapeutic strategies and nutritional deficiencies may also result in bone loss and reduced bone mineral density. Prostate cancer is the most common visceral malignancy in men. Suppression of endogenous androgen production as a therapeutic tool is commonly used in patients with non-metastatic prostate cancer and is associated with significant bone loss and an increased fracture risk. Androgen deprivation therapy is prescribed both for men with locally advanced or high-risk non-metastatic prostate cancer. Osteoclast inhibition with any of several bisphosphonates improves bone mineral density and reduces fracture risk. Denosumab (a monoclonal antibody against RANK ligand) and toremifene (a selective estrogen receptor modulator) recently have been shown to be effective to reduce vertebral fractures in patients with non-metastatic prostate cancer receiving androgen-deprivation therapy. This overview focuses on cancer-treatment-induced bone loss in patients with non-metastatic prostate cancer.

Denosumab--a powerful RANKL inhibitor to stop lytic metastases and other bone loss actions by osteoclasts

Denosumab is a perfect example on the targeted anticancer therapy. The inhibition of RANKL activity suppressed the osteoclasts' resorptive function and so prevented skeletal related events. This effect is useful not only against bone metastases, but also in the treatment of other diseases caused by bone loss. In different solid tumors with bone metastasis the quality of life also improved, although the overall survival usually showed no change. On the market the main competitors for denosumab are still the bisphosphonates (questions of costs and reimbursement are not discussed) and some potential new agents e.g. Src kinases (as dasatinib, saracatinib, bosutinib), cathepsin K inhibitors, (e.g. odanacatib), and new selective estrogen receptor modulators (e.g. bazedoxifene, lasofoxifene). Nevertheless, today denosumab is one of the most powerful agents in bone-saving area.

The current practice of screening, prevention, and treatment of androgen-deprivation-therapy induced osteoporosis in patients with prostate cancer

Introduction. ADT is used in the management of locally advanced and metastatic disease. The detrimental effect of ADT on bone density is well documented. This study assesses care gaps in screening, prevention and treatment of osteoporosis among prostate cancer patients. Methods. We conducted a retrospective cohort study for patients diagnosed with non-metastatic prostate cancer on ADT. Charts from a tertiary oncology center were assessed for utilization of DXA scan, prescription of calcium, vitamin D, calcitonin and bisphosphonates.Bivariate analysis was used to determine the effect of patient characteristics and likelihood for osteoporosis screening. Results. 149 charts were reviewed, with 3-year mean follow-up. 58.8% of men received a baseline DXA, of which 20.3% had a repeat DXA within their follow-up periods.In all, 28% were appropriately screened and managed for osteoporosis (received repeat DXA, bisphosphonate). In bivariate analysis, the number of ADT injections which correlate with the duration of androgen suppression was significantly associated with the number of DXA scans. Conclusions. Our study found a care gap in the screening, prevention, and treatment of osteoporosis in this population. Patients receiving the most ADT injections were more likely to be screened. Our results suggest healthcare providers treating prostate cancer are insufficiently screening and treating this susceptible population. We suggest baseline measurement of BMD at the initiation of ADT with periodic reassessment during therapy.

Long-term dynamics of bone mineral density during intermittent androgen deprivation for men with nonmetastatic, hormone-sensitive prostate cancer

PURPOSE

To investigate changes in bone mineral density (BMD) and fracture risk in men who received intermittent androgen deprivation (IAD) for nonmetastatic, hormone-sensitive prostate cancer.

PATIENTS AND METHODS

Men with prostate cancer who lacked radiographically detectable metastases were treated in a prospective trial of IAD. After 9 months of treatment with leuprolide and flutamide, androgen deprivation therapy (ADT) was stopped until prostate-specific antigen reached a threshold (1 ng/mL for radical prostatectomy; 4 ng/mL for radiation or primary ADT) for a new cycle. Dual-energy x-ray absorptiometry (DXA) scans were performed before starting ADT and subsequently with each change in therapy. At least two consecutive DXA scans were required for this analysis. Computed tomography, bone scintigraphy, and lumbar spine x-rays were performed at the beginning and end of each treatment period.

RESULTS

Fifty-six of 100 patients met criteria for this analysis. The median age at study entry was 64.5 years (range, 49.8 to 80.9 years). The average percentage change in BMD during the first on-treatment period was -3.4% (P < .001) for the spine and -1.2% (P = .001) for the left hip. During the first off-treatment period (median, 37.4 weeks; range, 13.4 weeks to 8.7+ years), BMD recovery at the spine was significant, with an average percentage change of +1.4% (P = .002). Subsequent periods had heterogeneous changes of BMD without significant average changes. After a median of 5.5 years (range, 1.1 to 13.8+) years on trial, one patient (1.8%) had a compression fracture associated with trauma.

CONCLUSION

Patients experienced the greatest average change in BMD during early treatment periods of IAD with a smaller average change thereafter. Fractures were rare.

Racial differences in bone mineral density and fractures in men receiving androgen deprivation therapy for prostate cancer

PURPOSE

Whether race influences bone loss and fracture risk during androgen deprivation therapy for prostate cancer is unknown. Using data from a prospective clinical trial we compared bone mineral density and fracture between African-American and Caucasian men receiving androgen deprivation therapy.

MATERIALS AND METHODS

A total of 516 subjects were in the placebo group of a 2-year randomized placebo controlled fracture prevention trial, and were African-American (68) or Caucasian (448). We compared baseline characteristics, changes in bone mineral density and rates of new fractures between races.

RESULTS

Compared to Caucasian men, African-American men had higher baseline hip bone mineral density (mean ± SD 0.98 ± 0.15 vs 0.91 ± 0.15 gm/m(2), p = 0.001) and similar spine bone mineral density (1.09 ± 0.22 vs 1.11 ± 0.22, p = 0.51). There was no difference in prevalent vertebral fractures between African-American and Caucasian men (7.4% vs 15.0%, p = 0.13). The percentage change in hip bone mineral density at 2 years was similar between African-American and Caucasian men (mean ± SE -2.21% ± 0.59% vs -2.54% ± 0.26%, p = 0.65). Changes in bone mineral density of the lumbar spine were also similar between African-American and Caucasian men (-1.74% ± 0.69% vs -1.30% ± 0.33%, p = 0.64). No new vertebral fractures were reported in African-American men but 2 fractures were reported in Caucasian men.

