A controlled trial of leuprolide with and without flutamide in prostatic carcinoma

To test the hypothesis that maximal androgen blockade improves the effectiveness of the treatment of prostatic cancer, we conducted a randomized, double-blind trial in patients with disseminated, previously untreated prostate cancer (stage D2). All 603 men received leuprolide, an analogue of gonadotropin-releasing hormone that inhibits the release of gonadotropins, in combination with either placebo or flutamide, a nonsteroidal antiandrogen that inhibits the binding of androgens to the cell nucleus. As compared with the 300 patients receiving leuprolide and placebo, the 303 patients randomly assigned to receive leuprolide and flutamide had a longer progression-free survival (16.5 vs. 13.9 months; P = 0.039) and an increase in the median length of survival (35.6 vs. 28.3 months; P = 0.035). The differences between the treatments were particularly evident for men with minimal disease and good performance status; however, further studies should be conducted in this subgroup. Symptomatic improvement was greatest during the first 12 weeks of the combined androgen blockade, when leuprolide alone often produces a painful flare in the disease. We conclude that in patients with advanced prostate cancer, treatment with leuprolide and flutamide is superior to treatment with leuprolide alone.

Duration of androgen suppression in the treatment of prostate cancer

BACKGROUND

The combination of radiotherapy plus long-term medical suppression of androgens (> or = 2 years) improves overall survival in patients with locally advanced prostate cancer. We compared the use of radiotherapy plus short-term androgen suppression with the use of radiotherapy plus long-term androgen suppression in the treatment of locally advanced prostate cancer.

METHODS

We randomly assigned patients with locally advanced prostate cancer who had received external-beam radiotherapy plus 6 months of androgen suppression to two groups, one to receive no further treatment (short-term suppression) and the other to receive 2.5 years of further treatment with a luteinizing hormone-releasing hormone agonist (long-term suppression). An outcome of noninferiority of short-term androgen suppression as compared with long-term suppression required a hazard ratio of more than 1.35 for overall survival, with a one-sided alpha level of 0.05. An interim analysis showed futility, and the results are presented with an adjusted one-sided alpha level of 0.0429.

RESULTS

A total of 1113 men were registered, of whom 970 were randomly assigned, 483 to short-term suppression and 487 to long-term suppression. After a median follow-up of 6.4 years, 132 patients in the short-term group and 98 in the long-term group had died; the number of deaths due to prostate cancer was 47 in the short-term group and 29 in the long-term group. The 5-year overall mortality for short-term and long-term suppression was 19.0% and 15.2%, respectively; the observed hazard ratio was 1.42 (upper 95.71% confidence limit, 1.79; P=0.65 for noninferiority). Adverse events in both groups included fatigue, diminished sexual function, and hot flushes.

CONCLUSIONS

The combination of radiotherapy plus 6 months of androgen suppression provides inferior survival as compared with radiotherapy plus 3 years of androgen suppression in the treatment of locally advanced prostate cancer. (ClinicalTrials.gov number, NCT00003026.)

Endocrine treatment, with or without radiotherapy, in locally advanced prostate cancer (SPCG-7/SFUO-3): an open randomised phase III trial

BACKGROUND

Several studies have shown the efficacy of endocrine therapy in combination with radiotherapy in high-risk prostate cancer. To assess the effect of radiotherapy, we did an open phase III study comparing endocrine therapy with and without local radiotherapy, followed by castration on progression.

METHODS

This randomised trial included men from 47 centres in Norway, Sweden, and Denmark. Between February, 1996, and December, 2002, 875 patients with locally advanced prostate cancer (T3; 78%; PSA<70; N0; M0) were centrally randomly assigned by computer to endocrine treatment alone (3 months of total androgen blockade followed by continuous endocrine treatment using flutamide; 439 patients), or to the same endocrine treatment combined with radiotherapy (436 patients). The primary endpoint was prostate-cancer-specific survival, and analysis was by intention to treat. This study is registered as an international standard randomised controlled trial, number ISRCTN01534787.

FINDINGS

After a median follow-up of 7.6 years, 79 men in the endocrine alone group and 37 men in the endocrine plus radiotherapy group had died of prostate cancer. The cumulative incidence at 10 years for prostate-cancer-specific mortality was 23.9% in the endocrine alone group and 11.9% in the endocrine plus radiotherapy group (difference 12.0%, 95% CI 4.9-19.1%), for a relative risk of 0.44 (0.30-0.66). At 10 years, the cumulative incidence for overall mortality was 39.4% in the endocrine alone group and 29.6% in the endocrine plus radiotherapy group (difference 9.8%, 0.8-18.8%), for a relative risk of 0.68 (0.52-0.89). Cumulative incidence at 10 years for PSA recurrence was substantially higher in men in the endocrine-alone group (74.7%vs 25.9%, p<0.0001; HR 0.16; 0.12-0.20). After 5 years, urinary, rectal, and sexual problems were slightly more frequent in the endocrine plus radiotherapy group.

INTERPRETATION

In patients with locally advanced or high-risk local prostate cancer, addition of local radiotherapy to endocrine treatment halved the 10-year prostate-cancer-specific mortality, and substantially decreased overall mortality with fully acceptable risk of side-effects compared with endocrine treatment alone. In the light of these data, endocrine treatment plus radiotherapy should be the new standard.

