Assessment of endpoints for clinical trials for localized prostate cancer

A scoping review of core outcome sets and their 'mapping' onto real-world data using prostate cancer as a case study

Background

A Core Outcomes Set (COS) is an agreed minimum set of outcomes that should be reported in all clinical studies related to a specific condition. Using prostate cancer as a case study, we identified, summarized, and critically appraised published COS development studies and assessed the degree of overlap between them and selected real-world data (RWD) sources.

Methods

We conducted a scoping review of the Core Outcome Measures in Effectiveness Trials (COMET) Initiative database to identify all COS studies developed for prostate cancer. Several characteristics (i.e., study type, methods for consensus, type of participants, outcomes included in COS and corresponding measurement instruments, timing, and sources) were extracted from the studies; outcomes were classified according to a predefined 38-item taxonomy. The study methodology was assessed based on the recent COS-STAndards for Development (COS-STAD) recommendations. A ‘mapping’ exercise was conducted between the COS identified and RWD routinely collected in selected European countries.

Results

Eleven COS development studies published between 1995 and 2017 were retrieved, of which 8 were classified as ‘COS for clinical trials and clinical research’, 2 as ‘COS for practice’ and 1 as ‘COS patient reported outcomes’. Recommended outcomes were mainly categorized into ‘mortality and survival’ (17%), ‘outcomes related to neoplasm’ (18%), and ‘renal and urinary outcomes’ (13%) with no relevant differences among COS study types. The studies generally fulfilled the criteria for the COS-STAD ‘scope specification’ domain but not the ‘stakeholders involved’ and ‘consensus process’ domains. About 72% overlap existed between COS and linked administrative data sources, with important gaps. Linking with patient registries improved coverage (85%), but was sometimes limited to smaller follow-up patient groups.

Conclusions

This scoping review identified few COS development studies in prostate cancer, some quite dated and with a growing level of methodological quality over time. This study revealed promising overlap between COS and RWD sources, though with important limitations; linking established, national patient registries to administrative data provide the best means to additionally capture patient-reported and some clinical outcomes over time. Thus, increasing the combination of different data sources and the interoperability of systems to follow larger patient groups in RWD is required.

A core outcome set for localised prostate cancer effectiveness trials: protocol for a systematic review of the literature and stakeholder involvement through interviews and a Delphi survey

Background

Prostate cancer is a growing health problem worldwide. The management of localised prostate cancer is controversial. It is unclear which of several surgical, radiotherapeutic, ablative, and surveillance treatments is the most effective. All have cost, process and recovery, and morbidity implications which add to treatment decision-making complexity for patients and healthcare professionals. Evidence from randomised controlled trials (RCTs) is not optimal because of uncertainty as to what constitutes important outcomes. Another issue hampering evidence synthesis is heterogeneity of outcome definition, measurement, and reporting. This project aims to determine which outcomes are the most important to patients and healthcare professionals, and use these findings to recommend a standardised core outcome set for comparative effectiveness trials of treatments for localised prostate cancer, to optimise decision-making.

Methods/Design

The range of potentially important outcomes and measures will be identified through systematic reviews of the literature and semi-structured interviews with patients. A consultation exercise involving representatives from two key stakeholder groups (patients and healthcare professionals) will ratify the list of outcomes to be entered into a three round Delphi study. The Delphi process will refine and prioritise the list of identified outcomes. A methodological substudy (nested RCT design) will also be undertaken. Participants will be randomised after round one of the Delphi study to one of three feedback groups, based on different feedback strategies, in order to explore the potential impact of feedback strategies on participant responses. This may assist the design of a future core outcome set and Delphi studies. Following the Delphi study, a final consensus meeting attended by representatives from both stakeholder groups will determine the final recommended core outcome set.

Discussion

This study will inform clinical practice and future trials of interventions of localised prostate cancer by standardising a core outcome set which should be considered in comparative effectiveness studies for localised prostate cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-015-0598-0) contains supplementary material, which is available to authorized users.

Modeling potential time to event data with competing risks

Patients receiving radical prostatectomy are at risk of metastasis or prostate cancer related death, and often need repeated clinical evaluations to determine whether additional adjuvant or salvage therapies are needed. Since the prostate cancer is a slowly progressing disease, and these additional therapies come with significant side effects, it is important for clinical decision making purposes to estimate a patient's risk of cancer metastasis, in the presence of a competing risk by death, under the hypothetical condition that the patient does not receive any additional therapy. In observational studies, patients may receive additional therapy by choice; the time to metastasis without any therapy is often a potential outcome and not always observed. We study the competing risks model of Fine and Gray (J Am Stat Assoc, 94:496-509, 1999) with adjustment for treatment choice by inverse probability censoring weighting (IPCW). The model can be fit using standard software for partial likelihood with double IPCW weights. The proposed methodology is used in a prostate cancer study to predict the post-prostatectomy cumulative incidence probability of cancer metastasis without additional adjuvant or salvage therapies.