CONCLUSIONS

In a clinical trial African-American men receiving androgen deprivation therapy for prostate cancer have a greater hip bone mineral density and tended to have fewer prevalent vertebral fractures than Caucasian men. Despite a lower baseline risk of osteoporosis and fracture, African-American men experience a decrease in bone mineral density similar to that of Caucasian men.

Denosumab in patients with cancer-a surgical strike against the osteoclast

Elucidation of the molecular pathways underlying bone turnover has revealed potential therapeutic targets, including receptor activator of nuclear factor-κB ligand (RANKL), which is a mediator of osteoclast formation, function and survival. Denosumab is a fully human monoclonal antibody that binds to and inhibits RANKL. This agent has been developed for use in patients with early-stage and advanced-stage cancer, as well as for the treatment of osteoporosis, and can prevent bone loss and reduce fragility fractures in both types of disease. In the bone metastasis setting, several large phase III studies have shown that denosumab is more effective than bisphosphonates, namely zoledronic acid, in reducing skeletal morbidity arising from a wide range of tumors. In addition, a remarkable activity of denosumab has been demonstrated in giant-cell tumors of the bone. Subsequent studies of denosumab have demonstrated that it can delay bone metastasis in patients with castration-resistant prostate cancer; adjuvant studies in patients with breast cancer are in progress. This Review critically explores the emerging role of denosumab in maintaining bone health in the oncology setting, and discusses the factors that are likely to influence the choice between bisphosphonates and denosumab in clinical practice.

Timing of androgen deprivation therapy use and fracture risk among elderly men with prostate cancer in the United States

PURPOSE

Fractures are a recognized consequence of androgen deprivation therapy (ADT); however, less is known about the incidence of fracture in relation to the timing of ADT use or the impact of fracture on mortality in men with prostate cancer.

METHODS

Using data from the Surveillance, Epidemiology, and End Results-Medicare linked database, we estimated adjusted hazard ratios (aHRs) using time-dependent Cox regression for fracture incidence related to the recency of exposure and dose among prostate cancer patients on gonadotropin-releasing hormone (GnRH) agonists, as well as mortality associated with fractures.

RESULTS

In our cohort of 80 844 patients, ADT was associated with an increased rate of fracture in both non-metastatic patients (aHR = 1.34; 95% confidence interval [CI] = 1.29-1.39) and metastatic patients (aHR = 1.51; 95%CI = 1.36-1.67). Fracture rates increased with increasing cumulative GnRH dose but decreased with increasing number of months since last use in each dose category. The mortality rate doubled for men experiencing a fracture after their diagnosis compared with that for men who did not experience a fracture (aHR = 2.05; 95%CI = 1.98-2.12).

CONCLUSIONS

ADT in elderly men with prostate cancer increased the incidence of fractures, and the effect appears to diminish with increasing time since the last dose of a GnRH agonist. Experiencing a fracture after the diagnosis of prostate cancer was associated with decreased survival.

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.

A comprehensive bone-health management approach for men with prostate cancer receiving androgen deprivation therapy

For advanced and metastatic prostate cancer, androgen deprivation therapy (adt) is the mainstay of treatment. Awareness of the potential bone-health complications consequent to adt use is increasing. Many studies have shown that prolonged adt leads to significant bone loss and increased fracture risk that negatively affect quality of life. Clinical practice guidelines for preserving bone health in men with prostate cancer on adt vary across Canada. This paper reviews recent studies on bone health in men with prostate cancer receiving adt and the current evidence regarding bone-health monitoring and management in reference to Canadian provincial guidelines. Based on this narrative review, we provide general bone-health management recommendations for men with prostate cancer receiving adt.

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.

Regulation of postnatal trabecular bone formation by the osteoblast endothelin A receptor

Endothelin-1 (ET-1) is a potent vasoconstrictor that also stimulates cells in the osteoblast lineage by binding to the endothelin A receptor (ETAR). ET-1 ligand is widely secreted, particularly by the vasculature. However, the contributions of ETAR signaling to adult bone homeostasis have not been defined. ETAR was inactivated in osteoblasts by crossing ETAR-floxed and osteocalcin-Cre mice. Histomorphometric analyses were performed on 4-, 8-, and 12-week-old osteoblast-targeted ETAR knockout (KO) and wild-type (WT) male and female mice. Tibial trabecular bone volume was significantly lower from 12 weeks in KO versus WT mice in both males and females. Bone-formation rate, osteoblast density, and in vitro osteoblast differentiation were reduced by targeted inactivation of ETAR. A separate longitudinal analysis was performed between 8 and 64 weeks to examine the effect of aging and castration on bone metabolism in ETAR KO mice. Hypogonadism did not change the rate of bone accrual in WT or KO females. However, eugonadal KO males had a significantly larger increase in tibial and femoral bone acquisition than WT mice. Male mice castrated at 8 weeks of age showed the reverse: KO mice had reduced rates of tibial and femoral BMD acquisition compared with WT mice. In vitro, ET-1 increased osteoblast proliferation, survival, and differentiation. Dihydrotestosterone also increased osteoblast differentiation using a mechanism distinct from the actions of ET-1. These results demonstrate that endothelin signaling in osteoblasts is an important regulator of postnatal trabecular bone remodeling and a modulator of androgen effects on bone.

