Parenteral polyoestradiol phosphate vs orchidectomy in the treatment of advanced prostatic cancer. Efficacy and cardiovascular complications: a 2-year follow-up report of a national, prospective prostatic cancer study. Finnprostate Group

Trials of testosterone replacement reporting cardiovascular adverse events

The numbers of testosterone prescriptions written have increased several-fold worldwide, but the incidence of pathological hypogonadism due to hypothalamic, pituitary, and testicular disease has remained unchanged. Most of these prescriptions are being dispensed to middle-aged and older men who have experienced age-related decline in serum testosterone levels; a subset of the population in which benefits of testosterone replacement is at best, modest. Recently, some randomized controlled trials have reported increased cardiovascular events in men (mainly older men and those with prevalent cardiovascular disease) with testosterone use, and a few recent meta-analyses have confirmed these findings. In this review, we discuss trials of testosterone therapy that have reported higher cardiovascular events, relevant trials that have not reported increased cardiovascular events and large trials that have focused on cardiovascular risk (mainly atherosclerosis progression) as their main outcome. We also review findings from meta-analyses that have evaluated cardiovascular events in various testosterone trials. Finally, we discuss some potential mechanisms by which testosterone use might result in an increased cardiovascular risk. As none of the trials conducted to date were adequately powered to evaluate cardiovascular events, no firm conclusions can be drawn regarding the cardiovascular safety of testosterone therapy at this time. In the interim, we hope that this review will help practitioners make informed decisions regarding the care of their patients.

Mortality, cardiovascular risk, and androgen deprivation therapy for prostate cancer: A systematic review with direct and network meta-analyses of randomized controlled trials and observational studies

Androgen deprivation therapy (ADT) is a cornerstone therapy for advanced prostate cancer (PCa). We hypothesized that cardiovascular (CV) risk is different across the various ADT modalities to compare their effects on CV morbidity and mortality, and all-cause mortality in patients with PCa. To investigate more in depth potential CV risk heterogeneity focusing on coronary (main outcome) and cerebrovascular risk, CV, and overall mortality. We performed a Medline and Embase query, without language restriction, since 1950 up to July 2014. We included randomized controlled trials (RCTs) and observational studies providing that they compared at least 1 ADT modality to another one or to placebo and they gave data on CV event or all-cause mortality. Sixty-eight studies out of 3419 met our eligibility criteria. Eleven observational studies were analyzed. Direct meta-analyses showed that antiandrogen was associated with a 30% decrease risk for myocardial infarction (MI) compared to GnRH agonists (RR, 0.70 [0.54-0.91]); combined androgen blockade (CAB) was associated with a 10% increase risk for stroke when compared to antiandrogen (RR, 1.10 [1.02-1.19]). With regard to RCTs, 57 were included: direct meta-analyses suggested that CAB was associated with a 10% decrease of all-cause mortality when compared to GnRH agonist (RR, 0.90 [0.82-1.00]). Network analysis could only be performed for all-cause mortality and it remains difficult to disentangle benefit (positive impact on cancer survival) and risk (including CV risk). The impact of the ADT modalities on CV morbidity remains difficult to quantify and more detailed prospective collection is required.

REGISTRATION

PROSPERO, CRD42014010598.

Cardiovascular effects of hormone therapy for prostate cancer

Androgen deprivation therapy (ADT) has been the mainstay of treatment for advanced prostate cancer for decades, and has been shown to control disease and improve symptoms. In addition, for men with high-risk localized or locally advanced prostate cancer, short-course ADT in combination with radiotherapy improves survival. There is evidence that ADT increases cardiovascular risk, particularly in men with preexisting cardiovascular disease. This increased risk may apply even with short-course ADT. In an individual patient, the benefits of ADT should be balanced against the risk, and patients who require ADT should have risk factors for cardiovascular disease optimized. There is some evidence to suggest that more contemporary methods of delivering ADT may reduce cardiovascular risk.

Risk and timing of cardiovascular disease after androgen-deprivation therapy in men with prostate cancer

PURPOSE

Findings on the association between risk of cardiovascular disease (CVD) and the duration and type of androgen-deprivation therapy (ADT) in men with prostate cancer (PCa) are inconsistent.

