Survival of patients with hormone refractory prostate cancer in the prostate specific antigen era

Overall survival and second primary malignancies in men with metastatic prostate cancer

Background

Among prostate cancer (PC) patients, over 90% of distant metastases occur in the bone. PC treatments may be associated with side effects, including second primary malignancies (SPM). There is limited information on the incidence of SPM among men with bone metastatic PC (mPC) and among men with bone metastatic castration-resistant PC (mCRPC). We estimated overall survival and the incidence of SPM in men with mPC and mCRPC.

Methods

In the Prostate Cancer data Base Sweden, the National Prostate Cancer Register was linked to other national health care registers, 15,953 men with mPC in 1999–2011 were identified. Further, 693 men with mCRPC were identified. Outcomes were evaluated using stratified incidence rates, Kaplan-Meier estimators and Cox models.

Results

The mean age among men with mPC was 73.9 years and in men with mCRPC 70.0 years. The median respective survivals were 1.5 (13,965 deaths) and 1.14 years (599 deaths), and average times since PC diagnosis 1.8 and 4.7 years. We observed 2,669 SPMs in men with mPC and 100 SPMs in men with mCRPC. The incidence rate of SPM per 1,000 person-years was 81.8 (78.8–85.0) for mPC and 115.6 (95.1–140.7) for mCRPC. High age, prior neoplasms, urinary tract infection, congestive heart failure, diabetes and renal disease were most strongly associated with increased mortality risk. Prior neoplasms and prior use of antineoplastic agents were most strongly associated with increased SPM risk. Several factors associated with increased mortality and SPM risks were more prevalent in the mCRPC cohort.

Conclusions

Our results on mortality for men with mPC and mCRPC are in line with previous studies from the same time period. Investigation of factors associated with mortality and SPM in men with mPC and mCRPC can help to further understand these outcomes in the era prior to several new treatments have come available.

A Study of the Anti-Cancer Effects of the Hexane Fraction of the Methanol Extract of Forsythiae Fructus

Background:

Forsythiae Fructus (FF) is a well-known medicinal herb derived from the dried fruits of Forsythia suspensa (Thunb.) Vahl. (Oleaceae). Recently, bioactive compounds isolated from hydrophobic solvent fractions of FF have been reported to have anti-oxidant, antibacterial, and anti-cancer effects.

Objective:

Almost all herbal medicines are derived from water extracts, which suggests different extraction methods might enhance the practical efficacies of herbal medicines. In this study, the authors further investigated the most potential anti-cancer fraction, that is, the hexane fraction (FFH) of the methanol extract (FFM) of the dried fruits of Forsythia suspensa.

Materials and Methods:

FFH was investigated by measuring its effects on the viability and apoptotic death of PC-3 cells (a prostate cancer cell line), on the expression levels of Bcl-2, Bax, cytochrome c, procaspase-9, procaspase-3 and PARP, and caspase-3 activity.

Results:

FFH significantly accelerated apoptotic cell death and decreased the protein levels of Bcl-2, procaspase-9, and procaspase-3.

Conclusion:

FFH can act as a pro-oxidative agent and induce the apoptosis of prostate cancer cells.

SUMMARY

Hexane fraction of the methanol extract of Forsythiae Fructus (FFH) at a concentration more than 50 µg/mL significantly reduced PC-3 cell viability

FFH time and dose dependently elevated intracellular ROS levels and increased the proportion of cells arrested in the G₀/G₁ phase

FFH significantly accelerated apoptotic cell death and diminished the protein expression levels of Bcl-2, procaspase-9, and procaspase-3

The protein expression levels of Bax, cytochrome c, and cleaved PARP were increased by FFH, and so was the caspase-3 activity.

Abbreviations used: FF: Forsythiae Fructus; FFM: Methanol extract of Forsythiae Fructus; FFH: Hexane fraction of the methanol extract; DCFH-DA: 2’,7’-dichlorodihydro-fluorescein diacetate.

Predictors for progression of metastatic prostate cancer to castration-resistant prostate cancer in Indians

Background & objectives:

There is lack of data on natural history and progression of prostate cancer (PC) which have implications in the management of the disease. We undertook this retrospective study to analyze factors predicting progression of metastatic PC to castration-resistant prostate cancer (CRPC) in Indian men.

Methods:

Complete records of 223 of the 489 patients with metastatic PC were obtained from computerized data based system in a tertiary care hospital in north India between January 2000 to June 2012. Patients with follow up of < 6 months were excluded. Age (≤ and > 65 yr), baseline PSA (< and ≥ 50 ng/ml), bone scan and Gleason score (≤7 and >7) were recorded. Extent of bone disease (EOD) was stratified according to the number of bone lesions i.e., < 5, 5-10, > 10. CRPC was defined as two consecutive PSA rise of > 50 per cent from nadir or an absolute value of > 5 ng/ml.

Results:

Mean age of patients was 61.5 ± 12.45 yr and their PSA level was 325.6 ± 631.35 ng/dl. Of the 223 patients, 193 (86%) progressed to CRPC at median time of 10.7 (4-124) months. Median follow up was 24 (6-137) months. On univariate and multivariate analyses EOD on bone scan was found to be a significant predictor (P=0.006) for time to CRPC. Median time to CRPC was 10 months (CI 95%, 7.5-12.48) with >10 lesions or super scan versus 16 months (CI 95%, 10.3-21.6) with <10 bone lesion (P=0.01). Ninety (46.6 %) patients of CRPC died with median time to death from time of CRPC 21 (10-120) months.

Interpretation & conclusions:

Median time for progression of metastatic PC to CRPC ranged from 10-16 months depending on the extent of the bone involvement. In Indians, the aggressive course of advanced prostate cancer warrants further clinical trials to explore the need for additional treatment along with initial castration.

Shifting paradigms in the estimation of survival for castration-resistant prostate cancer: A tertiary academic center experience

OBJECTIVES

Castration-resistant prostate cancer (CRPC) has retained a guarded prognosis, with historical survival estimates of 18 to 24 months. However, the landscape of available therapy has changed, and the emphasis has altered from supportive to active treatment. Few large series from real-world populations exist in the contemporary era with fully mature survival data to confirm the indication based on clinical trials that patients with CRPC are surviving far longer than the historical estimates. We aim to review a large patient cohort with CRPC and provide mature survival data.

