Trends in prostate cancer incidence and mortality: an analysis of mortality change by screening intensity

BACKGROUND

The rate of death from prostate cancer has recently declined in many areas of the world. Over the past 15 years prostate-specific antigen (PSA) screening has increased in popularity, which has resulted in increases in the incidence of prostate cancer. Over the same period there have been changes in the management of the disease and, in particular, the use of androgen ablation. We set out to examine the relation between changes in prostate cancer incidence (a surrogate for PSA screening) and subsequent changes in mortality in regions using common treatment recommendations.

METHODS

We used data from prostate cancer cases and deaths reported to the British Columbia Cancer Registry during 1985-1999 to examine trends in incidence and mortality in 88 small health areas (SHAs) among men aged 50-74 years. We conducted 2 analyses. In the first we classified the SHAs by intensity of PSA screening (low, medium or high) according to their ranked age-standardized incidence rate of prostate cancer in 1990-1994 and examined subsequent trends in prostate cancer mortality. In the second analysis we examined the SHA-specific relative change in prostate cancer incidence between 1985-1989 and 1990-1994 and correlated it with the relative change in mortality for cases diagnosed after 1990.

RESULTS

Between 1985-1989 and 1990-1994 the incidence of prostate cancer increased by 53.2% and 14.6% among men aged 50-74 and those 75 and over respectively. Between 1985-1989 and 1995-1999 prostate cancer mortality declined by 17.6% and 7.9% in the 2 age groups respectively. Among men aged 50-74 years SHAs with low, middle and high levels of screening had respective increases in prostate cancer incidence of 5.4%, 53.6% and 70.5% between 1985-1989 and 1990-1994. Corresponding decreases in mortality between 1985-1989 and 1995-1999 were 28.9%, 18.0% and 13.5%. Mortality declines were greatest in SHAs with low screening levels (p = 0.032). Before 1990 prostate cancer mortality was similar in the 3 screening groups (p = 0.72). Regions with the smallest increases in incidence had the largest declines in mortality.

INTERPRETATION

We found no association between the intensity of PSA screening and subsequent decreases in prostate cancer mortality.

The effect of isotope selection on the prostate-specific antigen response in patients treated with permanent prostate brachytherapy

PURPOSE

To assess the difference in prostate-specific antigen (PSA) response kinetics in patients undergoing either (125)I or (103)Pd permanent prostate brachytherapy (PPB).

METHODS AND MATERIALS

Between 1997 and 1999, 333 patients underwent PPB as monotherapy. Forty-eight patients received a (125)I implant, and 285 received a (103)Pd implant. Biochemical relapse-free survival was defined by the Kattan modification of the American Society for Therapeutic Radiology and Oncology consensus, based on three PSA increases. In addition, the time to reach a PSA threshold of <or=1.0 ng/ml was noted. Log-rank testing was performed, and multivariate analysis was used to evaluate those variables associated with biochemical freedom from recurrence.

RESULTS

With a mean 36-month follow-up, the actuarial biochemical relapse-free survival at 4 years was 86.8%. No significant difference in biochemical relapse-free survival was noted between patients treated with (125)I and (103)Pd (p=0.417). Multivariate analysis failed to identify isotope as an independent variable to predict for biochemical relapse-free survival. The mean time for patients treated with (103)Pd to reach the threshold PSA value was 10.2 weeks, whereas it was 22 weeks for (125)I (p=0.014). When the median time to reach the PSA threshold of <or=1.0 ng/ml was used to calculate the percentage of delivered dose for each isotope relative to the prescribed dose, there was no significant difference noted between (125)I (84%) and (103)Pd (94%) (p=0.86).

CONCLUSIONS

Isotope selection does not appear to influence biochemical relapse-free survival in patients treated with monotherapy PPB. There was a significant difference (p=0.014) in time to reach a PSA threshold of <or=1.0 ng/ml noted between (125)I and (103)Pd. However, the percentage of delivered dose relative to the time to reach the threshold was the same between (125)I and (103)Pd. This information is important for during patients their post-PPB period.

