Prostate-specific antigen testing for prostate cancer: the case for informed consent

Can exercise ameliorate treatment toxicity during the initial phase of testosterone deprivation in prostate cancer patients? Is this more effective than delayed rehabilitation?

BACKGROUND

There has been substantial increase in use of androgen deprivation therapy as adjuvant management of prostate cancer. However, this leads to a range of musculoskeletal toxicities including reduced bone mass and increased skeletal fractures compounded with rapid metabolic alterations, including increased body fat, reduced lean mass, insulin resistance and negative lipoprotein profile, increased incidence of cardiovascular and metabolic morbidity, greater distress and reduced quality of life. Numerous research studies have demonstrated certain exercise prescriptions to be effective at preventing or even reversing these treatment toxicities. However, all interventions to date have been of rehabilitative intent being implemented after a minimum of 3 months since initiation of androgen deprivation, by which time considerable physical and psychological health problems have manifested. The pressing question is whether it is more efficacious to commence exercise therapy at the same time as initiating androgen deprivation, so treatment induced adverse effects can be immediately attenuated or indeed prevented.

METHODS/DESIGN

We are proposing a multi-site randomized controlled trial with partial crossover to examine the effects of timing of exercise implementation (immediate or delayed) on preserving long-term skeletal health, reversing short- and long-term metabolic and cardiovascular risk factors, and supporting mental health in men receiving androgen deprivation therapy. 124 men who are about to initiate androgen deprivation for prostate cancer will be randomized to immediate or delayed groups. Immediate will commence a 6-month exercise program within 7-10 days of their first dose. Delayed will receive usual care for 6 months and then commence the exercise program for 6 months (partial cross-over). Immediate will be free to adopt the lifestyle of their choosing following the initial 6-month intervention. Measurements for primary and secondary endpoints will take place at baseline, 6 months and 12 months.

DISCUSSION

This project is unique as it explores a fundamental question of when exercise implementation will be of most benefit and addresses both physical and psychological consequences of androgen deprivation initiation. The final outcome may be adjunct treatment which will reduce if not prevent the toxicities of androgen deprivation, ultimately resulting in reduced morbidity and mortality for men with prostate cancer.

TRIAL REGISTRATION

ACTRN12612000097842.

Physical activity and genitourinary cancer survivorship

In this chapter we discuss common toxicities arising from genitourinary cancer treatments, in particular the adverse effects from androgen deprivation therapy (ADT) for prostate cancer given its well established detrimental effects on physical, physiological, and psychological function, and existing physical activity research in the postdiagnosis period including studies focusing on supportive care and some limited data on disease outcomes. Overall, consistent positive outcomes have been reported across studies showing that exercise is beneficial to reduce a number of treatment-related toxicities and improve symptoms. Additional studies are needed in genitourinary cancers other than prostate to establish specific physical activity requirements and implementation strategies.

A phase III clinical trial of exercise modalities on treatment side-effects in men receiving therapy for prostate cancer

Background

Androgen deprivation therapy (ADT) is accompanied by a number of adverse side effects including reduced bone mass and increased risk for fracture, reduced lean mass and muscle strength, mood disturbance and increased fat mass compromising physical functioning, independence, and quality of life. The purpose of this investigation is to examine the effects of long term exercise on reversing musculoskeletal-related side effects, and cardiovascular and diabetes risk factors in men receiving androgen deprivation for their prostate cancer. Specifically, we aim to investigate the effects of a 12-month exercise program designed to load the musculoskeletal system and reduce cardiovascular and diabetes disease progression on the following primary endpoints: 1) bone mineral density; 2) cardiorespiratory function and maximal oxygen capacity; 3) body composition (lean mass and fat mass); 4) blood pressure and cardiovascular function; 5) lipids and glycemic control; and 6) quality of life and psychological distress.

Methods/Design

Multi-site randomized controlled trial of 195 men (65 subjects per arm) undergoing treatment for prostate cancer involving ADT in the cities of Perth and Brisbane in Australia. Participants will be randomized to (1) resistance/impact loading exercise, (2) resistance/cardiovascular exercise groups and (3) usual care/delayed exercise. Participants will then undergo progressive training for 12 months. Measurements for primary and secondary endpoints will take place at baseline, 6 and 12 months (end of the intervention).