Management of low risk and low PSA prostate cancer: long term results from the prostate cancer intervention versus observation trial

Management of localized prostate cancer is controversial due in part to the lack of randomized controlled trial information in men diagnosed with prostate specific antigen (PSA) testing. Men with low risk or low PSA (<10 ng/ml) prostate cancer comprise up to 70 % of men currently diagnosed. Evidence suggests an excellent long-term prognosis with observation though nearly 90 % are treated with surgery (radical prostatectomy), external beam radiation, or brachytherapy. Results from the Prostate cancer Intervention Versus Observation Trial (PIVOT) provide high quality Level 1 evidence that observation compared to surgery results in similar long-term overall and prostate cancer survival, prevention of bone metastases and avoidance of surgery related harms. Combined with emerging evidence from screening, natural history, decision analysis and cost-effectiveness modeling studies, these data demonstrate that observation is the preferred treatment option for men with low risk and possibly low PSA prostate cancer. Recommending against PSA testing or, in men who still desire testing, raising thresholds of PSA values used to define abnormal, lengthening intervals between PSA tests and discontinuing testing in men with a life expectancy less than 15 years will reduce diagnostic and treatment related harms without adversely impacting overall or disease specific mortality and morbidity.

Ascertaining cause of death among men in the Prostate Cancer Intervention Versus Observation Trial

Background

The Prostate Cancer Intervention Versus Observation Trial (PIVOT) randomized 731 men with localized prostate cancer to radical prostatectomy or observation.

Purpose

We describe the methods and results for cause-of-death assignments in PIVOT, and compare them to alternative strategies for ascertaining prostate cancer–specific mortality, as well as to the methods and results in the similar Scandinavian Prostate Cancer Group Study 4 (SPCG-4) trial.

Methods

Three PIVOT Endpoints Committee members, blinded to randomized treatment assignments, reviewed medical records and death certificates when available to assign a cause of death using a primary and a secondary adjudication question. Initial disagreements were resolved through discussion. The level of initial agreement among committee members was examined, as well as guesses at randomized treatment assignments for a convenience sample of cases. Final cause of death determinations were compared to death certificates.

Results

Complete agreement on cause of death by all three committee members before any discussion was achieved in 200/354 (56%) cases on the primary and 209/354 (59%) cases on the secondary. However, complete agreement on the primary rose to 306/354 (86%) when ‘definite’ and ‘probably’ categories were collapsed, as planned a priori. The three committee members’ proportions of correct guesses of randomized treatment assignment were 82/121 (68%), 113/148 (76%), and 99/134 (74%). Using the committee’s final adjudications as a gold standard, death certificates had suboptimal sensitivities, specificities, or predictive values depending on how they were used to determine cause of death.

Limitations

There was no separate ‘gold standard’ by which to judge the accuracy of the final endpoints committee adjudications, and useful death certificates could not be obtained on about a third of PIVOT participants who died.

Conclusions

The low level of initial agreement on cause of death among endpoint committee members and the potential for biased determinations due to partial unblinding to treatment assignment raise methodologic concerns about using prostate cancer mortality as an endpoint in clinical trials like PIVOT.

Radical prostatectomy versus observation for localized prostate cancer

BACKGROUND

The effectiveness of surgery versus observation for men with localized prostate cancer detected by means of prostate-specific antigen (PSA) testing is not known.

METHODS

From November 1994 through January 2002, we randomly assigned 731 men with localized prostate cancer (mean age, 67 years; median PSA value, 7.8 ng per milliliter) to radical prostatectomy or observation and followed them through January 2010. The primary outcome was all-cause mortality; the secondary outcome was prostate-cancer mortality.

RESULTS

During the median follow-up of 10.0 years, 171 of 364 men (47.0%) assigned to radical prostatectomy died, as compared with 183 of 367 (49.9%) assigned to observation (hazard ratio, 0.88; 95% confidence interval [CI], 0.71 to 1.08; P=0.22; absolute risk reduction, 2.9 percentage points). Among men assigned to radical prostatectomy, 21 (5.8%) died from prostate cancer or treatment, as compared with 31 men (8.4%) assigned to observation (hazard ratio, 0.63; 95% CI, 0.36 to 1.09; P=0.09; absolute risk reduction, 2.6 percentage points). The effect of treatment on all-cause and prostate-cancer mortality did not differ according to age, race, coexisting conditions, self-reported performance status, or histologic features of the tumor. Radical prostatectomy was associated with reduced all-cause mortality among men with a PSA value greater than 10 ng per milliliter (P=0.04 for interaction) and possibly among those with intermediate-risk or high-risk tumors (P=0.07 for interaction). Adverse events within 30 days after surgery occurred in 21.4% of men, including one death.

CONCLUSIONS

Among men with localized prostate cancer detected during the early era of PSA testing, radical prostatectomy did not significantly reduce all-cause or prostate-cancer mortality, as compared with observation, through at least 12 years of follow-up. Absolute differences were less than 3 percentage points. (Funded by the Department of Veterans Affairs Cooperative Studies Program and others; PIVOT ClinicalTrials.gov number, NCT00007644.).

The relationship of the intensity of posttreatment prostate-specific antigen surveillance and prostate cancer outcomes: results from a population-based cohort

OBJECTIVE

To determine whether higher intensity of prostate-specific antigen (PSA) surveillance was associated with earlier detection of biochemical recurrence (BCR) or survival.

