Goserelin acetate with or without antiandrogen or estrogen in the treatment of patients with advanced prostate cancer: a multicenter, randomized, controlled trial in Japan. Zoladex Study Group

Absence of PSA Flare With Apalutamide Administered 1 Hour in Advance With GnRH Agonists: Case Report

Objective

To examine the effects of apalutamide on endocrine function and flare prevention in metastatic hormone-sensitive prostate cancer (mHSPC) patients administered GnRH agonists.

Methods

The first newly diagnosed mHSPC patient took apalutamide for 2 weeks followed by combination with GnRH agonist, as recommended by clinical guidelines. Serum luteinizing hormone (LH), testosterone, and PSA were detected during the oral administration of apalutamide before and after ADT. Eight newly diagnosed mHSPC patients innovatively took apalutamide 1 hour before GnRH agonist administration; LH, testosterone and PSA were detected before and after ADT.

Results

In the first patient, LH and testosterone levels were increased during apalutamide monotherapy, and serum PSA levels decreased rapidly, demonstrating apalutamide effectively blocked AR signaling. In patients on the 1-hour regimen, combined treatment with apalutamide and GnRH agonists led to peak level of testosterone on day 3 and castration level on day 28, while PSA decreased continuously. No one experienced dysuria or bone pain worsen after ADT.

Conclusion

Taking apalutamide 1 hour in advance may effectively prevent the flare-up effect in prostate cancer patients treated with GnRH agonists. Compared with the 2-week regimen, the 1-hour regimen could simplify the treatment process and bring testosterone to castration levels in advance.

Chirality and the Origin of Life

The origin of life, based on the homochirality of biomolecules, is a persistent mystery. Did life begin by using both forms of chirality, and then one of the forms disappeared? Or did the choice of homochirality precede the formation of biomolecules that could ensure replication and information transfer? Is the natural choice of L-amino acids and D-sugars on which life is based deterministic or random? Is the handedness present in/of the Universe from its beginning? The whole biosystem on the Earth, all living creatures are chiral. Many theories try to explain the origin of life and chirality on the Earth: e.g., the panspermia hypothesis, the primordial soup hypothesis, theory of parity violation in weak interactions. Additionally, heavy neutrinos and the impact of the fact that only left-handed particles decay, and even dark matter, all have to be considered.

Quo Vadis Advanced Prostate Cancer Therapy? Novel Treatment Perspectives and Possible Future Directions

Prostate cancer is a very common disease, which is, unfortunately, often the cause of many male deaths. This is underlined by the fact that the early stages of prostate cancer are often asymptomatic. Therefore, the disease is usually detected and diagnosed at late advanced or even metastasized stages, which are already difficult to treat. Hence, it is important to pursue research and development not only in terms of novel diagnostic methods but also of therapeutic ones, as well as to increase the effectiveness of the treatment by combinational medicinal approach. Therefore, in this review article, we focus on recent approaches and novel potential tools for the treatment of advanced prostate cancer; these include not only androgen deprivation therapy, antiandrogen therapy, photodynamic therapy, photothermal therapy, immunotherapy, multimodal therapy, but also poly(ADP-ribose) polymerase, Akt and cyclin-dependent kinase inhibitors.

Efficacy and safety of combined androgen blockade with antiandrogen for advanced prostate cancer

Background

Combined androgen blockade (cab) is a promising treatment modality for prostate cancer (pca). In the present meta-analysis, we compared the efficacy and safety of first-line cab using an antiandrogen (aa) with castration monotherapy in patients with advanced pca.

Methods

PubMed, embase, Cochrane, and Google Scholar were searched for randomized controlled trials (rcts) published through 12 December 2016. Hazard ratios (hrs) with 95% confidence intervals (cis) were determined for primary outcomes: overall survival (os) and progression-free survival (pfs). Subgroup analyses were performed for Western compared with Eastern patients and use of a nonsteroidal aa (nsaa) compared with a steroidal aa (saa).

