Effect of parenteral oestrogen on the coagulation system in patients with prostatic carcinoma

The Use of Transdermal Estrogen in Castrate-resistant, Steroid-refractory Prostate Cancer

BACKGROUND

Androgen-deprivation therapy is the mainstay of treatment for metastatic prostate cancer. Corticosteroids and estrogens are also useful agents in castration-resistant prostate cancer (CRPC). However, oral estrogens are associated with thromboembolic events, which limits their use, and transdermal estrogens may offer a safer alternative. This study was carried out to determine the safety and effectiveness of transdermal estrogens in CRPC.

PATIENTS AND METHODS

Forty-one patients with CRPC and steroid-resistant prostate cancer were eligible for this dose-escalation study of transdermal estradiol. A starting dose of 50 mcg/24 hours was applied and increased if prostate-specific antigen (PSA) rose > 5 ng/mL in steps to 300 mcg/24 hours. The primary endpoint was PSA response, and secondary outcomes included incidence of thromboembolic events and progression-free survival. Patients who progressed were offered diethylstilbestrol.

RESULTS

Five (13%) of 40 patients had > 50% PSA reduction for at least 1 month at any transdermal estradiol dose. No venous-thromboembolic events were observed, and responses plateaued at 200 mcg/24 hours. A correlation between PSA response and rising sex hormone binding globulin was seen. Fifty percent of patients subsequently responded to low-dose diethylstilbestrol.

CONCLUSION

Transdermal estradiol appears to be a low toxicity treatment option to control CRPC after failure of steroid therapy. Modulation of sex hormone binding globulin by transdermal estradiol may be one mechanism of action of estrogens on CRPC. Oral estrogens remain effective after the use of transdermal estradiol.

Estradiol for the mitigation of adverse effects of androgen deprivation therapy

Prostate cancer (PCa) is the second most commonly diagnosed cancer in men. Conventional endocrine treatment for PCa leads to global sex steroid deprivation. The ensuing severe hypogonadism is associated with well-documented adverse effects. Recently, it has become apparent that many of the biological actions attributed to androgens in men are in fact not direct, but mediated by estradiol. Available evidence supports a primary role for estradiol in vasomotor stability, skeletal maturation and maintenance, and prevention of fat accumulation. Hence there has been interest in revisiting estradiol as a treatment for PCa. Potential roles for estradiol could be in lieu of conventional androgen deprivation therapy or as low-dose add-back treatment while continuing androgen deprivation therapy. These strategies may limit some of the side effects associated with conventional androgen deprivation therapy. However, although available data are reassuring, the potential for cardiovascular risk and pro-carcinogenic effects on PCa via estrogen receptor signalling must be considered.

A Randomised Comparison Evaluating Changes in Bone Mineral Density in Advanced Prostate Cancer: Luteinising Hormone-releasing Hormone Agonists Versus Transdermal Oestradiol

Background

Luteinising hormone-releasing hormone agonists (LHRHa), used as androgen deprivation therapy (ADT) in prostate cancer (PCa) management, reduce serum oestradiol as well as testosterone, causing bone mineral density (BMD) loss. Transdermal oestradiol is a potential alternative to LHRHa.

Objective

To compare BMD change in men receiving either LHRHa or oestradiol patches (OP).

Design, setting, and participants

Men with locally advanced or metastatic PCa participating in the randomised UK Prostate Adenocarcinoma TransCutaneous Hormones (PATCH) trial (allocation ratio of 1:2 for LHRHa:OP, 2006–2011; 1:1, thereafter) were recruited into a BMD study (2006–2012). Dual-energy x-ray absorptiometry scans were performed at baseline, 1 yr, and 2 yr.

Interventions

LHRHa as per local practice, OP (FemSeven 100 μg/24 h patches).

Outcome measurements and statistical analysis

The primary outcome was 1-yr change in lumbar spine (LS) BMD from baseline compared between randomised arms using analysis of covariance.

