Cardiovascular mortality after androgen deprivation therapy for locally advanced prostate cancer: RTOG 85-31

External irradiation with or without long-term androgen suppression for prostate cancer with high metastatic risk: 10-year results of an EORTC randomised study

BACKGROUND

We did a randomised phase 3 trial assessing the benefit of addition of long-term androgen suppression with a luteinising-hormone-releasing hormone (LHRH) agonist to external irradiation in patients with prostate cancer with high metastatic risk. In this report, we present the 10-year results.

METHODS

For this open-label randomised trial, eligible patients were younger than 80 years and had newly diagnosed histologically proven T1-2 prostatic adenocarcinoma with WHO histological grade 3 or T3-4 prostatic adenocarcinoma of any histological grade, and a WHO performance status of 0-2. Patients were randomly assigned (1:1) to receive radiotherapy alone or radiotherapy plus immediate androgen suppression. Treatment allocation was open label and used a minimisation algorithm with institution, clinical stage of the disease, results of pelvic-lymph-node dissection, and irradiation fields extension as minimisation factors. Patients were irradiated externally, once a day, 5 days a week, for 7 weeks to a total dose of 50 Gy to the whole pelvis, with an additional 20 Gy to the prostate and seminal vesicles. The LHRH agonist, goserelin acetate (3·6 mg subcutaneously every 4 weeks), was started on the first day of irradiation and continued for 3 years; cyproterone acetate (50 mg orally three times a day) was given for 1 month starting a week before the first goserelin injection. The primary endpoint was clinical disease-free survival. Analysis was by intention to treat. The trial is registered at ClinicalTrials.gov, number NCT00849082.

FINDINGS

Between May 22, 1987, and Oct 31, 1995, 415 patients were randomly assigned to treatment groups and were included in the analysis (208 radiotherapy alone, 207 combined treatment). Median follow-up was 9·1 years (IQR 5·1-12·6). 10-year clinical disease-free survival was 22·7% (95% CI 16·3-29·7) in the radiotherapy-alone group and 47·7% (39·0-56·0) in the combined treatment group (hazard ratio [HR] 0·42, 95% CI 0·33-0·55, p<0·0001). 10-year overall survival was 39·8% (95% CI 31·9-47·5) in patients receiving radiotherapy alone and 58·1% (49·2-66·0) in those allocated combined treatment (HR 0·60, 95% CI 0·45-0·80, p=0·0004), and 10-year prostate-cancer mortality was 30·4% (95% CI 23·2-37·5) and 10·3% (5·1-15·4), respectively (HR 0·38, 95% CI 0·24-0·60, p<0·0001). No significant difference in cardiovascular mortality was noted between treatment groups both in patients who had cardiovascular problems at study entry (eight of 53 patients in the combined treatment group had a cardiovascular-related cause of death vs 11 of 63 in the radiotherapy group; p=0·60) and in those who did not (14 of 154 vs six of 145; p=0·25). Two fractures were reported in patients allocated combined treatment.

INTERPRETATION

In patients with prostate cancer with high metastatic risk, immediate androgen suppression with an LHRH agonist given during and for 3 years after external irradiation improves 10-year disease-free and overall survival without increasing late cardiovascular toxicity.

A natural history of weight change in men with prostate cancer on androgen-deprivation therapy (ADT): results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database

OBJECTIVES

• To better understand the natural history of weight change with androgen-deprivation therapy (ADT), we investigated the effect of ADT on body weight among men from the Shared Equal Access Regional Cancer Hospital (SEARCH) database. • Men undergoing ADT lose lean muscle but gain fat mass, contributing to an overall gain in weight.

PATIENTS AND METHODS

• We identified 132 men in SEARCH who received ADT after radical prostatectomy. • 'Weight change' was defined as the difference in weight before starting ADT (6 months before ADT) and the on-ADT weight (between 6 and 18 months after starting ADT). • In a subanalysis, baseline characteristics of weight-gainers and -losers were analysed using univariate and multivariate analysis to test association with weight change.

RESULTS

• In all, 92 men (70%) gained weight, and 40 (30%) either lost or maintained a stable weight. • On average, weight on ADT was 2.2 kg higher than the weight before ADT, with the mean change for weight-gainers and -losers being +4.2 kg and -2.4 kg, respectively. • This compared with no significant weight change in the year before starting ADT (paired t-test, change -0.7 kg, P= 0.19) or in the second year on ADT (paired t-test, change -0.5 kg, P= 0.46) for 84 men in whom these additional weight values were recorded. • There was no significant association between any of the features examined and weight change on univariate and multivariate analysis.