Results

Compared with castration monotherapy, cab using an aa was associated with significantly improved os (n = 14; hr: 0.90; 95% ci: 0.84 to 0.97; p = 0.003) and pfs (n = 13; hr: 0.89; 95% ci: 0.80 to 1.00; p = 0.04). No significant difference in os (p = 0.71) and pfs (p = 0.49) was observed between the Western and Eastern patients. Compared with castration monotherapy, cab using a nsaa was associated with significantly improved os (hr: 0.88; 95% ci: 0.82 to 0.95; p = 0.0009) and pfs (hr: 0.85; 95% ci: 0.73 to 0.98; p = 0.007)-a result that was not achieved with cab using a saa. The safety profiles of cab and monotherapy were similar in terms of adverse events, including hot flushes, impotence, and grade 3 or 4 events, with the exception of risk of diarrhea and liver dysfunction or elevation in liver enzymes, which were statistically greater with cab using an aa.

Conclusions

Compared with castration monotherapy, first-line cab therapy with an aa, especially a nsaa, resulted in significantly improved os and pfs, and had an acceptable safety profile in patients with advanced pca.

Effect of adjuvant hormone therapy in patients with prostate cancer: A meta-analysis of randomized controlled trials

OBJECTIVES

To summarize the evidence regarding the treatment effect of adjuvant hormone therapy (AHT) in patients with prostate cancer (PCa). AHT following radiotherapy, chemotherapy, or surgery is widely used in patients with PCa. However, the treatment effect is inconsistent in individual trials.

METHODS

The electronic databases including PubMed, EmBase, and Cochrane Library were searched to identify randomized controlled trials (RCTs) in September 2016. RCTs that evaluated the effects of AHT in patients with PCa were included. Hazard ratio (HR) and relative risks (RR) were used to measure the treatment effects of AHT using a random effects model. The analyses were further stratified by factors that could affect the treatment efficacy.

RESULTS

A total of 14,594 potential studies were identified, and 27 RCTs were included. Compared with the control group, patients who received AHT were associated with a significant improvement in overall survival (OS) (HR: 0.78; 95% confidence interval [CI]: 0.71-0.85; P <.001), disease-free survival (DFS) (HR: 0.50; 95% CI: 0.39-0.65; P <.001), total mortality (RR: 0.90; 95% CI: 0.85-0.96; P = .001), recurrence (RR: 0.70; 95% CI: 0.60-0.81; P <.001), and disease-specific mortality (RR: 0.70; 95% CI: 0.56-0.87; P <.001). However, no significant difference was observed between AHT and control for response rate (RR: 1.75; 95% CI: 0.91-3.37; P = .095).

CONCLUSIONS

The findings of this meta-analysis confirmed that patients who received AHT had a significant improvement in OS, DFS, total mortality, recurrence, and disease-specific mortality. Further, large-scale RCTs are required to evaluate the treatment effect in specific subpopulations.

Patterns of Bicalutamide Use in Prostate Cancer Treatment: A U.S. Real-World Analysis Using the SEER-Medicare Database

INTRODUCTION

Bicalutamide (BIC), a non-steroidal anti-androgen, is FDA-indicated for use in combination with a luteinizing hormone-releasing hormone (LHRH) analog for treatment of Stage D2 metastatic carcinoma of the prostate. Lack of consensus exists regarding the clinical benefit of BIC use, either alone or combined use of BIC with an LHRH analog or antagonist (combined androgen blockade or CAB), versus treatment with androgen deprivation therapy (ADT) alone.

METHODS

The SEER-Medicare database was used to identify prostate cancer patients aged ≥ 66 years diagnosed between 2007 and 2011 and who filled at least one prescription for BIC. Duration of BIC treatment was assessed in relation to ADT use; either alone (monotherapy), as part of CAB only, and as part of CAB followed by monotherapy. Additionally, we assessed use of BIC during or outside a potential testosterone flare prevention period (initiation within 2 months of an LHRH agonist).

RESULTS

A total of 7521 prostate cancer patients who filled a prescription for BIC were identified. Eighteen percent of the cohort used BIC alone, over half the patients (54%) used BIC as part of CAB and 27% used BIC as part of CAB followed by monotherapy. Among men treated with BIC as part of CAB, 58% received BIC only within the potential flare period.