METHODS AND MATERIALS

Using the electronic histopathology database at Queen Elizabeth Hospital, Birmingham, UK, all prostate-specific antigentest results between April 2006 and September 2007 were extracted, and patients satisfying the American Society for Radiation Oncology (ASTRO) definition of hormone failure were identified. Electronic records were reviewed and variables were collected, including survival, treatment, biochemistry, histopathology, and demographics. Probability of survival, and of developing metastasis or CRPC, was determined using the Kaplan-Meier method. Patients were stratified into 3 groups, namely, D0--no metastasis at diagnosis but later appearance, D1--no metastasis at diagnosis or at last follow-up, and D2--metastasis at diagnosis.

RESULTS

From 8,062 patient-prostate-specific antigen episodes, we identified 447 patients meeting the criteria. A notes review revealed 147 patients with CRPC. Median overall survival (OS) from diagnosis was 84.7 months (95% CI: 73-89), and 129 deaths had occurred (88%). Median OS from diagnosis for D0, D1, and D2 patients was 100.4, 180.1, and 58.9 months, respectively (P< 0.0001), and median OS from CRPC was 40 months (95% CI: 31-58), 82.9 (95% CI: 72-94; P = 0.0125), and 38.7 months (95% CI: 33-46), respectively. One-quarter of patients survived 6 years after development of CRPC. Metastasis is the key prognostic event.

CONCLUSIONS

Some current international guidelines quote ≤19 months as a survival figure for patients with metastatic CRPC. In our study, median survival is more than double this. We have shown survival more than previously reported figures and believe that these data benefit clinicians and patients in understanding prognosis and treatment choices. Importantly, our patients were diagnosed before the current wave of novel therapeutics for CRPC, so survival for men diagnosed today may be more than our findings.

Factors that predict the development of bone metastases due to prostate cancer: Recommendations for follow-up and therapeutic options

CONTEXT

Prostate cancer is a public health problem in Spain and in the Western world. Bone involvement, associated to significant morbidity, is practically constant in the advanced stages of the disease. This work aims to review the prognostic factors used in the usual clinical practice that predict the development of bone metastases and to analyze the follow-up and treatment option in these patient profiles.

ACQUIRING OF EVIDENCE

We performed a review of the literature on the useful factors in the context of therapy with intention to cure. We included the classical clinical values in the diagnosis (PSA, clinical stage, Gleason score on the biopsy) pathological factors (pT stage, margins, bladder invasion, tumor volume, lymph node involvement) and PSA kinetics in their different contexts and the histological and molecular parameters.

SYNTHESIS OF EVIDENCE

The tumor differentiation "Gleason" score and PSA are the most important predictive factors in the prediction of bone metastases in patients with intention to cure. Kinetic factors such as PSA doubling time (TDPSA) < 8 months or PSA > 10 ng/ml in the case of castration-resistant prostate cancer (CPRC), are predictive factors for the development of metastasis. Zoledronic acid and denosumab have demonstrated their effectiveness for the treatment of bone disease in randomized studies.

CONCLUSIONS

There are predictive factors within the usual clinical practice that make it possible to recognize the "patient at risk" to develop bone metastatic disease. The currently available treatments, zoledronic acid or denosumab, can help us in the management of the patient at risk of developing metastasis or metastatic patient, increasing the quality of life and decreasing skeletal events.

Association of stress management skills and perceived stress with physical and emotional well-being among advanced prostrate cancer survivors following androgen deprivation treatment

Advanced prostate cancer (APC) is associated with disruptions that compromise health related quality of life (HRQOL). Treatment often includes androgendeprivation therapy (ADT), which results in a range of side effects (e.g., fatigue, urinary dysfunction) that further impact HRQOL. Despite these challenges, there are limited evaluations of the impact of stress and stress management skills on HRQOL among APC survivors on ADT. This study evaluated relationships among stress, stress management skills, and HRQOL, and it was hypothesized that better stress management skills would relate to greater physical and emotional well-being by mitigating perceived stress levels. Participants (N = 77) were 69.7 years old (SD = 9.8), 18.6 months post-treatment (SD = 17.5), and ethnically diverse (65 % Non-Hispanic White, 13 % Hispanic, 21 % African-American). Measures included the Measure of Current Status for stress management skills, the Perceived Stress Scale for perceived stress, and the Medical Outcomes Study-Short Form (MOS SF-36; physical functioning and emotional well-being subscales) for HRQOL. Direct effects and mediation models were evaluated to determine the relationships between perceived stress, stress management skills, and HRQOL domains, controlling for relevant covariates. Stress management skills and perceived stress were significantly associated with physical functioning (β = .24, p < .05 and β = -.43, p < .01, respectively) and emotional well-being (β = .35, p < .01 and β = -.64, p < .01, respectively). Regression analyses supported the hypothesis that reduced perceived stress mediated the relationship between stress management skills and both physical functioning and emotional well-being. These results demonstrate that one way stress management skills may impact HRQOL is by lessening ongoing perceptions of stress.

Local prostate cancer radiotherapy after prostate-specific antigen progression during primary hormonal therapy

Background

The outcome of patients after radiotherapy (RT) for localized prostate cancer in case of prostate-specific antigen (PSA) progression during primary hormonal therapy (HT) is not well known.

Methods

A group of 27 patients presenting with PSA progression during primary HT for local prostate cancer RT was identified among patients who were treated in the years 2000–2004 either using external-beam RT (EBRT; 70.2Gy; n=261) or Ir-192 brachytherapy as a boost to EBRT (HDR-BT; 18Gy + 50.4Gy; n=71). The median follow-up period after RT was 68 months.

Results

Median biochemical recurrence free (BRFS), disease specific (DSS) and overall survival (OS) for patients with PSA progression during primary HT was found to be only 21, 54 and 53 months, respectively, with a 6-year BRFS, DSS and OS of 19%, 41% and 26%. There were no significant differences between different RT concepts (6-year OS of 27% after EBRT and 20% after EBRT with HDR-BT).