METHODS

By using data on filled drug prescriptions in Swedish national health care registers, we investigated the risk of CVD in a cohort of 41,362 men with PCa on ADT compared with an age-matched, PCa-free comparison cohort (n = 187,785) by use of multivariable Cox proportional hazards regression models.

RESULTS

From 2006 to 2012, 10,656 men were on antiandrogens (AA), 26,959 were on gonadotropin-releasing hormone (GnRH) agonists, and 3,747 underwent surgical orchiectomy. CVD risk was increased in men on GnRH agonists compared with the comparison cohort (hazard ratio [HR] of incident CVD, 1.21; 95% CI, 1.18 to 1.25; and orchiectomy: HR, 1.16; 95% CI, 1.08 to 1.25). Men with PCa on AA were at decreased risk (HR of incident CVD, 0.87; 95% CI, 0.82 to 0.91). CVD risk was highest during the first 6 months of ADT in men who experienced two or more cardiovascular events before therapy, with an HR of CVD during the first 6 months of GnRH agonist therapy of 1.91 (95% CI, 1.66 to 2.20), an HR of CVD with AA of 1.60 (95% CI, 1.24 to 2.06), and an HR of CVD with orchiectomy of 1.79 (95% CI, 1.16 to 2.76) versus the comparison cohort.

CONCLUSION

Our results support that there should be a solid indication for ADT in men with PCa so that benefit outweighs potential harm; this is of particular importance among men with a recent history of CVD.

The course of metastatic prostate cancer under treatment

The first-line management of metastatic prostate cancer is hormonal therapy. However, resistance to this treatment will emerge within an average of 24 months. Our purpose was to determine the course of metastatic prostate cancer under treatment.

A total of 56 patients who were diagnosed with metastatic prostate cancer were enrolled. As initial management, 3 kinds of hormonal therapy consisting of bilateral orchiectomy (BSO) alone, BSO + anti-androgene (AA) and LH-RH + AA were applied. The patients were followed until the emergence of hormone resistance. Serum PSA levels at the time of first diagnosis, post-treatment nadir PSA levels, time to nadir PSA, time to hormonal resistance and PSA levels at hormonal resistance were assessed, retrospectively. The localization and number of metastases and the survival term from the beginning of the emergence of hormone resistance until death were investigated

No significant differences could be established between the groups. The mean time to reach hormone refractory status was 30.3 months for the whole study group. The average term of survival was 42.7 months for the whole group. Distance metastases were found in 8 patients during follow-up.

There were no statistical differences between the groups in terms of treatment modalities applied for metastatic prostate cancer. Patients with androgen independent prostate cancer demonstrated progression despite chemical or surgical castration, and had poor prognosis. Initial hormonal therapy failed after an average of 2 years in metastatic prostate cancer.

Endocrine prevention and treatment of prostate cancer

The major androgen within the prostate is dihydrotestosterone (DHT). DHT and 5α-reductase are highly associated with prostate cancer. It has been hypothesised that inhibition of 5α-reductase activity might reduce the risk of prostate cancer development, slow tumour progression and even treat the existing disease. The basis for endocrine treatment of prostate cancer is to deprive the cancer cells of androgens. Every type of endocrine treatment carries adverse events which influence quality of life in different ways. 5α-Reductase inhibitors (5-ARI) reduce risk of being diagnosed with prostate cancer but they do not eliminate it. By suppressing PSA from BPH and indolent prostate cancers 5-ARI enhances the ability of a rising PSA to define a group of men at increased risk of clinically significant prostate cancer. Also fewer high-grade cancers are missed because biopsy is more accurate in smaller prostates. Androgen deprivation is an effective treatment for patients with advanced prostate cancer. However, it is not curative, and creates a spectrum of unwanted effects that influence quality of life. Castration remains the frontline treatment for metastatic prostate cancer, where orchiectomy, oestrogen agonists, GnRH agonists and antagonists produce equivalent clinical responses. MAB is not significantly more effective than single agent GnRH agonist or orchiectomy. Nonsteroidal antiandrogen monotherapy is as effective as castration in treatment of locally advanced prostate cancer offering quality of life benefits. Neoadjuvant endocrine treatment has its place mainly in the external beam radiotherapy setting. Increasing data suggest IAD is as effective as continuous ADT. The decision regarding the type of androgen deprivation should be made individually after informing the patient of all available treatment options, including watchful waiting, and on the basis of potential benefits and adverse effects. There are new promising secondary or tertiary forms of endocrine therapies under evaluation, like CTP17A1 inhibitors and more potent antiandrogens including MDV3100, which give new hope for patients developing castration resistant prostate cancer.