Bilateral orchiectomy with or without flutamide for metastatic prostate cancer

BACKGROUND

Combined androgen blockade for the treatment of metastatic prostate cancer consists of an antiandrogen drug plus castration. In a previous trial, we found that adding the antiandrogen flutamide to leuprolide acetate (a synthetic gonadotropin-releasing hormone that results in medical ablation of testicular function) significantly improved survival as compared with that achieved with placebo plus leuprolide acetate. In the current trial, we compared flutamide plus bilateral orchiectomy with placebo plus orchiectomy.

METHODS

We randomly assigned patients who had never received antiandrogen therapy and who had distant metastases from adenocarcinoma of the prostate to treatment with bilateral orchiectomy and either flutamide or placebo. Patients were stratified according to the extent of disease and according to performance status.

RESULTS

Of the 1387 patients who were enrolled in the trial, 700 were randomly assigned to the flutamide group and 687 to the placebo group. Overall, the incidence of toxic effects was minimal; the only notable differences between the groups were the greater rates of diarrhea and anemia with flutamide. There was no significant difference between the two groups in overall survival (P=0.14). The estimated risk of death (hazard ratio) for flutamide as compared with placebo was 0.91 (90 percent confidence interval, 0.81 to 1.01). Flutamide was not associated with enhanced benefit in patients with minimal disease.

CONCLUSIONS

The addition of flutamide to bilateral orchiectomy does not result in a clinically meaningful improvement in survival among patients with metastatic prostate cancer.

6-month androgen suppression plus radiation therapy vs radiation therapy alone for patients with clinically localized prostate cancer: a randomized controlled trial

CONTEXT

Survival benefit in the management of high-grade clinically localized prostate cancer has been shown for 70 Gy radiation therapy combined with 3 years of androgen suppression therapy (AST), but long-term AST is associated with many adverse events.

OBJECTIVE

To assess the survival benefit of 3-dimensional conformal radiation therapy (3D-CRT) alone or in combination with 6 months of AST in patients with clinically localized prostate cancer.

DESIGN, SETTING, AND PATIENTS

A prospective randomized controlled trial of 206 patients with clinically localized prostate cancer who were randomized to receive 70 Gy 3D-CRT alone (n = 104) or in combination with 6 months of AST (n = 102) from December 1, 1995, to April 15, 2001. Eligible patients included those with a prostate-specific antigen (PSA) of at least 10 ng/mL, a Gleason score of at least 7, or radiographic evidence of extraprostatic disease.

MAIN OUTCOME MEASURES

Time to PSA failure (PSA >1.0 ng/mL and increasing >0.2 ng/mL on 2 consecutive visits) and overall survival.

RESULTS

After a median follow-up of 4.52 years, patients randomized to receive 3D-CRT plus AST had a significantly higher survival (P =.04), lower prostate cancer-specific mortality (P =.02), and higher survival free of salvage AST (P =.002). Kaplan-Meier estimates of 5-year survival rates were 88% (95% confidence interval [CI], 80%-95%) in the 3D-CRT plus AST group vs 78% (95% CI, 68%-88%) in the 3D-CRT group. Rates of survival free of salvage AST at 5 years were 82% (95% CI, 73%-90%) in the 3D-CRT plus AST group vs 57% (95% CI, 46%-69%) in the 3D-CRT group.

CONCLUSION

The addition of 6 months of AST to 70 Gy 3D-CRT confers an overall survival benefit for patients with clinically localized prostate cancer.

Phase III radiation therapy oncology group (RTOG) trial 86-10 of androgen deprivation adjuvant to definitive radiotherapy in locally advanced carcinoma of the prostate

PURPOSE

To test the hypothesis that androgen ablation before and during radiotherapy for locally advanced carcinoma of the prostate may, by reducing tumor bulk and enhancing tumor cell kill, improve locoregional control and ultimately survival.

METHODS AND MATERIALS

The study was conducted from 1987 to 1991. Eligible patients were those with bulky tumors (T2--T4) with or without pelvic lymph node involvement and without evidence of distant metastases. They were randomized to receive goserelin, 3.6 mg every 4 weeks; and flutamide, 250 mg t.i.d. for 2 months before radiation therapy and during radiation therapy (Arm I), or radiation therapy alone (Arm II). Of 471 randomized patients, 456 were evaluable: 226 on Arm I and 230 on Arm II.

RESULTS

As of November 1999, the median follow-up has reached 6.7 years for all patients and 8.6 years for alive patients. At 8 years, androgen ablation has been associated with an improvement in local control (42% vs. 30%, p = 0.016), reduction in the incidence of distant metastases (34% vs. 45%, p = 0.04), disease-free survival (33% vs. 21%, p = 0.004), biochemical disease-free survival = PSA <1.5 (24% vs. 10%, p < 0.0001), and cause-specific mortality (23% vs. 31%, p = 0.05). However, subset analysis indicates that the beneficial effect of short-term androgen ablation appears preferentially in patients with Gleason score 2--6. In that population, there is a highly significant improvement in all endpoints, including survival (70% vs. 52%, p = 0.015). In patients with Gleason 7--10 tumors, the regimen has not resulted in a significant enhancement in either locoregional control or survival.

