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

Cancer treatment-related bone loss: a review and synthesis of the literature

Cancer therapy can result in significant bone loss and increased risk of fragility fracture. Chemotherapy, aromatase inhibitors, and gonadotropin-releasing hormone analogues contribute to increases in the rate of bone remodelling and reduce bone mineral density. Patients with prostate cancer on androgen deprivation therapy experience an increase in the risk of fracture. New research has demonstrated the key role played by bisphosphonates in preventing declines in bone density and increases in bone remodelling. Novel antiresorptive agents targeting receptor activator of nuclear factor κB ligand have great potential in skeletal protection and prevention of bone loss related to cancer therapy. Early assessment of skeletal health, followed by initiation of calcium, vitamin D, and an exercise program are valuable in the prevention and treatment of osteoporosis. In addition, individuals at increased risk for fracture should be offered antiresorptive therapy. Early data have demonstrated that bisphosphonates are able to prevent the bone loss and increased bone remodelling associated with cancer therapy, including aromatase inhibition and androgen deprivation therapy. The present paper reviews the new research and advances in the management of bone loss associated with both cancer therapy and estrogen deficiency in the postmenopausal female.

Prevention and management of osteoporosis in women with breast cancer and men with prostate cancer

Advances in cancer treatment have resulted in improved life expectancies for survivors of breast and prostate cancer. As the number of cancer survivors grows, the long-term side effects of treatment play an increasingly prominent role in the routine care of these patients. Due to similar management approaches, survivors of breast and prostate cancer are at increased risk for osteoporosis. This review summarizes the prevention and management of osteoporosis and osteopenia resulting from cancer treatment in survivors of breast and prostate cancer.

Management of cancer treatment-induced bone loss in early breast and prostate cancer -- a consensus paper of the Belgian Bone Club

Cancer treatment-induced bone loss (CTIBL) is one of the most important side effects of adjuvant antineoplastic treatment in hormone-dependent neoplasms. Chemotherapy, GnRH analogs and tamoxifen can induce marked bone loss in premenopausal women with early breast cancer. Aromatase inhibitors (AIs) are replacing tamoxifen as the preferred treatment for postmenopausal women. As a class effect, steroidal (exemestane) and non-steroidal (anastrozole and letrozole) AIs increase bone turnover and cause bone loss (4%-5% over 2 years). When compared to tamoxifen, the risk of getting a clinical fracture under AI treatment is increased by 35%-50%. In patients with prostate cancer, androgen deprivation therapy (ADT) increases bone turnover, reduces bone mass (4%-5% per year) and increases the fracture rate depending on the duration of therapy. Zoledronic acid can prevent accelerated bone loss induced by goserelin in premenopausal women, by letrozole in postmenopausal women and by ADT in men. More limited data indicate that weekly alendronate or risedronate could also be effective for preventing CTIBL. Initiation of therapy early, prior to the occurrence of severe osteoporosis, rather than after, may be more effective. Bisphosphonate treatment should be considered in osteoporotic but also in osteopenic patients if other risk factor(s) for fractures are present.

The role of tumor microenvironment in prostate cancer bone metastasis

Prostate cancer (PCa) epithelial cells require a number of factors to facilitate their establishment and growth at a distant site of metastasis. Their ability to adapt to their microenvironment, proliferate and recruit an underlying stroma is integral to the survival and growth of the metastasis. PCa predominantly metastasizes to the bone, and bone metastases are the main cause of morbidity. The bone marrow provides a permissive environment for the formation of a metastasis. In some cases, the cells may remain dormant for some time, eventually proliferating in response to an unknown "trigger." The marrow is rich in progenitor cells that differentiate into numerous cell types, producing new blood vessels, supporting fibroblasts, and an underlying extracellular matrix (ECM) that form the reactive stroma. By secreting a number of cytokines, growth factors and proteases they recruit auxiliary cells required to produce a functional stroma. These components are involved in a reciprocal interaction between the stroma and the PCa cells, allowing for the growth and survival of the tumor. Left unchecked, once a PCa tumor has established itself in the bone marrow it will eventually replace the marrow, interrupting bone homeostasis and typically promoting an osteoblastic response in the bone including osteoclastic events. The abundant deposition of new woven bone results in nerve compression, bone pain and an increase in fractures in patients with PCa bone metastases. This review will examine the tumor microenvironment, its role in facilitating tumor dissemination, growth and the resultant pathologies associated with PCa bone metastasis.

Osteoporosis management in prostate cancer patients treated with androgen deprivation therapy

BACKGROUND

The use of androgen deprivation therapy (ADT) for prostate cancer has increased substantially in recent years, exposing more men to potential treatment complications, including osteoporosis and fractures.

OBJECTIVE

To determine whether men treated with ADT for prostate cancer received osteoporosis screening, prevention, or treatment.

DESIGN

Cross-sectional observational study using a retrospective review of electronic medical records.

SUBJECTS

One hundred seventy-four patients with prostate cancer on ADT or status-post orchiectomy enrolled in primary care at the New Mexico Veterans Affairs Health Care System as of July 2005.

MEASUREMENTS

Patient demographics, tumor characteristics (Gleason score, stage, last PSA value, documented bone metastases), history of hip or vertebral fracture, osteoporosis risk factors (number of ADT shots, diabetes, smoking, heavy alcohol use or prescriptions for corticosteroids, thyroid hormone or dilantin). We defined recommended management as performing DXA scans or prescribing bisphosphonates, calcitonin, calcium or vitamin D.

RESULTS

Just 60 of 174 (34%) patients received recommended osteoporosis management based on DXA scans (13%) or treatment with oral or IV bisphosphonates (21%), calcitonin (1%), calcium (16%) or vitamin D (10%). On multivariate analysis, bone metastases, higher last PSA, and younger age at diagnosis were associated with recommended management, whereas Hispanic race/ethnicity was inversely associated.

CONCLUSIONS

Most men treated with ADT for prostate cancer did not receive osteoporosis screening, prevention or treatment. Evidence for advanced cancer though not risk factors for osteoporosis or fracture-was associated with receiving osteoporosis management. Further research is needed to identify optimal strategies for screening, prevention, and treatment in this population.

Tendon abnormalities mimicking metastatic disease in patients with prostate cancer

We present plain x-ray examination, bone scintigraphy, computed tomography, and magnetic resonance imaging of 2 patients diagnosed with prostate cancer who complained of hip pain. Bone scintigraphy was suggestive for metastases. Further radiologic investigation revealed benign etiologies for the hip pain; calcific tendinitis of the vastus lateralis and tendonosis of the gluteus medius tendon were visualized.

[Systemic therapy approaches in patients with bone metastases of urogenital malignancies]

Bone metastases develop commonly in patients with a variety of urogenital malignancies and are a major cause of morbidity and diminished quality of life in a significant proportion of urogenital carcinoma patients. For example, bone metastases occur in approximately 80% of patients with hormone-refractory prostate cancer and in approximately 25% of patients with renal cell carcinoma. A sufficient and early therapy is crucial since adequate therapy can lead to significant improvements in pain control and function and maintain skeletal integrity. The effective treatment of bone metastases requires multidisciplinary cooperation between urologists, oncologists, surgeons, nuclear medicine physicians and radiation oncologists. Analgesic measures, bisphosphonates, radionuclides, radiation therapy as well as surgical procedures are available. This review will focus mainly on the role of analgetics, bisphosphonates, radionuclides and radiolabelled bisphosphonates in the treatment of bone metastases.