Efficacy and safety of high-dose-rate brachytherapy of single implant with two fractions combined with external beam radiotherapy for hormone-naïve localized prostate cancer

The purpose of this study was to evaluate the efficacy and safety of high-dose-rate (HDR) brachytherapy of a single implant with two fractions plus external beam radiotherapy (EBRT) for hormone-naïve prostate cancer in comparison with radical prostatectomy. Of 150 patients with localized prostate cancer (T1c–T2c), 59 underwent HDR brachytherapy plus EBRT, and 91 received radical prostatectomy. The median follow-up of patients was 62 months for HDR brachytherapy plus EBRT, and 64 months for radical prostatectomy. In patient backgrounds between the two cohorts, the frequency of T2b plus T2c was greater in HDR brachytherapy cohort than in prostatectomy cohort (27% versus 12%, p = 0.029). Patients in HDR brachytherapy cohort first underwent 3D conformal RT with four beams to the prostate to an isocentric dose of 50 Gy in 25 fractions and then, a total of 15–18 Gy in two fractions at least 5 hours apart. We prescribed 9 Gy/fraction for target (prostate gland plus 3 mm lateral outside margin and seminal vesicle) using CT image method for radiation planning. The total biochemical failure-free control rates (BF-FCR) at 3 and 5 years for the HDR brachytherapy cohort, and for the prostatectomy cohort were 92% and 85%, and 72% and 72%, respectively (significant difference, p = 0.0012). The 3-and 5-year BF-FCR in the HDR brachytherapy cohort and in the prostatectomy cohort by risk group was 100 and 100%, and 80 and 80%, respectively, for the low-risk group (p = 0.1418); 92 and 92%, 73 and 73%, respectively, for the intermediate-risk group (p = 0.0492); and 94 and 72%, 45 and 45%, respectively, for the high-risk group (p = 0.0073). After HDR brachytherapy plus EBRT, no patient experienced Grade 2 or greater genitourinay toxicity. The rate of late Grade 1 and 2 GI toxicity was 6% (n = 4). No patient experienced Grade 3 GI toxicity. HDR brachytherapy plus EBRT is useful for treating patients with hormone-naïve localized prostate cancer, and has low GU and GI toxicities.

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.

Adverse effects of androgen deprivation therapy in prostate cancer: Current management issues

Prostate cancer (CaP) is the most common visceral malignancy and a leading cause of cancer death in men. Androgen deprivation therapy (ADT) is an established treatment for locally advanced and metastatic CaP, and often used as primary therapy in select patients. As ADT has continued to assume an important role in the treatment of CaP, a greater appreciation of potential adverse effects has been acknowledged in men receiving this therapy. Given that all treatments for CaP are frequently associated with some degree of morbidity and can have a negative impact on health-related quality of life (HRQOL), the potential benefits of any treatment, including ADT, must outweigh the risks, particularly in patients with asymptomatic disease. Once the choice to proceed with ADT is complete, it is imperative for the urologist to possess comprehensive knowledge of the potential adverse effects of ADT. This permits the urologist to properly monitor for, perhaps diminish, and to treat any linked morbidities. Patient complaints related to ADT such as a decrease in HRQOL, cognitive and sexual dysfunction, hot flashes, endocrine abnormalities, cardiovascular disease, and alterations in skeletal and body composition are commonly reported throughout the literature. Herein, we review the principal adverse effects linked with ADT in CaP patients and suggest various universal strategies that may diminish these potential adverse consequences associated with this therapy.

[Treatment of metastatic bone disease and treatment-induced osteoporosis in prostate cancer. Evolution of osteoprotective strategies]

Patients with prostate cancer and bone metastases on average experience one skeletal-related event per year. To avoid complications caused by bone metastases and androgen deprivation therapy-induced osteoporosis, which lead to significant increases in costs and mortality, bone metabolism can be influenced in several ways. Bisphosphonates, which directly inhibit signalling pathways in osteoclasts, can reduce the rate of skeletal-related events in metastatic prostate cancer. The RANKL antibody denosumab inhibits the crosstalk between osteoblasts, osteoclasts and tumour cells and has been shown to reduce the rate of vertebral fractures in patients with treatment-induced osteoporosis. Furthermore, it has been recently shown to prevent skeletal-related events in prostate cancer patients with metastatic bone disease. In patients with castration resistant prostate cancer, denosumab prolongs bone-metastasis-free-survival. Whereas ample data are available about side effects of bisphosphonates, limited evidence exists about the long-term safety profile of denosumab. Therefore, a thorough patient selection is advocated for therapeutic application of denosumab in patients with prostate cancer.

Thiazolidinediones and fracture risk in patients with Type 2 diabetes

Thiazolidinediones are widely used effective drugs for the management of hyperglycaemia in Type 2 diabetes and may provide additional metabolic benefits. Any advantages of these agents need to be considered in the context of any potential risk from adverse events. Recent evidence from several sources, including large-scale randomized controlled trials and observational studies, suggests that long-term use of thiazolidinediones is associated with bone loss and an increased risk of fractures in women with Type 2 diabetes. As patients with Type 2 diabetes are already at high risk for fractures, the clinical relevance of this reported association with thiazolidinedione therapy deserves careful consideration. Generally, the fracture risk with thiazolidinediones appears similar in magnitude to that associated with several other widely used drug classes, although there are unanswered questions regarding susceptibility factors, differential effects on bone sites and potential management approaches. This article provides a comprehensive overview of the evidence for an increase in fracture risk with thiazolidinediones and places it in the context of recent analyses of fracture risk with other commonly used drug classes. The potential clinical implications of any association are also discussed.

Factors associated with vertebral fractures in men treated with androgen deprivation therapy for prostate cancer

PURPOSE

Androgen deprivation therapy for prostate cancer causes accelerated loss of bone mineral density and is associated with increased fracture risk. We evaluated risk factors associated with vertebral fractures among men enrolled in a fracture prevention trial.

MATERIALS AND METHODS

Analysis included men receiving androgen deprivation therapy for prostate cancer and enrolled in a phase III fracture prevention trial. All men were 70 years old or older or had a low bone mineral density (T-score less than -1.5 for the lumbar spine or total hip). We analyzed demographic and laboratory characteristics of men with and those without vertebral fractures at study entry.