CONCLUSION

In patients with Gleason score 2--6 carcinoma of the prostate, a short course of androgen ablation administered before and during radiotherapy has been associated with a highly significant improvement in local control, reduction in disease progression, and overall survival.

Gene expression analysis of human prostate carcinoma during hormonal therapy identifies androgen-responsive genes and mechanisms of therapy resistance

The androgen-signaling pathway is critical to the development and progression of prostate cancer and androgen ablation is a mainstay of therapy for this disease. We performed a genome-wide expression analysis of human prostate cancer during androgen ablation therapy to identify genes regulated by androgen and genes differentially expressed after the development of resistance. Six hundred and fifty-four of 63,175 probe sets detected significant expression changes after 3 months of treatment with goserelin and flutamide. This included 149 genes that were also differentially expressed 36 hours after androgen withdrawal in LNCaP cells. These genes reflect the physiological changes that occur in treated tumors and include potential direct targets of the androgen receptor. Expression profiles of androgen ablation-resistant tumors demonstrated that many of the gene expression changes detected during therapy were no longer present suggesting a reactivation of the androgen response pathway in the absence of exogenous hormone. Therapy resistance was associated with differential expression of a unique set of genes that reflect potential mechanisms of reactivation. Specifically an up-regulation of the androgen receptor and key enzymes for steroid biosynthesis suggest that resistant tumors have increased sensitivity to and endogenous synthesis of androgenic hormones. The specific pathways of reactivation provide opportunities for classification of resistant tumors and targeted therapies.

Androgen suppression and radiation vs radiation alone for prostate cancer: a randomized trial

CONTEXT

Comorbidities may increase the negative effects of specific anticancer treatments such as androgen suppression therapy (AST).

OBJECTIVES

To compare 6 months of AST and radiation therapy (RT) to RT alone and to assess the interaction between level of comorbidity and all-cause mortality.

DESIGN, SETTING, AND PATIENTS

At academic and community-based medical centers in Massachusetts, between December 1, 1995, and April 15, 2001, 206 men with localized but unfavorable-risk prostate cancer were randomized to receive RT alone or RT and AST combined. All-cause mortality estimates stratified by randomized treatment group and further stratified in a postrandomization analysis by the Adult Comorbidity Evaluation 27 comorbidity score were compared using a log-rank test.

MAIN OUTCOME MEASURE

Time to all-cause mortality.

RESULTS

As of January 15, 2007, with a median follow-up of 7.6 (range, 0.5-11.0) years, 74 deaths have occurred. A significant increase in the risk of all-cause mortality (44 vs 30 deaths; hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.1-2.9; P = .01) was observed in men randomized to RT compared with RT and AST. However, the increased risk in all-cause mortality appeared to apply only to men randomized to RT with no or minimal comorbidity (31 vs 11 deaths; HR, 4.2; 95% CI, 2.1-8.5; P < .001). Among men with moderate or severe comorbidity, those randomized to RT alone vs RT and AST did not have an increased risk of all-cause mortality (13 vs 19 deaths; HR, 0.54; 95% CI, 0.27-1.10; P = .08).

CONCLUSIONS

The addition of 6 months of AST to RT resulted in increased overall survival in men with localized but unfavorable-risk prostate cancer. This result may pertain only to men without moderate or severe comorbidity, but this requires further assessment in a clinical trial specifically designed to assess this interaction.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00116220.

Androgen deprivation with radiation therapy compared with radiation therapy alone for locally advanced prostatic carcinoma: a randomized comparative trial of the Radiation Therapy Oncology Group

OBJECTIVES

Androgen deprivation therapy before and during radiation therapy could, by reducing tumor volume, increase local tumor control, disease-free survival, and overall survival in patients with locally advanced adenocarcinomas of the prostate.

METHODS

In a randomized controlled clinical trial, patients with large T2, T3, and T4 prostate tumors, but no evidence of osseous metastasis, were randomized to receive goserelin 3.6 mg subcutaneously every 4 weeks and flutamide 250 mg orally three times daily 2 months before and during the radiation therapy course (Arm I) compared with radiation therapy alone (Arm II). Pelvic irradiation was administered with 1.8 to 2.0 Gy per day to a total dose of 45 +/- 1 Gy followed by a boost to the prostate target volume to a total dose of 65 to 70 Gy.

RESULTS

Of 471 randomized patients, 456 were evaluable, 226 on Arm I and 230 on Arm II. With a median potential follow-up of 4.5 years, the cumulative incidence of local progression at 5 years was 46% in Arm I and 71% in Arm II (P < 0.001). The 5-year incidence of distant metastasis on Arms I and II was 34% and 41%, respectively (P = 0.09). Progression-free survival rates including normal prostate-specific antigen (PSA) levels for 396 patients with at least one PSA recorded were 36% in Arm I and 15% in Arm II at 5 years (P < 0.001). At this time, no significant difference in overall survival could be detected (P = 0.7).

CONCLUSIONS

Short-term androgen deprivation with radiation therapy results in a marked increase in local control and disease-free survival compared with pelvic irradiation alone in patients with locally advanced carcinoma of the prostate. Long-term surveillance is required to assess effects on overall survival.