Considering all 332 patients in multivariate Cox regression analysis, PSA progression during initial HT, Gleason score>6 and patient age were found to be predictive for lower OS (p<0.001). The highest hazard ratio resulted for PSA progression during initial HT (7.2 in comparison to patients without PSA progression during primary HT). PSA progression and a nadir >0.5 ng/ml during initial HT were both significant risk factors for biochemical recurrence.

Conclusions

An unfavourable prognosis after PSA progression during initial HT needs to be considered in the decision process before local prostate radiotherapy. Results from other centres are needed to validate our findings.

Cost-effectiveness analysis of stereotactic body radiation therapy versus intensity-modulated radiation therapy: an emerging initial radiation treatment option for organ-confined prostate cancer

PURPOSE

The purpose of this study is to compare the cost-effectiveness of two external beam radiation therapy techniques for treatment of low- to intermediate-risk prostate cancer: stereotactic body radiation therapy (SBRT) and intensity-modulated radiation therapy (IMRT).

MATERIALS AND METHODS

A Markov decision analysis model with probabilistic sensitivity analysis was designed with the various disease states of a 70-year-old patient with organ-confined prostate cancer to evaluate the cost-effectiveness of two external beam radiation treatment options.

RESULTS

The Monte Carlo simulation revealed that the mean cost and quality-adjusted life-years (QALYs) for SBRT and IMRT were $22,152 and 7.9 years and $35,431 and 7.9 years, respectively. The sensitivity analysis revealed that if the SBRT cohort experienced a decrease in quality of life of 4% or a decrease in efficacy of 6%, then SBRT would no longer dominate IMRT in cost-effectiveness. In fact, with these relaxed assumptions for SBRT, the incremental cost-effectiveness ratio of IMRT met the societal willingness to pay threshold of $50,000 per QALY.

CONCLUSION

Compared with IMRT, SBRT for low- to intermediate-risk prostate cancer has great potential cost savings for our health care system payers and may improve access to radiation, increase patient convenience, and boost quality of life for patients. Our model suggests that the incremental cost-effectiveness ratio of IMRT compared with SBRT is highly sensitive to quality-of-life outcomes, which should be adequately and comparably measured in current and future prostate SBRT studies.

Prostate radiation in non-metastatic castrate refractory prostate cancer provides an interesting insight into biology of prostate cancer

Background

The natural history of non-metastatic castrate refractory prostate cancer is unknown and treatment options are limited. We present a retrospective review of 13 patients with locally advanced or high risk prostate cancer, initially treated with hormone monotherapy and then treated with prostate radiation after becoming castration refractory.

Findings

Median PSA response following prostate radiation was 67.4%. Median time to biochemical progression following radiotherapy was 15 months and to detection of metastatic disease was 18.5 months. Median survival from castration resistance (to date of death or November 2011) was 60 months, with median survival from RT 42 months.

Conclusion

Prostate radiation appears to be beneficial even in patients with potential micrometastatic disease, which supports the hypothesis that the primary tumour is important in the progression of prostate cancer. These results are an interesting addition to the literature on the biology of prostate cancer especially as this data is unlikely to be available in the future due to combined prostate radiation and androgen deprivation therapy now being the standard of care.

Individualized strategy for dosing luteinizing hormone-releasing hormone agonists for androgen-independent prostate cancer: identification of outcomes and costs

PURPOSE

Continuing androgen suppression is the current standard in men with androgen-independent prostate cancer (AIPC). An individualized strategy, wherein luteinizing hormone-releasing hormone agonists (LH-RHas) are redosed when serum testosterone approaches a non-castrate level, may decrease costs without worsening outcomes. To understand possible outcomes, we performed a cost-utility analysis comparing individualized and fixed LH-RHa dosing strategies in men with AIPC.

METHODS

The model used a societal perspective, a 5-year time horizon, and 3% annual cost discounting. The model accounted for direct costs of androgen suppression. Utilities were varied in accordance with published preference data.

RESULTS

Under base-case assumptions, individualized LH-RHa dosing yielded 1.089 expected quality-adjusted life years (QALYs), compared with 1.094 expected QALYs for fixed LH-RHa dosing. In cost analysis, lifetime per-patient costs for androgen suppression were estimated to be $5,694 for individualized LH-RHa dosing and $9,157 for fixed LH-RHa dosing. Applied to the total population, a strategy of individualized LH-RHa dosing would cost $170 million for androgen suppression, compared with $274 million for fixed LH-RHa dosing. Under these assumptions, adopting the individualized strategy resulted in $692,600 gained from a societal perspective for each QALY lost (the decremental cost utility).

CONCLUSION

The results suggest that an individualized LH-RHa dosing strategy would be associated with moderate savings on an individual basis but substantial savings on a population basis, and would not adversely affect quality of life or life expectancy. Further research is needed to establish the effects of this strategy on symptoms and survival, as well as patient satisfaction and true costs.

An update on TroVax for the treatment of progressive castration-resistant prostate cancer

Prostate cancer is a common human malignancy with few effective therapeutic options for treating advanced castration-resistant disease. The potential therapeutic effectiveness of immunotherapy and vaccines, in particular, has gained popularity based on the identification of prostate-associated antigens, potent expression vectors for vaccination, and data from recent clinical trials. A modified vaccinia Ankara (MVA) virus expressing 5T4, a tumor-associated glycoprotein, has shown promise in preclinical studies and clinical trials in patients with colorectal and renal cell carcinoma. This review will discuss the rationale for immunotherapy in prostate cancer and describe preclinical and limited clinical data in prostate cancer for the MVA-5T4 (TroVax^®) vaccine.

Comorbidity and competing risks for mortality in men with prostate cancer

BACKGROUND

Accurate estimation of life expectancy is essential for men deciding between aggressive and conservative treatment of prostate cancer. The authors sought to assess the competing risks of nonprostate cancer and prostate cancer mortality among men with differing Charlson comorbidity index scores and tumor risks.

METHODS

The authors conducted a retrospective study of 1482 men with nonmetastatic prostate cancer diagnosed from 1997 to 2004 at the Greater Los Angeles and Long Beach Veterans Affairs Medical Centers. They performed Kaplan-Meier and competing risks regression analyses to assess survival outcomes.