Risk factors associated with cardiovascular events during testosterone administration in older men with mobility limitation

BACKGROUND

Testosterone in Older Men with Mobility Limitations Trial found an increased incidence of cardiovascular events in men randomized to testosterone, resulting in enrollment cessation by trial's Data and Safety Monitoring Board. We evaluated changes in gonadal hormones and markers of inflammation and coagulation to elucidate risk factors associated with cardiovascular events.

METHODS

Men aged 65 years or more, with mobility limitation, total testosterone 100-350 ng/dL, or free testosterone less than 50 pg/mL, were randomized to placebo or 10 g testosterone gel daily for 6 months. Changes in total and free testosterone, estradiol and estrone, C-reactive protein, interleukin 6, fibrinogen, plasminogen activator inhibitor-1, and pro-brain naturetic peptide were compared between groups and within the testosterone group between subjects who experienced cardiovascular events and those who did not.

RESULTS

Of 209 men randomized (mean age 74 years), gonadal hormones and biomarkers were available in 179 men. Baseline body mass index, gonadal hormones, lipids, Framingham risk scores, and other biomarkers were similar in the two treatment groups. Within the testosterone group, the 6-month increase in free testosterone was significantly greater in men who experienced cardiovascular events than in those who did not [mean (95% confidence interval), 10.6 (4.6-16.7) vs 5.2 (3.0-7.5) ng/dL, p = .05]. In multivariable logistic regression analysis, the change in the serum levels of free testosterone was associated with cardiovascular events.

CONCLUSION

Mobility-limited older men who experienced cardiovascular events had greater increases in serum free testosterone levels than those who did not.

Prognostic grouping of metastatic prostate cancer using conventional pretreatment prognostic factors

OBJECTIVE

To develop three prognostic groups for disease specific mortality based on the binary classified pretreatment variables age, haemoglobin concentration (Hb), erythrocyte sedimentation rate (ESR), alkaline phosphatase (ALP), prostate-specific antigen (PSA), plasma testosterone and estradiol level in hormonally treated patients with metastatic prostate cancer (PCa).

MATERIAL AND METHODS

The present study comprised 200 Finnprostate 6 study patients, but data on all variables were not known for every patient. The patients were divided into three prognostic risk groups (Rgs) using the prognostically best set of pretreatment variables. The best set was found by backward stepwise selection and the effect of every excluded variable on the binary classification cut-off points of the remaining variables was checked and corrected when needed.

RESULTS

The best group of variables was ALP, PSA, ESR and age. All data were known in 142 patients. Patients were given one risk point each for ALP > 180 U/l (normal value 60-275 U/l), PSA > 35 microg/l, ESR > 80 mm/h and age < 60 years. Three risk groups were formed: Rg-a (0-1 risk points), Rg-b (2 risk points) and Rg-c (3-4 risk points). The risk of death from PCa increased statistically significantly with advancing prognostic group.

CONCLUSION

Patients with metastatic PCa can be divided into three statistically significantly different prognostic risk groups for PCa-specific mortality by using the binary classified pretreatment variables ALP, PSA, ESR and age.

Cardiovascular complications in patients with advanced prostatic cancer treated by means of orchiectomy or polyestradiol phosphate

OBJECTIVE

To evaluate the cardiovascular (CV) complications associated with orchiectomy (OE) and parenteral polyestradiol phosphate (PEP) therapy (240 mg/month), taking into account the effect of pretreatment diseases and pretreatment medication.

MATERIAL AND METHODS

A total of 244 T3-4 M0 patients and 200 T1-4 M1 patients were randomized to either OE or PEP therapy. The two groups of patients were analyzed separately. The follow-up period was 36 months. The effect of pretreatment vascular and other diseases and pretreatment medication which may be associated with a risk of CV complications was evaluated.