T cell infiltration of the prostate induced by androgen withdrawal in patients with prostate cancer

Manipulations capable of breaking host tolerance to induce tissue-specific T cell-mediated inflammation are of central importance to tumor immunotherapy and our understanding of autoimmunity. We demonstrate that androgen ablative therapy induces profuse T cell infiltration of benign glands and tumors in human prostates. T cell infiltration is readily apparent after 7-28 days of therapy and is comprised predominantly of a response by CD4+ T cells and comparatively fewer CD8+ T cells. Also, T cells within the treated prostate exhibit restricted TCR Vbeta gene usage, consistent with a local oligoclonal response. Recruitment/activation of antigen-presenting cells in treated prostate tissues may contribute to local T cell activation. The induction of T cell infiltration in prostate tissues treated with androgen ablation may have implications for the immunotherapeutic treatment of prostate cancer as well as other hormone-sensitive malignancies, including breast carcinoma.

Short-term androgen deprivation and radiotherapy for locally advanced prostate cancer: results from the Trans-Tasman Radiation Oncology Group 96.01 randomised controlled trial

BACKGROUND

Androgen deprivation is an established treatment regimen for disseminated prostate cancer; however, its role in patients with localised cancer is less clear. We did a large randomised controlled trial to determine whether 3 months or 6 months of androgen deprivation given before and during radiotherapy improves outcomes for patients with locally advanced prostate cancer.

METHODS

818 men with locally advanced prostate cancer were randomly assigned to: no androgen deprivation (ie, radiotherapy alone: 66 Gy in 33 fractions of 2 Gy per day over 6.5-7.0 weeks to the prostate and seminal vesicles); 3 months' androgen deprivation with 3.6 mg goserelin given subcutaneously every month and 250 mg flutamide given orally three times a day starting 2 months before radiotherapy (same regimen as control group); or 6 months' androgen deprivation, with the same regimen, starting 5 months before radiotherapy (same regimen as control group). Primary endpoints were time to local failure and prostate-cancer-specific survival; secondary endpoints were distant failure, disease-free survival, and freedom from salvage treatment. Analyses were done by intention to treat.

FINDINGS

802 (98%) patients were eligible for analysis. Median follow-up was 5.9 years (range 0.1-8.5). Compared with patients assigned no androgen deprivation, those assigned 3 months' treatment had significantly improved local failure (hazard ratio [HR] 0.56 [95% CI 0.39-0.79], p=0.001), biochemical failure-free survival (0.70 [0.56-0.88], p=0.002), disease-free survival (0.65 [0.52-0.80], p=0.0001), and freedom from salvage treatment (0.73 [0.56-0.96], p=0.025). 6 months' androgen deprivation significantly improved local failure (0.42 [0.28-0.62], p<0.0001), biochemical failure-free survival (0.58 [0.46-0.74], p<0.0001), disease-free survival (0.56 [0.45-0.69], p<0.0001), freedom from salvage treatment (0.53 [0.40-0.71], p<0.0001), distant failure (0.67 [0.45-0.99], p=0.046) and prostate-cancer-specific survival (0.56 [0.32-0.98], p=0.04) compared with no androgen deprivation.

INTERPRETATION

6 months' androgen deprivation given before and during radiotherapy improves the outlook of patients with locally advanced prostate cancer. Further follow-up is needed to estimate precisely the size of survival benefits. Increased radiation doses and additional periods of androgen deprivation might lead to further benefit.

Flutamide withdrawal syndrome: its impact on clinical trials in hormone-refractory prostate cancer

PURPOSE

To evaluate the effect of discontinuation of the antiandrogen, flutamide, in patients with metastatic prostate cancer who are progressing on hormonal therapy.

PATIENTS AND METHODS

Thirty-six patients with progressive disease on hormonal treatment that included flutamide had discontinuation of the antiandrogen. Thirty-five (95%) had progressive increases in prostate-specific antigen (PSA) levels, despite castrate levels of testosterone. Twenty-five patients (69%) were treated with combined androgen blockade (orchiectomy or gonadotropin-releasing hormone [GnRH] analog plus flutamide) as initial therapy and 11 (31%) were started on monotherapy alone. Patients who had not undergone a previous orchiectomy were continued on the GnRH analog. Patients were monitored clinically and with serial PSA measurements, radionuclide scans, and radiographs as indicated to assess response.

RESULTS

Considering the 35 patients with increasing PSA values, 10 (29%) showed a significant decline (> or = 80% in seven, and > or = 50% in three) in PSA from baseline. All 10 had received combined androgen blockade as initial therapy. The duration of decline was short (median, 5+ months; range, 2 to 10+), but was associated with improvement in clinical symptoms, while one patient had a partial response in an epidural mass with parallel decline in PSA. None of the patients started on single hormone therapies responded.

CONCLUSION

Discontinuation of flutamide was associated with a significant decrease in PSA values in 10 of 25 patients (40%; 95% confidence interval, 21% to 59%) and clinical improvement in a subset of patients who had an initial response, but later progressive disease on combined androgen blockade. A trial of flutamide withdrawal should be considered in patients progressing on total androgen blockade before the initiation of more toxic therapies. It is likely that flutamide withdrawal has contributed to the observed responses in phase II trials of both second-line hormonal therapies and new cytotoxic agents. Future phase II trials in hormone-refractory prostatic cancer must control for this observation, and insure that progression off flutamide is documented before initiation of alternative treatment.