Androgen deprivation therapy for prostate cancer: new concepts and concerns

PURPOSE OF REVIEW

The aim of this review is to summarize new concepts and concerns regarding treatment-related osteoporosis, diabetes, and cardiovascular disease in men receiving androgen deprivation therapy for prostate cancer.

RECENT FINDINGS

Gonadotropin-releasing hormone agonists increase bone turnover, decrease bone mineral density, and increase fracture risk. Bisphosphonates, selective and estrogen receptor modulators significantly increase bone mineral density during androgen deprivation therapy. Ongoing randomized controlled trials will assess efficacy of denosumab, toremifene, and zoledronic acid to prevent fractures in this setting. Gonadotropin-releasing hormone agonists also increase fat mass, decrease insulin sensitivity, and increase serum lipoproteins. In contrast to the classical metabolic syndrome, however, the phenotype of men during androgen deprivation therapy is characterized by increased high-density lipoprotein cholesterol and preferential accumulation of subcutaneous fat. Gonadotropin-releasing hormone agonists are associated with greater risk of incident diabetes and cardiovascular disease in men with prostate cancer.

SUMMARY

Androgen therapy increases risk of fractures, diabetes mellitus, and cardiovascular disease in men with prostate cancer. Current and planned studies will evaluate strategies to prevent these treatment-related adverse effects.

[Bisphosphonates in oncology]

Since bone metastases occur as a result of hematogenous spreading of tumor cells, therapy with curative intent is no longer feasible and palliative options for treating and preventing skeletal events are essential. Today, bisphosphonates are established in the systemic treatment of bone metastases. This report provides an overview of molecular mechanisms of action and clinical data of bisphosphonates in patients with skeletal metastases of breast and prostate cancer as the most common solid tumors which spread to the bone.

Palliative und supportive Therapie bei Patienten mit fortgeschrittenem Prostatakarzinom

In patients with advanced prostate cancer, quality of life and prevention of complications come to the fore. Besides handling local complications such as obstruction, hematuria and lymphedema, treatment of bone metastases and their complications is of great importance. Analgesic measures, bisphosphonates, radiation therapy, radionuclide therapy and neurosurgical procedures are available. Spinal cord compression with acute motor and sensory deficiency requires immediate neurosurgical and/or radiation therapy. Tumor anemia should be treated appropriately.

Trabecular bone microarchitecture is related to the number of risk factors and etiology in osteoporotic men

Microarchitecture of trabecular bone is a very important component of bone quality in osteoporosis and a determinant of vertebral fracture in men with low bone mineral density (BMD). In contrast to women, male osteoporosis is, in most cases, secondary. The relationships between microarchitecture and different risk factors have never been evaluated in men. About 152 men with low BMD at the lumbar spine or hip (BMD, T-score < -2.5) were included in this study. Risk factors were: age, BMI, alcohol intake, corticosteroid therapy, hypogonadism, and chronic diseases. Transiliac bone biopsies were obtained and histomorphometry was done on an image analyzer; the following parameters were measured: cortical thickness (Ct.Th), trabecular bone volume (BV/TV), trabecular thickness (Tb.Th), separation (Tb.Sp) and number (Tb.N), interconnectivity Index (ICI), star volume of the bone marrow, and strut analysis with node and free-end count. The 50 men with two risk factors had a lower BMD, lower Ct.Th and a significant higher star volume than those with one factor or idiopathic osteoporosis. The 26 men with at least three risk factors, had a lower BMD, a reduction of BV/TV and Ct.Th and a marked disorganization of the trabecular network (increased Tb.Sp, ICI, star volume, and free-end to free-end struts). The prevalence of vertebral fractures was higher in these patients. When the main risk factor was considered, a marked decrease in trabecular bone connectivity was observed in hypogonadic men. In osteoporotic men, higher the number of risk factors, lower the connectivity of trabecular network and higher the vertebral fracture risk.

Bone Related Events in High Risk Prostate Cancer

PURPOSE

We provide recommendations for defining and treating bone related events in high risk prostate cancer.

MATERIALS AND METHODS

A focused literature review was done.

RESULTS

Men with prostate cancer often have osteoporosis and osteopenia even before initiating androgen deprivation therapy. After starting androgen deprivation therapy they experience accelerated bone loss. Bone mineral density is the most common tool to assess the degree of bone loss, although the use of bone turnover markers for this purpose is being actively explored. Bisphosphonates are effective for increasing bone mineral density and treating osteoporosis. The benefits derived from bisphosphonates should be weighed against the adverse effects, including the risk of osteonecrosis of the jaw. Treatment is indicated in patients with prostate cancer with osteoporosis and it may be considered in patients with osteopenia and/or additional risk factors. The time of initiation of therapy and duration of treatment have not been conclusively established.

CONCLUSIONS

Prolonged androgen deprivation therapy results in bone loss and it has a potential to impact quality of life. Additional research is needed to characterize patients who would benefit from therapy and optimize strategies to prevent osteoporosis.

Treatment-related osteoporosis in men with prostate cancer

The intended therapeutic effect of gonadotropin-releasing hormone (GnRH) agonists is hypogonadism, a major cause of acquired osteoporosis in men. Consistent with this observation, GnRH agonists increase bone turnover and decrease bone mineral density, a surrogate for fracture risk. Large claims-based analyses and other retrospective studies provide compelling evidence that GnRH agonists increase risk of clinical fractures. Estrogens play a central role in homeostasis of the normal male skeleton, and estrogen deficiency rather than testosterone deficiency seems to be primarily responsible for the adverse skeletal effects of GnRH agonists. In randomized controlled trials, bisphosphonates (pamidronate and zoledronic acid) and selective estrogen receptor modulators (raloxifene and toremifene) increased bone mineral density in GnRH agonist-treated men. Two ongoing large randomized placebo-controlled studies will prospectively define fracture outcomes in men with prostate cancer and assess the efficacy of novel pharmacologic interventions (AMG162, toremifene) during GnRH agonist treatment.

Prevention and management of osteoporosis in men receiving androgen deprivation therapy: a survey of urologists and radiation oncologists

OBJECTIVES

To determine the current practice of clinicians in the diagnosis and management of osteoporosis among men taking androgen deprivation therapy (ADT), because ADT leads to decreased bone mineral density (BMD) and fractures.

METHODS

We sent out a survey to Canadian urologists and radiation oncologists. The survey included questions about BMD testing, treatment practices, referral patterns, and risk of osteoporosis.

RESULTS

The surveys were returned by 170 of 294 respondents (response rate 58%). Few respondents would obtain a baseline BMD in patients starting ADT. Forty percent would order a repeat BMD test after starting ADT if the baseline BMD were normal or unknown, but more than two thirds would if the baseline BMD showed osteoporosis. In men with a normal BMD starting ADT, respondents recommended weight-bearing exercises (58%), calcium (50%), vitamin D (47%), and bisphosphonate (6%) supplements. In men with osteoporosis at baseline, the use of nonprescription therapies increased slightly and bisphosphonate use increased to 44%. If osteoporosis were diagnosed, 11% would treat the patient themselves. The estimated risk of developing osteoporosis within 1 year of starting ADT with a normal baseline BMD ranged from 0% to 90% (median 20%).