PATIENTS AND METHODS

We identified a population-based cohort of 832 men diagnosed with nonmetastatic prostate cancer between January 1, 1995, and July 31, 2006. These men were treated with radical prostatectomy (RP), brachytherapy or external beam radiation therapy (RT), or primary androgen deprivation therapy or chose watchful waiting. To test the associations of intensity in PSA surveillance with study outcomes, we used a 2-year landmark analysis to assess whether the number of PSA tests during the first 2 years after treatment was associated with earlier detection of BCR, prostate cancer-related mortality, and all-cause mortality. We used landmark analysis to assess the association of PSA intensity, adjusting for clinicopathologic covariate, with outcome.

RESULTS

Median follow-up time for the entire cohort was 6.7 years. Higher Gleason score was the only clinicopathologic variable associated with higher PSA frequency in multivariable analysis for both the RP and RT groups (P value of .001 and .05, respectively). After adjustment for other covariates, the frequency of PSA tests during the first 2 years after RP did not increase the ability to detect BCR (hazard ratio, 1.00; 95% confidence interval, 0.84-1.19) or all-cause mortality (hazard ratio, 0.95; 95% confidence interval, 0.70-1.30) in the landmark analysis.

CONCLUSION

Higher intensity of PSA surveillance during the 2 years after RP or RT did not improve earlier detection of BCR or survival. Evidence-based guidelines for PSA surveillance after primary treatment are needed.

Comprehensive quality-of-life outcomes in the setting of a multidisciplinary, equal access prostate cancer clinic

OBJECTIVES

To identify racial and demographic factors that influence treatment choice and its resulting impact on health-related quality of life (HRQoL) for prostate cancer patients.

METHODS

Patients presenting to an equal access, military, multidisciplinary prostate cancer clinic composed the study group. The Expanded Prostate Cancer Index Composite (EPIC), EPIC Demographic, and Medical Outcomes Study Short Form 36 were the instruments used. Evaluation was performed before treatment and every 3 months after treatment.

RESULTS

The study group comprised 665 patients. Caucasians were 3-fold more likely to choose surgery (radical prostatectomy [RP]) over external beam radiation therapy (EBRT). Patients who earned more than $100,000 annually disproportionately chose RP (P < .0001). Similarly, those having a graduate school degree disproportionally chose RP (P < .0001). Patients undergoing RP had the greatest risk of urinary function decline (P < .0001) and sexual bother (P = .0003). African Americans (AA) had a greater risk of urinary function decline irrespective of treatment choice. Patients undergoing EBRT had equivalent urinary function to expectant management (EM) at 12 months (P < .0001). Brachytherapy was the only treatment that posed an increased risk of urinary bother decline when compared with EM (P = .0217). EBRT alone did not show significant decrement in sexual function when compared with EM.

CONCLUSIONS

RP was chosen by patients of Caucasian ethnicity and patients with higher income and education level, despite providing the greatest risk of HRQoL decline. EBRT had no significant impact on urinary function, sexual function, or sexual bother scores at 12 months. EBRT may be offered to older patients with minimal HRQoL impact. Pretreatment counseling of HRQoL outcomes is essential to overall prostate cancer management.

Reporting of Time-to-Event End Points and Tracking of Failures in Randomized Trials of Radiotherapy With or Without Any Concomitant Anticancer Agent for Locally Advanced Head and Neck Cancer

Purpose

For multiple reasons, including complexities in anatomy and management, locally advanced squamous cell carcinomas of the head and neck (SCCHNs) represent a challenging disease for the reporting of end points and the tracking of failures.

Methods

We retrieved all randomized trials published in English that began accrual on or after 1978 and enrolled previously untreated patients with nonmetastatic SCCHN receiving primary radiotherapy with or without any concomitant anticancer agent. The reporting of time-to-event end points and the tracking of failures in these trials were analyzed. Failures were defined as events meeting a prespecified end point definition.

Results

Forty trials involving a total of 125 time-to-event end points were identified. A total of 17 different types of end points were reported. Locoregional control and overall survival accounted for 70% of primary end points. Except for survival, the definitions used for all other end points were heterogeneous. Among 72 end points tracking locoregional failures, 29% did not define the term, whereas 64% specified the absence of complete response as a failure. Overall, the specification of details related to elective neck dissection or salvage surgery to define locoregional failures was deficient. Furthermore, it was rarely stated whether residual disease found during these procedures represents a failure. The methods and timing specifications to assess failures were frequently missing in published reports. The tracking of other types of failure beyond the first failure was reported in only one trial.

Conclusion

These results support the need to standardize the selection, definition, and reporting of time-to-event end points in clinical trials of locally advanced SCCHN.

Quality of life findings from a multicenter, multinational, observational study of patients with metastatic hormone-refractory prostate cancer

BACKGROUND

The assessment of health-related quality of life (HRQL) for patients with hormone-refractory prostate cancer (HRPC) is of paramount importance because new treatments have a modest impact on survival but side effects of treatment and disease symptoms can significantly impact HRQL.

METHODS

This was an observational, non-interventional, multi-center, multi-national cohort study of patients with metastatic HRPC. Health-related quality of life was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ C30), the Functional Assessment of Cancer Therapy-Prostate (FACT-P) and the EQ-5D index. Mean changes from baseline to month 3, 6, and 9 were computed and tested using paired t-tests.

RESULTS

FACT-P PCS, EQ-5D index and 10 of 14 EORTC domains were statistically significantly lower (P < 0.05) than the baseline scores at the 3, 6 and 9 month visits. The domains that did not reach statistical significance were cognitive functioning, insomnia, diarrhea and financial difficulties.