[Screening for prostatic cancer]

The discussion covers different aspects of application of programs of early prostatic cancer diagnosis. Arguments for and against the screening are presented. The existing methods of early prostatic cancer diagnosis are reviewed. How to improve the technique of taking prostatic biopsy is shown.

Quality of life and economic considerations in the management of prostate cancer

The purpose of this article was to provide an overview of the morbidity and mortality of prostate cancer, QOL issues and the economic impact of the disease. We searched Medline (from 1990 onwards) for all studies dealing with prostate cancer epidemiology, treatment, screening and staging, and critically reviewed the most relevant articles, focusing on pharmacoeconomic issues. Prostate cancer is the most common cancer in men. In the US, new estimated cases of prostate cancer represented 14.8% of all new cancer cases for 2000, with estimated deaths from prostate cancer comprising 5.8% of all deaths from cancer. Current options for prostate cancer management include radical prostatectomy, cryosurgery, radiotherapy, hormone therapy and watchful waiting. Many of the long-term effects of treatment, such as urinary incontinence, impotence and radiation-induced proctitis, have a large impact on patients' quality of life and, in some patients, may offset the clinical benefits. Regulatory bodies and managed care organisations are assigning increasing importance to the evaluation of QOL benefits as an independent clinical endpoint and a measure of patient satisfaction. Several screening programmes for early detection of prostate cancer, mostly based on prostate-specific antigen (PSA) measurement or digital rectal examination, have been proposed, but their routine implementation in all asymptomatic elderly men has been questioned. There is still no definite proof that patient outcomes are improved by extensive PSA screening. Furthermore, the total cost of a screening programme is difficult to define since it extends well beyond the initial test. Several instruments are used for QOL assessment in prostate cancer, some of which have been specifically developed for, or adapted to, patients with this disease, such as the Functional Assessment Cancer Therapy (FACT) tool, Prostate Cancer Treatment Outcome Questionnaire (PCTO-Q) and Prostate Cancer Specific Quality of Life Instrument (PROSQOLI). More than 50% of treatment costs for prostate cancer are accrued during the patient's last year of life, and total initial care costs decrease with increasing age. In the US, initial average inpatient costs were estimated at $US 2253, in 1995, for men aged > or =80 years, compared with $US 4540 for men aged 35-64 years. In recent years, treatments based on combined modalities (i.e. radiotherapy/prostatectomy plus hormonal therapies) have emerged. Although cost-effectiveness analyses of various treatment options have been attempted, the strength of their conclusions appears to be limited by the lack of homogeneous literature data on the effects of such interventions on survival and morbidity.

Weekly high-dose calcitriol and docetaxel in metastatic androgen-independent prostate cancer

PURPOSE

To determine the safety and efficacy of weekly high-dose oral calcitriol (Rocaltrol, Roche Pharmaceuticals, Basel, Switzerland) and docetaxel (Taxotere, Aventis Pharmaceuticals, Bridgewater, NJ) in patients with metastatic androgen-independent prostate cancer (AIPC).

PATIENTS AND METHODS

Thirty-seven patients were treated with oral calcitriol (0.5 micro g/kg) on day 1 followed by docetaxel (36 mg/m(2)) on day 2, repeated weekly for 6 weeks of an 8-week cycle. Patients maintained a reduced calcium diet and increased oral hydration. Prostate-specific antigen (PSA) response was the primary end point, which was defined as a 50% reduction in PSA level confirmed 4 weeks later.