CONCLUSIONS

To our knowledge, this is the first survey of its kind. The key findings included that few physicians would order a baseline BMD test, would prescribe bisphosphonates for prevention but almost one half would consider bisphosphonates to treat established osteoporosis, and wide variations exist in the practice patterns and risk perception surrounding ADT-related osteoporosis. Evidence-based guidelines are needed to help physicians deal effectively with osteoporosis prevention and management among men taking ADT.

The role of bisphosphonates in preventing skeletal complications of hormonal therapy

Androgen deprivation therapy (ADT) is associated with a significant decrease in bone mineral density (BMD), and continued exposure seems to increase the risk of osteoporotic fracture in men who have prostate cancer treated with this strategy. Men who have prostate cancer may have low BMD before initiation of ADT. Bisphosphonates are pyrophosphate analogs that decrease bone resorption primarily through direct inhibition of osteoclast activity and proliferation. Several bisphosphonates have been evaluated in randomized clinical trials, and the cumulative data show that these medications increase or maintain BMD in men receiving ADT for prostate cancer. The effect on clinical fractures has not been assessed adequately, but bisphosphonates offer an important potential treatment modality to reduce the risk of osteoporotic fracture in this population of men.

Cancer-treatment-induced bone loss, part 1

PURPOSE

The pathophysiology, frequency, sequelae, diagnosis, and treatment of cancer-treatment-induced bone loss (CTIBL) are discussed.

SUMMARY

CTIBL is a long-term complication associated with cancer therapies that can directly or indirectly affect bone metabolism. Although CTIBL can occur in any patient receiving a cancer therapy known to cause bone loss, CTIBL is most common in patients with breast or prostate cancer who receive chemotherapy, hormone therapy, or surgical castration, as these can cause hypogonadism and induce bone loss. CTIBL causes bone fragility and an increased susceptibility to fractures; therefore, prevention, early diagnosis, and treatment of CTIBL are essential to decrease the risk of fracture. Bone loss occurs more rapidly and tends to be more severe in patients with CTIBL compared with those with normal age-related bone loss. Fractures of the hip, vertebra, and wrist are the fractures most commonly associated with bone loss. CTIBL is diagnosed by measuring bone mass using bone densitometry. Treatment of CTIBL consists of changing diet and lifestyle such as optimizing calcium and vitamin D intake, exercising, modifying behaviors known to increase the risk of CTIBL and pharmacologic therapy with hormone replacement therapy (HRT), selective estrogen-receptor modifiers (SERMs), calcitonin, or a bisphosphonate.

CONCLUSION

Early identification and treatment of CTIBL are essential to prevent fractures. Patients should be instructed to optimize calcium and vitamin D intake, exercise regularly, and modify lifestyle behaviors known to cause bone loss. Patients with CTIBL should be treated with an oral or i.v. bisphosphonate; SERMs or HRT may be an option in some patients if contraindications do not exist.

Transdermal estradiol improves bone density when used as single agent therapy for prostate cancer

PURPOSE

Current androgen deprivation therapies for men with prostate cancer cause accelerated osteoporosis and a significant risk of osteoporotic fracture. We have recently shown that transdermal estradiol is an effective alternative for such patients. Here we report the impact of transdermal estradiol therapy on the bone mineral density of men with prostate cancer.

MATERIALS AND METHODS

A total of 20 patients with newly diagnosed locally advanced or metastatic prostate cancer were treated with transdermal estradiol patches. Bone mineral density of the lumbar spine and the proximal femur was measured with dual-energy x-ray absorptiometry, and correlated with computerized tomography and isotope bone scan findings at 6-month intervals.

RESULTS

In all measured regions bone mineral density increased with time. By 1 year mean bone mineral density +/- SEM had increased by 3.60% +/- 1.6% in the lumbar spine (p = 0.055), 2.19% +/- 1.03% in the femoral neck (p = 0.055), 3.76% +/- 1.35% in the Ward's region (p = 0.008) and 1.90% +/- 0.85% in the total hip (p = 0.031), respectively. Of 12 osteoporotic sites 4 had improvement based on World Health Organization grading. All other sites improved toward a better classification.

CONCLUSIONS

Transdermal estradiol protects against bone loss in men with prostate cancer and may improve bone density in those at risk for osteoporotic fracture.

Toremifene--a promising therapy for the prevention of prostate cancer and complications of androgen deprivation therapy

Deregulation of the estrogen axis in humans prompts a series of tissue-specific events. In the breast and prostate, alterations in estrogen signalling lead to genotypic and phenotypic molecular alterations that result in dysplastic cellular appearance, deregulated cell growth and carcinoma. In bone, decreased estrogen leads to increased osteoclastogenesis and bone resorption, decreased bone mineral density and a significant fracture risk. Toremifene is a selective estrogen receptor modulator that exerts pharmacological activity in the breast, bone and prostate. An intense interest in developing this agent for prostate cancer chemoprevention is based on the reduction of premalignant and malignant prostate lesions in a transgenic model of prostate cancer. Biological and clinical activity was demonstrated in Phase II trials by the prevention of progression to prostate cancer in men with high-grade prostate intraepithelial neoplasia and through suppression of bone turnover biomarkers and increased bone mineral density in men on androgen deprivation therapy for prostate cancer.

Therapy Insight: osteoporosis during hormone therapy for prostate cancer

The intended therapeutic effect of gonadotropin-releasing-hormone (GnRH) agonists is hypogonadism, which is a leading cause of osteoporosis in men. Observations are consistent with this effect: GnRH agonists decrease bone mineral density and increase fracture risk in men with prostate cancer. Estrogens play a central role in homeostasis of the normal male skeleton and evidence suggests that estrogen deficiency is primarily responsible for the adverse skeletal effects of GnRH agonists. The mechanism of treatment-related bone loss involves acceleration of physiologic bone turnover. In small, randomized, controlled trials, bisphosphonates (pamidronate, zoledronic acid) and selective estrogen-receptor modulators (raloxifene, toremifene) increased bone mineral density in GnRH-agonist-treated men. Two ongoing large, randomized, placebo-controlled studies will prospectively define fracture outcomes in men with prostate cancer and assess the efficacy of novel pharmacologic interventions (AMG 162, toremifene) in GnRH-agonist-treated men.

Maintaining bone health in patients with prostate cancer

Loss of bone mineral density with androgen deprivation therapy (ADT) for prostate cancer is well recognised, with significant loss of bone mineral density (BMD) occurring within 12 months of starting therapy. With ADT, annual loss of BMD is about 2%-8% per year at the lumbar spine and 1.8%-6.5% at the hip; the loss appears to continue indefinitely while treatment continues, and there is no recovery after therapy is ceased. 19.4% of men surviving at least 5 years after diagnosis of prostate cancer have a fracture if treated with ADT compared with 12.6% of men not receiving ADT; this is equivalent to one additional fracture for every 28 men treated with ADT. Vitamin D deficiency exacerbates the development of osteoporosis, so vitamin D status should be evaluated before commencing ADT in men with prostate cancer. Treatment with bisphosphonates (zoledronate, pamidronate and alendronate) in men treated with ADT have been shown to prevent bone loss in prospective studies and to increase BMD in one randomised controlled trial; bisphosphonates have not been shown to prevent fractures in men with prostate cancer. Further prospective trials are required to assess the efficacy and cost-effectiveness of bisphosphonates in men with prostate cancer who require treatment with ADT. All doctors need to take an active role in monitoring bone health in patients with prostate cancer requiring ADT.