CONCLUSIONS

These data demonstrate that patients with metastatic HRPC experience rapid, significant deterioration in HRQL, highlighting the need for effective palliative therapy for men with HRPC.

Quality of life as a potential predictor for morbidity and mortality in patients with metastatic hormone-refractory prostate cancer

BACKGROUND

The association between HRQL measures with outcomes in patients with metastatic hormone-refractory prostate cancer (HRPC) is unclear.

METHODS

Baseline and 12-week HRQL was collected using the European Organization for Research and Treatment of Cancer (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy - Prostate (FACT-P). Outcomes included: (1) survival; (2) time to disease progression and (3) time to bone pain. Cox proportional hazards regression models were used. The relative predictive performance of each HRQL instrument and domain was compared.

RESULTS

Baseline HRQL scores and 12-week change scores > the median were significant predictors of all clinical outcomes but varied by domain. For example, the hazard of death for a change in FACT-P Grand Total Score > median was 49% of the hazard for a change < or = the median. Including baseline or 12-week change in HRQL resulted in improvement in prediction performance.

CONCLUSIONS

Patients with better baseline HRQL have better predicted survival, time to disease progression and pain prognosis than those with worse HRQL. In addition, the 12-week change in HRQL appears to improve predictive accuracy for most clinical outcomes. It appears that greater deterioration in HRQL is prognostic for rapid disease progression.

Multimodal treatment strategies combining neoadjuvant hormonal therapy and/or chemotherapy with radical prostatectomy in high-risk localised prostate cancer

By combining the readily available clinical parameters of tumour stage, Gleason score of the diagnostic biopsy specimen and serum prostate-specific antigen level, men with newly diagnosed prostate cancer can be assessed as to their risk of treatment failure after radiotherapy or radical prostatectomy. For men considered to be at high-risk of treatment failure after local therapy alone, multimodal treatment strategies may result in improved cancer-control outcomes. This strategy has proven effective in the setting of clinical stage T3 - T4 tumours in which the combination of radiotherapy followed by hormonal therapy has improved patient survival. The benefit of neoadjuvant or adjuvant hormonal and/or chemotherapy followed by radical prostatectomy in this setting is unclear but is the subject of ongoing or planned Phase III clinical trials. These studies will help examine the role of multimodal treatment strategies in these high-risk patients.

Beyond the development of health-related quality-of-life (HRQOL) measures: a checklist for evaluating HRQOL outcomes in cancer clinical trials--does HRQOL evaluation in prostate cancer research inform clinical decision making?

PURPOSE

The aim of this study was to evaluate whether the inclusion of health-related quality of life (HRQOL), as a part of the trial design in a randomized controlled trial (RCT) setting, has supported clinical decision making for the planning of future medical treatments in prostate cancer.

MATERIALS AND METHODS

A minimum standard checklist for evaluating HRQOL outcomes in cancer clinical trials was devised to assess the quality of the HRQOL reporting and to classify the studies on the grounds of their robustness. It comprises 11 key HRQOL issues grouped into four broader sections: conceptual, measurement, methodology, and interpretation. Relevant studies were identified in a number of databases, including MEDLINE and the Cochrane Controlled Trials Register. Both their HRQOL and traditional clinical reported outcomes were systematically analyzed to evaluate their consistency and their relevance for supporting clinical decision making.

RESULTS

Although 54% of the identified studies did not show any differences in traditional clinical end points between treatment arms and 17% showed a difference in overall survival, 74% of the studies showed some difference in terms of HRQOL outcomes. One third of the RCTs provided a comprehensive picture of the whole treatment including HRQOL outcomes to support their conclusions.

CONCLUSION

A minimum set of criteria for assessing the reported outcomes in cancer clinical trials is necessary to make informed decisions in clinical practice. Using a checklist developed for this study, it was found that HRQOL is a valuable source of information in RCTs of treatment in metastatic prostate cancer.

Quality of life after treatment for prostate cancer

Quality of life is a major concern of patients when they are choosing treatment for prostate cancer. Health-related quality of life is a patient-centered variable from the field of health services research that can be measured in a valid and reliable manner. Using standardized questionnaires specifically developed to capture health-related quality of life data in men with prostate cancer, the effect of treatments on patients' quality of life can be studied. Patients with localized disease who are undergoing radical prostatectomy tend to have more sexual and urinary dysfunction than men undergoing external beam radiation therapy, although both groups have more impairment in these areas than age-matched controls. Men undergoing external beam radiation therapy have worse bowel function and more urinary distress from irritative voiding symptoms than men undergoing radical prostatectomy or age-matched controls. Recent studies of men undergoing interstitial brachytherapy indicate that these patients have less urinary leakage than those who undergo radical prostatectomy, but experience considerably more irritating voiding symptoms, which often profoundly affect their quality of life. Better information regarding the potential impact of prostate cancer treatment on quality of life will improve medical decision-making.