RESULTS

Thirty of 37 patients (81%; 95% confidence interval [CI], 68% to 94%) achieved a PSA response. Twenty-two patients (59%; 95% CI, 43% to 75%) had a confirmed > 75% reduction in PSA. Eight of the 15 patients with measurable disease (53%; 95% CI, 27% to 79%) had a confirmed partial response. Median time to progression was 11.4 months (95% CI, 8.7 to 14 months), and median survival was 19.5 months (95% CI, 15.3 months to incalculable). Overall survival at 1 year was 89% (95% CI, 74% to 95%). Treatment-related toxicity was generally similar to that expected with single-agent docetaxel. Pharmacokinetics of either calcitriol or docetaxel were not affected by the presence of its companion drug in an exploratory substudy.

CONCLUSION

The combination of weekly oral high-dose calcitriol and weekly docetaxel is a well-tolerated regimen for AIPC. PSA and measurable disease response rates as well as time to progression and survival are promising when compared with contemporary phase II studies of single-agent docetaxel in AIPC. Further study of this regimen is warranted.

[Treatment strategy for locally advanced prostate cancer]

With the increasing aged population, prostate cancer has become one of the commonest malignant tumors in the United States. The incidence of prostate cancer is the highest among malignant tumors in males, and the mortality rate is the second highest following lung cancer. Even when prostate cancer is diagnosed to be in the early stage preoperatively, its excised lesions are often judged pathohistologically to be locally advanced tumor (staging error). Therefore, to estimate the exact pathological stage of excised lesions by preoperative parameters such as clinical T, PSA and biopsy Gleason Score, Partin's nomogram is generally used in the United States. However, according to the annual update version of the 2001 millennium update, radical prostatectomy should not be applied to T3, and it was excluded from the nomogram. Currently, the standard methods for the treatment of locally advanced prostate cancer may be external beam radiotherapy and brachytherapy with neoadjuvant hormonal therapy and intraprostate 125I and 103Pd seeds with neoadjuvant hormonal therapy, although the long-term results are unknown. In our study, similar to a report by Messing et al., adjuvant hormonal therapy might be effective in patients in whom the tumor was diagnosed as being in the early stage but was later found to be N (+) after its operation.

Evaluation of external beam radiotherapy and brachytherapy for localized prostate cancer using equivalent uniform dose

Various radiotherapy (RT) modalities, such as external beam radiotherapy (EBRT) and permanent/high-dose-rate (HDR) brachytherapy, have been used for the management of localized prostate cancer. Using the linear-quadratic (LQ) model, we compared the relative merits of these modalities in terms of equivalent uniform dose (EUD) and tumor control probability (TCP). The LQ parameters (alpha = 0.15 Gy(-1) and alpha/beta = 3.1 Gy) determined recently from compiled clinical data, as well as other sets of LQ parameters for prostate cancer, were used to carry out the EUD and TCP calculations. A computer code was developed for this purpose. We calculate the EUD for some common RT modalities, and present the corresponding TCP data predicted for a sample patient group (high-risk). Biological equivalence of treatment outcome among various RT modalities is demonstrated. The model suggests that the hypofractionation is preferred in terms of tumor control, due to the lower alpha/beta ratio. Also, the current combined treatment schemes (initial EBRT + permanent/HDR brachytherapy boost) provide higher EUD and TCP than these monotherapies. The study shows that EUD is less sensitive to model parameters than TCP, and EUD can be used to compare and to optimize treatment plans involving different RT modalities. Techniques to further optimize and/or to combine external beams with brachytherapy for better treatment outcomes are proposed.

[Results of a 5-year screening for prostatic cancer]

The results of 5-year screening (1996-2000) for prostatic cancer in 1129 males 40 to 80 years of age are presented. The examination included: measurement of blood levels of prostate-specific antigen (PSA), finger rectal examination, transrectal ultrasonic examination (TRUE) and, on demand, biopsy of the prostatic gland. Prostatic cancer was diagnosed in 1.5, 2.2 and 16% patients having PSA levels of 0-4.0, 4.0-10.0 and 10.0-30.0% ng/ml, respectively. At finger rectal examination prostatic cancer was suspected in 8% examinees, only in 33% of them the diagnosis was verified morphologically. By TRUE evidence 7% examinees were suspected and in 44.3% of them prostatic cancer was confirmed. Thus, biopsy proved necessary in 172 cases of 1129 examinees. In 64 (5.7%) males prostatic cancer was diagnosed and confirmed. Early prostatic cancer in the screened men and those consulted in the outpatient department of the National Cancer Research Center was detected in 77.7 and 22% men, respectively. The conclusion is made that men over 50 years of age should undergo prophylactic examination of the prostatic gland once a year.