[Treatment options for hormone-refractory prostate cancer]

Surgical or medical androgen deprivation therapy in its multiple variants represents the standard therapeutic approach in the management of metastatic prostate cancer resulting in a primary response rate of about 90%. However, about 90% of the men treated will develop PSA progression within 3-4 years resulting in androgen-independent and later on hormone-refractory prostate cancer. Management of AIPCA and HRPCA still represents a therapeutic challenge despite the development of new and effective treatment options. PSA progression following primary ADT defines an androgen-refractory but still hormone-sensitive PCA which might respond to secondary hormonal manipulations such as antiandrogen withdrawal, addition of nonsteroidal antiandrogens, and administration of estrogens, ketoconazole and hydrocortisone, and somatostatin analogues. Secondary hormonal manipulations will result in a PSA decline >50% in about 60-80% of the patients with a mean duration of 7-17 months depending on the type of treatment. PSA progression following secondary endocrine treatment defines hormone-refractory prostate cancer (HRPCA) which might be treated by systemic chemotherapy. Based on the results of two prospective, randomized clinical phase III trials comparing docetaxel and mitoxantrone, docetaxel results in a statistically significant survival benefit of 2.5 months, a significantly higher PSA and pain response, and represents the treatment of choice in the management of HRPCA. Bisphosphonates such as zoledronate represent another cornerstone in the management of PSA-progressive PCA demonstrating a significant benefit with regard to the prevention of skeletal-related events. Furthermore, bisphosphonates might be indicated in the treatment of symptomatic bone pain as has been demonstrated for ibandronate and zoledronate. The current article critically reflects on the various therapeutic options in the management of PSA progression following primary androgen deprivation for advanced prostate cancer. The development, rationale, and results of systemic chemotherapy are discussed critically and a therapeutic algorithm is demonstrated.

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

PURPOSE

We assessed the relationship between GnRH agonists and the risk of clinical fractures in men with prostate cancer.

MATERIALS AND METHODS

Using a database of medical claims from 16 large American companies we identified a study group of 3,779 men with prostate cancer who received treatment with a GnRH agonist and a control group of 8,341 with prostate cancer who were not treated with a GnRH agonist. Men with 1 or more medical claims for bone metastases were excluded. The rates of any clinical fracture, hip fracture and vertebral fracture were compared between the groups.

RESULTS

The rate of any fracture was 7.91/100 vs 6.55/100 person-years at risk in men who received vs did not receive a GnRH agonist (relative risk 1.21, 95% CI 1.09 to 1.34). The rates of hip fracture (relative risk 1.76, 95% CI 1.33 to 2.33) and vertebral fracture (relative risk 1.18, 95% CI 0.94 to 1.48) were also higher in men who received a GnRH agonist. GnRH agonist treatment was independently associated with fracture risk on multivariate analyses.

CONCLUSIONS

GnRH agonists increase the risk of clinical fracture in men with prostate cancer.

Serum tartrate-resistant acid phosphatase 5b (TRACP 5b) as a marker of skeletal changes in prostate cancer

Skeletal metastases are a significant problem in prostate cancer (PC). The patients are also exposed to treatment-related skeletal changes. This cross-sectional study evaluated a marker of bone resorption, TRACP 5b in relation to the standard analyte total alkaline phosphatase (tALP) as a marker of skeletal changes. Serum levels of TRACP 5b, tALP and PSA were measured in 130 prostate cancer patients. Comparison was made between patients with (BM+, n = 25) and without (BM-, n = 105) skeletal metastases, and between those treated with (n = 64) or without (n = 66) androgen deprivation (AD). Sensitivities and specificities were calculated for each marker and diagnostic accuracy was evaluated by ROC curve analysis. ROC curves indicated the superior accuracy of tALP, whereas TRACP 5b and PSA were comparable. With tALP the best combination of sensitivity (96%) and specificity of (91%) was reached at a cut-off point 224 U/L, the corresponding values were for TRACP 5b sensitivity (76%), specificity (89%) with a cut-off point 4.89 U/L, and for PSA sensitivity (65%), specificity (81%) at 23 ng/L for skeletal metastases. Patients treated with AD showed with increasing duration an increase in TRACP 5b values. TRACP 5b was less specific than tALP as a marker of skeletal metastases. TRACP 5b may have a role in the diagnostics of skeletal changes in PC with a focus on treatment-related skeletal changes.

Gonadotropin-releasing hormone agonists and fracture risk: a claims-based cohort study of men with nonmetastatic prostate cancer

PURPOSE

Gonadotropin-releasing hormone (GnRH) agonists decrease bone mineral density, a surrogate for fracture risk, in men with prostate cancer. We conducted a claims-based cohort study to characterize the relationship between GnRH agonists and risk for clinical fractures in men with nonmetastatic prostate cancer.

PATIENTS AND METHODS

Using medical claims data from a 5% national random sample of Medicare beneficiaries, we identified a study group of men with nonmetastatic prostate cancer who initiated GnRH agonist treatment from 1992 to 1994 (n = 3,887). A comparison group of men with nonmetastatic prostate cancer who did not receive GnRH agonist treatment during the study period (n = 7,774) was matched for age, race, geographic location, and comorbidity. Clinical fractures were identified using inpatient, outpatient, and physician claims during 7 years of follow-up.

RESULTS

In men with nonmetastatic prostate cancer, GnRH agonists significantly increased fracture risk. The rate of any clinical fracture was 7.88 per 100 person-years at risk in men receiving a GnRH agonist compared with 6.51 per 100 person-years in matched controls (relative risk, 1.21; 95% CI, 1.14 to 1.29; P < .001). Rates of vertebral fractures (relative risk, 1.45; 95% CI, 1.19 to 1.75; P < .001) and hip/femur fractures (relative risk, 1.30; 95% CI, 1.10 to 1.53; P = .002) were also significantly higher in men who received a GnRH agonist. GnRH agonist treatment independently predicted fracture risk in multivariate analyses. Longer duration of treatment conferred greater fracture risk.

CONCLUSION

GnRH agonists significantly increase risk for any clinical fracture, hip fractures, and vertebral fractures in men with prostate cancer.

Therapie des hormonrefraktären Prostatakarzinoms

PSA-progression following primary ADT defines an androgen-refractory but still hormone sensitive PCA which might respond to secondary hormonal manipulations. Secondary hormonal manipulations will result in a PSA decline >50% in about 60-80% of the patients with a mean duration of 7-17 months depending on the type of treatment. PSA-progression following secondary endocrine treatment defines hormone-refractory prostate cancer (HRPCA) which might be treated by systemic chemotherapy. Based on the results of 2 prospective, randomized clinical phase-III trials comparing docetaxel and mitoxantrone, docetaxel results in a statistically significant survival benefit of 2.5 months, a significantly higher PSA- and pain response and represents the treatment of choice in the management of HRPCA. Bisphosphonates such as zoledronate represent another cornerstone in the management of PSA-progressive PCA demonstrating a significant benefit with regard to the prevention of skeletal related events. Furthermore, bisphosphonates might be indicated in the treatment of symptomatic bone pain. The current article critically reflects the various therapeutic options in the management of PSA progression following primary androgen deprivation for advanced prostate cancer.