Markers and meaning of primary treatment failure

BCR is the most clinically used endpoint for identification of treatment failure. Approximately 15% to 53% of patients undergoing primary curative therapy will develop BCR. BCR often precedes clinically detectable recurrence by years. It does not necessarily translate directly into PCa morbidity and mortality, nor does it always reflect the desired endpoint. Furthermore, it has not been validated as a surrogate endpoint, in that interventions that have been shown to alter the PSA level have not been shown to also alter survival. The utility of PSA level as a surrogate endpoint is brought into question by the knowledge that the overall survival rate of patients at 10 years is similar in patients with and without BCR, and that in a significant proportion of men, the only evidence of disease during their lifetime will be a detectable PSA level. The likelihood of developing BCR post-therapy can be predicted by using multiple clinical and pathologic variables. With the development of nomograms that incorporate several markers, the accuracy of prediction has improved. Until recently, the natural history of BCR post-RRP has not been well understood. Pound et al showed the heterogenous and prolonged natural history of BCR. In this large series of men with BCR following RRP, only 34% of men developed metastatic disease. The median time from development of BCR to identification of metastases was 8 years, and the median time from the development of metastatic disease to death was just under 5 years. These data highlight the extremely variable and potentially indolent nature of BCR. The risk of metastatic disease following BCR has been relatively well defined and relates to PSADT and time to PSA recurrence. It generally is accepted that a PSADT of less than 6 to 10 months and a time to PSA recurrence of less than 1 to 2 years relates to a higher risk of developing metastatic disease. Local recurrence, however, remains poorly understood with respect to its true incidence, clinical significance, and natural history. The significance of BCR post-RT remains unclear due to the lack of data on its natural history. Attempts have been made to identify patients at high risk for metastatic progression by looking at time to PSA recurrence and PSADT. A PSADT of less than 6 to 12 months and a time to PSA recurrence of less than 12 months reflects a higher risk of developing metastatic disease. Accurate risk stratification by means of an algorithm similar to that produced by Pound et al has not been performed on a large cohort, thus making risk assessment for an individual patient difficult. The major dilemma for clinicians in the management of BCR is the identification of the site of disease recurrence, which ultimately guides therapy decisions. Clinicopathologic features allow for risk stratification for recurrence, and multiple investigations have attempted to localize the site of recurrence. Time to biochemical progression, Gleason score, and PSADT are predictive of the probability and time to development of metastatic disease, and allow for stratification of patients into different risk groups (see Table 2). TRUS, CT, PET, and DRE all have limited utility in the identification of local recurrence. ProstaScint and MRI have demonstrated encouraging initial results: however, they require further investigation. Bone scintigraphy is of little value for the initial investigation of BCR. In patients with a PSA level of less than 10 ng/mL, the risk of having a positive bone scan is less than 1% and, until the PSA level rises above 40 ng/mL, the risk of having a positive bone scan is less than 5%. Therefore, bone scintigraphy should be reserved for patients with a PSA level greater than 10 to 20 ng/mL or patients with a rapidly rising PSA level. Using new MRI sequences, there is some evidence that MRI is better for the detection of bony metastatic disease; however, this technique requires further investigation. BCR causes anxiety for the patient and the treating doctor, because the best way to manage patients with PSA-only progression is unknown. Currently, there are no validated treatment recommendations for the management of BCR. The information in this review provides the framework for assignment of patients into clinical trials based on different risk categories. Patients at high risk for metastatic progression could be identified early and thus entered into appropriate clinical trials for systemic therapies. Similarly, patients with a low risk of progression could be placed into observation protocols, potentially sparing them from exhaustive and inappropriate investigations.

Health related quality of life in prostate carcinoma patients: a systematic review of randomized controlled trials

BACKGROUND

Health related quality of life (HRQOL) is increasingly reported as an important endpoint in cancer clinical trials. However, evidence suggests that HRQOL reporting is often inadequate. Given this, the authors undertook a systematic review to evaluate HRQOL assessment methodology and reported outcomes of randomized controlled clinical trials (RCTs) with prostate carcinoma patients.

METHODS

A comprehensive search of the literature from 1980 to 2001, mainly on the following databases, was undertaken: MedLine, Cancerlit, and the Cochrane Controlled Trials Register. Studies were identified according to a predefined coding scheme, including HRQOL measure, cultural validity, compliance data reported and the clinical significance of the results.

RESULTS

Twenty-five RCTs were identified, involving 8015 patients primarily with metastatic cancer. Bicalutamide was the medical treatment against which most treatment comparisons were made. Limitations identified included the fact that only 44% of the studies gave a rationale for selecting a specific HRQOL measure, 64% of the studies failed to report information about the administration of the HRQOL measure, and 56% failed to report compliance at baseline. The measure most often used was the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Care 30 (EORTC QLQ-C30), although some studies used non-validated HRQOL tools.

CONCLUSIONS

The current study revealed a lack of a uniform approach to HRQOL assessment and several methodologic limitations. It is possible that such methodologic limitations have influenced trial findings for HRQOL outcomes.

A randomized trial comparing radical prostatectomy with watchful waiting in early prostate cancer

BACKGROUND

Radical prostatectomy is widely used in the treatment of early prostate cancer. The possible survival benefit of this treatment, however, is unclear. We conducted a randomized trial to address this question.

METHODS

From October 1989 through February 1999, 695 men with newly diagnosed prostate cancer in International Union against Cancer clinical stage T1b, T1c, or T2 were randomly assigned to watchful waiting or radical prostatectomy. We achieved complete follow-up through the year 2000 with blinded evaluation of causes of death. The primary end point was death due to prostate cancer, and the secondary end points were overall mortality, metastasis-free survival, and local progression.