CONCLUSIONS

Although there is no FDA indication for BIC use as monotherapy, > 44% of patients in this study used BIC alone or as part of CAB followed by monotherapy. Further research is necessary to understand the outcomes of BIC utilization in these settings, particularly compared with newer second-generation anti-androgens.

FUNDING

Medivation LLC, a Pfizer company, and Astellas, Pharma, Inc.

G protein-coupled receptors: the evolution of structural insight

G protein-coupled receptors (GPCR) comprise a diverse superfamily of over 800 proteins that have gained relevance as biological targets for pharmaceutical drug design. Although these receptors have been investigated for decades, three-dimensional structures of GPCR have only recently become available. In this review, we focus on the technological advancements that have facilitated efforts to gain insights into GPCR structure. Progress in these efforts began with the initial crystal structure determination of rhodopsin (PDB: 1F88) in 2000 and has continued to the most recently published structure of the A_1AR (PDB: 5UEN) in 2017. Numerous experimental developments over the past two decades have opened the door for widespread GPCR structural characterization. These efforts have resulted in the determination of three-dimensional structures for over 40 individual GPCR family members. Herein we present a comprehensive list and comparative analysis of over 180 individual GPCR structures. This includes a summary of different GPCR functional states crystallized with agonists, dual agonists, partial agonists, inverse agonists, antagonists, and allosteric modulators.

Risk of Testosterone Flare in the Era of the Saturation Model: One More Historical Myth

CONTEXT

When luteinizing hormone-releasing hormone (LHRH) agonists were introduced in the 1980s, it was universally believed that the initial transient rise in serum testosterone (T), termed T flare, caused rapid prostate cancer (PCa) growth and led to disease progression, complications, and death. It became routine to offer antiandrogens (AAs) to prevent these risks. However, over the last decade, it has become recognized that androgens have a finite ability to stimulate PCa growth (the saturation model), providing a theoretical challenge to the risks of T flare.

OBJECTIVE

To review evidence for the risks associated with T flare from a modern perspective, specifically prostate-specific antigen (PSA) flare, disease progression, and spinal cord compression.

EVIDENCE ACQUISITION

An Ovid Medline database search was conducted to identify articles related to "testosterone flare", "disease flare", and "PSA flare" associated with LHRH agonists. The literature review included papers published from May 1, 1980 through May 1, 2016. Key search terms included, luteinizing hormone-releasing hormone, gonadotropin-releasing hormone, and antiandrogens.

EVIDENCE SYNTHESIS

Initial administration of LHRH agonists uniformly results in peak increases in serum T by 40-100% on days 2-3, returning to baseline by days 7-8, after which T declines to castrate levels by approximately 2-3 wk. Of six LHRH agonist studies reporting PSA during the period of T flare, five showed no significant rise in PSA despite the presence of advanced disease with mean baseline PSA as high as ≥500ng/ml. Evidence for disease flare was limited to one report of greater bone pain with LHRH agonists alone versus LHRH agonists with AAs. Three other RCTs reported no disease flare. Rates of spinal cord compression were no greater for LHRH agonists alone compared with castration or estrogen treatment. We identified no studies of men treated with LHRH agonists versus placebo/no treatment to assess the effects of LHRH agonists compared with the natural history of advanced PCa.

CONCLUSIONS

Although T flare has been considered risky for 30 yr, a modern review of the evidence collected primarily in the 1980s and 1990s fails to support this view. Specifically, T flare does not appear to be associated with significantly increased PSA, disease progression, or adverse events, even in men with widely metastatic disease. These results are consistent with the saturation model, first introduced in 2006. There seems little value in adding AA to LHRH agonists, except possibly for men with extensive vertebral metastases and serum T concentrations well below the saturation point of approximately 250ng/dl (8.7nmol/l).

PATIENT SUMMARY

A review of the literature reveals no evidence for increased risks associated with testosterone flare from the initiation of luteinizing hormone-releasing hormone (LHRH) agonists. This appears to be an unsupported belief from an earlier era when our understanding of testosterone's relationship to prostate cancer was less sophisticated. Except in rare instances, there appears to be no need to use an androgen blocker when beginning treatment with LHRH agonists.