Results and limitations

A total of 74 eligible men (LHRHa 28, OP 46) participated from seven centres. Baseline clinical characteristics and 3-mo castration rates (testosterone ≤1.7 nmol/l, LHRHa 96% [26 of 27], OP 96% [43 of 45]) were similar between arms. Mean 1-yr change in LS BMD was −0.021 g/cm³ for patients randomised to the LHRHa arm (mean percentage change −1.4%) and +0.069 g/cm³ for the OP arm (+6.0%; p < 0.001). Similar patterns were seen in hip and total body measurements. The largest difference between arms was at 2 yr for those remaining on allocated treatment only: LS BMD mean percentage change LHRHa −3.0% and OP +7.9% (p < 0.001).

Conclusions

Transdermal oestradiol as a single agent produces castration levels of testosterone while mitigating BMD loss. These early data provide further supporting evidence for the ongoing phase 3 trial.

Patient summary

This study found that prostate cancer patients treated with transdermal oestradiol for hormonal therapy did not experience the loss in bone mineral density seen with luteinising hormone-releasing hormone agonists. Other clinical outcomes for this treatment approach are being evaluated in the ongoing PATCH trial.

Trial registration

ISRCTN70406718, PATCH trial (ClinicalTrials.gov NCT00303784).

The detection of risk pathways, regulated by miRNAs, via the integration of sample-matched miRNA-mRNA profiles and pathway structure

The use of genome-wide, sample-matched miRNA (miRNAs)-mRNA expression data provides a powerful tool for the investigation of miRNAs and genes involved in diseases. The identification of miRNA-regulated pathways has been crucial for analysis of the role of miRNAs. However, the classical identification method fails to consider the structural information of pathways and the regulation of miRNAs simultaneously. We proposed a method that simultaneously integrated the change in gene expression and structural information in order to identify pathways. Our method used fold changes in miRNAs and gene products, along with the quantification of the regulatory effect on target genes, to measure the change in gene expression. Topological characteristics were investigated to measure the influence of gene products on entire pathways. Through the analysis of multiple myeloma and prostate cancer expression data, our method was proven to be effective and reliable in identifying disease risk pathways that are regulated by miRNAs. Further analysis showed that the structure of a pathway plays a crucial role in the recognition of the pathway as a factor in disease risk.

Diethylstilboestrol for the treatment of prostate cancer: past, present and future

The aim of this review was to discuss the most recent data from current trials of diethylstilboestrol (DES) to identify its present role in advanced prostate cancer treatment as new hormonal therapies emerge. The most relevant clinical studies using DES in castration-refractory prostate cancer (CRPC) were identified from the literature. The safety, efficacy, outcomes and mechanisms of action are summarized. In the age of chemotherapy this review highlights the efficacy of oestrogen therapy in CRPC. The optimal point in the therapeutic pathway at which DES should be prescribed remains to be established.

Cardiovascular outcomes in patients with locally advanced and metastatic prostate cancer treated with luteinising-hormone-releasing-hormone agonists or transdermal oestrogen: the randomised, phase 2 MRC PATCH trial (PR09)

BACKGROUND

Luteinising-hormone-releasing-hormone agonists (LHRHa) to treat prostate cancer are associated with long-term toxic effects, including osteoporosis. Use of parenteral oestrogen could avoid the long-term complications associated with LHRHa and the thromboembolic complications associated with oral oestrogen.

METHODS

In this multicentre, open-label, randomised, phase 2 trial, we enrolled men with locally advanced or metastatic prostate cancer scheduled to start indefinite hormone therapy. Randomisation was by minimisation, in a 2:1 ratio, to four self-administered oestrogen patches (100 μg per 24 h) changed twice weekly or LHRHa given according to local practice. After castrate testosterone concentrations were reached (1·7 nmol/L or lower) men received three oestrogen patches changed twice weekly. The primary outcome, cardiovascular morbidity and mortality, was analysed by modified intention to treat and by therapy at the time of the event to account for treatment crossover in cases of disease progression. This study is registered with ClinicalTrials.gov, number NCT00303784.