RESULTS

During a median of 6.2 years of follow-up, 62 men in the watchful-waiting group and 53 in the radical-prostatectomy group died (P=0.31). Death due to prostate cancer occurred in 31 of 348 of those assigned to watchful waiting (8.9 percent) and in 16 of 347 of those assigned to radical prostatectomy (4.6 percent) (relative hazard, 0.50; 95 percent confidence interval, 0.27 to 0.91; P=0.02). Death due to other causes occurred in 31 of 348 men in the watchful-waiting group (8.9 percent) and in 37 of 347 men in the radical-prostatectomy group (10.6 percent). The men assigned to surgery had a lower relative risk of distant metastases than the men assigned to watchful waiting (relative hazard, 0.63; 95 percent confidence interval, 0.41 to 0.96).

CONCLUSIONS

In this randomized trial, radical prostatectomy significantly reduced disease-specific mortality, but there was no significant difference between surgery and watchful waiting in terms of overall survival.

Pathologic evidence of dose-response and dose-volume relationships for prostate cancer treated with combined external beam radiotherapy and high-dose-rate brachytherapy

PURPOSE

The clinical significance of postradiotherapy (RT) prostate biopsy characteristics is not well understood relative to the known prognostic factors. We performed a detailed pathologic review of posttreatment biopsy specimens in an attempt to clarify their relationship with clinical outcome and radiation dose.

METHODS AND MATERIALS

Between 1991 and 1998, 78 patients with locally advanced prostate cancer were prospectively treated with external beam RT in combination with high-dose-rate brachytherapy at William Beaumont Hospital and had post-RT biopsy material available for a complete pathologic review. Patients with any of the following characteristics were eligible for study entry: pretreatment prostate-specific antigen level > or =10.0 ng/mL, Gleason score > or =7, or clinical Stage T2b-T3cN0M0. Pelvic external beam RT (46.0 Gy) was supplemented with three (1991-1995) or two (1995-1998) ultrasound-guided transperineal interstitial (192)Ir high-dose-rate implants. The brachytherapy dose was escalated from 5.50 to 10.50 Gy per implant. Post-RT prostate biopsies were performed per protocol at a median interval of 1.5 years after RT. All pre- and post-RT biopsy specimen slides from each case were reviewed by a single pathologist (N.S.G.). The presence and amount of residual cancer, most common RT-effect score, and least amount RT-effect score were analyzed. The median follow-up was 5.7 years. Biochemical failure was defined as three consecutive prostate-specific antigen rises.

RESULTS

Forty patients (51%) had residual cancer in the post-RT biopsies. The 7-year biochemical control rate was 79% for patients with negative biopsies vs. 62% for those with positive biopsies with marked RT damage vs. 33% for those with positive biopsies with no or minimal RT damage. A greater percentage of positive pre-RT biopsy cores (p = 0.01), lower total RT dose (p = 0.001), lower dose per implant (p = 0.001), and greater percentage of positive post-RT biopsy cores (p = 0.01) were each associated with biochemical failure (Cox regression, univariate analysis). For patients with <25% positive post-RT biopsy cores, the 7-year biochemical control rate was 81% vs. a 62% biochemical control rate for those with 25-49% positive cores and only 32% for those with > or =50% positive cores (p = 0.01). On Cox multiple regression analysis, only the percentage of positive pre-RT biopsy cores and RT dose remained significantly associated with biochemical failure. Of all the factors analyzed, only the pretreatment cancer volume and lower RT dose were significantly associated with residual cancer and/or residual cancer with no or minimal RT damage. A greater percentage of positive pre-RT biopsy cores was associated with both a positive post-RT biopsy (p = 0.08) and a greater percentage of positive post-RT biopsy cores (p = 0.04). A lower total RT dose was associated with both a positive post-RT biopsy (p = 0.08) and a greater percentage of positive post-RT biopsy cores (p = 0.02). For patients who received <80 Gy (equivalent in 2-Gy fractions), 73% had positive post-RT biopsies vs. a 56% biopsy positivity rate for those who received 84-90 Gy and only 39% for those who received > or =92 Gy (p = 0.07).

CONCLUSION

Patients with positive post-RT biopsies are more likely to experience biochemical failure, especially when the RT damage is minimal. Patients who have a larger pretreatment tumor volume or receive a lower RT dose are more likely to demonstrate post-RT biopsy positivity and biochemical failure.

Risk of prostate carcinoma death in patients with lymph node metastasis

BACKGROUND

The presence of lymph node metastasis is a poor prognostic sign for patients with prostate carcinoma. Results of published reports on survival among patients with lymph node metastasis are difficult to assess because of treatment selections. The extent to which lymph node status will have an impact on a patient's survival is uncertain.

METHODS

The authors analyzed 3463 consecutive Mayo Clinic patients who underwent radical prostatectomy and bilateral pelvic lymphadenectomy for prostate carcinoma between 1987 and 1993. Of these patients, 322 had lymph node metastasis at the time of surgery, and 297 lymph node positive patients also received adjuvant hormonal therapy within 90 days of surgery. The progression free rate and the cancer specific survival rate were used as outcome endpoints in univariate and multivariate Cox proportional hazards models. The median follow-up was 6.3 years. Progression was defined by elevation of serum prostate specific antigen (PSA) > or = 0.4 ng/mL after surgery, development of local recurrence, or distant metastasis documented by biopsy or radiographic examination.