RESULTS

After a mean follow-up of 6.0 years, 370 (25%) men died from other causes, whereas 44 (3%) died of prostate cancer. At 10 years after diagnosis, men with Charlson scores 0, 1, 2, and 3+ had nonprostate cancer mortality rates of 17%, 34%, 52%, and 74%, respectively. In competing risks regression analysis, each point increase in Charlson score was associated with a 2-fold increase in hazard of nonprostate mortality. Men with Charlson 3+ had 8.5× the hazard of death from other causes, compared with men with the lowest scores (subhazard ratio, 8.5; 95% confidence interval, 6.2-11.7). After stratification by tumor risk, nonprostate mortality rates remained markedly elevated among men with higher Charlson scores, whereas prostate cancer mortality was rare, especially among low-risk and intermediate-risk groups (0.4%, 3%, and 8% for low, intermediate, and high risk, respectively).

CONCLUSIONS

Men with the highest Charlson scores should consider conservative management of low-risk and intermediate-risk tumors, given their exceedingly high risk of death from other causes and low risk of prostate cancer mortality.

eIF4E phosphorylation promotes tumorigenesis and is associated with prostate cancer progression

Translational regulation plays a critical role in the control of cell growth and proliferation. A key player in translational control is eIF4E, the mRNA 5' cap-binding protein. Aberrant expression of eIF4E promotes tumorigenesis and has been implicated in cancer development and progression. The activity of eIF4E is dysregulated in cancer. Regulation of eIF4E is partly achieved through phosphorylation. However, the physiological significance of eIF4E phosphorylation in mammals is not clear. Here, we show that knock-in mice expressing a nonphosphorylatable form of eIF4E are resistant to tumorigenesis in a prostate cancer model. By using a genome-wide analysis of translated mRNAs, we show that the phosphorylation of eIF4E is required for translational up-regulation of several proteins implicated in tumorigenesis. Accordingly, increased phospho-eIF4E levels correlate with disease progression in patients with prostate cancer. Our findings establish eIF4E phosphorylation as a critical event in tumorigenesis. These findings raise the possibility that chemical compounds that prevent the phosphorylation of eIF4E could act as anticancer drugs.

Cost-effectiveness of intensity-modulated radiation therapy

Technical advances have given medicine the opportunity to refine current treatment techniques to improve outcomes. Computed tomography, magnetic resonance imaging and high energy linear accelerators are but a few examples of technology translating into clinical practice. Intensity-modulated radiation therapy is a form of 3D conformal radiation that is being increasingly incorporated into the management of patients with prostate cancer. As with any new technology, the cost of intensity-modulated radiation therapy is considerably greater than standard therapy. Economic models can be useful to compare treatments when this comparison cannot be performed in a clinical trial. A Markov Model was used to compare the use of intensity-modulated radiation with 3D conformal radiation therapy in the treatment of a 70 year old man with a good- and intermediate-risk prostate cancer. Cost data for men with Medicare insurance and prostate cancer treated with intensity-modulated radiation therapy and 3D conformal radiation therapy was obtained from the billing department at the Fox Chase Cancer Center (PA, USA). Utilities were collected from men undergoing intensity-modulated radiation therapy and 3D conformal radiation therapy for prostate cancer. Intensity-modulated radiation therapy was found to be cost effective in the treatment of a 70 year old man with prostate cancer with a incremental cost-effectiveness ratio of USD 16,182/quality-adjusted life year for men with intermediate-risk prostate cancer and USD 17,448/ quality-adjusted life year for men with good-risk prostate cancer. Sensitivity analysis found that a longer time horizon of the analysis and younger age at treatment favorably impact the cost-effectiveness ratio.

Radiotherapy for patients with localized hormone-refractory prostate cancer: results of the Patterns of Care Study in Japan

OBJECTIVE

To evaluate the clinical results of radiotherapy (RT) for patients with regionally localized hormone-refractory prostate carcinoma (HRPC).

PATIENTS AND METHODS

As part of a Patterns of Care Study in Japan, a nationwide survey was conducted of RT for patients with prostate adenocarcinoma. We reviewed the detailed information of 140 patients with regionally localized HRPC who received RT between 1996 and 1998, and between 1999 and 2001, in 117 randomly selected institutes in Japan. The median (range) age of the patients was 74 (51-94) years, and their tumours were defined as well (14), moderately (51) or poorly (54) differentiated, or of unknown differentiation (21). The median (range) interval between hormonal therapy (HT) and RT was 32.5 (1.1-168.4) months. Ninety-five patients had T3-4 tumours and 28 had regional lymph node metastases before treatment. The median (range) prostate-specific antigen levels before the initial HT and before RT were 35.0 (1.5-276) and 10.0 (0.06-760.3) ng/mL, respectively. External beam RT was administered, with a median total dose of 66 Gy; 70 patients (50%) received pelvic irradiation.

RESULTS

At a median follow-up of 20.7 months, the 5-year overall and clinical progression-free survival rates (95% confidence interval) were 48.1 (36-60)% and 36.7 (26-47)%, respectively. Although there were distant metastases in 46 patients, only six had local progression. There was late morbidity of grade > or =3 in six patients.

CONCLUSION

To the best of our knowledge, this study comprises the largest series of regionally localized HRPC treated with RT reported to date. RT might have a limited role for HRPC, because in most patients RT failed, with distant metastasis.