RESULTS

Of the 1,244 subjects 162 (13.0%) had a vertebral fracture at baseline. The 2 factors significantly associated with vertebral fractures were white race (p=0.028 compared with nonwhite race) and osteoporosis (p=0.002 for osteoporosis at any site, p=0.053 for osteoporosis at the spine, p=0.002 for osteoporosis at the hip). Lower bone mineral density was also significantly associated with vertebral fractures when analyzed as a continuous variable. Factors not associated with vertebral fractures included age, country of residence, androgen deprivation therapy duration at baseline, androgen deprivation therapy mode, body mass index, testosterone, estradiol, C-telopeptide, bone specific alkaline phosphatase and osteocalcin. Results were similar in analyses limited to men 70 years old or older.

CONCLUSIONS

White race and low bone mineral density were significantly associated with vertebral fractures in this study of men treated with androgen deprivation for prostate cancer. These observations should inform the assessment and management of fracture risk among such men.

Contemporary therapeutic approaches targeting bone complications in prostate cancer

Skeletal complications are major causes of morbidity in patients with prostate cancer. Despite the osteoblastic appearance of prostate cancer bone metastases, elevated serum and urinary markers of bone resorption are indicative of high osteoclast activity. Increased osteoclast activity is independently associated with subsequent skeletal complications, disease progression, and death. Osteoclast-targeted therapies aim to reduce the risk for disease-related skeletal complications, bone metastases, and treatment-related fractures. This review focuses on recent advances in osteoclast-targeted therapies in the treatment and prevention of bone complications in prostate cancer. Osteoclast-targeted therapies have been extensively studied in men with prostate cancer. The potent bisphosphonate zoledronic acid significantly decreased the risk of skeletal complications in men with castration-resistant prostate cancer and bone metastases, and is Federal Drug Administration approved for this indication. Denosumab is a human monoclonal antibody that inhibits receptor activator of nuclear factor-κB (RANK) ligand, a critical mediator of osteoclast differentiation, activation, and survival. Data from recent phase III clinic trials demonstrate the emerging role for denosumab in the treatment of prostate cancer bone metastases and prevention of fractures associated with androgen deprivation therapy.

The health and well-being of prostate cancer patients and male-to-female transsexuals on androgen deprivation therapy: a qualitative study with comments on expectations and estrogen

Both male-to-female transsexuals and advanced prostate cancer (PCa) patients are treated with androgen-suppressing drugs that have emasculating effects. Additionally, transsexuals take estrogenic compounds to feminize their bodies. We explore the quality of life of these populations, based on interviews with 12 individuals from each group. Overall, the transsexuals had a better psychological response to chemical castration than the PCa patients. The transsexuals showed more enthusiasm about the changes in their life; they viewed their lives as beginning anew, accepted their reduced libido, and were more comfortable with their increased emotionality. Different responses in the two groups are not surprising given that they undergo androgen deprivation under very different medical contexts. However, the fact that the transwomen are able to conceptualize the effects as positive suggests that some androgen-deprived PCa patients may benefit from reconceptualizing their changes within a positive framework. Additionally, difference in the two populations may be attributed, in part, to the fact that the transsexuals take supplemental estrogen. Circumstantial evidence suggests that estrogen in androgen-deprived males may improve sleep quality, help retain sexual interest, and protect cognitive function. This suggests that PCa patients may benefit from using estradiol for androgen suppression.

[Physiopathology and new therapeutic strategies in the management of bone metastases of prostate cancer]

Prostate cancer (PCa) is one of the most common human malignancies that have a strong propensity to spread in the bones. Despite the progress in the diagnosis and the treatment of prostate cancer, bone metastases are present in nearly 95% of men with metastatic PCa at autopsy. Bone metastases are a major cause of skeletal complications which may negatively affect the quality of life and increase morbidity and mortality in men with advanced PCa. Bisphosphonates are potent inhibitors of bone resorption that have demonstrated clinical benefit for the treatment of bone metastases. They are standard of care for the prevention of skeletal complications such as pain and pathological fractures in patients with bone metastases from PCa. More recently, the discovery of the OPG/RANK/RANKL system has permitted to better understand the role of OPG and RANKL as key regulators of osteoclast-mediate bone destruction in both normal bone remodelling and pathologic conditions. RANKL has been shown to contribute to the vicious cycle of bone destruction and tumour growth in PCa. Therefore, the development of new emerging treatment that inhibits RANKL using RANKL antibodies, as denosumab, resulted in a better control and treatment of skeletal complications, with the hope in a near future to prevent bone metastases.

Treatment and prevention of bone complications from prostate cancer

Bone metastases and skeletal complications are major causes of morbidity in prostate cancer patients. Despite the osteoblastic appearance of bone metastases on imaging studies, patients have elevated serum and urinary markers of bone resorption, indicative of high osteoclast activity. Increased osteoclast activity is independently associated with higher risk of subsequent skeletal complications, disease progression, and death. Osteoclast-targeted therapies are therefore a rational approach to reduction of risk for disease-related skeletal complications, bone metastases, and treatment-related fractures. This review focuses on recent advances in osteoclast-targeted therapy in prostate cancer. Bisphosphonates have been extensively studied in men with prostate cancer. Zoledronic acid significantly decreased the risk of skeletal complications in men with castration-resistant prostate cancer and bone metastases, and it is FDA-approved for this indication. Denosumab is a human monoclonal antibody that binds and inactivates RANKL, a critical mediator of osteoclast differentiation, activation, and survival. Recent global phase 3 clinic trials demonstrated an emerging role for denosumab in the treatment of prostate cancer bone metastases and prevention of fractures associated with androgen deprivation therapy.

RANKL-Targeted Therapies: The Next Frontier in the Treatment of Male Osteoporosis

Male osteoporosis is an increasingly recognized problem in aging men. A common cause of male osteoporosis is hypogonadism. Thousands of men with prostate cancer are treated with androgen deprivation therapy, a treatment that dramatically reduces serum testosterone and causes severe hypogonadism. Men treated with androgen deprivation therapy experience a decline in bone mineral density and have an increased rate of fracture. This paper describes prostate cancer survivors as a model of hypogonadal osteoporosis and discusses the use of RANKL-targeted therapies in osteoporosis. Denosumab, the only RANKL-targeted therapy currently available, increases bone mineral density and decreases fracture rate in men with prostate cancer. Denosumab is also associated with delayed time to first skeletal-related event and an increase in bone metastasis-free survival in these men. It is reasonable to investigate the use of RANKL-targeted therapy in male osteoporosis in the general population.