RESULTS

In the T3-4 M0 patients, the treatment (PEP versus OE) and the presence of pretreatment vascular diseases were statistically significantly associated with a risk of CV complications (p=0.01 and 0.003, respectively). In the T1-4 M1 patients, such an association was not found. No association was observed between pretreatment medication and CV complications. There was no difference in progression-free time between the therapy groups in either the T3-4 M0 or T1-4 M1 patients.

CONCLUSION

In patients with locally advanced prostatic cancer, PEP therapy is associated with a statistically significantly higher risk of CV complications compared to OE.

Parenteral oestrogen in the treatment of prostate cancer: a systematic review

The objectives of this study were to assess the effectiveness and safety of parenteral oestrogen in the treatment of prostate cancer, and to examine any dose relationship. A systematic review was undertaken. Electronic databases, published paper and internet resources were searched to locate published and unpublished studies with no restriction by language or publication date. Studies included were randomised controlled trials of parenteral oestrogen in patients with prostate cancer; other study designs were also included to examine dose-response. Study selection, appraisal, data extraction and quality assessment were performed by one reviewer and independently checked by another. Twenty trials were included in the review. The trials differed with regard to the included patients, formulation and dose of parenteral oestrogen, comparator used, outcome measures reported and the duration of follow-up. The results provide no evidence to suggest that parenteral oestrogen, in doses sufficient to produce castrate levels of testosterone, is less effective than luteinising hormone-releasing hormone (LHRH) or orchidectomy in controlling prostate cancer, or that it is consistently associated with an increase in cardiovascular mortality. Further well-conducted trials of parenteral oestrogen are required. A pilot randomised controlled trial comparing transdermal oestrogen to LHRH analogues in men with locally advanced or metastatic prostate cancer is underway in the United Kingdom.

Low Serum Testosterone and High Serum Estradiol Associate With Lower Extremity Peripheral Arterial Disease in Elderly Men

OBJECTIVES

This study sought to determine whether serum levels of testosterone and estradiol associate with lower extremity peripheral arterial disease (PAD) in a large population-based cohort of elderly men.

BACKGROUND

Few studies have explored the relationship between serum sex steroids and lower extremity PAD in men.

METHODS

The Swedish arm of the MrOS (Osteoporotic Fractures in Men) study (n = 3,014; average age 75.4 years) assessed ankle-brachial index (ABI) and defined lower extremity PAD as ABI <0.90. Radioimmunoassay measured serum levels of total testosterone, estradiol, and sex hormone-binding globulin, and we calculated free testosterone and free estradiol levels from the mass action equations.

RESULTS

A linear regression model including age, current smoking, previous smoking, diabetes, hypertension, body mass index, free testosterone, and free estradiol showed that free testosterone independently and positively associates with ABI (p < 0.001), whereas free estradiol independently and negatively associates with ABI (p < 0.001). Logistic regression analyses showed that free testosterone in the lowest quartile (vs. quartiles 2 to 4; odds ratio [OR] 1.65, 95% confidence interval [CI] 1.22 to 2.23, p = 0.001) and free estradiol in the highest quartile (vs. quartiles 1 to 3; OR 1.45, 95% CI 1.09 to 1.94, p = 0.012) independently associate with lower extremity PAD.

CONCLUSIONS

This cross-sectional study shows for the first time that low serum testosterone and high serum estradiol levels associate with lower extremity PAD in elderly men. Future prospective and interventional studies are needed to establish possible causal relationships between sex steroids and the development of lower extremity PAD in men.

Circulating estradiol is an independent predictor of progression of carotid artery intima-media thickness in middle-aged men

CONTEXT

Estrogen treatment of men with prostate cancer is associated with increased cardiovascular morbidity and mortality; however, the role of endogenous estrogen levels for atherosclerotic disease in men is unknown.

OBJECTIVE

The objective of the study was to determine whether endogenous serum estradiol (E2) levels predict the progression of carotid artery intima-media thickness in men.