Bone mineral density changes on androgen deprivation therapy for prostate cancer and response to antiresorptive therapy

Androgen deprivation therapy improves survival of patients with prostate cancer and leads to hypogonadal state. Gonadal hormones are essential for skeletal integrity and hypogonadism constitutes a major risk factor for osteoporosis. To examine the bone loss secondary to androgen deprivation therapy, we reviewed the bone mineral density (BMD) studies of 152 patients with prostate cancer with mean duration of androgen deprivation therapy of 58 months. Among them 55 subjects had follow-up BMD measurement at 12-15 months with 39 of them on antiresorptive therapy. Osteoporosis was noted at least at one site in 92 (60.5%), among which 74 (48.7%) had changes at hip with the more prominent changes at ward's triangle, 18 (11.8%) at other sites. Osteopenia was present in 37 (24%) and only 17 (11%) were normal. The duration of antiandrogen therapy did not correlate with the degree of bone loss. Significant in improvement in the BMD is noted at 12-15 month follow-up on antiresorptive therapy. We conclude that men treated with androgen deprivation therapy are at risk for bone loss and should have BMD measured at the time of initiation of androgen deprivation therapy and periodically.

Risks and benefits of hormonal manipulation as monotherapy or adjuvant treatment in localised prostate cancer

A round table meeting was held to discuss the role of hormonal therapy in localised prostate cancer. The findings of the group were that immediate hormonal therapy does not provide an overall survival advantage in localised and locally advanced prostate cancer. Bicalutamide can prolong disease free survival in patients with locally advanced prostate cancer, however it is important to underline that at this time it has not been shown to influence disease specific nor overall survival. It remains also unproven that early treatment is superior to treatment at progression. However, a trend towards decreased survival with bicalutamide was observed in low risk patients such as those with localised disease. In patients receiving bicalutamide, there were increased cardiovascular side-effects, in addition to the high incidence of gynaecomastia. Early hormonal therapy has to be balanced against such side-effects and the inevitable appearance of hormone refractory disease in patients who progress after hormonal therapy. Consequently, patients with localised, low risk disease are not considered appropriate candidates for hormonal therapy used either as mono-therapy or in the adjuvant setting.

Das Nachsorgeprinzip beim metastasierten Prostatakarzinom

For advanced prostate cancer - not including intermittent strategies - the patient is in continual treatment. The effect of the therapy must be controlled so that its failure can be determined as soon as possible and a new regimen started. As in most cases the progression of the disease can not be stopped, the aim of the therapy is to provide the patient with the best possible quality of life. In order to carry out therapy, if possible in the patient's usual environment, supportive therapies should be used, such as compensation for anaemia or pain therapy as required. Skeletal complications can be prophylactically treated by the use of biphosphonates.

High dose estrogen treatment increases bone mineral density in male-to-female transsexuals receiving gonadotropin-releasing hormone agonist in the absence of testosterone

OBJECTIVE

To study the effect of estrogen (E) on the male skeleton in the absence of testosterone (T).

DESIGN

Retrospective analyses of 40 middle-aged transsexuals treated with subcutaneous injections of gonadotropin-releasing hormone agonist every 4 weeks and oral 17-beta-estradiol-valerat 6 mg/day over two years until reassignment surgery.

METHODS

The bone mineral density (BMD) in the femoral neck and lumbar spine (L2-L4) was measured with dual-energy X-ray absorptiometry at the beginning of cross-sex hormone treatment, after 12 and 24 months, and serum T, E, sex hormone-binding globulin (SHBG), calcitonin (CAL), osteocalcin (OSC), and urinary free deoxypyridinoline (DPD) were measured.

RESULTS

After 12 months, a significant increase in BMD in the lumbar spine from 1.2 to 1.234 g/cm2 and after 24 months to 1.274 g/cm2 was observed. There was a significant increase in BMD in the femoral neck area from 1.068 to 1.109 g/cm(2) after 24 months. There was a significant decrease in serum T levels from 18.65 to 0.57 nmol/l after 12 months, and to 0.62 nmol/l after 24 months, a significant increase in SHBG levels from 50.09 to 125 nmol/l after 12 months, and to 130 nmol/l after 24 months, and a significant increase in serum E levels from 73.42 to 881.6 pmol/l after 12 months, and to 923.62 pmol/l after 24 months of cross-sex hormone treatment. Serum levels of CAL, OSC and urinary DPD were unchanged.

CONCLUSION

We conclude that high dose E treatment is able to increase BMD significantly in the femoral neck and lumbar spine independently of serum T levels in middle-aged men. There is no risk of osteoporosis developing in male-to-female transsexuals receiving GnRHa when there is an adequate E substitution.

Fracture risk in patients with prostate cancer on androgen deprivation therapy

Although a decrease in bone mass is a well-known side effect of hormone therapy for prostate carcinoma, its clinical significance is unclear, as there is only scanty information about the incidence of fractures. Therefore, the aim of this study was to determine the risk of non-metastatic fractures in patients with prostate cancer undergoing androgen deprivation therapy. We performed a retrospective cohort study that comprised 288 patients with cancer who were subjected to androgen deprivation therapy (ADT). All were given LHRH agonists, and most of them also received peripheral androgen receptor blockers. The results were compared with a control group of 300 men that were not receiving ADT. The incidence rates of peripheral and vertebral fractures in the group of men on ADT were 1.9 and 0.8 per 100 patient-years, respectively. Incidence rates in the control group were 0.5 and 0.2, respectively. In the whole study group, 35 patients had at least one fracture during follow-up (25 on ADT, ten controls). Thus, the number of patients with at least one fracture was significantly higher in the group on ADT (P = 0.001 by the log-rank test). The unadjusted risk ratio was 4.2 (CI 2.0-8.9). A similar value (risk ratio 3.6; CI 1.6-7.7, P = 0.001) was found after it was adjusted for other factors, such as age or prior fractures. Therefore, ADT is associated with a fourfold increase in the incidence rate of both peripheral and vertebral fractures. Although the absolute incidence remains relatively small, preventive measures should be considered for high-risk patients.

Preventing and treating the complications of hormone therapy

Hormonal manipulation in the form of androgen-deprivation therapy for prostate cancer was introduced by Huggins and Hodges in 1941 and resulted in a Nobel Prize in 1966. Hormonal therapy initially had been used in metastatic prostate cancer, but the indications have been expanded including failed local therapy, locally advanced prostate cancer, and neoadjuvant or adjuvant therapy in high-risk localized prostate cancer. In view of the magnitude of the problem of prostate cancer and relatively frequent use of hormonal manipulation, it is important for clinicians to be aware of common side effects, prevention, and treatment to improve quality of life and reduce morbidity and mortality in patients with prostate cancer. This review focuses on the common side effects of hormonal treatment such as osteoporosis, anemia, hot flashes, erectile dysfunction, muscle wasting, gynecomastia, decline in cognitive function, depression, increase in body fat and metabolic changes, and their prevention and treatment.

Preventing Bone Loss During Androgen Deprivation Therapy for Prostate Cancer: Early Experience with Neridronate

OBJECTIVE

Androgen-deprivation therapy (ADT) is the usual treatment for locally advanced or metastatic prostate cancer. Osteoporosis is a common complication of ADT. The aim of our study was to evaluate the efficacy of neridronate, a relatively new bisphosphonate to prevent bone loss during androgen ablation.