Systemic therapy for advancing or metastatic prostate cancer (STAMPEDE): a multi-arm, multistage randomized controlled trial

There is a need to improve the outcomes for men with high-risk localised, nodal or metastatic prostate cancer, or with aggressively relapsing disease after initial therapy for local disease. This group of men is currently managed with long-term hormone therapy. Thus we aim to evaluate the toxicity and efficacy of three different systemic therapies (docetaxel, zoledronic acid and celecoxib) used alone or combined at the initiation of hormone manipulation for high-risk prostate cancer. A novel statistical design (multi-arm, multistage method) simultaneously tests multiple distinct strategies in parallel against a single control arm. The trial has several 'stages', from initial confirmation of safety to a phase III assessment of survival, with a series of intervening activity stages. This method provides a means of assessing several agents more quickly and efficiently, and allows inactive treatments to be dropped from further study at an early stage. STAMPEDE has been designed to address in parallel the activity and efficacy of these agents for this patient group. It is a flagship randomized clinical trial for academic research into prostate cancer in the UK. More than 500 patients have been recruited on schedule, confirming the acceptability of this complex trial design to patients and clinicians. The trial targets a population of approximately 3000 patients. STAMPEDE is a major new trial with a novel design applicable to the synchronous testing of several agents. It is hoped that the results will improve outcomes for patients with high-risk prostate cancer. The design could be applicable to the study of new therapies in other cancer types. Continued efforts are required by the urological cancer community to maintain the excellent recruitment shown to date.

Current perspectives in the treatment of advanced prostate cancer

Prostate cancer (PC) continues to be an important world health problem for men. Patients with locally confined PC are treated with either radiotherapy or surgery. However, treatment of more advanced stages of the disease is problematic. Initially, androgen deprivation offers a period of clinical stability, which is however invariably followed by progression to non-responsiveness to hormonal manipulation. Current management of patients with androgen-independent prostate cancer (AIPC) displays modest response rates and achieves only short-term benefit. Recently, knowledge in the complex pathophysiology of advanced PC has led to the identification of mechanisms and target molecules permitting the introduction of new therapies. Consequently, many investigational treatments are ongoing for AIPC in Phase-II and Phase-III trials aiming at the combination of chemotherapeutic regimens along with immunotherapy targeting PC-associated antigens. Other attractive options are gene therapy, as well as the targeting of survival signaling, differentiation, and apoptosis of the malignant PC cells. Further treatment modalities are directed against the tumor microenvironment, bone metastasis, or both. Collectively, the aforementioned efforts introduce a new era in the management of advanced PC. Novel pharmaceutical compounds and innovative approaches, integrated into the concept of individualized therapy will hopefully, during the next decade, improve the outcome and survival for hundreds of thousands of men worldwide.

Association of a CYP17 polymorphism with overall survival in Caucasian patients with androgen-independent prostate cancer

OBJECTIVES

To investigate the association between a cytochrome P450 17alpha-hydroxylase gene (CYP17) polymorphism and survival in Caucasian patients with androgen-independent prostate cancer (AIPC).

METHODS

The study used 222 samples acquired from Caucasian patients with AIPC. The CYP17 polymorphism (-34T>C) was analyzed using polymerase chain reaction amplification followed by restriction fragment length polymorphism detection.

RESULTS

No significant differences were observed in the frequencies of the CYP17 genotype in relation to categorized Gleason scores, age at diagnosis, or hormone therapy. The median survival was significantly longer in 126 patients with the CYP17 A2 allele (8.9 years) genotype than in 96 patients with the A1 allele (6.7 years) genotype (P = 0.040 by log-rank test). Similarly, the estimated survival probability at 10 years (24% in A1 allele versus 43% in A2 allele) showed a statistically significant difference between the two groups (P = 0.002 by the permutation test).

CONCLUSIONS

These results suggest that the CYP17 polymorphism is associated with overall survival in patients with AIPC.

Is proton beam therapy cost effective in the treatment of adenocarcinoma of the prostate?

PURPOSE

New treatments are introduced routinely into clinical practice without rigorous economic analysis. The specific aim of this study was to examine the cost effectiveness of proton beam radiation compared with current state-of-the art therapy in the treatment of patients with prostate cancer.

MATERIALS AND METHODS

A Markov model was informed with cost, freedom from biochemical failure (FFBF), and utility data obtained from the literature and from patient interviews to compare the cost effectiveness of 91.8 cobalt gray equivalent (CGE) delivered with proton beam versus 81 CGE delivered with intensity-modulated radiation therapy (IMRT). The length of how many years the model was run, patient's age, probability of FFBF after treatment with proton beam therapy and IMRT, utility of patients treated with salvage hormone therapy, and treatment cost were tested in sensitivity analyses.

RESULTS

Analysis at 15 years resulted in an expected mean cost of proton beam therapy and IMRT of $63,511 and $36,808, and $64,989 and $39,355 for a 70-year-old and 60-year-old man respectively, with quality-adjusted survival of 8.54 and 8.12 and 9.91 and 9.45 quality-adjusted life-years (QALY), respectively. The incremental cost effectiveness ratio was calculated to be $63,578/QALY for a 70-year-old man and $55,726/QALY for a 60-year-old man.

CONCLUSION

Even when based on the unproven assumption that protons will permit a 10-Gy escalation of prostate dose compared with IMRT photons, proton beam therapy is not cost effective for most patients with prostate cancer using the commonly accepted standard of $50,000/QALY. Consideration should be given to limiting the number of proton facilities to allow comprehensive evaluation of this modality.

Suppression of androgen receptor-mediated gene expression by a sequence-specific DNA-binding polyamide

Androgen receptor (AR) is essential for the growth and progression of prostate cancer in both hormone-sensitive and hormone-refractory disease. A DNA-binding polyamide that targets the consensus androgen response element binds the prostate-specific antigen (PSA) promoter androgen response element, inhibits androgen-induced expression of PSA and several other AR-regulated genes in cultured prostate cancer cells, and reduces AR occupancy at the PSA promoter and enhancer. Down-regulation of PSA by this polyamide was comparable to that produced by the synthetic antiandrogen bicalutamide (Casodex) at the same concentration. Genome-wide expression analysis reveals that a similar number of transcripts are affected by treatment with the polyamide and with bicalutamide. Direct inhibition of the AR-DNA interface by sequence-specific DNA binding small molecules could offer an alternative approach to antagonizing AR activity.