FINDINGS

85 patients were randomly assigned to receive LHRHa and 169 to receive oestrogen patches. All 85 patients started LHRHa, and 168 started oestrogen patches. At 3 months, 70 (93%) of 75 receiving LHRHa and 111 (92%) of 121 receiving oestrogen had achieved castrate testosterone concentrations. After a median follow-up of 19 months (IQR 12-31), 24 cardiovascular events were reported, six events in six (7·1%) men in the LHRHa group (95% CI 2·7-14·9) and 18 events in 17 (10·1%) men in the oestrogen-patch group (6·0-15·6). Nine (50%) of 18 events in the oestrogen group occurred after crossover to LHRHa. Mean 12-month changes in fasting glucose concentrations were 0·33 mmol/L (5·5%) in the LHRHa group and -0·16 mmol/L (-2·4%) in the oestrogen-patch group (p=0·004), and for fasting cholesterol were 0·20 mmol/L (4·1%) and -0·23 mmol/L (-3·3%), respectively (p<0·0001). Other adverse events reported by 6 months included gynaecomastia (15 [19%] of 78 patients in the LHRHa group vs 104 [75%] of 138 in the oestrogen-patch group), hot flushes (44 [56%] vs 35 [25%]), and dermatological problems (10 [13%] vs 58 [42%]).

INTERPRETATION

Parenteral oestrogen could be a potential alternative to LHRHa in management of prostate cancer if efficacy is confirmed. On the basis of our findings, enrolment in the PATCH trial has been extended, with a primary outcome of progression-free survival.

FUNDING

Cancer Research UK, MRC Clinical Trials Unit.

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.

Significance of pretreatment cardiovascular morbidity as a risk factor during treatment with parenteral oestrogen or combined androgen deprivation of 915 patients with metastasized prostate cancer: evaluation of cardiovascular events in a randomized trial

OBJECTIVE

This study aimed to evaluate prognostic risk factors for cardiovascular events during treatment of metastatic prostate cancer patients with high-dose parenteral polyoestradiol phosphate (PEP, Estradurin®) or combined androgen deprivation (CAD) with special emphasis on pretreatment cardiovascular disease.

MATERIAL AND METHODS

Nine-hundred and fifteen patients with T0-4, Nx, M1, G1-3, hormone- naïve prostate cancer were randomized to treatment with PEP 240 mg i.m. twice a month for 2 months and thereafter monthly, or to flutamide (Eulexin®) 250 mg per os three times daily in combination with either triptorelin (Decapeptyl®) 3.75 mg i.m. per month or on an optional basis with bilateral orchidectomy. Pretreatment cardiovascular morbidity was recorded and cardiovascular events during treatment were assessed by an experienced cardiologist. A multivariate analysis was done using logistic regression.

RESULTS

There was a significant increase in cardiovascular events during treatment with PEP in patients with previous ischaemic heart disease (p = 0.008), ischaemic cerebral disease (p = 0.002), intermittent claudication (p = 0.031) and especially when the whole group of patients with pretreatment cardiovascular diseases was analysed together (p < 0.001). In this group 33% of the patients had a cardiovascular event during PEP treatment. In the multivariate analysis PEP stood out as the most important risk factor for cardiac complications (p = 0.029). Even in the CAD group there was a significant increase in cardiovascular events in the group with all previous cardiovascular diseases taken together (p = 0.036).

CONCLUSIONS

Patients with previous cardiovascular disease are at considerable risk of cardiovascular events during treatment with high-dose PEP and even during CAD therapy. Patients without pretreatment cardiovascular morbidity have a moderate cardiovascular risk during PEP treatment and could be considered for this treatment if the advantages of this therapy, e.g. avoidance of osteopenia and hot flushes and the low price, are given priority.

Circulating concentrations of hemostatic factors and two "steroid sensitive proteins" during oral hormone replacement therapy in women with coronary heart disease

OBJECTIVE

To study a possible use of sex hormone-binding globulin (SHBG) and corticosteroid-binding globulin (CBG) as markers for changes in hemostatic factors during oral postmenopausal hormone replacement therapy (HRT).