A phase III multicenter, randomized, controlled study of combined androgen blockade with versus without zoledronic acid in prostate cancer patients with metastatic bone disease: results of the ZAPCA trial

OBJECTIVE

To examine the antitumor activity of zoledronic acid (ZA) combined with androgen deprivation therapy (ADT) for men with treatment-naive prostate cancer and bone metastasis.

METHODS

We enrolled 227 men with treatment-naive prostate cancer and bone metastasis. Participants were randomly assigned (1:1 ratio) to receive combined androgen blockade alone (CAB group) or ZA with combined androgen blockade (CZ group). Time to treatment failure (TTTF), time to the first skeletal-related event (TTfSRE), and overall survival (OS) rates were estimated using the Kaplan-Meier method. Hazard ratios (HRs) were calculated using the Cox proportional hazards model. Median follow-up duration was 41.5 months.

RESULTS

Median TTTFs were 12.4 and 9.7 months for the CZ and CAB groups, respectively (HR 0.75; 95 % CI 0.57-1.00; p = 0.051). For men with baseline prostate-specific antigen levels <200 ng/mL, median TTTFs were 23.7 and 9.8 months for the CZ and CAB groups, respectively (HR 0.58; 95 % CI 0.35-0.93; p = 0.023). Median TTfSREs were 64.7 and 45.9 months for the CZ and CAB groups, respectively (HR 0.58; 95 % CI 0.38-0.88; p = 0.009). OS was similar between the groups.

CONCLUSIONS

This study failed to demonstrate that combined use of ZA and ADT significantly prolonged TTTF in men with treatment-naive prostate cancer and bone metastasis. However, it generates a new hypothesis that the combined therapy could delay the development of castration resistance in a subgroup of patients with low baseline prostate-specific antigen values <200 ng/mL. The treatment also significantly prolonged TTfSRE but did not affect OS.

Degarelix monotherapy compared with luteinizing hormone-releasing hormone (LHRH) agonists plus anti-androgen flare protection in advanced prostate cancer: an analysis of two randomized controlled trials

OBJECTIVES

The objective of this study was to assess differences in efficacy outcomes between luteinizing hormone-releasing hormone (LHRH) agonist plus antiandrogen (AA) flare protection and monotherapy with the gonadotrophin-releasing hormone antagonist degarelix in patients with prostate cancer.

METHODS

Data from 1455 patients were pooled from two prospective, phase III randomized 1-year clinical trials of degarelix versus LHRH agonist with or without AA. The AA bicalutamide was administered at the investigator's discretion. Adjusted hazard ratios (HRs) were calculated using a Cox proportional hazards regression model and a conditional logistic regression model was used for a case-control analysis of odds ratios (ORs).

RESULTS

Patients received degarelix monotherapy (n = 972) or LHRH agonist (n = 483) of whom 57 also received AA. Overall, prostate-specific antigen progression-free survival (PSA PFS) was improved with degarelix versus LHRH agonist + AA (Cox proportional hazards regression model-adjusted HR for PSA PFS failure was 0.56 [95% confidence interval (CI) 0.33-0.97, p = 0.038]). To compensate for a higher proportion of patients with metastases, Gleason score 7-10, and PSA >20 ng/ml in the LHRH agonist + AA group, a case-control analysis using a conditional logistic regression model was utilized. This resulted in an OR for PSA PFS of 0.42 (95% CI 0.20-0.89; p = 0.023) in the overall population, and 0.35 (95% CI 0.13-0.96; p = 0.042) in patients with PSA >50 ng/ml at baseline, when treated with degarelix versus LHRH agonists + AA. There were a small number of deaths, 1.9% with degarelix and 7% with LHRH agonists + AA (case-control analysis OR = 0.37; p = 0.085).

CONCLUSIONS

Degarelix monotherapy produced a more favorable effect on PSA PFS outcomes than a LHRH agonist + AA flare protection therapy in patients with prostate cancer when a case-control analysis was used to compensate for differences between treatment groups.

Recent discoveries and developments of androgen receptor based therapy for prostate cancer

The main focus of this review is to discuss the discoveries and developments of various therapies for prostate cancer.