An HSV-1 amplicon system for prostate-specific expression of ICP4 to complement oncolytic viral replication for in vitro and in vivo treatment of prostate cancer cells

The aim of the present study was to determine whether a prostate-specific amplicon, containing a probasin-derived promoter (ARR(2)PB) upstream of an essential Herpes simplex virus-1 (HSV-1) viral gene, infected-cell polypeptide 4 (ICP4), could complement an HSV-1 helper virus with this gene deleted (ICP4-) and cause lytic replication specifically in prostate cancer cells. Two amplicon constructs, CMV-ICP4 and ARR(2)PB-ICP4, were packaged by a replication-deficient ICP4- helper virus. The amplicon viruses could complement ICP4- helper viruses to efficiently replicate and cause cell lysis in prostate cancer cells. Intratumoral injection of LNCaP human prostate cancer xenografts with either amplicon/helper virus resulted in >75% reduction in tumor volume and serum prostate specific antigen (PSA). Histological and Q-PCR (quantitative PCR) analyses indicated that the toxicity in nontumor tissues was much lower with ARR(2)PB-ICP4 than with CMV-ICP4 amplicon/helper virus. In conclusion, a replication-deficient HSV-1 virus could be complemented by an amplicon virus to restore its oncolytic activity in a tissue-specific and low toxicity fashion, illustrating that this approach could be a potentially useful strategy for developing an oncolytic viral therapy for prostate cancer.

Update in palliative management of hormone refractory cancer of prostate

Hormone refractory prostate cancer (HRPC) is an incurable disease and as in the pressure sensitive adhesive era the median survival of patients is increasing, these men increasingly develop symptomatic problems as a result of advanced local and or metastatic disease during their progression to death. Recently, it has been shown that it is possible to improve survival in this group of patients with use of chemotherapy which reinforces the need of better options in palliative care. We discus the various clinical problems (Part I) and treatment options of palliative care (Part II) and try to formulate an action plan in this review.

Prostate-specific antigen doubling time is associated with survival in men with hormone-refractory prostate cancer

OBJECTIVES

Men with metastatic hormone-refractory prostate cancer (HRPC) form a heterogeneous population with a wide range of symptoms and variable survival. Patient selection is critical in determining which patients will receive the most benefit from aggressive chemotherapy. The prostate-specific antigen (PSA) doubling time (PSADT) has been shown to be a surrogate for survival in earlier stages of prostate cancer, but its utility as a predictor in HRPC is unknown.

METHODS

A retrospective chart review of 224 patients with HRPC treated from 1998 to 2002 was performed. Eligible patients had HRPC and evidence of metastatic disease. The PSADT at HRPC diagnosis was calculated, and the optimal PSADT stratification was obtained using the log-rank chi-square statistic. Kaplan-Meier curves were used to estimate overall survival between the groups.

RESULTS

During the follow-up period, 80% of patients died, 93% of prostate cancer. Overall, the median survival from diagnosis of HRPC was 15.1 months (range 0.5 to 90.5). The optimal PSADT stratification for survival was 70 days. Patients with a PSADT of 70 days or less survived 11 months compared with 19 months for those with a PSADT of more than 70 days [relative risk (RR) 1.79, P <0.0001].

CONCLUSIONS

PSADT serves as an independent prognostic marker for survival in patients with metastatic HRPC. Men with a PSADT of 70 days or less had a significantly shorter survival time compared with men with a PSADT of more than 70 days. Inclusion of PSADT with other clinical data could help clinicians select men at high risk of early mortality who may most benefit from aggressive treatment regimens, such as docetaxel-based regimens.

Management of the Spectrum of Hormone Refractory Prostate Cancer

INTRODUCTION

In its advanced stages, hormone refractory prostate cancer (HRPC) is an incurable condition which consists of a spectrum of disease. This requires an integrated multidisciplinary approach by an uro-oncologic team supported by radiologists, skeletal surgeons and palliative care. Aim of this review was to critically evaluate the current and potential approaches to patients affected by HRPC.

MATERIALS AND METHODS

A comprehensive evaluation of available published data included analysis of published full-length papers that were identified with Medline and Cancerlit from January 1981 to January 2006. Official proceedings of internationally known scientific societies held in the same time period were also assessed.

RESULTS

Most men with hormone refractory prostate cancer will die of their disease in the absence of intercurrent illness, and the various conditions arising as a consequence of local and distal cancer progression commonly lead to a spectrum of morbidity requiring treatment. Recent data regarding docetaxel-based chemotherapy have shown small but significant improvements in survival and improvement in quality of life in men receiving treatment. However, this therapy may not be suitable for all patients. New agents used alone or in combination with docetaxel currently are under trial in an attempt to provide much needed improvements in outcome. Bone-targeted treatments, particularly late-generation bisphosphonates, have added to the range of options, reducing the incidence of skeletal complications in some men. Further work is needed to target their use more effectively, to explore their efficacy in combination with existing proven therapies and to develop new approaches to treat bone metastases. Complications arising as a consequence of upper and lower tract dysfunction, haematologic, neurologic and psychologic disorders are common. These complications often are amenable to effective treatment, but interventions may engender difficult clinical and ethical decisions.

CONCLUSIONS

Although HRPC is incurable, it is not untreatable, and that the clinical management embraces not just chemotherapy, but many interventional and supportive therapies. A holistic and supportive approach to patient care is vital for optimal management, and is best provided by a coordinated, multidisciplinary team including urologists and oncologists.

Using decision analysis to determine the cost-effectiveness of intensity-modulated radiation therapy in the treatment of intermediate risk prostate cancer

BACKGROUND

The specific aim of this study is to evaluate the cost-effectiveness of intensity-modulated radiation therapy (IMRT) compared with three-dimensional conformal radiation therapy (3D-CRT) in the treatment of a 70-year-old with intermediate-risk prostate cancer.

METHODS

A Markov model was designed with the following states; posttreatment, hormone therapy, chemotherapy, and death. Transition probabilities from one state to another were calculated from rates derived from the literature for IMRT and 3D-CRT. Utility values for each health state were obtained from preliminary studies of preferences conducted at Fox Chase Cancer Center. The analysis took a payer's perspective. Expected mean costs, cost-effectiveness scatterplots, and cost acceptability curves were calculated with commercially available software.

RESULTS

The expected mean cost of patients undergoing IMRT was $47,931 with a survival of 6.27 quality-adjusted life years (QALYs). The expected mean cost of patients having 3D-CRT was $21,865 with a survival of 5.62 QALYs. The incremental cost-effectiveness comparing IMRT with CRT was $40,101/QALYs. Cost-effectiveness acceptability curve analysis revealed a 55.1% probability of IMRT being cost-effective at a $50,000/QALY willingness to pay.