Prostate-specific antigen as a measure of disease outcome in metastatic hormone-refractory prostate cancer

PURPOSE

To evaluate the prognostic significance of pretreatment parameters and posttherapy declines in prostate-specific antigen (PSA) in relation to the survival of patients with hormone-refractory prostate cancer.

PATIENTS AND METHODS

One hundred ten assessable patients treated on seven sequential protocols at Memorial Sloan-Kettering Cancer Center (MSKCC) for hormone-refractory prostate cancer were evaluated for 29 different pretherapy and posttherapy parameters, including a posttherapy decline in PSA of 50% and 80% from baseline.

RESULTS

In the univariate analysis, initial Karnofsky performance status (KPS) > or = 80% was associated with a favorable outcome (P = .005), while age, extent of disease on bone scan, and individual sites of metastatic disease were not significant. No difference in survival was observed between patients with measurable or assessable (bone only) disease. Initial hemoglobin (HGB; P = .0012), alkaline phosphatase (ALK; P = .0015), and lactate dehydrogenase (LDH; P = .0002) levels were significant discriminators, while the initial PSA was not. Using a landmark analysis, a significantly longer median survival rate was observed for patients with a > or = 50% decline in PSA (median not reached) versus patients with a less than 50% decline in PSA (median, 8.6 months; P = .0001). Multivariate analysis using the Cox proportional hazards model showed that a > or = 50% decline in PSA (P = .0004) and the natural log of LDH (P = .0001) were the two most significant variables predicting survival. The model was confirmed on an independent data set from the Norwegian Radium Hospital (NRH) in Oslo, Norway.

CONCLUSION

The results suggest that posttherapy PSA declines can be used as a surrogate end point to evaluate new agents in hormone-refractory prostate cancer. The criteria for response need prospective validation in phase III trials.

Starving the addiction: new opportunities for durable suppression of AR signaling in prostate cancer

Clinical data and models of human disease indicate that androgen receptor (AR) activity is essential for prostate cancer development, growth, and progression. The dependence of prostatic adenocarcinoma on AR signaling at all stages of disease has thereby been exploited in the treatment of disseminated tumors, for which ablation of AR function is the goal of first-line therapy. Although these strategies are initially effective, recurrent tumors arise with restored AR activity, and no durable treatment has yet been identified to combat this stage of disease. New insights into AR regulation and the mechanisms underlying resurgent AR activity have provided fertile ground for the development of novel strategies to more effectively inhibit receptor activity and prolong the transition to therapeutic failure.

Prostate specific antigen decline after antiandrogen withdrawal: the flutamide withdrawal syndrome

Post-therapy changes in prostate specific antigen (PSA) have been proposed as a surrogate end point for response in clinical trials of patients with hormone refractory prostatic cancer. While the specific criteria for response are evolving, there are concerns that changes in serum levels of PSA may be the result of changes in PSA expression or secretion independent of effects on cell growth and proliferation. We report 3 representative cases receiving complete androgen blockade with either gonadotropin-releasing hormone or orchiectomy plus the antiandrogen flutamide, which demonstrated sustained declines in serum PSA levels after discontinuation of the antiandrogen. Similar results have been observed in 6 additional patients. Whether this represents an agonist effect of the antiandrogen is unknown. The results suggest that a trial of flutamide withdrawal is justified in an asymptomatic patient with an increasing PSA before treatment with more toxic therapies. It also shows the importance of documenting sequential elevations in the marker before enrolling a patient in a clinical trial, and that changes in PSA must be interpreted cautiously in clinical trials when an antiandrogen is discontinued.

Changes in fat and lean body mass during androgen-deprivation therapy for prostate cancer

OBJECTIVES

To assess the effects of androgen deprivation therapy on body composition in men with nonmetastatic prostate cancer.

METHODS

In a multicenter study, men with Stage M0 prostate cancer were prospectively evaluated during initial androgen deprivation therapy (gonadotropin-releasing hormone agonist or bilateral orchiectomy). The main outcomes were changes in weight, percentage fat mass, and percentage lean mass from baseline to 12 months.

RESULTS

Seventy-nine subjects were assessed. Serum testosterone concentrations decreased by 79.7% +/- 3.0% (P <0.001). Weight increased by 1.8% +/- 0.5% (P <0.001). The percentage fat mass increased by 11.0% +/- 1.7%, and the percentage lean mass decreased by 3.8% +/- 0.6% (P <0.001 for each comparison).

CONCLUSIONS

Androgen deprivation therapy increased weight and fat mass and decreased lean mass in men with nonmetastatic prostate cancer.