Emerging drugs for the management of cancer treatment induced bone loss

AREAS COVERED IN THIS REVIEW

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

IMPORTANCE OF THE FIELD

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

WHAT THE READER WILL GAIN

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

TAKE HOME MESSAGE

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

Drug-induced osteoporosis in the older adult

The elderly population is at risk for polypharmacy and, therefore, also at risk for drug-induced osteoporosis (DIOP). Epidemiologic studies provide valuable information about medications that may place patients at risk for DIOP. While glucocorticoids are the most common cause of DIOP, the use of several other therapeutic agents can place patients at risk for significant bone loss and fracture. These medications include, but are not limited to, aromatase inhibitors, gonadotropin-releasing hormone agonists, thyroid replacement therapy, antiepileptics, antidepressants, antipsychotics, lithium, gastric acid lowering agents, thiazolidinediones, loop diuretics, heparins and warfarin, vitamin A and cyclosporine. This article provides information about their mechanism of action, studies that have evaluated these agents in DIOP and prevention and treatment strategies.

Bone continuum of cancer

Many patients with solid tumors, especially breast and prostate cancers, and with multiple myeloma will develop bone metastases or other skeletal complications. The management of bone loss and symptomatic bone metastases is an important issue in the care and maintenance of quality of life for these patients. Morbidity caused by skeletal complications include pain (bone metastases are known as the most common cause of cancer-related pain), hypercalcemia, pathologic fracture, compression of the spinal cord or cauda equine, and spinal instability. Currently, the only Food and Drug Administration-approved therapy for metastatic bone disease is bisphosphonate therapy. A greater understanding of the biomolecular pathways that govern the bone continuum of cancer has helped identify novel targets for drug development. New therapeutic options are currently being investigated for the treatments of bone loss and symptomatic bone metastases. Some of these new drugs and modalities are in advanced stages of clinical development and may soon reach the clinic.

Application of a fracture risk algorithm to men treated with androgen deprivation therapy for prostate cancer

PURPOSE

Osteoporosis causes morbidity and mortality in men. The National Osteoporosis Foundation recommends fracture risk assessment with the online WHO/FRAX tool. Although androgen deprivation therapy for prostate cancer increases fracture risk, there is limited information about which men require preventative drug therapy. We applied the WHO/FRAX tool to men treated with androgen deprivation therapy for prostate cancer.

MATERIALS AND METHODS

Information was collected from a practice cohort of men treated with gonadotropin-releasing hormone agonists, and included age, height, weight, history of gonadotropin-releasing hormone agonist treatment, dual energy x-ray absorptiometry results, prior bone targeted therapy and clinical risk factors for fracture. Subjects were evaluated with the WHO/FRAX algorithm (http://www.shef.ac.uk/FRAX/).

RESULTS

A total of 363 men treated with androgen deprivation therapy (median age 72 years) were evaluated. By the FRAX algorithm with clinical information (no dual energy x-ray absorptiometry data) the 3% hip fracture risk threshold for treatment was exceeded by 51.2% of the men (median risk 3.1%). When subjects were grouped by age the treatment threshold was reached by 3.3% of those younger than 70 years, 76.6% of those 70 to 79 years old and by 98.8% of those 80 years old or older. Using FRAX with bone mineral density data in the 93 patients who underwent bone mineral density testing the median 10-year hip fracture risk was 0.9% and the treatment threshold was exceeded by 15% of these subjects.

CONCLUSIONS

In this cohort of men receiving androgen deprivation therapy the prevalence of risk sufficient to necessitate drug therapy was high and was strongly influenced by age. The WHO/FRAX algorithm identifies a greater proportion of men for treatment than the traditional threshold of T score -2.5 or less.

Metabolic sequelae associated with androgen deprivation therapy for prostate cancer

PURPOSE OF REVIEW

To summarize the metabolic alterations associated with androgen deprivation therapy (ADT) for prostate cancer and to evaluate the evidence linking ADT with an increased risk of diabetes and cardiovascular disease.

RECENT FINDINGS

ADT by either bilateral orchiectomy or treatment with gonadotropin-releasing hormone agonists causes changes in body composition, alterations in lipid profiles, and decreased insulin sensitivity. The spectrum of metabolic changes during ADT is distinct from classically described metabolic syndrome. Population-based, linked cancer registry studies have consistently reported significant associations between ADT and greater risk for diabetes mellitus. Some but not all studies have reported a link between ADT and cardiovascular disease risk. Most studies have reported no increase in cardiovascular mortality following ADT.

SUMMARY

ADT appears causally associated with diabetes mellitus. ADT is also linked to cardiovascular morbidity, although there is less evidence that this relationship is causal.

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

BACKGROUND

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

OBJECTIVE

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

DESIGN

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

DATA SOURCES

Published literature.

TARGET POPULATION

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

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTION

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

OUTCOME MEASURES

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

RESULTS OF BASE-CASE ANALYSIS

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

RESULTS OF SENSITIVITY ANALYSES

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

LIMITATIONS

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

CONCLUSION

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

Treatment thresholds for osteoporosis in men on androgen deprivation therapy: T-score versus FRAX

Men treated by androgen deprivation therapy (ADT) for localized prostate cancer are at risk for fracture, but it is not known which men require pharmacologic treatment. We found that 33% of men on ADT had osteoporosis of spine, hip, or forearm by dual-energy X-ray absorptiometry (DXA), thus requiring treatment. Using the new fracture prediction algorithm (FRAX) tool with corrected femoral neck T-score identified only 17% requiring treatment, and, if calculated without femoral neck, 54% were identified to need treatment.

INTRODUCTION

Men treated with androgen deprivation therapy (ADT) for prostate carcinoma live long enough to fracture. A new fracture prediction method, FRAX, is based on femoral neck DXA plus risk factors. Thus, DXA or FRAX could determine which men should receive osteoporosis therapy.