DESIGN, SETTING AND PARTICIPANTS

This was a population-based, prospective cohort study (the Atherosclerosis and Insulin Resistance study) conducted in Göteborg, Sweden, among 313 Caucasian men without cardiovascular or other clinically overt diseases. Carotid artery intima-media thickness, an index of preclinical atherosclerosis, was measured by ultrasound at baseline (58 yr of age) and after 3 yr of follow-up. Serum sex hormone levels and cardiovascular risk factors (body mass index, waist to hip ratio, systolic blood pressure, serum triglycerides, plasma c-peptide, and smoking status) were assessed at study entry.

INTERVENTION

There was no intervention.

MAIN OUTCOME MEASURES

Association between baseline total and free E2 levels and progression of carotid intima-media thickness over 3 yr with adjustments for cardiovascular risk factors was measured.

RESULTS

In univariate analyses, both total and free E2 levels at baseline were positively associated with the annual change in intima-media thickness. In linear regression models including E2 and cardiovascular risk factors, low-density lipoprotein and high-density lipoprotein cholesterol and E2 were identified as independent predictors of progression of carotid artery intima-media thickness (total E2 beta = 0.187, P = 0.001; and free E2 beta = 0.183, P = 0.003).

CONCLUSIONS

Circulating E2 is a predictor of progression of carotid artery intima-media thickness in middle-aged men. Further studies are needed to investigate the role of endogenous E2 for incident cardiovascular disease events.

Therapy Insight: parenteral estrogen treatment for prostate cancer—a new dawn for an old therapy

Oral estrogens were the treatment of choice for carcinoma of the prostate for over four decades, but were abandoned because of an excess of cardiovascular and thromboembolic toxicity. It is now recognized that most of this toxicity is related to the first pass portal circulation, which upregulates the hepatic metabolism of hormones, lipids and coagulation proteins. Most of this toxicity can be avoided by parenteral (intramuscular or transdermal) estrogen administration, which avoids hepatic enzyme induction. It also seems that a short-term but modest increase in cardiovascular morbidity (but not mortality) is compensated for by a long-term cardioprotective benefit, which accrues progressively as vascular remodeling develops over time. Parenteral estrogen therapy has the advantage of giving protection against the effects of andropause (similar to the female menopause), which are induced by conventional androgen suppression and include osteoporotic fracture, hot flashes, asthenia and cognitive dysfunction. In addition, parenteral estrogen therapy is significantly cheaper than contemporary endocrine therapy, with substantive economic implications for health providers.

Changes in vascular flow after transdermal oestradiol therapy for prostate cancer: a mechanism for cardiovascular toxicity and benefit?

OBJECTIVE

To report the influence of transdermal oestradiol therapy on the vascular dynamics of men with advanced prostate cancer.

PATIENTS AND METHODS

Twenty patients with newly diagnosed locally advanced or metastatic prostate cancer (10 each) were treated using transdermal oestradiol patches. The vascular flow was assessed 6-monthly before and during a year of therapy using arterial and venous Doppler and duplex ultrasonography, arterial and venous photoplethysmography and opto-electronic plethysmography.

RESULTS

Arterial flow, as measured by the mean and peak systolic velocities and photoplethysmography, significantly increased over time. Arterial compliance initially decreased but had normalized after 12 months. The venous variables were unaffected. As a result, the total limb blood flow and the capillary filtration rate were significantly increased.

CONCLUSION

Transdermal oestradiol therapy causes an increase in arterial but not venous flow, and an initial decrease in arterial compliance, which adapts to the physiological range with time. It is possible that these changes may account for the increase in cardiovascular toxicity seen in the early phase of oestrogen therapy, and the cardioprotective effect that accrues thereafter.