RESULTS

The 5-year and 10-year progression free survival rates (+/- standard error [SE]) for patients with lymph node metastasis were 74% +/- 2% and 64% +/- 3%, respectively, compared with 77% +/- 1% and 59% +/- 2%, respectively, for patients without lymph node metastasis. The 5-year and 10-year cancer specific survival rates were 94% +/- 1% and 83% +/- 4%, respectively, compared with 99% +/- 0.1% and 97% +/- 0.5%, respectively, for patients without lymph node metastasis. Among patients with a single lymph node metastasis, the 5-year and 10-year cancer specific survival rates were 99% +/- 1% and 94% +/- 3%, respectively. After adjustment for extraprostatic extension, seminal vesicle invasion, Gleason grade, surgical margins, DNA ploidy, preoperative serum PSA concentration, and adjuvant therapy, the hazard ratio for death from prostate carcinoma among patients with a single lymph node metastasis compared with patients who were without lymph node metastasis was 1.5 (95% confidence interval, 0.5-5.0; P = 0.478), whereas the hazard ratio for death from prostate carcinoma was 6.1 (95% confidence interval, 1.9-19.6; P = 0.002) for those with two positive lymph nodes and 4.3 (95% confidence interval, 1.4-13.0; P = 0.009) for those with three or more positive lymph nodes. There was no significant difference in the progression free survival rate among patients with or without lymph node metastasis in multivariate analysis after controlling for all relevant variables, including treatments (hazard ratio,1.0; 95% CI, 0.7-1.3; P = 0.90).

CONCLUSIONS

Patients with prostate carcinoma who have multiple regional lymph node metastases had increased risk of death from disease, whereas patients with single lymph node involvement appeared to have a more favorable prognosis after radical prostatectomy and immediate adjuvant hormonal therapy. Excellent local disease control was achieved by using combined surgery and adjuvant hormonal therapy in patients with positive lymph nodes.

The correlation of serial prostate specific antigen measurements with clinical outcome after external beam radiation therapy of patients for prostate carcinoma

BACKGROUND

The authors analyzed retrospectively their institution's experience in treating patients with localized prostate carcinoma with external beam radiation therapy (EBRT) to determine the correlation of various biochemical failure (BF) definitions with clinical failure and cause specific survival (CSS).

METHODS

Between January 1987 and December 1997, 1,094 patients with clinical T1-T3N0M0 prostate carcinoma were treated with definitive EBRT alone at William Beaumont Hospital, Royal Oak, Michigan. All patients received EBRT alone (no adjuvant hormones) to a median total prostate dose of 66.6 grays (Gy) (range, 59.4-70.4 Gy). Multiple BF definitions were tested for their correlation with clinical failure and cause specific death (CSD = 1-CSS). All BF definitions were tested for sensitivity, specificity, and accuracy of predicting subsequent clinical failure and CSD. Positive and negative predictive values were calculated in the form of 10-year actuarial clinical failure and CSD rates. Analyses were performed on all 1,094 patients as well as for those 727 patients who had at least 5 post-RT prostate specific antigen (PSA) level measurements and who did not receive hormonal therapy for post-RT PSA elevations. The median PSA follow-up was 4.0 years for the entire population and 4.5 years for those 727 patients included in the second analysis.

RESULTS

In the entire population, 167 patients (15%) experienced clinical failure corresponding to 5- and 10-year actuarial rates of 16% and 34%, respectively. The correlation of various BF definitions with outcome was calculated in those 727 patients who did not receive hormonal therapy. For these patients, BF (as defined by the American Society for Therapeutic Radiology and Oncology Consensus Panel) yielded a 73% sensitivity, 76% specificity, and 75% overall accuracy for predicting clinical failure and a 74% sensitivity, 69% specificity, and 69% overall accuracy for predicting CSD. The 10-year clinical failure rate for those 251 patients demonstrating 3 consecutive PSA rises (BF) was 64% versus 14% for those patients who did not meet these criteria (biochemically controlled [BC]). As expected, definitions requiring only two rises were more sensitive but less specific in predicting clinical failure than those definitions requiring three or four rises. Because there were dramatically more clinically controlled patients (85%) than clinical failures (15%), the overall accuracy for each definition more closely approximated its specificity. The definitions classifying BF as a postnadir increase of > or = 3 or > or = 4 ng/mL above the nadir yielded the highest accuracies of 87% and 88%, respectively. In addition, these definitions also appeared to provide the greatest separation in clinical failure rates between BC and BF patients, an absolute difference of 77% and 76%, respectively.

CONCLUSIONS

The correlation between BF and clinical failure and CSD varies markedly depending on the BF definition used. Definitions incorporating a fixed baseline (the nadir level) and the postnadir PSA profile may have better correlation with clinical failure than definitions using the nadir only or a specific number of consecutive rises in which a variable baseline "resets" after a PSA decrease.