METHODS

Of 115 men undergoing ADT referred for DXA testing, those with bone mineral density (BMD) in spine, hip, or forearm of >or=2.5 standard deviations below a normal male ethnicity-adjusted mean were considered treatment candidates. Using FRAX with and without femoral neck BMD, men were treatment candidates if the 10-year hip fracture risk was >or=3% or the major osteoporotic fracture risk was >or=20%.

RESULTS

The men averaged 77 years old; 58% were African-American, and 14.8% were current smokers. Mean femoral neck T-score was -1.4. Using DXA, 38 (33%) men would need treatment. When FRAX was calculated including the femoral neck T-score, only 20 men met criteria for treatment. However, when FRAX was calculated without the T-score, 62 men met criteria for treatment. Overlap among the groups was surprisingly modest.

CONCLUSIONS

DXA and FRAX identify different ADT men for treatment.

Bone health and prostate cancer

Bone metastases are a substantial burden to men with advanced prostate cancer as they often cause pain and can cause fractures and spinal cord compression. Osteoblasts and osteoclasts are both pathologically activated in the setting of prostate cancer bone metastases. As osteoclast activation is associated with disease progression, skeletal complications and death, osteoclast-targeted therapies are a rational approach to disease management. Zoledronic acid is standard of care for castration-resistant prostate cancer with bone metastases as it reduces the risk for skeletal-related events. Additional trials are needed to better define the ideal dose, frequency and duration of zoledronic acid therapy. No bisphosphonate has yet been shown to prevent bone metastases or to benefit men with androgen-sensitive disease. Denosumab is an experimental osteoclast-targeted monoclonal antibody against receptor activator of nuclear factor-kappaB ligand. Two ongoing phase III trials are expected to define its efficacy in preventing bone metastases and disease-related skeletal events in men with prostate cancer. Androgen-deprivation therapy (ADT) for prostate cancer is associated with osteoporosis and fragility fractures. Several bisphosphonates have been shown to improve bone mineral density in men receiving ADT. Two recent phase III trials have shown that denosumab and toremifene reduce the incidence of fragility fractures in these men. The World Health Organization has developed a fracture risk assessment model (FRAX) for the general population to guide the selection of patients who may benefit from pharmacotherapy. In the absence of a prostate cancer-specific algorithm, we advocate the use of FRAX for men receiving ADT.

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

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

Background for the proposal of SIOG guidelines for the management of prostate cancer in senior adults

BACKGROUND

The incidence of prostate cancer increases with age, with a median age at diagnosis of 68 years. Owing to increased life expectancy, the management of prostate cancer in senior adult men (i.e., aged 70 years or older) represents an important public health concern and a major challenge for the future. No specific guidelines have previously been published on the management of prostate cancer in older men. The SIOG has developed a proposal of recommendations in this setting.

METHODS

A systematic bibliographical search focused on screening, diagnostic procedures, treatment options for localised, locally advanced and metastatic prostate cancer in senior adults was performed. Specific aspects of the geriatric approach were emphasised, including evaluation of health status (nutritional, cognitive, thymic, physical and psycho-social) and screening for vulnerability and frailty. Attention was drawn to the consequences of androgen deprivation and complications of local treatment, mainly incontinence. The collected material has been reviewed and discussed by a scientific panel including urologists, radiation oncologists, medical oncologists and geriatricians from both Europe and North America.

RESULTS

The consensus is to use either European Association of Urology or National Comprehensive Cancer Network clinical recommendations for prostate cancer treatment and to adapt them to health status based on instrumental activities of daily living (IADL) and activities daily living (ADL), comorbidity evaluation by Cumulative Illness Scoring Rating-Geriatrics and screening for malnutrition. Patients in Group 1 (no abnormality) are 'fit' and should receive the same treatment as younger patients; patients in Group 2 (one impairment in IADL or one uncontrolled comorbidity or at risk of malnutrition) are 'vulnerable' and should receive standard treatment after medical intervention; patients in Group 3 (one impairment in ADL or more than one uncontrolled comorbidity or severe malnutrition) are 'frail' and should receive adapted treatment; patients in Group 4 (dependent) should receive only symptomatic palliative treatment.

CONCLUSIONS

Treatment of prostate cancer in senior adults should be adapted to health status. Specific prospective studies in this setting are warranted.

New results from the use of bisphosphonates in cancer patients

PURPOSE OF REVIEW

Metastatic bone disease results from cancer-bone cell interactions in the bone marrow microenvironment rather than direct destruction by cancer cells. Additionally, cancer treatments may have adverse effects on bone health. Therefore, a clear rationale exists for bone-targeted therapies to prevent skeletal complications and potentially modify the underlying disease.

RECENT FINDINGS

Studies in metastatic disease have focused on refining treatment, largely through the use of bone metabolism markers. Use of bisphosphonates in early cancer has become increasingly important to prevent bone loss. Recent results, notably with zoledronic acid, indicate that bone mineral density can be maintained and increased bone turnover normalized. Bisphosphonates are potent inhibitors of bone osteolysis and may impede both the development of bone metastases and survival of dormant cells in the marrow microenvironment. Additionally, bisphosphonates may have direct effects on tumour cells, especially in combination with chemotherapy. Clinical trial results in breast cancer with clodronate were inconclusive, but recent data with zoledronic acid suggest that bisphosphonates may indeed modify the course of the disease.

SUMMARY

The roles of bisphosphonates in metastatic bone disease and the prevention of cancer treatment induced bone loss have been defined. However, results from ongoing metastasis prevention trials are required before routine adjuvant bisphosphonates can be recommended.