METHODS

Twenty-eight postmenopausal women were treated with oral conjugated equine estrogens+oral medroxyprogesterone acetate (CEE + MPA, n = 15) or with placebo (n = 13). Serum SHBG, CBG, testosterone, cortisol and plasma coagulation factors, coagulation inhibitors and markers of coagulation activation were measured before and after 6 and 12 months of treatment.

RESULTS

Pretreatment plasminogen activator inhibitor 1 (PAI-1) levels correlated negatively to SHBG and antithrombin III (AT III) negatively to total and free cortisol. In the CEE + MPA group, CBG, SHBG and Factor VII increased, and PAI-1, AT III and free testosterone decreased during treatment. No significant changes were found in plasma von Willebrand factor antigen, thrombin-antithrombin complex, fibrin D-dimer and fibrinogen. A significant, negative correlation was found between changes in SHBG and PAI-1. No changes were found in the placebo group.

CONCLUSION

The only correlation found between changes in "steroid sensitive" proteins and hemostatic factors was between increased SHBG and a possibly beneficial effect of estrogens, i.e. decreased PAI-1 values. SHBG or CBG could not be used as predictors of increased cardiovascular risk during postmenopausal oral HRT.

Parenteral estrogen versus combined androgen deprivation in the treatment of metastatic prostatic cancer: part 2. Final evaluation of the Scandinavian Prostatic Cancer Group (SPCG) Study No. 5

OBJECTIVE

To compare parenteral estrogen therapy in the form of high-dose polyestradiol phosphate (PEP; Estradurin) with combined androgen deprivation (CAD) in the treatment of prostate cancer patients with skeletal metastases. The aim of the study was to compare anticancer efficacy and adverse events, especially cardiovascular events.

MATERIAL AND METHODS

In total, 910 eligible patients with T0-4, NX, M1, G1-3 prostate cancer with an Eastern Cooperative Oncology Group performance status of 0-2 were randomized to treatment with either PEP 240 mg i.m. twice a month for 2 months and thereafter monthly, or flutamide (Eulexin) 250 mg t.i.d. per os in combination with either triptorelin (Decapeptyl) 3.75 mg i.m. per month or on an optional basis bilateral orchidectomy.

RESULTS

At this final evaluation of the trial 855 of the 910 patients were dead. There was no difference between the treatment groups in terms of biochemical or clinical progression-free survival or in overall or disease-specific survival. There was no difference in cardiovascular mortality, but a significant increase in non-fatal cardiovascular events in the PEP arm (p<0.05) predominantly caused by an increase in ischemic heart and heart decompensation events. There were 18 grave skeletal events in the CAD group but none in the PEP group (p=0.001).

CONCLUSIONS

PEP has an anticancer efficacy equal to CAD and does not increase cardiovascular mortality in metastasized patients, but carries a significant risk of non-fatal cardiovascular events, which should be balanced against the skeletal complications in the CAD group. It is feasible to use Estradurin in the primary or secondary endocrine treatment of metastasized patients without prominent cardiac risk factors and especially those with osteoporosis.

Parenteral Estrogens for Prostate Cancer: Can a New Route of Administration Overcome Old Toxicities?

Androgen deprivation therapy (ADT) is the mainstay of management of advanced-stage prostate cancer and recently has been shown to improve survival when administered in earlier stages of the disease. The oncologic benefits of ADT might be partially offset, however, by a reduction in quality of life because of adverse effects. In addition to the well-recognized adverse consequences of ADT, recent evidence suggests that ADT is associated with dyslipidemia, impaired glucose metabolism, adverse body compositional changes, and osteoporosis. Therefore, there is a pressing need to develop less toxic forms of ADT. A novel approach to this problem is the use of estrogen to induce androgen suppression. Whereas oral estrogen therapy is known to be associated with thromboembolic complications, studies of parenteral estrogen in men with prostate cancer suggest that the use of parenteral estrogen achieves target androgen suppression, does not adversely affect prothrombotic protein levels, and is not associated with adverse metabolic, skeletal, and body compositional changes when compared with conventional ADT. Herein, we review the data for parenteral estrogen use in prostate cancer, the antineoplastic mechanisms of action of estrogen in prostate cancer, the potential advantages of parenteral estrogen compared with conventional ADT, and the remaining barriers in the use of parenteral estrogen in prostate cancer.