METHODS

Sixty patients with prostate cancer and osteoporosis were enrolled and randomly assigned to 2 different treatment regimes: group A (30 patients) treated with maximum androgenic blockage (MAB), and group B (30 patients) treated with bicalutamide 150 mg. Each group was divided in 2 subgroups A1-A2 and B1-B2. All patients received calcium and cholecalciferol supplements (500 mg of elemental calcium and 400 IU cholecalciferol) daily. The A2 and B2 subgroups were also treated with neridronate (25 mg intramuscular monthly). Lumbar and femoral bone mineral density (BMD) was evaluated by dualenergy X-ray absorptiometry (DXA), both at baseline and after one year of treatment. Deoxypyridinoline (DPD) and bone-alkaline phosphatase (B-ALP) were determined at the beginning, midstudy and at the end.

RESULTS

Patients treated only with calcium and cholecalciferol (A1, B1 subgroups) showed a marked bone loss after 6, and 12 months, with increased levels of DPD and BALP, compared to baseline values. Patients treated with neridronate (A2 et B2 subgroups) showed unchanged levels of these markers. After one year of treatment, lumbar and total hip BMD decreased significantly in patients treated only with calcium and cholecalciferol (A1 subgroup: -4.9% and -1.9% respectively). BMD did not change significantly at any site in patients treated also with neridronate (A2 subgroup: +1% and +0.8% respectively). Lumbar and total hip BMD did not change significantly (-1.5% and -1% respectively) in B1 subgroup. In B2 subgroup an important increase in lumbar spine and the total hip BMD was shown (+2.5% and 1.6% respectively). No relevant side effects were recorded during our study.

CONCLUSION

In conclusion, neridronate is an effective and safe treatment in preventing bone loss in men receiving ADT for prostate cancer.

Risk of fracture after androgen deprivation for prostate cancer

BACKGROUND

The use of androgen-deprivation therapy for prostate cancer has increased substantially over the past 15 years. This treatment is associated with a loss of bone-mineral density, but the risk of fracture after androgen-deprivation therapy has not been well studied.

METHODS

We studied the records of 50,613 men who were listed in the linked database of the Surveillance, Epidemiology, and End Results program and Medicare as having received a diagnosis of prostate cancer in the period from 1992 through 1997. The primary outcomes were the occurrence of any fracture and the occurrence of a fracture resulting in hospitalization. Cox proportional-hazards analyses were adjusted for characteristics of the patients and the cancer, other cancer treatment received, and the occurrence of a fracture or the diagnosis of osteoporosis during the 12 months preceding the diagnosis of cancer.

RESULTS

Of men surviving at least five years after diagnosis, 19.4 percent of those who received androgen-deprivation therapy had a fracture, as compared with 12.6 percent of those not receiving androgen-deprivation therapy (P<0.001). In the Cox proportional-hazards analyses, adjusted for characteristics of the patient and the tumor, there was a statistically significant relation between the number of doses of gonadotropin-releasing hormone received during the 12 months after diagnosis and the subsequent risk of fracture.

CONCLUSIONS

Androgen-deprivation therapy for prostate cancer increases the risk of fracture.

Epidemiology of male osteoporosis and prostate cancer

PURPOSE OF REVIEW

In this review, we will discuss the increasing importance of male osteoporosis, risk factors for the disease, its relationship to prostate cancer and androgen deprivation treatment modalities for prostate cancer, and recent trials describing therapeutic intervention.

RECENT FINDINGS

Osteoporosis has become an increasingly important problem in men's health, accounting for significant morbidity in the aging United States male population. Hypogonadism is a major risk factor. Patients treated with androgen deprivation therapy for advanced or metastatic prostate cancer are at risk for both hypogonadism and osteoporosis. These patients may suffer additional morbidity from decreased bone mineralization, such as skeletal fracture. There is a direct association with fracture and decreased quality of life and increased mortality.

SUMMARY

Male osteoporosis is an important clinical entity, particularly in aging men and in men with prostate cancer treated with androgen deprivation therapy. No screening recommendations currently exist; however, patients at risk for decreased bone mineralization should be screened and treated to prevent consequent fractures.

Factors affecting bone mineral density in patients with prostate carcinoma before and after orchidectomy

BACKGROUND

Orchidectomy is an accepted form of androgen-deprivation therapy (ADT) for prostate carcinoma. Osteoporosis is common in elderly individuals and is accelerated by ADT. The authors studied changes in bone mineral density (BMD) after ADT and factors that affected those changes.

METHODS

Fifty patients with prostatic adenocarcinoma who opted to undergo orchidectomy were studied prospectively. All patients completed 6 months of follow-up, and 20 of those patients completed 12 months of follow-up. Patients' age, weight, height, body mass index (BMI), physical activity, addiction (smoking, alcohol), dietary calcium intake, and lactose tolerance status were noted. Lumbar spinal (L1-L3) trabecular BMD was measured with quantitative computed tomography (QCT) at baseline and every 6 months for 1 year and was compared with preoperative values. The effects of various patient characteristics on preoperative BMD and changes in BMD also were analyzed.

RESULTS

The mean +/- standard deviation (SD) age of the patients was 69.5 +/- 8.1 years, BMI was 23.5 +/- 3.9 kg/m2, dietary calcium intake was 1066.1 +/- 443.3 mg per day. Thirty-eight percent of patients were lactose intolerant. Sixty-two percent of patients were in the light weight-bearing activity group. The mean +/- SD preoperative BMD was 119.2 +/- 34.9 mg/cc, with T-scores of - 1.77 +/- 1.22 and Z-scores of 0.43 +/- 1.27. A decrease in BMD during the first 6 months ( approximately 13%) was statistically significant (P = 0.0001) and continued further during next 6 months (BMD loss of approximately 18% at 12 months). Patients with osteoporosis, as defined by T-scores < or = - 2.5, increased from 24% at baseline to 48% at 6 months. Nonsmokers, nonalcoholics, patients with higher physical activity, and patients with a BMI > 25 kg/m2 had statistically significant higher BMD compared with their counterparts (P < 0.05). Body weight < 60 kg and BMI < 25 kg/m2 were significant risk factors for loss of BMD (P < 0.05). Dietary calcium had a discernible but statistically insignificant effect on BMD (P = 0.16). Lactose intolerance had no significant effect on BMD or bone loss.

CONCLUSIONS

Osteoporosis was common in the population affected by prostate carcinoma. Orchidectomy led to accelerated bone loss. Periodic measurement of BMD after ADT would help in the early detection of osteoporosis. Maintenance of high BMI, weight-bearing physical activity, avoidance of alcohol and smoking, and possibly high dietary calcium intake help in maintaining bone mass.

Contribution of androgen deprivation therapy to elevated osteoclast activity in men with metastatic prostate cancer

PURPOSE

Biochemical markers of both osteoblast and osteoclast activity are elevated in men with osteoblastic metastases from prostate cancer. Androgen deprivation therapy (ADT), the mainstay of therapy for advanced prostate cancer, increases markers of osteoblast and osteoclast activity, even in the absence of bone metastases. Little is known about the relative contributions of ADT and skeletal metastases to elevated bone turnover in men with prostate cancer.

EXPERIMENTAL DESIGN

To evaluate the relative contributions of ADT and skeletal metastases to osteoblast and osteoclast activity, we performed a cross-sectional study in three groups of men with advanced prostate cancer: (a) hormone-naïve men without bone metastases; (b) castrate men without bone metastases; and (c) castrate men with bone metastases. The primary study end points were serum levels of bone-specific alkaline phosphatase (BSAP), a marker of osteoblast activity, and N-telopeptide (NTX), a marker of osteoclast activity.