Leuprorelin rescues polyglutamine-dependent phenotypes in a transgenic mouse model of spinal and bulbar muscular atrophy

Spinal and bulbar muscular atrophy (SBMA) is an adult-onset motor neuron disease that affects males. It is caused by the expansion of a polyglutamine (polyQ) tract in androgen receptors. Female carriers are usually asymptomatic. No specific treatment has been established. Our transgenic mouse model carrying a full-length human androgen receptor with expanded polyQ has considerable gender-related motor impairment. This phenotype was abrogated by castration, which prevented nuclear translocation of mutant androgen receptors. We examined the effect of androgen-blockade drugs on our mouse model. Leuprorelin, a lutenizing hormone-releasing hormone (LHRH) agonist that reduces testosterone release from the testis, rescued motor dysfunction and nuclear accumulation of mutant androgen receptors in male transgenic mice. Moreover, leuprorelin treatment reversed the behavioral and histopathological phenotypes that were once caused by transient increases in serum testosterone. Flutamide, an androgen antagonist promoting nuclear translocation of androgen receptors, yielded no therapeutic effect. Leuprorelin thus seems to be a promising candidate for the treatment of SBMA.

Characterization of the intra-prostatic immune cell infiltration in androgen-deprived prostate cancer patients

INTRODUCTION

Our goal was to study the hormonal regulation of immune cell infiltration in prostate cancer patients treated by androgen deprivation therapy (ADT) using an optimized computer-assistance quantification approach.

METHODS

The relative density of immune cell subtypes (CD3(+), CD8(+), CD20(+), CD56(+), CD68(+) and Foxp3(+)) was analyzed by immunohistochemistry in archived prostate specimens from control patients (radical prostatectomy only, n=40) and ADT-treated patients (ADT prior to radical prostatectomy, n=35) using an image analysis software and a whole-slide scanner.

RESULTS

ADT-treated patients had significantly increased relative density of CD3(+) (p<0.001) and CD8(+) T lymphocytes (p<0.001) as well as CD68(+) macrophages (p<0.001). Elevated abundance of CD56(+) Natural Killer (NK) cells was associated with a lower risk of prostate cancer progression (p=0.044), while a high density of CD68(+) macrophages was related to an increased risk of biochemical recurrence (p=0.011).

CONCLUSIONS

Our results demonstrate that the infiltration of specific immune cell subtypes is modulated by ADT. Furthermore our data confirm that NK cells have a protective role against tumor progression while macrophages seem to favor the development of advanced prostate cancer.

Goserelin acetate and flutamide versus bilateral orchiectomy: a phase III EORTC trial (30853). EORTC GU Group and EORTC Data Center

Maximal androgen blockade (MAB), the eradication of the effects of adrenal androgens on prostate cancer cells after castration, has been used with differing success in the treatment of prostatic carcinoma. The aim of this randomized phase III study was to compare the efficacy and side effects of bilateral orchiectomy versus a combination of a luteinizing hormone-releasing hormone agonist (LHRH-A) depot formulation, goserelin acetate (3.6 mg s.c. once every four weeks), and flutamide (250 mg three times daily), in patients with metastatic cancer. Treatment usually continued until disease progression (or for a minimum of three months). Efficacy was assessed by response, time to disease progression, and duration of survival. Clinical evaluations, standard laboratory tests, and imaging examinations were carried out regularly. A total of 327 patients were entered in this study. There was a difference in response only for prostatic acid phosphatase (PAP) with a more frequent decrease of the serum values to normal in the serum in patients assigned to MAB treatment. The MAB treatment, however, proved significantly better for time to subjective progression, time to objective progression, time to first (subjective and objective) progression, and duration of survival. The most frequent side effects for both treatments included hot flushes and gynecomastia. In conclusion, significant time to progression and survival benefits are achieved by adding flutamide to an LHRH-A regimen, probably improving the quality of life of patients with metastatic cancer.

4-Year follow-up results of a European prospective randomized study on neoadjuvant hormonal therapy prior to radical prostatectomy in T2-3N0M0 prostate cancer. European Study Group on Neoadjuvant Treatment of Prostate Cancer

OBJECTIVES

To evaluate the long-term effects of 3-month neoadjuvant hormonal treatment in patients treated by radical prostatectomy for locally confined prostate cancer.

METHODS

We report the results of 402 patients (220 with a clinical T2 tumor and 182 with a clinical T3 tumor) of whom 192 randomly received neoadjuvant total androgen deprivation using a LHRH analogue (goserelin) plus flutamide for a period of 3 months and 210 underwent radical prostatectomy only.

RESULTS

'Clinical downstaging' was seen in 30% of cases in the neoadjuvantly treated group (NEO). 'Pathological downstaging' occurred in 7 and 15% of cases in the direct radical prostatectomy (DP) group and the NEO group, respectively (p<0.01). In patients with clinical T2 as well as in patients with clinical T3 tumors, a significant difference in the number of positive margins was shown in favor of the NEO group (cT2, p<0.01; cT3, p = 0.01). This advantage, although there was a trend in favor of the NEO group, specifically in cT2 tumors, did not translate in a significantly better PSA progression rate (p = 0.18). However, when evaluating the local control rate in cT2 tumors, we observed local recurrence in 3 of 102 (3%) patients in the NEO group versus 12 of 114 (11%) patients in the DP group. The difference is statistically significant (p = 0.03). In the cT3 group, this difference was not statistically significant (NEO group: 15 of 87 (17%), and DP group: 21 of 95 (22%) patients; p = 0.41).