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.

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.

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.

Effects of transdermal estrogen on levels of lipids, lipase activity, and inflammatory markers in men with prostate cancer

Androgen deprivation therapy (ADT) for prostate cancer is now used in earlier disease stages and as adjuvant treatment. Recognizing and reducing the toxicity of this therapy, including worsened lipid levels and cardiovascular disease (CVD) risks, has become an important clinical concern. Oral estrogen therapy induces hypogonadism and mitigates many side effects of ADT, but has a high thrombosis risk. Transdermal estrogen therapy (TDE) has a lower thrombosis risk than oral estrogen and may improve CVD risk compared with ADT. This prospective pilot study of 18 men with androgen-independent prostate cancer receiving ADT measured effects of TDE on lipid and inflammatory CVD risk factors before and after 8 weeks of TDE (estradiol 0.6 mg/day). During treatment, estradiol levels rose 17-fold; total cholesterol, LDL cholesterol, and apolipoprotein B levels decreased. HDL2 cholesterol increased, with no changes in triglyceride or VLDL cholesterol levels. Dense LDL cholesterol decreased and LDL buoyancy increased in association with a decrease in HL activity. Highly sensitive C-reactive protein levels and other inflammatory markers did not worsen. Compared with ADT, short-term TDE therapy of prostate cancer improves lipid levels without deterioration of CVD-associated inflammatory markers and may, on longer-term follow-up, improve CVD and mortality rates.

TRANSDERMAL ESTRADIOL THERAPY FOR PROSTATE CANCER REDUCES THROMBOPHILIC ACTIVATION AND PROTECTS AGAINST THROMBOEMBOLISM

PURPOSE

Oral estrogens were an effective treatment for prostate cancer but were abandoned because of an increased risk of cardiovascular toxicity and particularly thromboembolism. We have recently shown that transdermal estradiol produces an effective tumor response and negligible cardiovascular toxicity. Here we report the influence of transdermal estradiol therapy on the coagulation profile of men with advanced prostate cancer.

MATERIALS AND METHODS

A total of 20 patients with newly diagnosed locally advanced or metastatic prostate cancer were treated using transdermal estradiol patches and the coagulation profile was assessed before and during 12 months therapy. Activation of coagulation was assessed by assaying the levels of activated factor VII (VIIa), activated factor XII (XIIa), prothrombin fragments 1 and 2 (F1 + 2), thrombin-antithrombin III (TAT III) complex and fibrinogen. Inhibition of the coagulation cascade was assayed by protein C, protein S and activated protein C resistance (APC-R). Fibrinolytic activity was determined by assaying tissue plasminogen activator (TPA) and plasminogen activation inhibitor type 1 (PAI-1). D-Dimer levels assessed both coagulation and fibrinolytic (thrombophilic) activity. Venous Duplex, color Doppler ultrasound and photoplethysmography were used to assess for thrombosis.

RESULTS

Levels of VIIa and XIIa were unaffected by transdermal estradiol therapy. Although levels of TAT III were increased in some patients at 12 months, the increase was markedly less than that observed historically with equivalent doses of oral estrogens. Levels of the inhibitory and fibrinolytic factors including protein C, protein S, APC-R, TPA and PAI-1 remained stable. Reductions in F1+F2, fibrinogen and D-Dimer levels represented a normalization from increased levels to the physiological range.

CONCLUSIONS

These results suggest that transdermal estradiol reduces thrombophilic activation in men with advanced prostate cancer, and protects against the risk of thrombosis.

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.

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.