CONCLUSION

• In this longitudinal study, ADT was accompanied by significant weight gain (+2.2 kg). This change occurred primarily in the first year of therapy, with men neither losing nor gaining additional weight thereafter.

Cardiac and cognitive effects of androgen deprivation therapy: are they real?

With androgen deprivation therapy being used ever earlier and longer in the course of prostate cancer, concerns have emerged about a variety of adverse effects, including cardiovascular disease and cognitive dysfunction. Conflicting data in both areas have led to controversy and confusion. Here, we review published data in an attempt to clarify those issues.

Metabolic and cardiovascular risks of androgen-deprivation therapy for prostate cancer

Androgen-deprivation therapy is frequently used to treat metastatic prostate cancer and is increasingly used to treat local and regional prostate cancer. Androgen deprivation has been shown to increase central obesity and insulin resistance, and it can alter serum lipid profiles. Recent data suggest that androgen-deprivation therapy is also associated with incident diabetes and cardiovascular disease and cardiac-related mortality. Patients and physicians making decisions regarding the use of androgen-deprivation therapy should weigh the benefits and possible risks, particularly when androgen-deprivation therapy is being used for indications where benefits have not been clearly defined. They may also want to consider monitoring for possible side effects related to cardiovascular and metabolic outcomes.

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.

Androgen-suppression therapy for prostate cancer and the risk of death in men with a history of myocardial infarction or stroke

OBJECTIVE

To examine the effect of short-course androgen-suppression therapy (AST) before brachytherapy on all-cause mortality (ACM) rates, stratified by the presence or absence of a history of myocardial infarction (MI) or stroke. AST is used to reduce prostate size to enable men with favourable-risk prostate cancer to undergo brachytherapy, but no disease-specific benefit has been reported for this practice, and AST use has been associated with an increased risk of ACM in some men with pre-existing cardiovascular disease.

PATIENTS AND METHODS

The study comprised 12792 men with favourable-risk disease, i.e. a prostate-specific antigen (PSA) level of <20 ng/mL, Gleason score ≤7 and clinical category ≤T2c, treated between 1991 and 2007 at community-based medical centres with brachytherapy ± neoadjuvant AST. Multivariable Cox regression analysis was used to assess whether there were significant associations between AST use in men with a history of MI or stroke and the risk of ACM, adjusting for age, treatment year, and known prognostic factors of prostate cancer.

RESULTS

After a median (interquartile range) follow-up of 3.8 (2.0-5.9) years there were 1557 deaths. The risk of ACM was lower in men with no history of MI or stroke than in those with this history, whether AST was used (adjusted hazard ratio 0.79, 95% confidence interval 0.67-0.92; P= 0.003) or not (0.74, 0.65-0.85; P < 0.001). However, men with a history of MI or stroke treated with AST had a greater risk of ACM than those not treated with AST (1.2, 1.05-1.38; P= 0.008).

CONCLUSION

The use of short-course AST in men with a history of MI or stroke is associated with a greater risk of ACM in men with favourable-risk prostate cancer.

Immediate risk of suicide and cardiovascular death after a prostate cancer diagnosis: cohort study in the United States

BACKGROUND

Receiving a cancer diagnosis is a stressful event that may increase risks of suicide and cardiovascular death, especially soon after diagnosis.

METHODS

We conducted a cohort study of 342,497 patients diagnosed with prostate cancer from January 1, 1979, through December 31, 2004, in the Surveillance, Epidemiology, and End Results Program. Follow-up started from the date of prostate cancer diagnosis to the end of first 12 calendar months after diagnosis. The relative risks of suicide and cardiovascular death were calculated as standardized mortality ratios (SMRs) comparing corresponding incidences among prostate cancer patients with those of the general US male population, with adjustment for age, calendar period, and state of residence. We compared risks in the first year and months after a prostate cancer diagnosis. The analyses were further stratified by calendar period at diagnosis, tumor characteristics, and other variables.

RESULTS

During follow-up, 148 men died of suicide (mortality rate = 0.5 per 1000 person-years) and 6845 died of cardiovascular diseases (mortality rate = 21.8 per 1000 person-years). Patients with prostate cancer were at increased risk of suicide during the first year (SMR = 1.4, 95% confidence interval [CI] = 1.2 to 1.6), especially during the first 3 months (SMR = 1.9, 95% CI = 1.4 to 2.6), after diagnosis. The elevated risk was apparent in pre-prostate-specific antigen (PSA) (1979-1986) and peri-PSA (1987-1992) eras but not since PSA testing has been widespread (1993-2004). The risk of cardiovascular death was slightly elevated during the first year (SMR = 1.09, 95% CI = 1.06 to 1.12), with the highest risk in the first month (SMR = 2.05, 95% CI = 1.89 to 2.22), after diagnosis. The first-month risk was statistically significantly elevated during the entire study period, and the risk was higher for patients with metastatic tumors (SMR = 3.22, 95% CI = 2.68 to 3.84) than for those with local or regional tumors (SMR = 1.57, 95% CI = 1.42 to 1.74).