CONCLUSIONS

In this study, the clinical revelance of pathological downstaging and the lower percentage of patients with positive margins in the neoadjuvantly treated group with a clinical T2 tumor is not confirmed by a lower PSA progression rate. However, this study indicates that there may be a trend that this advantage in favor of the NEO group directly translates into a better local control rate in clinical T2 tumors. Better local control in cT2 tumors is only going to be of relevance if subsequently you can show that there is a better survival for these patients. Unfortunately, this article reports a study which is not yet mature enough to show relevant information. Presently, neoadjuvant therapy should not be given outside clinical research settings.

Bicalutamide for advanced prostate cancer: the natural versus treated history of disease

PURPOSE

To determine the therapeutic effects of bicalutamide 200 mg in patients with prostate cancers of different hormone sensitivities.

METHODS

Patients with progressive prostate cancer were treated with bicalutamide 200 mg daily. Before treatment, patients' tumors were classified on the basis of prior hormone exposure and by serum testosterone levels into androgen-dependent and androgen-independent groups. Prior exposure to flutamide and response to flutamide withdrawal was also considered. Outcomes were reported independently on the basis of posttherapy changes in prostate-specific antigen (PSA), measurable disease, and radionuclide bone scans.

RESULTS

Outcomes varied by prior hormone exposure as a higher proportion of patients with progression of androgen-dependent tumors showed posttherapy PSA decreases of more than 50% or more than 80%, measurable disease regression, and improvement on radionuclide bone scans than did patients with androgen-independent progression. Within the category of androgen-independent progression, clinical benefit was observed in patients who had previously progressed on flutamide, independent of the response to flutamide withdrawal. Patients who had progressed on a gonadotropin-releasing hormone (GnRH) analog alone had a low response proportion, whereas those who progressed after two or more hormone therapies did not respond. Overall, the drug was well tolerated. After progression on bicalutamide monotherapy, one third of patients with androgen-dependent progression responded to medical castration with a GnRH analog.

CONCLUSION

Classifying patient tumors on the basis of prior hormone exposure permits a more precise estimate of the potential benefit of a specific hormone therapy for the individual patient. The precision is further increased by reporting the effects of a drug on each parameter of disease independently. The difference in outcomes for patients with androgen-independent progression suggests that the specific hormone therapy administered and the response to that therapy can influence the biology of the relapsing tumor and the sensitivity to subsequent therapies. The sensitivity to bicalutamide after progression on flutamide deserves further study.

High dose bicalutamide for androgen independent prostate cancer: effect of prior hormonal therapy

PURPOSE

A pilot study of the antiandrogen bicalutamide at 150 mg. a day for androgen independent prostate cancer was performed. This study was based on the possibility that androgen independent cases might display responses to additional hormonal agents.

MATERIALS AND METHODS

The study included 31 androgen independent cases with an increasing prostate specific antigen (PSA) and progressive disease. PSA measurements were used as the primary method of assessing response. However, PSA decline was also correlated with clinical status.

RESULTS

Seven patients demonstrated PSA declines of greater than 50% for 2 months or more, for an overall response rate of 22.5%. Responses were observed almost exclusively in patients treated with long-term flutamide as part of a complete androgen blockade regimen (43% response rate) in contrast to patients treated with androgen deprivation without flutamide (6% response rate). Of the 7 PSA responding patients bicalutamide resulted in a significant improvement in performance status and a decrease in analgesic requirement in 4 and 3 remained asymptomatic. Bicalutamide at 150 mg. a day was well tolerated, with the most frequent side effect being mild exacerbation of hot flashes.

CONCLUSIONS

Bicalutamide at this dose is modestly effective for some patients with androgen independent prostate cancer, particularly for those previously treated with long-term flutamide. This study indicates that previous antiandrogen therapy alters the response to subsequent hormonal agents.

Treatment-dependent androgen receptor mutations in prostate cancer exploit multiple mechanisms to evade therapy

Mutations in the androgen receptor (AR) that enable activation by antiandrogens occur in hormone-refractory prostate cancer, suggesting that mutant ARs are selected by treatment. To validate this hypothesis, we compared AR variants in metastases obtained by rapid autopsy of patients treated with flutamide or bicalutamide, or by excision of lymph node metastases from hormone-naïve patients. AR mutations occurred at low levels in all specimens, reflecting genetic heterogeneity of prostate cancer. Base changes recurring in multiple samples or multiple times per sample were considered putative selected mutations. Of 26 recurring missense mutations, most in the NH(2)-terminal domain (NTD) occurred in multiple tumors, whereas those in the ligand binding domain (LBD) were case specific. Hormone-naïve tumors had few recurring mutations and none in the LBD. Several AR variants were assessed for mechanisms that might underlie treatment resistance. Selection was evident for the promiscuous receptor AR-V716M, which dominated three metastases from one flutamide-treated patient. For the inactive cytoplasmically restricted splice variant AR23, coexpression with AR enhanced ligand response, supporting a decoy function. A novel NTD mutation, W435L, in a motif involved in intramolecular interaction influenced promoter-selective, cell-dependent transactivation. AR-E255K, mutated in a domain that interacts with an E3 ubiquitin ligase, led to increased protein stability and nuclear localization in the absence of ligand. Thus, treatment with antiandrogens selects for gain-of-function AR mutations with altered stability, promoter preference, or ligand specificity. These processes reveal multiple targets for effective therapies regardless of AR mutation.