Estimating survival benefit in castrate metastatic prostate cancer: decision making in proceeding to a definitive phase III trial

OBJECTIVES

In designing a Phase II trial, the acceptable clinical activity region for a new therapy is often developed using data from historically treated patients. This region incorrectly ignores the variability of this estimate, because the efficacy of the prior treatment lies somewhere around the estimate. The size of this interval is dependent on the sample size used. This report illustrates the use of a published method that accounts for this uncertainty and aids in the decision to proceed to a definitive trial.

METHODS

A historical data set of low-risk patients with progressive castrate metastatic prostate cancer and a group of similar patients treated in a Phase II chemotherapy trial were used. The 1-year Kaplan-Meier estimate of survival was obtained for both. This approach uses the 75% upper confidence bound of the 1-year survival probability from the historical data set to define the lower limit of acceptable clinical activity. Use of this bound makes the approach more conservative, and hence the decision to proceed to a Phase III trial more difficult.

RESULTS

In the low-risk historical patients, the 1-year Kaplan-Meier estimate of survival was 66.4% (75% upper confidence bound 71.0%). In the Phase II patients, the 1-year Kaplan-Meier estimate of survival was 89.5% (95% lower confidence bound 78.2%).

CONCLUSIONS

A hypothesis test using the 75% upper confidence bound to define the lower limit of acceptable clinical activity demonstrates that the 1-year survival probability on Taxol/estramustine/carboplatin is greater than that of the historical population, and hence should be taken into a definitive trial. The design provides investigators increased confidence in making this decision.

Clinical utility of endorectal MRI in determining PSA outcome for patients with biopsy Gleason score 7, PSA <or=10, and clinically localized prostate cancer

PURPOSE

Although the optimal management for patients with high-grade clinically localized prostate cancer is undefined, radical prostatectomy (RP) or external beam radiotherapy (EBRT) is performed. The clinical utility of the pretreatment prostrate-specific antigen (PSA) level (<or=10 and >10 ng/mL) and endorectal MRI (erMRI) stage (T3 vs. T2) to stratify PSA outcome after RP in these patients was evaluated.

METHODS AND MATERIALS

erMRI was performed in 147 men with biopsy Gleason score >or=7 and 1992 AJCC clinical Stage T1c or T2a disease before RP. Enumerations of the biopsy and prostatectomy Gleason scores, pathologic stage, and margin status were performed for each pretreatment group on the basis of erMRI findings and PSA level. Comparisons were made using a chi-square metric. The median follow-up was 4.5 years (range 1-10 years). Comparisons of the actuarial freedom from PSA failure (bNED) were made using the log-rank test.

RESULTS

erMRI Stage T2 and T3 disease was found in 132 and 15 patients, respectively. On stratification by PSA level, patients with erMRI T3 disease had similar bNED outcomes (p = 0.46), regardless of the PSA level. The 3-year bNED rate was 82%, 64%, and 25% (p <0.0001) for Group 1 (erMRI T2 and PSA <or=10 ng/mL), Group 2 (erMRI T2 and PSA >10 ng/mL), and Group 3 (erMRI T3 with any PSA level), respectively. The rates of prostatectomy T3 disease, biopsy and prostatectomy Gleason score 8-10, and positive surgical margins were significantly higher (p <or=0.007) in Group 3, followed by Group 2 and were lowest in Group 1. When considering only the patients with biopsy Gleason score 7 (n = 110), the 3-year bNED rate was 83%, 63%, and 28% (p trend <0.0001) for Groups 1, 2, and 3, respectivel.