CONCLUSION

Intensity-modulated radiation therapy was found to be cost-effective, however, at the upper limits of acceptability. The results, however, are dependent on the assumptions of improved biochemical disease-free survival with fewer patients undergoing subsequent salvage therapy and improved quality of life after the treatment. In the absence of prospective randomized trials, decision analysis can help inform physicians and health policy experts on the cost-effectiveness of emerging technologies.

Advancing prostate cancer: treatment options for the urologist

Today's urologists often face the dilemma of how to treat patients who have advancing prostate cancer. The diversity of this patient population makes treatment decisions challenging. For over 60 years the mainstay of treatment for patients who have advancing prostate cancer has been androgen deprivation therapy. Now there are new chemotherapeutic options, novel hormone manipulations, and other adjunctive therapies available. Based on a case presentation, the authors have attempted to outline for the practicing urologist, a logical progression of treatment options for advancing prostate cancer.

A novel biomarker for staging human prostate adenocarcinoma: overexpression of matriptase with concomitant loss of its inhibitor, hepatocyte growth factor activator inhibitor-1

BACKGROUND

Matriptase, a type II transmembrane serine protease is involved in angiogenesis, degradation of extracellular matrix, and in the progression of some epithelial cancers. Here, we establish the clinical significance of matriptase and its inhibitor, hepatocyte growth factor activator inhibitor-1 (HAI-1), during the progression of human prostate cancer (CaP).

METHODS

The expression patterns of matriptase and HAI-1 were determined in primary cultures of normal human prostate epithelial (NHPE) cells, human CaP cells LNCaP, DU-145, CWR22Rnu1, and PC-3, and in tissue samples of 172 patients with normal prostate, benign prostatic hyperplasia (BPH), prostatic intraepithelial neoplasia (PIN), and adenocarcinoma of different tumor grades.

RESULTS

The protein and mRNA levels of matriptase were significantly higher in all carcinoma cells as compared with NHPE cells. Conversely, all CaP cells exhibited a reduced expression of HAI-1 as compared with NHPE cells. A progressive increase in the protein levels of matriptase was observed with increasing tumor grade in CaP specimens as compared with normal and BPH tissue specimens. Tissue samples of normal prostate exhibited a high constitutive protein level of HAI-1 compared with BPH and low-grade cancer with a progressive loss with increasing tumor grade.

CONCLUSION

The increased expression of matriptase and loss of HAI-1 may be an important event during the progression of CaP in humans. We suggest that the ratio of these two gene products may serve as a promising biomarker for CaP progression and a potential marker for establishing the efficacy of therapeutic and chemopreventive interventions.

Androgen receptor as a therapeutic target for androgen independent prostate cancer

Prostate cancer is the leading cause of nonskin malignancy and the second leading cause of cancer death in men. Androgen deprivation therapy is the first-line of systemic therapy against advanced prostate cancer. All advanced prostate cancers eventually grow despite castrate levels of testosterone. We review the evidence that androgen independent prostate cancer continues to require androgen receptor activity for growth, the mechanisms of androgen receptor activation in the castrate setting, and possible points of intervention for novel therapies targeting the androgen receptor and prostate cancer.

Pre-treatment nomogram for disease-specific survival of patients with chemotherapy-naive androgen independent prostate cancer

OBJECTIVE

Our objective was to develop a nomogram that predicts the probability of cancer-specific survival in men with untreated androgen-independent prostate cancer (AIPC).

METHODS

AIPC was diagnosed in 129 consecutive patients between 1989 and 2002. No patient received cytotoxic chemotherapy. Univariate and multivariate Cox regression models were used to test the association between prostate-specific antigen (PSA) level at initiation of androgen deprivation, PSA doubling time (PSADT), PSA nadir on androgen deprivation therapy (ADT), time from ADT to AIPC, and AIPC-specific mortality. Multivariate regression coefficients were then used to develop a nomogram predicting AIPC-specific survival at 12-60 mo after AIPC diagnosis. Two-hundred bootstrap resamples were used to internally validate the nomogram.

RESULTS

AIPC-specific mortality was recorded in 74 of 129 patients (57.4%). Other-cause mortality was recorded in 7 men (5.4%). Median overall survival was 52.0 mo (mean, 36.0 mo) and median AIPC-specific survival was 54.0 mo (mean, 35.0 mo). In univariate regression models, all variables were significant predictors of AIPC-specific survival (p < or = 0.02). In multivariate models, PSADT and time from androgen deprivation to AIPC remained statistically significant (p < or = 0.004). Bootstrap-corrected predictive accuracy of the nomogram was 80.9% versus 74.9% for our previous model.

CONCLUSIONS

A nomogram predicting AIPC-specific survival is between 13% and 14% more accurate than previous nomograms and 6% more accurate than tree regression-based predictions obtained from the same data. Moreover, a nomogram approach combines several advantages, such as user-friendly interface and precise estimation of individual recurrence probability at several time points after AIPC diagnosis, which all patients deserve to know and all treating physicians need to know.

Economic analysis of a phase III clinical trial evaluating the addition of total androgen suppression to radiation versus radiation alone for locally advanced prostate cancer (Radiation Therapy Oncology Group protocol 86-10)

PURPOSE

To evaluate the cost-effectiveness of adding hormone therapy to radiation for patients with locally advanced prostate cancer, using a Monte Carlo simulation of a Markov Model.

METHODS AND MATERIALS

Radiation Therapy Oncology Group (RTOG) protocol 86-10 randomized patients to receive radiation therapy (RT) alone or RT plus total androgen suppression (RTHormones) 2 months before and during RT for the treatment of locally advanced prostate cancer. A Markov model was designed with Data Pro (TreeAge Software, Williamstown, MA). The analysis took a payer's perspective. Transition probabilities from one state of health (i.e., with no disease progression or with hormone-responsive metastatic disease) to another were calculated from published rates pertaining to RTOG 86-10. Patients remained in one state of health for 1 year. Utility values for each health state and treatment were obtained from the literature. Distributions were sampled at random from the treatment utilities according to a second-order Monte Carlo simulation technique.