Endocrine treatment of prostate cancer

Although androgen deprivation as a treatment for patients with prostate cancer was described more than 60 years ago its optimal use remains controversial. The widespread use of prostate-specific (PSA) assay has lead to earlier diagnosis and earlier detection of recurrent disease. This means that the systemic side effects of androgen deprivation and quality of life have become more important. Debates continue regarding the proper use and timing of endocrine therapy with orchiectomy, oestrogen agonists, gonadotropin hormone-releasing hormone (GnRH) agonists, GnRH antagonists, and androgen antagonists. A critical review of the literature was performed. Data support that androgen deprivation is an effective treatment for patients with advanced prostate cancer. However, although it improves survival, it is not curative, and creates a spectrum of unwanted effects that influence quality of life. Castration remains the frontline treatment for metastatic prostate cancer, where orchiectomy, oestrogen agonists and GnRH agonists produce equivalent clinical responses. Maximum androgen blockade (MAB) is not significantly more effective than single agent GnRH agonist or orchiectomy. Nonsteroidal antiandrogen monotherapy is as effective as castration in treatment of locally advanced prostate cancer offering quality of life benefits. Adjuvant endocrine treatment is able to delay disease progression at any stage. There is, however, controversy of the possible survival benefit of such treatment, including patients having PSA relapse after definitive local treatment for prostate cancer. Neoadjuvant endocrine treatment has its place mainly in the external beam radiotherapy setting. Intermittent androgen blockade is still considered experimental. The decision regarding the type of androgen deprivation should be made individually after informing the patient of all available treatment options, including watchful waiting, and on the basis of potential benefits and adverse effects. Several large studies are under way to investigate the role of adjuvant endocrine treatment in the field of early prostate cancer, intermittent androgen deprivation and endocrine therapy alone compared with endocrine therapy with radiotherapy. The real challenge, however, is to develop better means to avert hormone-refractory prostate cancer and better treatments for patients with hormone-refractory disease when it occurs.

The evolving role of estrogen therapy in prostate cancer

Estrogens, including diethylstilbestrol (DES), were used as the primary medical treatment for metastatic prostate cancer for many years but have been superceded in the past two decades by luteinizing hormone-releasing hormone (LHRH) agonists, primarily because of the cardiovascular toxicity associated with oral estrogen therapy. Recently, a renewed interest in estrogen therapy for prostate cancer in the United States has developed as a result of 3 major issues. First, when measured by declines in prostate-specific antigen of > or = 50%, clinical trials have demonstrated activity of DES, DES-diphosphate, and the estrogenic herbal therapy PC-SPES in 21%-86% of patients treated in phase II trials of androgen-independent prostate cancer patients. Second, the recent description of estrogen receptor (ER)-b has led to a reevaluation of the role of estrogens in normal prostate development and cancer pathogenesis. In contrast to ER-a, ER-b is strongly expressed in normal prostate epithelium. Furthermore, loss of ER-b expression has been demonstrated in prostate cancers, suggesting a possible role for this pathway in the development of cancer. Finally, the issues of cost and safety of estrogens are being reassessed in the current environment of rising health care costs and improved cardiovascular care. In Europe, estrogen therapy is more accepted as a low-cost and effective alternative to LHRH agonists and antiandrogens. Toxicity of DES and other estrogens has also been attenuated by strategies that use lower doses and parenteral routes of administration, thereby avoiding hepatic first-pass metabolism and decreasing the risk of thromboembolism. Nonetheless, there remain many unanswered questions about the role of estrogen therapy in prostate cancer, including differences between specific drugs, optimal dose, timing, and patient selection. Further research is needed.

Androgen receptor in prostate cancer

The normal development and maintenance of the prostate is dependent on androgen acting through the androgen receptor (AR). AR remains important in the development and progression of prostate cancer. AR expression is maintained throughout prostate cancer progression, and the majority of androgen-independent or hormone refractory prostate cancers express AR. Mutation of AR, especially mutations that result in a relaxation of AR ligand specificity, may contribute to the progression of prostate cancer and the failure of endocrine therapy by allowing AR transcriptional activation in response to antiandrogens or other endogenous hormones. Similarly, alterations in the relative expression of AR coregulators have been found to occur with prostate cancer progression and may contribute to differences in AR ligand specificity or transcriptional activity. Prostate cancer progression is also associated with increased growth factor production and an altered response to growth factors by prostate cancer cells. The kinase signal transduction cascades initiated by mitogenic growth factors modulate the transcriptional activity of AR and the interaction between AR and AR coactivators. The inhibition of AR activity through mechanisms in addition to androgen ablation, such as modulation of signal transduction pathways, may delay prostate cancer progression.

Transdermal estradiol therapy for advanced prostate cancer--forward to the past?