Quality of life following prostate cancer treatments

Quality of life is of major concern to patients when choosing a treatment for prostate cancer. Health-related quality of life (HRQOL) is a patient-centered variable from the field of health services research that can be assessed in a valid and reliable manner. Using standardized questionnaires specifically designed to measure HRQOL in men with prostate cancer, we can now study the effect of various treatments on patients' quality of life. Treatments for metastatic prostate cancer can have significant effects in all areas of patients' quality of life. Patients with localized disease undergoing radical prostatectomy (RP) tend to have more sexual and urinary dysfunction than do men undergoing external beam radiation therapy (EBRT), although both groups have worse quality of life in these areas than age-matched controls. Men undergoing EBRT have worse bowel function than age-matched controls or men undergoing RP. Recent studies of men undergoing interstitial brachytherapy indicate that these patients have less urinary leakage than those who undergo RP, but experience considerably more irritative voiding symptoms, which can profoundly affect quality of life. Patients need to be informed of the possible impact of therapy on quality of life when choosing treatment.

Report on the quality of life analysis from the phase III trial of pion versus photon radiotherapy in locally advanced prostate cancer

This report examines the quality of life (QOL) of 215 patients entered into a randomised trial between pion and photon radiotherapy for prostate cancer at a single institution. The survival and local control results of the trial were equivalent in both arms. A modification of the Rotterdam Symptom Checklist (RSCL) was used to assess QOL. Global QOL, toxicity and physical scores were found to be worse in pion-treated patients at the end of treatment (P<0.001, P<0.001, and P=0.02 respectively). There are no long-term differences in the QOL of pion- versus photon-treated patients. Sexual function was a concern for patients even at baseline. There was a progressive loss of sexual interest and erectile function. There was a significant impact from hormonal therapy at relapse. Hormonal treatment produced a stepwise significant worsening in global QOL, particularly for physical and psychological domains.

Future prospects in prostate cancer

BACKGROUND

Prostate cancer has displayed an increase in incidence unparalleled by any other tumor in the last two decades, with a steady, more gradual increase in mortality rate. Current curative strategies are focused on the detection and treatment of early-stage (T1-2 N0 M0), clinically significant tumors.

METHODS

To this aim, refinement of surgical approaches, with appropriate adjuvant therapies, will ensure more complete cancer control, while minimizing associated morbidity. New delivery systems for radiotherapy, as well as other energy sources, are evolving, while a number of promising pharmacological agents, including angiogenesis inhibitors and drugs which alter signal transduction pathways, are currently under investigation. Early detection is also being facilitated by a more widespread implementation of screening programs. Advances in tumor markers, and imaging and biopsy techniques, will allow more accurate preoperative staging. These, coupled with improvements in prognostic markers, aid the physician and patient alike in deciding on the suitability of treatment options with better estimation of outcome. Perhaps the most exciting developments in prostate cancer will come from knowledge of the molecular mechanisms underlying carcinogenesis. The potential for the development of diagnostic and therapeutic tools is immense. The efficacy of treatment can be studied at a molecular level, and strategies for preventing or slowing the development of malignancy can be formulated. RESULTS AND CONCLUSIONS Application of this knowledge in the form of gene and cellular therapy and in the development of novel systemic agents is beginning to enter the realm of clinical practice, and it may be in this field that means for cure and prevention of prostate cancer will eventually be found.

Changes in quality of life following treatment for early prostate cancer

OBJECTIVES

To explore the effects of urinary, bowel, and sexual symptoms following treatment for early (nonmetastatic) prostate cancer on health-related quality of life through an examination of the responsiveness of the Medical Outcomes Study Short Form Health Survey (SF-36).

METHODS

We conducted a prospective observational cohort study of 125 men with early prostate cancer who underwent either radical prostatectomy or radical, external beam radiotherapy. Patients completed questionnaires, which included assessments of urinary, bowel, and sexual symptoms and the SF-36 at the time of their clinical consultation prior to deciding on primary therapy and at 3 and 12-month follow-up.

RESULTS

Although cross-sectional analysis showed substantial associations between symptoms and the eight scales of the SF-36 12 months after the initiation of treatment, longitudinal analyses of changes in these scales showed only modest effects. Three scales registered changes associated with the development of new symptoms: General Health Perceptions, Vitality, and Social Function. Role Performance with Emotional Limitations demonstrated a surprising response: slight improvements in men with new symptoms, compared with substantial gains in men who survived treatment without developing new urinary, bowel, or sexual symptoms. Overall, the SF-36 demonstrated a pattern of decline at 3 months and recovery to baseline at 12 months. Rather than registering declines in response to increasing symptoms, negative changes occurred primarily in men who presented symptoms prior to treatment and whose symptoms were unchanged 12 months later.

CONCLUSIONS

The SF-36 is associated with the presence of physical symptoms but demonstrates a complicated pattern of change following treatment and the development of new urinary, bowel, and sexual problems. Multidimensional approaches to the outcomes of treatment for early prostate cancer help to clarify the magnitude of both gains and losses in quality of life.

Prostate-specific antigen after radiation therapy. Prognosis by pretreatment level and post-treatment nadir

After external beam radiation therapy, pretreatment prostate-specific antigen (PSA) is the most powerful predictor of outcome as measured PSA (biochemical) failure. The post-treatment nadir levels of PSA that predict best for subsequent freedom from PSA failure are debatable, and many nadir levels have been proposed as targets. Although lower nadirs generally are associated with superior outcomes, the identification of a single absolute nadir level was not selected at a recent ASTRO consensus conference. Rather, three consecutive PSA rises above the nadir, with date of failure at the midpoint between the nadir and first rise, were selected as a more useful end point for treatment failure.