Treatment with flutamide, metformin, and their combination added to a hypocaloric diet in overweight-obese women with polycystic ovary syndrome: a randomized, 12-month, placebo-controlled study

CONTEXT

The few controlled trials performed so far indicate that the addition of metformin and/or flutamide to a hypocaloric diet in obese women with polycystic ovary syndrome (PCOS) effectively influences different phenotypic aspects of the syndrome. All these studies are, however, characterized by a short to medium period of treatment.

OBJECTIVE

Our objective was to investigate the long-term effects of these therapies.

DESIGN AND SETTING

We conducted a prospective, randomized, placebo-controlled trial at a medical center.

PATIENTS

Of 80 overweight-obese women with PCOS, 76 completed the study.

INTERVENTIONS

Patients were placed on a hypocaloric diet for the first month and then on a hypocaloric diet plus placebo, metformin (850 mg, orally, twice a day), flutamide (250 mg, orally, twice a day), or metformin plus flutamide for the subsequent 12 months (20 subjects in each group).

MAIN OUTCOME MEASURES

We assessed clinical features, computerized tomography measurement of fat distribution, androgens, lipids, and fasting and glucose-stimulated glucose and insulin levels at baseline and after 6 and 12 months of treatment.

RESULTS

After 6 months, compared with placebo, flutamide further decreased visceral/sc fat mass (P = 0.044), androstenedione (P < 0.001), dehydroepiandrosterone sulfate (P < 0.001), and hirsutism score (P < 0.001), whereas metformin further increased frequency of menstruation (P = 0.039). After 12 months, flutamide maintained the effects observed after 6 months on visceral/sc fat mass (P = 0.033) and androstenedione (P < 0.001), whereas it produced an additional decrease in dehydroepiandrosterone sulfate (P = 0.020) and hirsutism score (P = 0.019); metformin further improved the menstrual pattern (P = 0.013). Moreover, after 12 months, flutamide improved more than placebo the menstrual pattern (P = 0.008), glucose-stimulated glucose levels (P = 0.041), insulin sensitivity (P < 0.001), and low-density lipoprotein cholesterol levels (P = 0.003), whereas metformin decreased glucose-stimulated insulin levels (P = 0.014). The combination of the two drugs maintained the specific effect of each of the compounds, without any additive or synergistic effect.

CONCLUSIONS

These findings add relevance to the usefulness of metformin and flutamide in the treatment of dieting overweight-obese PCOS women and provide a rationale for targeting different therapeutic options according to the required outcomes in the long term.

Effect of flutamide and metformin administered alone or in combination in dieting obese women with polycystic ovary syndrome

BACKGROUND

Hyperandrogenism, hyperinsulinaemia and obesity play a key and coordinating roles in the pathogenesis of polycystic ovary syndrome (PCOS), contributing in different ways to the clinical expression of the syndrome. Weight loss is beneficial, but the additional administration of insulin-lowering drugs, such as metformin, and antiandrogens may produce further benefits, due to their different spectrum of action. The effects of long-term metformin and flutamide, an antiandrogen drug, added alone or in combination with a low-calorie diet, on body weight and fat distribution, androgens, metabolic parameters and clinical status in obese women with PCOS were investigated.

METHODS

Forty obese women with PCOS were enrolled in the study. After a 1-month diet, according to single-blind design, the patients were allocated to treatment with placebo, metformin (850 mg/orally, twice daily), flutamide (250 mg/orally, twice daily) or metformin (850 mg/orally, twice daily) + flutamide (250 mg/orally, twice daily) for the following 6 months, while continuing hypocaloric dieting. At baseline and at the end of the study, sex hormone, SHBG, lipid, insulin and insulin sensitivity determinations were evaluated. At the same time, clinical parameters such as anthropometry, total (TAT), visceral (VAT) and subcutaneous (SAT) adipose tissue, hirsutism and menses were also measured.

RESULTS

We found that, in obese PCOS women, following a hypocaloric diet the addition of metformin, flutamide or the combined metformin + flutamide treatment had some specific additional favourable effects with respect to the low-calorie diet alone. In particular, flutamide treatment seemed to add a significant effect in decreasing visceral fat, androstenedione, DHEA-S, total and low density lipoprotein (LDL) cholesterol and in improving hirsutism. Conversely, metformin had significant benefits on the menstrual status. The two drugs showed an additive effect in reducing testosterone concentrations and a synergistic effect in increasing high density lipoprotein (HDL) cholesterol and SHBG levels. Improvement of insulin sensitivity and hyperinsulinaemia appeared to depend on hypocaloric diet, without any further significant effect of the pharmacological treatments, either alone or in combination.

CONCLUSIONS

We conclude that, in obese PCOS women, following a hypocaloric diet the addition of metformin, flutamide or the combined metformin + flutamide treatment appears to have a more favourable outcome on body fat distribution, androgens, lipids, hirsutism and menses. However, our data emphasize the dominant role of hypocaloric dieting in improving insulin resistance and hyperinsulinaemia. Therefore, this study provides a rationale for specifically targeting different therapeutical options for PCOS according to the required outcomes.