Adverse reactions to targeted and non-targeted chemotherapeutic drugs with emphasis on hypersensitivity responses and the invasive metastatic switch

More than 100 drugs are used to treat the many different cancers. They can be divided into agents with relatively broad, non-targeted specificity and targeted drugs developed on the basis of a more refined understanding of individual cancers and directed at specific molecular targets on different cancer cells. Individual drugs in both groups have been classified on the basis of their mechanism of action in killing cancer cells. The targeted drugs include proteasome inhibitors, toxic chimeric proteins and signal transduction inhibitors such as tyrosine kinase (non-receptor and receptor), serine/threonine kinase, histone deacetylase and mammalian target of rapamycin inhibitors. Increasingly used targeted vascular (VEGF) and platelet-derived endothelial growth factor blockade can provoke a range of pathological consequences. Many of the non-targeted drugs are cytotoxic, suppressing haematopoiesis as well as provoking cutaneous eruptions and vascular, lung and liver injury. Cytotoxic side effects of the targeted drugs occur less often and usually with less severity, but they show their own unusual adverse effects including, for example, a lengthened QT interval, a characteristic papulopustular rash, nail disorders and a hand-foot skin reaction variant. The term hypersensitivity is widely used across a number of disciplines but not always with the same definition in mind, and the terminology needs to be standardised. This is particularly apparent in cancer chemotherapy where anti-neoplastic drug-induced thrombocytopenia, neutropenia, anaemia, vascular disorders, liver injury and lung disease as well as many dermatological manifestations sometimes have an immune basis. The most insidious of all adverse consequences of targeted therapies, however, are tumour adaptation, increased malignancy and the invasive metastatic switch seen with anti-angiogenic drugs that inhibit the VEGF-A pathway. Adverse reactions to 44 non-targeted and 33 targeted, frequently used, chemotherapeutic drugs are presented together with discussions of diagnosis, premedications, desensitizations and importance of understanding the mechanisms underlying the various drug-induced reactions. There is need for wide-ranging acceptance of what constitutes a hypersensitivity reaction and for allergists to be more involved in the diagnosis, treatment and prevention of chemotherapeutic drug-induced hypersensitivity reactions.

External beam radiotherapy for clinically localized hormone-refractory prostate cancer: clinical significance of Nadir prostate-specific antigen value within 12 months

PURPOSE

To analyze retrospectively the results of external beam radiotherapy for clinically localized hormone-refractory prostate cancer and investigate the clinical significance of nadir prostate-specific antigen (PSA) value within 12 months (nPSA12) as an early estimate of clinical outcomes after radiotherapy.

METHODS AND MATERIALS

Eighty-four patients with localized hormone-refractory prostate cancer treated with external beam radiotherapy were retrospectively reviewed. The total radiation doses ranged from 30 to 76 Gy (median, 66 Gy), and the median follow-up period for all 84 patients was 26.9 months (range, 2.7-77.3 months).

RESULTS

The 3-year actuarial overall survival, progression-free survival (PFS), and local control rates in all 84 patients after radiotherapy were 67%, 61%, and 93%, respectively. Although distant metastases and/or regional lymph node metastases developed in 34 patients (40%) after radiotherapy, local progression was observed in only 5 patients (6%). Of all 84 patients, the median nPSA12 in patients with clinical failure and in patients without clinical failure was 3.1 ng/mL and 0.5 ng/mL, respectively. When dividing patients according to low (<0.5 ng/mL) and high (>or=0.5 ng/mL) nPSA12 levels, the 3-year PFS rate in patients with low nPSA12 and in those with high nPSA12 was 96% and 44%, respectively (p < 0.0001). In univariate analysis, nPSA12 and pretreatment PSA value had a significant impact on PFS, and in multivariate analysis nPSA12 alone was an independent prognostic factor for PFS after radiotherapy.

CONCLUSIONS

External beam radiotherapy had an excellent local control rate for clinically localized hormone-refractory prostate cancer, and nPSA12 was predictive of clinical outcomes after radiotherapy.