Discussion

The principal outcome of this project will be the determination of the strength of effect of exercise on the well established musculoskeletal, cardiovascular and insulin metabolism side effects of androgen deprivation in prostate cancer patients. As this project is much longer term than previous investigations in the area of exercise and cancer, we will gain knowledge as to the continuing effects of exercise in this patient population specifically targeting bone density, cardiovascular function, lean and fat mass, physical function and falls risk as primary study endpoints. In terms of advancement of prostate cancer care, we expect dissemination of the knowledge gained from this project to reduce fracture risk, improve physical and functional ability, quality of life and ultimately survival rate in this population.

Clinical Trial Registry

A Phase III clinical trial of exercise modalities on treatment side-effects in men receiving therapy for prostate cancer; ACTRN12609000200280

Long-term effects of intermittent androgen suppression on testosterone recovery and bone mineral density: results of a 33-month observational study

OBJECTIVE

To investigate changes in bone mineral density (BMD) and osteoporosis, over 3 years of intermittent androgen-suppression therapy (IAST).

PATIENTS AND METHODS

This was a Phase II individual cohort study of 72 patients with prostate cancer without metastatic bone disease, enrolled between 1999 and 2002. Patients had 9 months flutamide (250 mg, three times daily) and leuprolide (22.5 mg, 3-monthly depot) after which, patients ceased therapy providing that their PSA levels were <4 ng/mL. AST re-commenced when the PSA level exceeded the pretreatment level or was >20 ng/mL. BMD for hip and spine was the primary endpoint; assessed at baseline; completion of initial treatment period; and at 1 and 2 years after initial treatment (POST period).

RESULTS

Osteoporosis increased from 7% at baseline to 10% at 3 years. The BMD declined after 9 months treatment, at -1.9% and -3.3% at hip and spine, respectively (P < 0.001). Subsequent BMD decline in the POST period was attenuated; at 1 years and 2 years later, hip -0.6% (not significant), and -0.8% (P < 0.014), and spine +1.0% and +0.2% (not significant). The BMD change in those remaining 'off' therapy for 2 years (n = 20) was strongly associated with the level of testosterone recovery; a peak testosterone level of <5 nmol/L associated with a greater then normal physiological loss. Testosterone recovery was less likely in older men.

CONCLUSION

The attenuation of spine and hip BMD decline after 3-year IAST compared with those reported for continuous AST appears to be due to testosterone driven BMD recovery in the POST period. Failure of testosterone recovery was associated with worse final BMD. By reducing the potential risk for adverse bone complications, intermittent therapy may become an important consideration when the therapeutic ratio is narrow.

Exercise can prevent and even reverse adverse effects of androgen suppression treatment in men with prostate cancer

Side effects accompanying androgen deprivation therapy (ADT), including sarcopenia, loss of bone mass and reduction in muscle strength, can compromise physical function, particularly in older patients. Exercise, specifically resistance training, may be an effective and cost-efficient strategy to limit or even reverse some of these adverse effects during and following therapy. In this review, we discuss common morphological and physiological ADT-related side effects or 'Androgen Deprivation and Sarcopenia-Related Disorders' and the existing clinical trials incorporating physical exercise in prostate cancer patients receiving active therapy. Further, training concepts and guidelines are provided for prescribing resistance exercise programs for this population.

Adverse effects to quality of life arising from treatment can recover with intermittent androgen suppression in men with prostate cancer