Correlates of trabecular and cortical volumetric BMD in men of African ancestry

QCT provides a measure of volumetric BMD (vBMD) and distinguishes trabecular from cortical bone. Few studies have determined the factors related to vBMD in men, especially among men of African heritage. This study evaluated the relationship of anthropometric, medical, and behavioral factors and vBMD in a population-based cohort of men of African ancestry (n = 1901) >or=40 yr of age who had undergone screening for prostate cancer for the first time. Trabecular and cortical vBMD were measured at the radius and tibia by pQCT. Multiple linear regression analysis identified age, height, body weight, cigarette smoking, history of diabetes, fracture, and prostate cancer as the independent correlates of vBMD. However, associations with several variables differed between cortical and trabecular vBMD and between the radius and tibia. Longitudinal studies are needed to gain a better understanding of the mechanisms underlying these differential associations that may show new insight into the etiology of trabecular and cortical bone loss in men.

Prostate cancer survivorship: prevention and treatment of the adverse effects of androgen deprivation therapy

BACKGROUND

More than one-third of the estimated 2 million prostate cancer survivors in the United States receive androgen deprivation therapy (ADT). This population of mostly older men is medically vulnerable to a variety of treatment-associated adverse effects.

MEASUREMENTS AND RESULTS

Androgen-deprivation therapy (ADT) causes loss of libido, vasomotor flushing, anemia, and fatigue. More recently, ADT has been shown to accelerate bone loss, increase fat mass, increase cholesterol and triglycerides, and decrease insulin sensitivity. Consistent with these adverse metabolic effects, ADT has also recently been associated with greater risks for fractures, diabetes and cardiovascular disease.

CONCLUSION

Primary care clinicians and patients should be aware of the potential benefits and harms of ADT. Screening and intervention to prevent treatment-related morbidity should be incorporated into the routine care of prostate cancer survivors. Evidence-based guidelines to prevent fractures, diabetes, and cardiovascular disease in prostate cancer survivors represent an important unmet need. We recommend the adapted use of established practice guidelines designed for the general population.

Intravenous zoledronic acid to prevent osteoporosis in a veteran population with multiple risk factors for bone loss on androgen deprivation therapy

PURPOSE

Androgen deprivation therapy for prostate cancer is associated with osteoporosis and increased fracture risk. Previous studies of zoledronic acid demonstrated bone loss prevention in patients initiating androgen deprivation therapy. There are limited data on patients on prolonged androgen deprivation therapy or in Veterans Affairs patients with multiple risk factors for osteoporosis.

METHODS

We randomized 93 patients with M0 prostate cancer in this placebo controlled trial in the Veterans Affairs health care system. Preplanned strata included 50 patients on androgen deprivation therapy for less than 1 year (stratum 1) and 43 on androgen deprivation therapy for greater than 1 year (stratum 2). In each stratum patients were randomized to 4 mg zoledronic acid intravenously every 3 months for 4 treatments or intravenous placebo. The primary end point was the percent change in bone mineral density at the lumbar spine at 12 months.

RESULTS

Age, race, body mass index and osteoporosis risk factors were similar for the 2 treatments. Most patients were former smokers, had moderate alcohol intake, were not on calcium/vitamin D supplements and were relatively sedentary at baseline. In stratum 1 spine bone mineral density increased 5.95% in the zoledronic acid arm and decreased 3.23% in the placebo arm (p = 0.0044). In stratum 2 spine bone mineral density increased 6.08% in the zoledronic acid arm and only increased 1.57% in the placebo arm (p = 0.0005). Treatment was well tolerated with minimal impact on renal function.

CONCLUSIONS

Zoledronic acid improved bone mineral density in patients with M0 prostate cancer on androgen deprivation therapy for 1 year or less, or greater than 1 year. This finding indicates that bisphosphonate therapy remains effective when initiated later in the course of androgen deprivation therapy and is efficacious in Veterans Affairs patients with multiple risk factors for osteoporosis.

Review of major adverse effects of androgen-deprivation therapy in men with prostate cancer

Androgen-deprivation therapy (ADT) is a common treatment for men with prostate cancer. Although ADT is effective at suppressing prostate-specific antigen (PSA), stabilizing disease, alleviating symptoms in advanced disease, and potentially prolonging survival, it is not without serious side effects. However, to the authors' knowledge, there is lack of a systematic review of its major adverse effects to date. The authors of this report systematically reviewed and quantitatively assessed the literature on skeletal and cardiac side effects associated with ADT in men with prostate cancer. The PubMed database was searched for relevant published articles from 1966 to May 2008, and 683 articles were reviewed systematically from an original 20 different Medical Subject Heading search combinations. The focus of the review was on bone-related and cardiovascular-related outcomes. When appropriate, results were pooled from articles on specific adverse outcomes, summary risk estimates were calculated, and tests of heterogeneity were performed. Fourteen articles were identified that met inclusion criteria from the original 683 studies. Men who underwent ADT for prostate cancer had a significantly increased risk of overall fracture of 23% (summary relative risk, 1.23; 95% confidence interval [95% CI], 1.10-1.38) compared with men who had prostate cancer but who did not undergo ADT. Furthermore, men who underwent ADT had a 17% increase in cardiovascular-related mortality compared with men who did not undergo with ADT (summary hazards ratio, 1.17; 95% CI, 1.07-1.29). Significant elevations in the risk of diabetes also were observed from 2 large studies. ADT was associated with an increased risk of skeletal fracture, incident diabetes, and cardiovascular-related mortality, although the absolute risk of these events was low. Preventive measures against these adverse effects and careful assessment of patient's baseline health status should be considered.

Natural history and correlates of hip BMD loss with aging in men of African ancestry: the Tobago Bone Health Study

Little is known about the magnitude, pattern, and determinants of bone loss with advancing age among men, particularly among those of African descent. We examined the rate of decline in hip BMD and identified factors associated with BMD loss among 1478 Afro-Caribbean men >or=40 yr of age. BMD was measured at baseline and after an average of 4.4 yr by DXA. The rate of decline in femoral neck BMD was 0.29 +/- 0.81%/yr in the total sample (p < 0.0001). However, a U-shaped relationship between advancing age and the rate of decline in BMD was observed. The rate of decline in BMD at the femoral neck was -0.38 +/- 0.77%/yr among men 40-44 yr of age, decelerated to -0.15 +/- 0.81%/yr among men 50-54 yr of age, and then accelerated to -0.52 +/- 0.90%/yr among those 75+ yr of age (all p < 0.003). Men who lost >or=5% of their body weight during follow-up had significantly greater BMD loss than those who remained weight stable or gained weight (p < 0.0001). The relationship between weight loss and BMD loss was more pronounced among men who were older and leaner at study entry (p < 0.03). We also observed a strong impact of advanced prostate cancer and its treatment with androgen deprivation on BMD loss. Men of African ancestry experience substantial BMD loss with advancing age that seems to be comparable to the rate of loss among white men in other studies. Additional studies are needed to better define the natural history and factors underlying bone loss with aging in men of African ancestry.