Luteinizing Hormone-Releasing Hormone I (LHRH-I) and Its Metabolite in Peripheral Tissues

Luteinizing hormone-releasing hormone (LHRH) was first isolated in the mammalian hypothalamus and shown to be the primary regulator of the reproductive system through its initiation of pituitary gonadotropin release. Since its discovery, this form of LHRH (LHRH-I) has been shown to be one of many structural variants with a variety of roles in both the brain and peripheral tissues. Enormous interest has been focused on LHRH-I and LHRH-II and their cognate receptors as targets for designing therapies to treat cancers of the reproductive system. LHRH-I is processed by a zinc metalloendopeptidase EC 3.4.24.15 (EP24.15) that cleaves the hormone at the fifth and sixth bond of the decapeptide (Tyr5-Gly6) to form LHRH-( 1 – 5 ). We have previously reported that the autoregulation of LHRH gene expression can also be mediated by its processed peptide, LHRH-( 1 – 5 ). Furthermore, LHRH-( 1 – 5 ) has also been shown to be involved in cell proliferation. This review will focus on the possible roles of LHRH and its processed peptide, LHRH-( 1 – 5 ), in non-hypothalamic tissues.

Effects of flutamide as a second-line agent for maximum androgen blockade of hormone refractory prostate cancer

We analyzed clinical effects of flutamide as a second-line agent for maximum androgen blockade (MAB) in patients with relapsing prostate cancer who received bicalutamide as the first-line MAB agent. This study included 13 patients with progressive prostate cancer who had relapsed after first-line MAB, with bicalutamide at 80 mg/day. After checking for antiandrogen withdrawal syndrome, they were given flutamide at 375 mg/day as second-line MAB. The effectiveness of that therapy was evaluated by changes in prostatic specific antigen (PSA) levels, with response defined as a decrease of greater than 50% from the start of therapy. We also compared several factors between responders and non-responders. Nine (69.2%) of the 13 patients showed a decrease in PSA levels, of whom five (38.5%) had a greater than 50% decrease and were defined as responders. The median duration of PSA response was 11.0 months (range 5-20 months). Patients who had a longer duration of response to first-line MAB had a significantly greater response to second-line MAB. For advanced prostate cancer patients who progressed on first-line MAB with bicalutamide, flutamide administration as a second-line antiandrogen was found to be relatively effective, especially for those who showed a longer duration of response to the first-line MAB. Our results confirm previous findings that MAB using flutamide is an effective second-line hormonal therapy.

Bicalutamide 80 mg combined with a luteinizing hormone-releasing hormone agonist (LHRH-A) versus LHRH-A monotherapy in advanced prostate cancer: findings from a phase III randomized, double-blind, multicenter trial in Japanese patients

To compare combination therapy with bicalutamide 80 mg and a luteinizing hormone-releasing hormone agonist (LHRH-A) versus LHRH-A alone in Japanese men with untreated advanced prostate cancer. A total of 205 patients with stage C/D prostate cancer were randomized to either LHRH-A+once-daily oral bicalutamide 80 mg or placebo. Primary study variables have been reported previously. Secondary variables included: time to achieve prostate-specific antigen < or = 4 ng/ml, time-to-treatment failure (TTTF), time-to-disease progression (TTP), overall survival (OS), adverse events and adverse drug reactions. Following combination therapy with bicalutamide 80 mg, there were significant (P<0.001) advantages over LHRH-A alone in terms of TTTF and TTP, but the difference in the interim OS was not statistically significant. First-line combination therapy with bicalutamide 80 mg in Japanese patients with advanced prostate cancer offers significant benefits over LHRH-A alone, with respect to TTTF and TTP. Follow-up for OS continues.

INCIDENCE AND MANAGEMENT OF GYNECOMASTIA IN MEN TREATED FOR PROSTATE CANCER

PURPOSE

Gynecomastia is a potentially treatment limiting adverse event in men receiving hormone therapy for prostate cancer.

MATERIALS AND METHODS

In large, randomized, placebo controlled studies approximately 50% or more of patients with prostate cancer experienced gynecomastia due to multiple mechanisms. Although its severity was mostly reported as mild to moderate, gynecomastia was cited as the reason for most premature withdrawals from therapy. In patients with advanced forms of prostate cancer bilateral orchiectomy was associated with the lowest incidence of gynecomastia, followed by nonsteroidal antiandrogen therapy, diethylstilbestrol and estrogen in rank order.