CONCLUSION

In the setting of biopsy Gleason score >or=7, PSA <or=10 ng/mL, and clinically localized disease, local therapy alone may be adequate for patients with erMRI T2 disease. On the other hand, these data suggest that more aggressive therapy may be warranted in patients with erMRI T3 disease. Given the survival benefit established for patients with locally advanced prostate cancer treated with EBRT and androgen suppression therapy compared with EBRT alone, erMRI staging may help identify patients with high biopsy Gleason score and clinically localized disease who may benefit most from treatment with EBRT and hormonal therapy as opposed to EBRT alone.

Race and survival of men treated for prostate cancer on radiation therapy oncology group phase III randomized trials

PURPOSE

We assessed the impact of race on survival in men treated with external beam radiotherapy with or without hormonal therapy for localized prostate cancer in Radiation Therapy Oncology Group randomized trials.

MATERIALS AND METHODS

Between 1975 and 1992, 2,048 men were treated for clinically localized prostate cancer in 1 of 4 consecutive prospective phase III randomized trials. After excluding nonblack and nonwhite men 2,012 remained for analysis. Patients were included in this analysis if they were deemed evaluable and eligible for the trial, and followup information and centrally reviewed pathological results were available. Short-term hormonal therapy consisted of goserelin acetate and flutamide administered 2 months before and during radiotherapy. Long-term hormonal therapy consisted of adjuvant goserelin acetate, which was generally given for 2 years or more. Pretreatment prostate specific antigen (PSA) findings were available in 430 cases (21%), including 213 treated with radiotherapy alone, 60 treated with short-term hormonal therapy and 157 on long-term hormonal therapy. Mean pretreatment PSA was 68.8 and 35.2 ng./ml. in black and white patients, respectively. Cox proportional hazards models were used to identify the impact of previously defined risk groups on overall and disease specific survival. Multivariate analysis was done for the significance of race using a stratified Cox model. Median followup in patients treated in early and late studies exceeded 11 and 6 years, respectively.

RESULTS

On univariate analysis black race was associated with lower overall and disease specific survival (p = 0.04, RR = 1.24 and p = 0.016, RR = 1.41, respectively). After adjusting for risk group and treatment type (with or without short-term or long-term hormonal therapy) race was no longer associated with outcome (p >0.05). The trend for a persistent difference in survival was likely due to the higher tumor burden in black men, as reflected in higher PSA.

CONCLUSIONS

As previously reported, tumor grade (Gleason score), palpation T stage, lymph node status, pretreatment PSA and treatment type are major predictors of overall and disease specific survival. We noted no evidence that race has independent prognostic significance in patients treated for prostate cancer in Radiation Therapy Oncology Group prospective randomized trials.

Treatment outcomes and quality-of-life issues for patients treated with prostate brachytherapy

The increasing popularity of brachytherapy for treatment of early-stage prostate cancer requires oncology nurses to have a comprehensive knowledge of the disease, its treatment, and management of side effects. Because quality-of-life (QOL) issues have become an important consideration in treatment selection for many patients, oncology nurses must have a thorough understanding of these QOL issues and their management. Armed with knowledge about prostate brachytherapy and its effect on QOL, oncology nurses can offer accurate information and evidence-based symptom management techniques to patients undergoing brachytherapy for prostate cancer.