Health-related quality of life (HQOL) research is a means of broadening the assessment of treatment effects. This longitudinal study investigated the dynamic change to quality of life (QOL) and testosterone dependant physiology in men commencing an intermittent maximal androgen blockade program (IMAB). Two hundred and fifty men were accrued to the multi-centre study of IMAB (Flutamide 250 mg TDS, Leuprolide 22.5 mg depot) ceasing treatment after 9 months if PSA <4 ng/ml, and restarting when PSA >20 ng/ml. QOL was assessed every 3 months for 30 months using the EORTC QLQ-C30 and EORTC QLQ-PR25 module. Data completion for the whole study was 90%. At baseline, our cohort was less symptomatic and had better function than the EORTC reference cohort, which may be related to a shift in clinical practice with time. Testosterone suppression (AS) lead to a significant reduction in global HQOL and deterioration in most function and symptom scales. During the off period, there was a trend of progressive improvement in HQOL that paralleled testosterone recovery but was slower than the rate of deterioration during the treatment phase. Maximum recovery of HQOL occurred most frequently by months 9-12. Testosterone recovery was slower and less complete in older men, and lead to concomitant poorer HOQL recovery. Whilst the magnitude of mean change to scale scores was small, there was a consistent and simultaneous deterioration during maximal androgen blockade (MAB) and improvement during androgen recovery. Older men are more likely to show an impaired testosterone recovery, and this was paralleled by a slower HQOL recovery. Newer methods of analysis to describe results in a way that has meaning to the individual patient are warranted.

Rising incidence of prostate cancer in Scotland: increased risk or increased detection?

OBJECTIVE

To assess the extent to which the increasing incidence of prostate cancer in Scotland can be explained by increased detection, particularly through transurethral resection of the prostate (TURP) and use of the prostate-specific antigen (PSA) test. Subjects and methods This population-based study was confined to men resident in Scotland and aged > or =50 years. Temporal trends were examined in age-specific and age-standardized incidence, mortality and TURP rates, and PSA testing rates during 1981-1996. Also analysed were the geographical variations in age-standardized incidence and mortality rates during two distinct periods, 1984-1986 (before PSA testing) and 1994-1996 (after PSA testing). Finally, incidence rates and relative survival at 5 years were calculated by age group and 5-year periods of diagnosis during 1968-1992.

RESULTS

The incidence of prostate cancer in men aged > or = 50 years increased from an age-standardized rate of 142.0 per 100 000 in 1981 to 240.9 in 1996, with the steepest increase occurring between 1992 and 1993. The mortality rate increased similarly until 1993, but was relatively stable thereafter, falling slightly in 1996. In 1981-1988, incidence rates were closely correlated with TURP rates (r = 0.98, P<0.001). In 1989-1996, incidence was closely correlated with PSA testing rates (r = 0.98, P<0.001). By 1994-1996, incidence rates varied substantially between Scottish mainland health boards (range 167.7-303.0 per 100 000), with much less variation in mortality rates (90.7-110.0). Relative survival has increased recently in all age groups although, in the era before PSA testing, survival was reasonably stable despite increasing incidence.

CONCLUSION

Although there may have been a true increase in risk, much of the observed increase in the incidence of prostate cancer in Scotland between 1981 and 1996 has been caused by increased detection, leading recently to considerable variation among different areas of the country. The extent to which this represents the early diagnosis of tumours which would eventually cause symptoms or be life-threatening, or detection of latent disease which would never have become symptomatic, is not clear. There is no evidence so far that the increased incidence is associated with any substantial reduction in mortality.

Prostate cancer testing: behaviour, motivation and attitudes among Western Australian men

OBJECTIVE

To estimate the proportion of Western Australian men aged 40-80 years who had been tested for prostate cancer, their experiences of screening and perception of its benefit.

DESIGN AND SETTING

Cross-sectional survey (random telephone survey) of Western Australian men conducted in February 1998.

PARTICIPANTS

400 men aged 40-80 years from 670 eligible households (60% response rate from contactable households with eligible men).

MAIN OUTCOME MEASURES

Proportion of respondents tested for prostate cancer (by prostate-specific antigen [PSA] test or digital rectal examination); reasons for having been tested; information provided by the doctor before testing; reasons given for and beliefs about the benefits of testing.

RESULTS

Of 391 asymptomatic men, 220 (56%) recalled having been tested for prostate cancer and 167 (43%) had had a PSA test. Of those tested, 86% had their first test in the previous five years. The two most common reasons for testing were media publicity and general practitioner recommendation. Thirty-eight per cent of men tested during the previous five years reported that the doctor did not discuss the "pros and cons" of the test; 39% reported a discussion of less than five minutes' duration; 17% were given printed information before undergoing the test for the first time. Half were "very convinced" of the benefits of testing for prostate cancer.

CONCLUSIONS

Men are being tested for prostate cancer with minimal pretest counselling or written information.