PURPOSE

Current hormonal therapies for prostate cancer are associated with significant morbidities, including symptoms of andropause and osteoporosis. Oral estrogens prevented many of these problems but were abandoned due to cardiovascular toxicity attributed to hepatic effect. In contrast, parenteral estrogens prevent first pass hepatic metabolism and substantially reduce cardiovascular risk, and long-term transdermal estradiol therapy is believed to be cardioprotective. We report preliminary results of a pilot study using transdermal estradiol therapy to treat men with advanced prostate cancer.

MATERIALS AND METHODS

A total of 20 patients with advanced prostate cancer were enrolled in a before and after study that examined the impact of estradiol patches on hormones, disease, thrombophilia, vascular flow, osteoporosis and quality of life.

RESULTS

Median followup is 15 months. Estradiol levels greater than 1,000 pmol./l. were achieved using 2 patches and higher levels were obtained by increasing the number of patches. All patients achieved castrate levels of testosterone within 3 weeks and had biochemical evidence of disease regression. One patient died of disease at 14 months and 1 cardiovascular complication occurred. Thrombophilic activation was avoided and vascular flow improved. Bone mineral density was significantly increased. Mild or moderate gynecomastia occurred in 80% of patients but no patient had hot flushes. All other functional and symptomatic quality of life domains improved.

CONCLUSIONS

Transdermal estradiol therapy produced an effective tumor response. Cardiovascular toxicity was substantially reduced compared with that expected of oral estrogen, and other morbidity (gynecomastia) was negligible. Transdermal estradiol therapy prevented andropause symptoms, improved quality of life scores and increased bone density. Transdermal estradiol costs a tenth of current therapy cost, with the potential for considerable economic savings over conventional hormone therapies.

Side effects of endocrine treatment and their mechanisms: castration, antiandrogens, and estrogens

Endocrine treatment of prostate cancer can be performed under several different regimes. They all have side effects which in different ways influence quality of life and the patient's general health. This paper is a survey of the most important early side effects of the different modes of endocrine treatment, their etiology, and possible ways to avoid or treat them.

Parenteral estrogen versus total androgen ablation in the treatment of advanced prostate carcinoma: effects on overall survival and cardiovascular mortality. The Scandinavian Prostatic Cancer Group (SPCG)-5 Trial Study

OBJECTIVES

To compare the effect on overall survival of total androgen ablation (TAA) with that of parenteral estrogen and to pay special attention to cardiovascular mortality. TAA (orchiectomy or a luteinizing hormone-releasing hormone analogue combined with an antiandrogen) has been proposed as superior to other endocrine treatments for patients with prostate carcinoma. Recently, the use of parenteral estrogen has been suggested to reduce or even negate the well-known cardiovascular side effects of oral estrogens.

METHODS

Nine hundred fifteen patients were randomized to intramuscular injections of 240 mg polyestradiol phosphate (PEP) every second week for the first 8 weeks (5 doses) followed by a maintenance dose of 240 mg every month (n = 458) or to bilateral orchiectomy or triptorelin 3.75 mg every month combined with the antiandrogen flutamide 250 mg three times daily. The choice between orchiectomy and triptorelin was at the discretion of the clinician and patient. Patients were stratified according to performance status, presence of cardiovascular disease, and alkaline phosphatase level. An observer totally unaware of the treatment given classified all deceased patients.

RESULTS

At a median follow-up of 18.5 months, no signs of a difference in overall survival were found between TAA and PEP (P <0.001). Of 458 patients, 266 (58.1%) had died in the PEP group compared with 269 (58.9%) of 457 patients in the TAA group. Within the TAA group, no difference in overall survival existed between patients who had undergone orchiectomy or who were given triptorelin. Furthermore, no differences in cardiovascular mortality were found (3.5% in the PEP group and 3.1% in the TAA group).

CONCLUSIONS

The current parenteral estrogen regimen seems to be of comparable efficacy and cardiovascular safety as TAA in terms of overall survival. PEP has by far the lowest drug cost and also the lowest cumulative direct costs and thus has the highest cost-effectiveness. We suggest that parenteral estrogen be included as a therapeutic option in the endocrine management of prostate carcinoma.