Recurrent PSA after prostatectomy for prostate cancer: implications of PSA doubling time

After radical prostatectomy for prostate cancer, men frequently develop detectable levels of prostate specific antigen (PSA). A slow rate of increase, as characterized by the PSA doubling time (PSADT) is the principal marker for a favorable prognosis. Data and results presented in 2 recent clinical articles studying cohorts of men with clinical stage T1/T2 prostate cancer are reviewed and used to develop mortality analyses. Life-table analysis shows a mortality ratio of 257% at 5 years for Gleason score < 8, PSA recurrence > 2 years after surgery for clinical stage T1/T2 disease, and PSA doubling time (PSADT) > 10 months. Markov modeling using transition probabilities derived from the clinical articles to develop a life table analysis yields a mortality ratio of 145% at 10 years for similar patients.

Advanced age at diagnosis is an independent predictor of time to death from prostate carcinoma for patients undergoing external beam radiation therapy for clinically localized prostate carcinoma

BACKGROUND

Whether age at diagnosis is predictive of time to prostate carcinoma specific death after external beam radiation therapy (RT) for patients who are diagnosed with clinically localized prostate carcinoma during the prostate specific antigen (PSA) era has not been investigated previously.

METHODS

A multivariate Cox regression analysis was used to evaluate the ability of pretreatment risk group and age at diagnosis to predict time to all causes of death and time to death from prostate carcinoma for 381 patients who underwent RT for clinically localized prostate carcinoma.

RESULTS

Age at diagnosis, as a continuous variable (P(continuous) = 0.04), and risk group (P(categorical) = 0.02) were independent predictors of time to death from prostate carcinoma, whereas only age at diagnosis (P(continuous) = 0.01) was a predictor of time to all causes of death. When analyzed as a categorical variable, beginning at age 73 years, age at diagnosis was an independent predictor (P(categorical) < 0.04) of time to death from prostate carcinoma. Upon further analysis, this finding was limited to high-risk patients. For example, age > or = 75 years at diagnosis predicted for a shorter median time to death from prostate carcinoma (6.3 years vs. 9.7 years; P = 0.002) in high-risk patients.

CONCLUSIONS

Patients with clinically localized, high-risk prostate carcinoma who were diagnosed at age > or = 73 years and were treated with RT had a worse prognosis compared with patients who were diagnosed age < 73 years, raising the possibility that a more aggressive prostate carcinoma biology may develop during andropause.

Metastatic carcinoma of the prostate: identifying prognostic groups using recursive partitioning

PURPOSE While in patients with metastatic prostate cancer median survival is approximately 30 months when treated with hormonal therapy, there is substantial interpatient variation. To explain better the outcome in patients with advanced disease we developed a set of prognostic groups within a large-scale clinical trial. MATERIALS AND METHODS Southwest Oncology Group Study 8894 was a randomized prospective clinical trial that compared orchiectomy and flutamide to orchiectomy and placebo. Using the technique of recursive partitioning we analyzed 5-year survival outcomes using a substantial number of patient, treatment and disease related variables to develop a set of prognostic groups with significant differences in survival. RESULTS Of 1,286 eligible patients 1,076 had sufficient data for analysis. The patient data set was split to allow prognostic group development in the first half of patients, followed by validation in the second half of patients accrued to the study. After pruning the regression tree 4 factors had a major impact on outcome, namely appendicular versus axial disease, performance status 0 versus 1 to 3, prostate specific antigen less than 65 versus 65 ng./ml. or greater and Gleason score less than 8 versus 8 or greater. Using these criteria 3 prognostic groups were developed, including a good (hazards ratio 1), intermediate (hazards ratio 1.8) and poor (hazards ratio 2.8) group. Five-year survival estimates in the 3 groups were 42%, 21% and 9%, respectively. Using the validation test set similar 5-year survival estimates for the 3 groups of 46%, 25% and 14%, respectively.CONCLUSIONS These data from a large-scale randomized clinical trial provide a validated set of easily applied prognostic groups. We hope that our results may be validated by other investigators and we would encourage the future reporting of outcomes in patients with advanced prostate cancer using these prognostic groupings. Risk stratification is helpful for designing clinical trials and individual treatment, and it should be incorporated into future reports of outcomes of patients with metastatic disease.