Potential side-effects of endocrine treatment of long duration in prostate cancer

Endocrine treatment of prostate cancer has been established for more than 5 decades. Focusing on immediate or short-term side effects, bilateral orchidectomy may cause psychological trauma, treatment with oral estrogens is combined with a high risk of severe cardiovascular complications, and the use of LH-RH agonists and antiandrogens as monotherapies or in combination may result in tumor flare, hot flashes, and gynecomastia. In recent years an increasing number of reports on anemia and/or osteoporosis related to endocrine treatment have been published. These side effects are regular and persistent after orchidectomy, or during treatment with LH-RH agonists, and are most often expressed with maximum androgen blockade. In contrast, anemia and/or osteoporosis are not reported with estrogen treatment or the use of nonsteroidal antiandrogens as a monotherapy regimen. Since many prostate cancer patients are treated hormonally for many years, control of Hb levels and bone mineral density before and after initiation of treatment at regular intervals is highly recommended as a standard of care.

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.

Time for revival of estrogens in the treatment of advanced prostatic carcinoma? Pharmacokinetics, and endocrine and clinical effects, of a parenteral estrogen regimen

BACKGROUND

The present pilot study tested the clinical performance of a new pharmacokinetically guided dosing regimen of parenteral estrogen in patients with advanced prostatic carcinoma. The aim was to accelerate endocrine effects and to avoid cardiovascular side effects.

METHODS

Seventeen patients were randomized to intramuscular injections of 240 mg polyestradiol phosphate (PEP) every second week for the first 8 weeks (five doses), followed by a maintenance dose of 240 mg every month; and 16 patients were randomized to bilateral orchidectomy. The estrogen dosing was calculated by pharmacokinetic modelling to achieve a rapid increase in serum estradiol and thereby a fast decrease in testosterone.

RESULTS

The predicted increment in serum estrogen was achieved, together with a subsequent decrease in testosterone in the PEP group. In addition, there were no signs of an increased cardiovascular morbidity. This was probably due to a minimal estrogenic influence on the liver and was reflected by unchanged levels of coagulation factor VII. Clinical effects, during the first 2 years of treatment, were similar in the two treatment arms, with 12 patients in the orchidectomy group and 14 patients in the PEP group responding to treatment.

CONCLUSIONS

The present parenteral regimen is an efficient and time-saving estrogen regimen with a favorable side-effect profile. PEP seems to offer a potential for revival of the most cost-effective endocrine treatment of cancer of the prostate, i.e., estrogen.

Possible bone-preserving capacity of high-dose intramuscular depot estrogen as compared to orchidectomy in the treatment of patients with prostatic carcinoma

BACKGROUND

Treatment of prostatic disease with GnRH agonists or by orchidectomy affects bone mass negatively. Estrogen treatment has beneficial effects on bone mass in women and might hypothetically have a bone preserving capacity also in patients with prostatic cancer.

METHODS

We followed serum markers for bone and collagen metabolism and sex steroids for 18 months in patients with prostatic cancer treated by orchidectomy (N = 13) or by single-drug parenteral polyestradiol phosphate (240 mg intramuscularly every second week for the first two months, and then every fourth week; N = 17).

RESULTS

Total and free testosterone reached castration levels within 1.5 months of estrogen treatment. Four patients developing progressive disease and/or signs of metastasis were excluded from the analysis. In the remaining patients, serum osteocalcin, procollagen IIIP (PIIINP), procollagen (PICP), and the crosslinked carboxyterminal telopeptide of type I collagen (ICTP) increased significantly over time following orchidectomy (N = 11). Serum osteocalcin and PICP decreased significantly over time during estrogen treatment (N = 15). Treatment values of all four markers were significantly lower in estrogen-treated than in orchidectomized patients.

CONCLUSIONS

The changes in serum bone and collagen markers indicate an increased bone turnover in orchidectomized subjects. The opposite pattern was found in the estrogen-treated patients, indicating a reduced turnover. Estrogens may also have a bone mass-preserving capacity in elderly males with prostatic cancer.

Pharmacokinetics and testosterone suppression of a single dose of polyestradiol phosphate (Estradurin) in prostatic cancer patients

The pharmacokinetics and endocrine effects of polyestradiol phosphate (PEP; Estradurin) were studied by determination of the concentrations of estradiol (E2), unconjugated (E1) and total estrone (tE1; > or = 85% estrone sulfate), and testosterone in serum from 11 prostatic cancer patients after administration of a single intramuscular injection (320 mg). After injection of PEP, serum concentrations of E2, E1, and tE1 increased during 2-3 weeks. Thereafter serum E2 declined monophasically with a mean half-life of 70 days. The elimination of E1 and tE1 seemed to be governed by the formation of E2. The testosterone concentration decreased inversely to the raising E2 level and reached castration levels within 3 weeks and remained at this level for about 2 weeks, whereafter it increased inversely to the decreasing E2 concentrations.