RESULTS

It is important that gynecomastia is well managed in patients with prostate cancer who want to proceed with hormone therapy. Patients should be assessed for the likely etiology of gynecomastia and preventive therapy or treatment for established gynecomastia should be instituted. Prophylactic radiotherapy has been shown to decrease the incidence of hormone induced gynecomastia by more than 50%. An alternative course of action, which may be more convenient for the patient, is the prophylactic use of tamoxifen. Tamoxifen may also mitigate or resolve gynecomastia during its early or proliferative phase. In severe long-standing gynecomastia surgery is warranted since medical therapies are less likely to succeed. Aromatase inhibitors and 4-hydroxytamoxifen are investigational.

CONCLUSIONS

Gynecomastia is a significant problem in men undergoing hormonal therapy for prostate cancer. It requires prompt recognition, evaluation and management.

External beam radiotherapy for clinically node-negative, localized hormone-refractory prostate cancer: impact of pretreatment PSA value on radiotherapeutic outcomes

PURPOSE

To analyze the results of clinically node-negative, localized hormone-refractory prostate cancer treated with external beam radiotherapy (EBRT) and to investigate the potential prognostic factors that influenced the therapeutic outcome.

METHODS AND MATERIALS

Fifty-three patients who had developed localized hormone-refractory prostate cancer were treated with EBRT between 1994 and 2001. According to the 1992 American Joint Committee on Cancer clinical stage, 4 patients had T2 and 49 had T3 at the start of RT, and 14 patients had a Gleason score <7, 14 had a Gleason score of 7, and 23 had a Gleason score of 8-10. All patients were treated with EBRT using the unblocked oblique four-field technique, with a total dose of 69 Gy. The fraction dose was 3 Gy three times weekly. The median follow-up after RT was 35 months (range, 8-96 months) and after androgen ablation was 73 months (range, 42-156 months).

RESULTS

Of 53 patients, 15 patients subsequently developed clinical relapse, including locoregional and/or distant metastases. The site of first relapse was bone metastasis in 10, lymph nodes in 3, and local failure in 2 patients; 3 patients died of prostate cancer during the analysis period. The 3-year and 5-year cause-specific survival rate was 94% and 87%, respectively, and the 3-year and 5-year clinical relapse-free survival rate was 78% and 56%, respectively. The univariate analysis revealed that a short prostate-specific antigen (PSA) doubling time and high PSA value at the start of RT and a high Gleason score were statistically significant factors for the risk of clinical relapse. Multivariate analysis demonstrated that the PSA value (PSA <or=15 vs. >or=15 ng/mL) at the start of RT was an independent prognostic factor.

CONCLUSION

EBRT could be a treatment of choice for clinically node-negative, localized, hormone-refractory prostate cancer.

A prospective and randomized study of primary hormonal therapy for patients with localized or locally advanced prostate cancer unsuitable for radical prostatectomy: results of the 5-year follow-up

OBJECTIVE

To evaluate the effect of primary hormonal therapy for patients with localized and locally advanced prostate cancer.

PATIENTS AND METHODS

Patients with stage T1b-T3 prostate cancer who were not scheduled for radical prostatectomy were allocated into two groups: group 1 (73 men) received luteinizing hormone-releasing hormone (LHRH) agonist monotherapy and group 2 (78 men) received LHRH agonist and chlormadinone acetate. Patients were followed using serum prostate specific antigen levels, prostate size and the detection of distant metastasis for 5 years.

RESULTS

The median (range) follow-up was 78 (63-87) months. The 5-year progression-free survival rate was significantly higher in group 2 (68%) than in group 1 (47%). However, the overall and cause-specific survival rate at 5 years were similar in both groups, at 72% and 93% in group 1, and 64% and 89% in group 2, respectively.

CONCLUSION

The overall survival rates of the both groups were no different from that of the normal Japanese population of the same age group. Although this study did not include an untreated group, i.e. watchful waiting, these results might indicate the usefulness of primary hormonal therapy in controlling localized and locally advanced prostate cancer. The 5-year observation period is still short and the study is continuing to determine the 10-year survival.