RESULTS

Serum levels of both BSAP and NTX were significantly higher in groups of castrate men (groups 2 and 3) than in hormone-naïve men (group 1; P < 0.01 for all comparisons). Among castrate men, serum BSAP was significantly higher in men with bone metastases than in men without bone metastases (P = 0.01). In contrast, serum levels of NTX were similar in groups 2 and 3 (P = 0.33).

CONCLUSIONS

The unintended effects of ADT on the skeleton are sufficient to explain increased osteoclast activity in castrate men with bone metastases. These results may have important implications for the optimal timing and schedule of osteoclast-targeted therapy in men with advanced prostate cancer.

Osteoporosis and obesity in men receiving hormone therapy for prostate cancer

PURPOSE

A presentation on osteoporosis, obesity and obesity related disease at the Conference on Innovations and Challenges in Prostate Cancer: Prevention, Detection and Treatment is summarized.

MATERIALS AND METHODS

A focused literature review was done.

RESULTS

Gonadotropin-releasing hormone (GnRH) agonists decrease bone mineral density and increase fracture risk. GnRH agonists also increase weight and fat mass, and decrease lean body mass. Treatment related changes in body composition may contribute to fatigue and fracture risk. The phenotype of men with GnRH agonist shares some features with the insulin resistance syndrome, raising the possibility that GnRH may also increase the risk of diabetes mellitus and cardiovascular disease.

CONCLUSIONS

The routine use of GnRH agonists in men with long life expectancy increases the importance of understanding and preventing the unintended adverse effects of treatment. Some adverse effects have the potential to impact not only quality of life, but also noncancer mortality. Additional research is needed to characterize better the unintended effects of androgen deprivation therapy and develop optimal strategies to prevent osteoporosis, obesity and obesity related disease.

HIP FRACTURES IN MEN WITH PROSTATE CANCER TREATED WITH ORCHIECTOMY

PURPOSE

Androgen deprivation therapy increases the risk of osteoporosis related fractures. This issue is of increasing importance in men with prostate cancer as increasingly more undergo androgen deprivation therapy and therapy is administered sooner following diagnosis. Data directly addressing the long-term fracture risk in men diagnosed with prostate cancer are limited.

MATERIALS AND METHODS

Using population based registries in Sweden we studied the incidence of hip fractures in 17,731 men diagnosed with prostate cancer from 1964 to 1996 who were treated with bilateral orchiectomy within 6 months of diagnosis. The fracture incidence was compared to the incidence in 43,230 men diagnosed with prostate cancer but not treated with orchiectomy and in 362,354 of similar age who were randomly selected from the general population.

RESULTS

Men treated with orchiectomy were at increased risk for hip fracture. The estimated relative risk comparing men who underwent orchiectomy to population controls was 2.11 (95% CI 1.94 to 2.29) for femoral neck fractures and 2.16 (95% CI 1.97 to 2.36) for intertrochanter fractures. An increased risk of hip fracture was observed as early as 6 months after orchiectomy and the relative risk remained fairly constant up to 15 years following orchiectomy.

CONCLUSIONS

Hip fracture risk increases almost immediately following orchiectomy and the excess risk persists for at least 15 years. This side effect should be considered when assessing the merits of androgen deprivation therapy, particularly in symptom-free men diagnosed with localized prostate cancer. Measures to prevent osteoporosis should be considered in men undergoing androgen deprivation therapy.

Self‐reported health and use of health care services in long‐term cancer survivors

Owing to an increasing number of long-term cancer survivors, the use of health care services and somatic health problems were compared between cancer survivors and a noncancer population. Data from the Nord-Trondelag Health Survey 2 (HUNT 2, 1995-1997) was merged with the Cancer Registry of Norway. Six cancer subgroups were constructed with diagnosis 5 years prior HUNT 2: testicular cancer (n= 59), colorectal cancer (n= 175), prostate cancer (n= 87), breast cancer (n= 258), gynaecological cancer (n= 153) and lymphoma/leukaemia (n= 83). For each cancer survivor 3 matched noncancer controls were selected from the HUNT 2 survey. The prevalence of common health problems, use of health care services and unfavourably life style parameters were compared between the 2 groups. Cancer survivors used health care services and received social welfare benefits more often than the controls. There was an increased risk of perceiving poor health after a history of cancer. Common health problems and/or unfavourable life style parameters could not explain poor health or the increased use of health care services among cancer survivors. Further studies are needed to investigate the reasons for increased use of health care services and perceived poor health in cancer survivors.

Neridronate prevents bone loss in patients receiving androgen deprivation therapy for prostate cancer

Today, androgen deprivation therapy is a cornerstone of treatment for advanced prostate cancer, although it presents important complications such as osteoporosis. Neridronate, a relatively new bisphosphonate, is able to prevent bone loss in patients with prostate cancer during androgen ablation.

INTRODUCTION

Androgen-deprivation therapy (ADT) is a cornerstone of treatment for advanced prostate cancer. This therapy has iatrogenic complications, such as osteoporosis. The aim of our study was to evaluate the efficacy of neridronate, a relatively new bisphosphonate, to prevent bone loss during androgen ablation.

MATERIALS AND METHODS

Forty-eight osteoporotic patients with prostate cancer, treated with 3-month depot triptorelina, were enrolled and randomly assigned to two different treatment groups: group A (n = 24) was treated with a daily calcium and cholecalciferol supplement (500 mg of elemental calcium and 400 IU cholecalciferol), and group B (n = 24) received in addition to the same daily calcium and cholecalciferol supplement, 25 mg of neridronate given intramuscularly every month. All patients also received bicalutamide for 4 weeks. Lumbar and femoral BMD was evaluated by DXA at baseline and after 1 year of therapy; moreover, deoxypyridinoline (DPD) and bone alkaline phosphatase (BALP) were determined at the beginning, midway through, and at the end of the study.

RESULTS

After 6 and 12 months, whereas patients treated only with calcium and cholecalciferol (group A) showed a marked bone loss, with increased levels of DPD and BALP compared with baseline values, patients treated also with neridronate (group B) had substantially unchanged levels of these markers. After 1 year of treatment, lumbar and total hip BMD decreased significantly in patients treated only with calcium and cholecalciferol (group A), whereas it did not change significantly at any skeletal site in patients treated also with neridronate (group B). No relevant side effects were recorded during our study.

CONCLUSIONS

Neridronate is an effective treatment in preventing bone loss in the hip and lumbar spine in men receiving ADT for prostate cancer.

Bicalutamide monotherapy versus leuprolide monotherapy for prostate cancer: effects on bone mineral density and body composition

PURPOSE

Gonadotropin-releasing hormone agonists decrease bone mineral density, lean mass, and muscle size and increase fat mass in men with prostate cancer. Less is known about the effects of bicalutamide monotherapy on bone mineral density and body composition.

PATIENTS AND METHODS

In a 12-month, open-label study, we randomly assigned 52 men with prostate cancer and no bone metastases to receive either leuprolide or bicalutamide (150 mg by mouth daily). Bone mineral density and body composition were measured by dual energy x-ray absorptiometry and quantitative computed tomography.