Bone mineral density in patients with prostatic cancer treated with orchidectomy and with estrogens

Bone mineral density (BMD) and bone mineral content (BMC) were measured in the femoral neck area, trochanteric area and Wards triangle, and in the distal radius of the left forearm before and after 1 year of endocrine treatment in 27 patients with prostatic cancer. Eleven of the patients were treated with orchidectomy and 16 with combined oral and intramuscular estrogens. The patients were free from metastases during the entire observation period. In the orchidectomized patients, BMD and BMC of the distal radius decreased significantly following treatment, whereas no changes were observed in the estrogen-treated patients. These preliminary results demonstrate that estrogens may protect bone in male subjects also and may merit further investigations on larger groups of patients.

Comparison of a long-acting LHRH agonist and polyoestradiol phosphate in the treatment of advanced prostatic carcinoma. An open prospective, randomized multicentre study

In a prospective, randomized open study, a long-acting LHRH agonist (Zoladex) was compared with polyoestradiol phosphate (Estradurin), both widely used in Finland for palliative treatment of prostatic carcinoma, as regards efficacy and side effects. Of the 236 enrolled patients, 129 were randomized to receive LHRH agonist and 107 to oestrogen treatment. The median follow-up was 25 months. Reduction of prostatic volume was quicker and more effective in the LHRH than in the oestrogen group, and serum testosterone concentrations fell to castration level after 1 month and 1 year, respectively. In locally advanced (M0) and histologically well or moderately differentiated tumours, LHRH agonist therapy was considerably more effective than oestrogen as regards time to progression of the carcinoma, but in metastatic (M1) and histologically poorly differentiated tumours both methods gave similar results. Cardiovascular complications showed equal incidence in both groups. LHRH agonist therapy thus seemed to be more effective than polyoestradiol phosphate against locally advanced prostatic cancer in the doses used.

Relapse on endocrine treatment in patients with stage D2 prostate cancer. Does second-line hormonal therapy affect survival?

Patients with Stage D2 prostate cancer relapsing on endocrine treatment have a grim prognosis. The role of a second-line hormonal treatment is debatable. We analyzed retrospectively, response and survival among 119 men (57 black, 62 white) progressing on a variety of first-line hormonal therapy. Sixty-one received a second-line hormonal treatment. Fifty-eight received only supportive therapy after first line therapy was discontinued. Age and race were not a factor in survival. Based on this retrospective study the optimal management for progressive metastatic prostate cancer cannot be delineated. However, the best results were in patients treated with diethylstilbestrol (DES) as a single treatment or when employed as either first or second treatment in patients receiving two therapies. The other modalities, e.g., bilateral orchiectomy, LH-RH analogues, and anti-androgens resulted in comparable outcomes when used either as single treatment or in combinations. Further clarification of the trends shown in this report require randomized controlled studies.

Cost comparison of parenteral estrogen and conventional hormonal treatment in patients with prostatic cancer

The present study compares the cost of antitumor therapy and adverse cardiovascular effects during the first year of treatment with oral estrogens, nonoral estrogens, or surgical castration in patients with prostatic cancer. We found a much higher cost for patients treated with orchidectomy and oral estrogens than for patients treated with nonoral estrogens. Twenty-five percent of the patients treated with oral estrogen suffered cardiovascular complications, compared to none of the patients treated by orchidectomy or nonoral estrogens. The initial cost of orchidectomy as compared to nonoral estrogen treatment was shown not be balanced within the expected survival time of patients with advanced prostatic cancer. Furthermore, surgical castration causes psychological trauma to the patient. We recommend parenteral estrogen therapy as a low-cost therapeutic regimen in patients with prostatic cancer.