RESULTS

The mean expected cost for the RT-only treatments was 29,240 dollars (range, 29,138-29,403 dollars). The mean effectiveness for the RT-only treatment was 5.48 quality-adjusted life years (QALYs) (range, 5.47-5.50). The mean expected cost for RTHormones was 31,286 dollars (range, 31,058-31,555 dollars). The mean effectiveness was 6.43 QALYs (range, 6.42-6.44). Incremental cost-effectiveness analysis showed RTHormones to be within the range of cost-effectiveness at 2,153 dollars/QALY. Cost-effectiveness acceptability curve analysis resulted in a >80% probability that RTHormones is cost-effective.

CONCLUSIONS

Our analysis shows that adding hormonal treatment to RT improves health outcomes at a cost that is within the acceptable cost-effectiveness range.

Prostate size and risk of high-grade, advanced prostate cancer and biochemical progression after radical prostatectomy: a search database study

PURPOSE

Prostate growth and differentiation are under androgenic control, and prior studies suggested that tumors that develop in hypogonadal men are more aggressive. We examined whether prostate weight was associated with tumor grade, advanced disease, or risk of biochemical progression after radical prostatectomy (RP).

PATIENTS AND METHODS

We evaluated the association of prostate weight with pathologic tumor grade, positive surgical margins, extracapsular disease, and seminal vesicle invasion using logistic regression and with biochemical progression using Cox proportional hazards regression among 1,602 men treated with RP between 1988 and 2003 at five equal-access medical centers, which composed the Shared Equal Access Regional Cancer Hospital (SEARCH) Database.

RESULTS

In outcome prediction models including multiple predictor variables, it was found that the predictor variable of prostate weight was significantly inversely associated with the outcomes of high-grade disease, positive surgical margins, extracapsular extension (all P < or = .004), and biochemical progression (comparing prostate weight < 20 v > or = 100 g: relative risk = 8.43; 95% CI, 2.9 to 24.0; P < .001). Similar associations were seen between preoperative transrectal ultrasound-measured prostate volume and high-grade disease, positive surgical margins, extracapsular extension (all P < or = .005), seminal vesicle invasion (P = .07), and biochemical progression (P = .06).

CONCLUSION

Men with smaller prostates had more high-grade cancers and more advanced disease and were at greater risk of progression after RP. These results suggest that prostate size may be an important prognostic variable that should be evaluated for use pre- and postoperatively to predict biochemical progression.

A retrospective study of the time to clinical endpoints for advanced prostate cancer

OBJECTIVE

To determine the natural history of patients with prostate cancer who start initial androgen-deprivation therapy (ADT) for biochemical failure with no radiographic evidence of disease (D0) or with radiographic metastatic disease (D2), as the history is either not well-defined or is changing, and such data are critical for guiding therapy after prostate cancer recurrence.

PATIENTS AND METHODS

We retrospectively assessed the time to androgen-independence (AI), defined as the first sustained rise in prostate-specific antigen (PSA) level on ADT, time to metastatic disease and overall survival for 80 patients with metastatic prostate cancer in clinical trials at the National Cancer Institute.

RESULTS

ADT was initiated after metastatic disease in 37 patients and before metastatic disease in 43 patients; in these 43 patients, the median time to developing metastatic disease on ADT was 37.8 months. The median time to AI from the initiation of ADT was 19.3 and 13.1 months in D0 and D2 patients, respectively. The median overall survival from the start of ADT was 89.0 and 63.0 months, and the median overall survival from the time of AI was 63.1 and 44.2 months in D0 and D2 patients, respectively. These 80 patients, which included 43 who had no metastatic disease when starting ADT, had a median survival of 54.8 months after AI prostate cancer.

CONCLUSIONS

We describe the natural history of AI prostate cancer in D0 patients who eventually developed metastasis, and in D2 patients. The results suggest a longer than expected survival with AI prostate cancer, and to our knowledge this is the first study to report the time to metastatic disease for D0 patients from ADT and from AI. These results can be used to help design clinical trials in patients with D0 prostate cancer.

Relationships between reverse transcriptase-polymerase chain reaction for prostate specific antigen, survival, and various prognostic laboratory factors in patients with hormone refractory prostate cancer

The detection of prostate-specific antigen (PSA) mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR) in the bloodstream of prostate cancer patients has been hypothesized as a prognostic marker, however little data are available concerning the association between this molecular marker and other laboratory values of potential importance. In this study, in patients with hormone-refractory prostate cancer (HRPC), relationships were determined between PSA RT-PCR positivity, survival, and various relevant markers including serum PSA, LDH, albumin, alkaline phosphatase and hemoglobin. A total of 19/30 HRPC patients were positive for PSA by RT-PCR. Positivity was significantly linked to serum PSA (P=0.004) and serum alkaline phosphatase (P=0.026) but not to the other laboratory variables. Median survival time for RT-PCR-positive patients was 9 months, compared to 19 months for RT-PCR-negative patients (P=0.035). Median survival time for patients with a hemoglobin>or=11 g/dL was 12 months, compared to 9 months for patients with <11 g/dL (P=0.005). Dichotomized (>or=or<median) serum PSA, LDH, alkaline phosphatase, and albumin were not significantly associated with survival in univariate analyses. In multivariate analysis, only dichotomized hemoglobin (<11 g/dL vs. >or=11 g/dL) remained statistically significant (P=0.019), indicating that RT-PCR had no independent association with survival after controlling for hemoglobin status in this study.

Second-Line Chemotherapy for Hormone-Refractory Prostate Cancer: Has the Time Come?

Prostate-specific antigen testing has not only led to an earlier diagnosis of prostate cancer, but also to an earlier identification of hormone-refractory prostate cancer (HRPC). Many patients identified early with HRPC may receive first-line taxane-based chemotherapy. Patients who progress after first-line chemotherapy are still quite healthy and desire further therapy. No proven treatment options exist for the second-line treatment of HRPC. Finding new agents that are active in the second-line setting and identifying relevant outcome variables and predictive pretreatment variables are crucial in improving survival and quality of life for this patient population.