Impact of androgen deprivation therapy on cardiovascular disease and diabetes

PURPOSE Use of androgen deprivation therapy (ADT) may be associated with an increased risk of diabetes mellitus but the risk of both acute myocardial infarction (AMI) and cardiovascular mortality remain controversial because few outcomes and conflicting findings have been reported. We sought to clarify whether ADT is associated with these outcomes in a large, representative cohort. METHODS Using linked administrative databases in Ontario, Canada, men age 66 years or older with prostate cancer given continuous ADT for at least 6 months or who underwent bilateral orchiectomy (n = 19,079) were matched with men with prostate cancer who had never received ADT. Treated and untreated groups were matched 1:1 (ie, hard-matched) on age, prior cancer treatment, and year of diagnosis and propensity-matched on comorbidities, medications, cardiovascular risk factors, prior fractures, and socioeconomic variables. Primary outcomes were development of AMI, sudden cardiac death, and diabetes. Fragility fracture was also examined. Results The cohort was observed for a mean of 6.47 years. In time-to-event analyses, ADT use was associated with an increased risk of diabetes (hazard ratio [HR], 1.16; 95% CI, 1.11 to 1.21) and fragility fracture (HR, 1.65; 95% CI, 1.53 to 1.77) but not with AMI (HR, 0.91; 95% CI, 0.84 to 1.00) or sudden cardiac death (HR, 0.96; 95% CI, 0.83 to 1.10). Increasing duration of ADT was associated with an excess risk of fragility fractures and diabetes but not cardiac outcomes. CONCLUSION Continuous ADT use for at least 6 months in older men is associated with an increased risk of diabetes and fragility fracture but not AMI or sudden cardiac death.

Skeletal sequelae of cancer and cancer treatment

INTRODUCTION

Survivors of cancer may experience lingering adverse skeletal effects such as osteoporosis and osteomalacia. Skeletal disorders are often associated with advancing age, but these effects can be exacerbated by exposure to cancer and its treatment. This review will explore the cancer and cancer treatment-related causes of skeletal disorders.

METHODS

We performed a comprehensive search, using various Internet-based medical search engines such as PubMed, Medline Plus, Scopus, and Google Scholar, for published articles on the skeletal effects of cancer and cancer therapies.

RESULTS

One-hundred-forty-two publications, including journal articles, books, and book chapters, met the inclusion criteria. They included case reports, literature reviews, systematic analyses, and cohort reports. Skeletal effects resulting from cancer and cancer therapies, including hypogonadism, androgen deprivation therapy, estrogen suppression, glucocorticoids/corticosteroids, methotrexate, megestrol acetate, platinum compounds, cyclophosphamide, doxorubicin, interferon-alpha, valproic acid, cyclosporine, vitamin A, NSAIDS, estramustine, ifosfamide, radiotherapy, and combined chemotherapeutic regimens, were identified and described. Skeletal effects of hyperparathyroidism, vitamin D deficiency, gastrectomy, hypophosphatemia, and hyperprolactinemia resulting from cancer therapies were also described.

DISCUSSION/CONCLUSIONS

The publications researched during this review both highlight and emphasize the association between cancer therapies, including chemotherapy and radiotherapy, and skeletal dysfunction.

IMPLICATIONS FOR CANCER SURVIVORS

These studies confirm that cancer survivors experience a more rapid acceleration of bone loss than their age-matched peers who were never diagnosed with cancer. Further studies are needed to better address the skeletal needs of cancer survivors.

Survival outcomes in men receiving androgen-deprivation therapy as primary or salvage treatment for localized or advanced prostate cancer: 20-year single-centre experience

OBJECTIVES

To evaluate the overall survival (OS) and disease-specific survival (DSS) in men receiving primary androgen-deprivation therapy (PADT) or salvage medical ADT (SADT) for prostate cancer.

PATIENTS AND METHODS

After Institutional Review Board approval, we retrospectively reviewed patients receiving ADT for prostate cancer between July 1987 and June 2007. Variables included age at diagnosis and ADT induction, race, PSA level before ADT, ADT schedule (continuous/intermittent), clinical/pathological stage, hormone-refractory prostate cancer (HRCP) status, PADT or SADT, and deaths.

RESULTS

In all, 548 men were analysed. The mean age at diagnosis and ADT induction were 70.1 and 72.3 years, respectively, and 321 (58.6%) were African-American. The median PSA level before ADT was 16.3 ng/mL. ADT was administered continuously in 497 (90.7%) patients; 342 (62.4%) received PADT while 206 (37.6%) received SADT. At mean (range) follow-up of 81.8 (2.1-445) months, 98 (17.9%) deaths occurred; 31 (31.6%) were cancer-specific. The OS and DSS in the PADT and SADT groups were not significantly different (P = 0.36 and P = 0.81, respectively). Mortality rates/distributions were similar between groups (P = 0.68). Multivariate predictors of OS and DSS included age at diagnosis (P = 0.03) and ADT induction (P = 0.009), tumour stage (P < 0.001), and PSA level at ADT induction (P = 0.01). Progression to HRPC worsened OS and DSS (both P < 0.001).

CONCLUSION

PADT and SADT prolong survival in men with prostate cancer. HRPC portends a poor DSS. Age at diagnosis and ADT induction, PSA level before ADT, and disease stage predict both OS and DSS in this population. However, most men died from causes unrelated to prostate cancer, thus questioning the true value of ADT in prolonging patient survival.