CONCLUSION

A diagnosis of prostate cancer may increase the immediate risks of suicide and cardiovascular death.

Innovations in the systemic therapy of prostate cancer

Systemic therapy has become an increasingly important component of treatment of advanced prostate cancer. In the past decade, important innovations have been achieved in the development of novel systemic hormonal therapies for the salvage treatment of metastatic castrate-resistant disease. These improvements have been accompanied by the broadening of potential indications for chemotherapy in castrate-resistant metastatic disease and the use of chemotherapy as an adjunct to the treatment of locally extensive tumors. These changes have begun to lead to improved outcomes, but at the expense of novel patterns of late toxic effects. We review the key steps in the recent evolution of systemic therapy of prostate cancer.

Diabetes and cardiovascular disease during androgen deprivation therapy: observational study of veterans with prostate cancer

BACKGROUND

Previous studies indicate that androgen deprivation therapy for prostate cancer is associated with diabetes and cardiovascular disease among older men. We evaluated the relationship between androgen deprivation therapy and incident diabetes and cardiovascular disease in men of all ages with prostate cancer.

METHODS

We conducted an observational study of 37,443 population-based men who were diagnosed with local or regional prostate cancer in the Veterans Healthcare Administration from January 1, 2001, through December 31, 2004, with follow-up through December 31, 2005. Cox proportional hazards models were used to assess whether androgen deprivation therapy with gonadotropin-releasing hormone (GnRH) agonists, oral antiandrogens, the combination of the two (ie, combined androgen blockade), or orchiectomy was associated with diabetes, coronary heart disease, myocardial infarction, sudden cardiac death, or stroke, after adjustment for patient and tumor characteristics. All statistical tests were two-sided.

RESULTS

Overall, 14,597 (39%) of the 37,443 patients were treated with androgen deprivation therapy. Treatment with GnRH agonists was associated with statistically significantly increased risks of incident diabetes (for GnRH agonist therapy, 159.4 events per 1000 person-years vs 87.5 events for no androgen deprivation therapy, difference = 71.9, 95% confidence interval [CI] = 71.6 to 72.2; adjusted hazard ratio [aHR] = 1.28, 95% CI = 1.19 to 1.38), incident coronary heart disease (aHR = 1.19, 95% CI = 1.10 to 1.28), myocardial infarction (12.8 events per 1000 person-years for GnRH agonist therapy vs 7.3 for no androgen deprivation therapy, difference = 5.5, 95% CI = 5.4 to 5.6; aHR = 1.28, 95% CI = 1.08 to 1.52), sudden cardiac death (aHR = 1.35, 95% CI = 1.18 to 1.54), and stroke (aHR = 1.22, 95% CI = 1.10 to 1.36). Combined androgen blockade was statistically significantly associated with an increased risk of incident coronary heart disease (aHR = 1.27, 95% CI = 1.05 to 1.53), and orchiectomy was associated with coronary heart disease (aHR = 1.40, 95% CI = 1.04 to 1.87) and myocardial infarction (aHR = 2.11, 95% CI = 1.27 to 3.50). Oral antiandrogen monotherapy was not associated with any outcome studied.

CONCLUSION

Androgen deprivation therapy with GnRH agonists was associated with an increased risk of diabetes and cardiovascular disease.

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.

Androgen deficiency and atherosclerosis: The lipid link

The relationship between androgen deficiency and atherosclerosis is complex, poorly understood, and remains controversial. The aim of this review is to evaluate the data in the literature to determine if androgen deficiency modulates lipid profiles and contributes to atherosclerosis development or progression. Studies in animals and humans suggest that androgen deficiency is associated with increased triglycerides (TGs), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C). Although the effects of androgen deficiency on high-density lipoprotein cholesterol (HDL-C) remains controversial, recent data suggest that androgen therapy is associated with increased levels of HDL-C and may improve reverse cholesterol transport. Animal studies suggested that androgen deprivation adversely affect lipid profiles and this was reversed by androgen treatment. Furthermore, androgen treatment of hypogonadal men significantly improved lipid profiles. Emerging data indicate that androgens play an important role in lipid metabolism. Therefore androgens are critical in the prevention and progression of atherosclerosis. Androgen deficiency contributes to increased TGs, TC, LDL-C and reduced HDL-C while androgen treatment results in a favorable lipid profile, suggesting that androgens may provide a protective effect against the development and/or progression of atherosclerosis.