RESULTS

Mean (+/- standard error) bone mineral density of the posterior-anterior lumbar spine decreased by 2.5% +/- 0.5% in the leuprolide group and increased by 2.5 +/- 0.5 in the bicalutamide group from baseline to 12 months (P <.001). Mean changes in bone mineral density of the total body, total hip, femoral neck, and trabecular bone of the lumbar spine also differed significantly between groups (P < or =.003 for each comparison). Fat mass increased by 11.1% +/- 1.3% in the leuprolide group and by 6.4% +/- 1.1% in the bicalutamide group (P =.01). Changes in lean mass, muscle size, and muscle strength were similar between the groups. Breast tenderness and enlargement were more common in the bicalutamide group than in the leuprolide group. Fatigue, loss of sexual interest, and vasomotor flushing were less common in the bicalutamide group than in the leuprolide group.

CONCLUSION

In men with prostate cancer, bicalutamide monotherapy increases bone mineral density, lessens fat accumulation, and has fewer bothersome side effects than treatment with a gonadotropin-releasing hormone agonist.

Osteoporosis and spinal fractures in men with prostate cancer: risk factors and effects of androgen deprivation therapy

PURPOSE

We determined the risk factors for osteoporosis and spinal fractures in men with prostate cancer receiving androgen deprivation therapy.

MATERIALS AND METHODS

We performed a retrospective analysis of 87 consecutive men with prostate cancer receiving androgen deprivation therapy referred for evaluation of osteoporosis. Data were comprised of lateral thoracolumbar radiographs, bone densitometry, serum biochemistry and a detailed assessment of osteoporotic risk factors. Multivariate regression analysis was used to determine the major risk factors for osteoporosis and spinal fractures.

RESULTS

There were 38 (44%) men who were 74.5 years old with radiographic evidence of spinal fractures. They had an initial mean prostate specific antigen of 52.8 ng/ml and had received androgen deprivation therapy for a mean of 39.6 months (95% confidence interval 28.7 to 50.4). Mean spinal (quantitative computerized tomography t-score -4.2) and femoral neck bone mineral densities (dual energy x-ray absorptiometry t-score -2.1) were significantly lower than in men without spinal fractures (p < 0.001 for all measurements). In the regression analysis the duration of androgen deprivation therapy (p = 0.002), serum 25-hydroxyvitamin D levels (p = 0.003) and a history of alcohol excess (defined as more than 4 standard drinks daily, p = 0.04) were the main determinants of spinal fractures.

CONCLUSIONS

Prolonged androgen deprivation therapy, low serum 25-hydroxyvitamin D levels and a history of alcohol excess are important risk factors for osteoporosis and spinal fractures in men with prostate cancer.

Preventing male osteoporosis: prevalence, risks, diagnosis and imaging tests

There is no universal definition of an osteoporotic fracture. Fractures of the vertebra, hip, and forearm generally are considered osteoporotic fractures. There is an increasing recognition, however, that osteoporosis can lead to fractures at other anatomic sites, including the ribs, humerus, tibia, pelvis, and femur. Excluding these types of fractures could underestimate the total cost and impact of osteoporosis. There are a variety of risk factors for osteoporosis and fracture, but several methods can quantify a patient's risk, and these tools are valuable in guiding clinicians in effective intervention. The author hopes this brief review provides clinicians with an introduction and overview of osteoporosis and its risk factors, screening methods, and procedures. The field of urology is constantly evolving, with a growing need for clinicians to become more knowledgeable about preventive medicine. This and other articles should provide a good foundation for clinicians to alter the increasing prevalence of a medical condition that is one of the most preventable causes of morbidity and mortality in men.

The impact of osteoporosis in men treated for prostate cancer

Prostate cancer patients are at significant risk for SREs, with up to 50% of androgen-insensitive patients experiencing an SRE at 24 months. The risk increases with the duration and type of cancer treatment. SREs decrease HRQOL, increase the cost of care, and are associated negatively with overall survival. Screening men at greatest risk (slender white men and men with hormone refractory disease or metastatic disease) with BMD measurements, and initiating empiric therapy (vitamin D3, calcium, parenteral estrogens, bisphosphates) may be warranted.

Understanding treatments for bone loss and bone metastases in patients with prostate cancer: a practical review and guide for the clinician

Prostate cancer patients are at risk for developing bone loss and bone metastases. Clinicians prescribing ADT should appreciate the potential effects of ADT on BMD as well as the morbidity and mortality that can result from osteoporotic fractures. Measures to address the evaluation of patients and when to treat patients with significant bone loss have been discussed. Bisphosphonates effectively prevent loss of BMD in prostate cancer patients. Treatment of prostate cancer patients with established bone metastases with zoledronic acid should be considered strongly based on the results of the Saad study and other studies of patients with bone metastases with other malignancies. Zoledronic acid is approved by the US FDA for use in men with metastatic hormone-refractory prostate cancer and in the European Union for any patient with bone metastases, including prostate cancer patients,because of the beneficial impact of zoledronic acid on skeletal-related events. There is no validated method to determine which patients might benefit most from bisphosphonate therapy in this setting. Many questions about the use of bisphosphonate therapy in men with prostate cancer must be addressed, both in terms of the use in bone loss and bone metastases. These questions include: What is the optimal timing of therapy? Which bisphosphonate is best? What is the best dose and dose schedule? Do bisphosphonates effectively decrease skeletal fracture rates in patients with osteoporosis? How long should patients receive therapy? Are bisphosphonate "holidays" warranted? What are the long-term skeletal and renal toxicities? Is there a role for sequencing bisphosphonate therapy either before or after chemotherapy? Is bisphosphonate therapy synergistic with certain chemotherapy or other bone-targeted therapies? Which patients are the most likely to benefit from bisphosphonate therapy? What are clinically significant endpoints of bisphosphonate trials in patients with metastatic disease? Does inhibiting bone turnover also inhibit formation of bone metastases? Preliminary work in these areas has been completed, but more questions than answers are available. Given the rising costs of health care, it is imperative that these questions be addressed to best use the health care dollar while offering high-risk patients the best available therapy. At present, no data suggest that bisphosphonates should be used routinely to prevent BMD loss in men with normal BMD or to prevent the development of bone metastases in men with biochemical relapse. Continuing trials may give us guidance in the future.

Effects of gonadotropin-releasing hormone agonists on bone metabolism markers and bone mineral density in patients with prostate cancer

OBJECTIVES

To better understand bone metabolism and predict bone loss in treatment using gonadotropin-releasing hormone agonist for patients with prostate cancer.

METHODS

The changes in bone mineral density and blood levels of bone metabolism markers and the level of pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen, a specific marker of bone resorption, and carboxy-terminal pro-peptide of human type I procollagen, a specific marker of bone formation, were examined in 27 consecutive patients with prostate cancer without bone metastasis.

RESULTS

After 2 years of gonadotropin-releasing hormone treatment, the bone mineral density was significantly lower (median 0.937 g/cm2) than before treatment. Pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen began to increase significantly 6 months after the start of treatment (3.0 to 8.3 ng/mL, median 4.6, at baseline versus 3.4 to 8.2 ng/mL, median 5.2, after 6 months). Carboxy-terminal pro-peptide of human type I procollagen began to show a significant rise 1 year after the start of treatment (from 72.8 to 221.5 ng/mL, median 102.0, at baseline to 82.7 to 293.4 ng/mL, median 132.0, at 1 year).

CONCLUSIONS

Functional coupling between bone resorption and formation was noted, and a decrease in bone mass, even in men, owing to androgen deficiency, was biochemically demonstrated. Fluctuations in these two bone metabolism markers preceded the decrease of bone mineral density. Therefore, these markers might be a predictor of bone loss.