Androgen deprivation therapy and estrogen deficiency induced adverse effects in the treatment of prostate cancer

Androgen deprivation therapy (ADT) is the standard of care for metastatic prostate cancer and is increasingly used to treat asymptomatic patients with prostate-specific antigen recurrence after failed primary therapy. Although effective, ADT is associated with multiple adverse effects, many of which are related to the estrogen deficiency that occurs as a result of treatment. These include increased fracture risk, hot flashes, gynecomastia, serum lipid changes and memory loss. By providing clinicians with a greater awareness of the estrogen deficiency induced adverse effects from ADT, they can proactively intervene on the physical and psychological impact these effects have on patients.

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.

Cardiovascular and metabolic complications during androgen deprivation: exercise as a potential countermeasure

Apart from the well-established adverse musculoskeletal and sexual health effects of androgen deprivation therapy (ADT), evidence is accumulating of substantial ADT-related cardiovascular and metabolic complications, which may impact quality of life and overall survival. In this brief review we discuss (1) the incidence of cardiovascular and metabolic complications during/following ADT from large cohort studies, (2) the increased risk factors for cardiovascular and metabolic disease from cross-sectional and prospective studies and (3) the use of physical exercise as a countermeasure in this new era of ADT-related toxicity. It is clear that exercise has the potential to provide a myriad of benefits to men undergoing ADT that may result in reduced morbidity and mortality, and subsequently improve quality of life.

Metabolic complications of androgen deprivation therapy for prostate cancer

PURPOSE

Androgen deprivation therapy has a variety of well recognized adverse effects including vasomotor flushing, loss of libido, fatigue, gynecomastia, anemia and osteoporosis. This review focuses on the more recently described metabolic complications of androgen deprivation therapy including obesity, insulin resistance and lipid alterations as well as the association of androgen deprivation therapy with diabetes and cardiovascular disease.

MATERIALS AND METHODS

We reviewed the medical literature using the PubMed(R) search terms prostate cancer, androgen deprivation therapy, gonadotropin-releasing hormone agonists, obesity, insulin resistance, lipids, diabetes, cardiovascular disease and myocardial infarction. We provide a focused review and our perspective on the relevant literature.

RESULTS

Androgen deprivation therapy decreases lean mass and increases fat mass. It also decreases insulin sensitivity while increasing low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglycerides. Consistent with these adverse metabolic effects, androgen deprivation therapy may be associated with a greater incidence of diabetes and cardiovascular disease. Some of these androgen deprivation therapy related metabolic changes (obesity, insulin resistance and increased triglycerides) overlap with features of the metabolic syndrome. However, in contrast to the metabolic syndrome, androgen deprivation therapy increases subcutaneous fat and high density lipoprotein cholesterol.

CONCLUSIONS

Androgen deprivation therapy increases obesity, decreases insulin sensitivity and adversely alters lipid profiles. It may be associated with a greater incidence of diabetes and cardiovascular disease. The benefits of androgen deprivation therapy should be weighed against these and other potential harms. Little is known about the optimal strategy to mitigate the adverse metabolic effects of androgen deprivation therapy. Thus, we recommend an emphasis on existing strategies for screening and treatment that have been documented to reduce the risk of diabetes and cardiovascular disease in the general population.

Binding site of activators of the cystic fibrosis transmembrane conductance regulator in the nucleotide binding domains

The use of substances that could activate the defective chloride channels of the mutant cystic fibrosis transmembrane conductance regulator (CFTR) has been suggested as possible therapy for cystic fibrosis. Using epithelia formed by cells stably transfected with wildtype or mutant (G551D, G1349D) CFTR, we estimated the apparent dissociation constant, K(D), of a series of CFTR activators by measuring the increase in the apical membrane current. Modification of apparent K(D) of CFTR activators by mutations of the nucleotide-binding domains (NBDs) suggests that the binding site might be in these regions. The human NBD structure was predicted by homology with murine NBD1. An NBD1-NBD2 complex was constructed by overlying monomers to a bacterial ABC transporter NBD dimer in the "head-to-tail" conformation. Binding sites for CFTR activators were predicted by molecular docking. Comparison of theoretical binding free energy estimated in the model to free energy estimated from the apparent dissociation constants, K(D), resulted in a remarkably good correlation coefficient for one of the putative binding sites, located in the interface between NBD1 and NBD2.