Cancer surveillance series: interpreting trends in prostate cancer--part I: Evidence of the effects of screening in recent prostate cancer incidence, mortality, and survival rates

Mindless or mindful? Radiation oncologists' perspectives on the evolution of prostate cancer treatment

The evolution of radiation therapy treatment for prostate cancer has been striking over the last 10 years. Advances in brachytherapy (BT), external beam radiotherapy (EBRT), and the combination of EBRT + BT have led to improved biochemical and clinical results. This article describes these advances in the context of the treatment decision process. Key to this process is the assignment of patient risk, which is based on the results of conventional radiation dose and techniques. Using the 1992 AJCC palpation staging system, Gleason score, and pretreatment prostate-specific antigen, two different risk assessment algorithms were compared. Both gave comparable approximations of risk, although the single factor high-risk model was superior in differentiating those patients with the highest probability of failing treatment after radiotherapy. Such criteria are the foundation for treatment selection. Objective findings support BT alone or EBRT alone for low-risk patients, high-dose EBRT or EBRT + BT for intermediate-risk patients, and EBRT + androgen deprivation for high-risk patients. In summary, advances in radiation oncology have led to significant gains in prostate cancer control. Clinical prognostic factor-based patient selection is central to the optimization of outcome.

The natural history of prostate cancer

Predicting the long-term outcome of patients who choose watchful waiting as initial therapy for prostate cancer is difficult. The wide variation in disease progression, the impact of competing medical hazards, and the potential impact of early hormonal therapy that is characteristic of contemporary patients all conspire to compromise survival estimates dating from the pre-PSA era. The survival analysis figure developed by Albertsen et al (Fig. 1) estimates a 15-year survival rate based on patient age and Gleason score at diagnosis from patients diagnosed in the pre-PSA era. Although no effort was made to adjustfor competing medical hazards, patients and clinicians can adjust a patient's chronological age to match his "physiological" age. The advent of widespread PSA testing appears to have advanced the date of diagnosis by approximately 5 years and the onset of secondary treatment by at least as many years. Therefore, the figure describing the natural history of prostate cancer most likely underestimates rather than overestimates survival among men with newly diagnosed, localized prostate cancer who select watchful waiting as their treatment choice. As contemporary databases of men with localized prostate cancer mature, more data on the natural history of this disease will become available. Only time will tell how the use of PSA has altered the precision of historic case-series data.

Prostate cancer in Italy before and during the 'PSA era': survival trend and prognostic determinants

The aim of the study was to investigate the variations in prostate cancer prognosis during a period of major diagnostic change, such as the introduction of the prostate-specific antigen (PSA) test. Data were provided by 14 Italian cancer registries (CRs). Incidence and follow-up information was collected for patients diagnosed from 1978 to 1994. Relative survival was computed taking into account incidence period, age, tumour stage and grade at diagnosis. A multivariate analysis was carried out to evaluate the independent simultaneous effect on survival of some prognostic determinants. A large geographical variability was observed: in 1993-1994 Italian survival rates ranged from 76% to 52%, with a north-south gradient. A striking prognostic improvement (up to +27 percentage points) between the late 1980s and the early 1990s occurred in almost all CRs, particularly with regard to younger patients. Multivariate analysis showed a strong influence of incidence period on survival, also after correction by tumour stage. The slowdown of metastatic cancers suggests that the survival improvement could be due both to the introduction of an effective opportunistic screening and to a quantitative change in the application of clinical treatment, even if the effect of the lead-time bias phenomenon has to be taken into account.

Time trends in biochemical recurrence after radical prostatectomy: results of the SEARCH database

OBJECTIVES

To determine whether in the prostate-specific antigen (PSA) era stage and/or grade migration of patients treated with radical prostatectomy (RP) has occurred. We also examined whether the biochemical recurrence rates after RP have changed with time.

METHODS

A total of 1654 patients from the Shared Equal Access Regional Cancer Hospital (SEARCH) database were analyzed for time trends in age, preoperative PSA level, clinical stage, biopsy Gleason score, prostatectomy Gleason grade, pathologic stage, margin status, and recurrence rates after RP. Results were stratified into three 4-year blocks of time between 1988 and 2002 for analysis.

RESULTS

The preoperative PSA level, patient age, tumor stage, rate of capsular penetration, and lymph node involvement decreased with time. Both biopsy and pathologic Gleason grade steadily increased with time. The positive margin rate and incidence of seminal vesicle involvement remained stable. On multivariate analysis, only serum PSA level (P <0.001) and biopsy Gleason score (P <0.001) were significant independent predictors of the time to recurrence after RP. The year of surgery was not a significant independent predictor of biochemical recurrence after RP in multivariate analysis.

CONCLUSIONS

Despite lower stage and lower PSA levels with time, we found no improvement in PSA recurrence rates over time. This may reflect lead-time bias in detecting PSA recurrence by the use of more sensitive PSA assays in recent years.

Screening for prostate cancer

Epidemiologically, screening is justified by the importance of the disease and the lack of prospects for primary prevention, but evidence from natural history is unhelpful since men are more likely to die with, rather than from, prostate cancer. The available screening tests do not always detect men whose lesions could result in future morbidity or mortality. Evidence is limited for the benefits of treatment for localised cancers detected through screening, whereas the evidence for harm is clear. Observational evidence for the effect of population screening programmes is mixed, with no clear association between intensity of screening and reduced prostate cancer mortality. Screening for prostate cancer cannot be justified in low-risk populations, but the balance of benefit and harm will be more favourable after risk stratification. Prostate cancer screening can be justified only in research programmes designed to assess its effectiveness and help identify the groups who may benefit.

Trends in prostate cancer mortality among black men and white men in the United States

BACKGROUND

Prostate cancer mortality rates in the United States declined sharply after 1991 in white men and declined after 1992 in black men. The current study was conducted to investigate possible mechanisms for the declining prostate cancer mortality rates in the United States.

METHODS

The authors examined and compared patterns of prostate cancer incidence, survival rates, and mortality rates among black men and white men in the United States using the 1969-1999 U.S. prostate cancer mortality rates and the 1975-1999 prostate cancer incidence, survival, and incidence-based mortality rates from the Surveillance, Epidemiology, and End Results (SEER) Program for the U.S. population. The SEER data represent approximately 10% of the U.S. population.

RESULTS

Prostate cancer incidence and mortality rates showed transient increases after 1986, when the U.S. Food and Drug Administration approved the use of prostate specific antigen (PSA) testing. The age-adjusted prostate cancer mortality rates for men age 50-84 years, however, have dropped below the rate in 1986 since 1995 for white men and since 1997 for black men. In fact, for white men ages 50-79 years, the 1998 and 1999 rates were the lowest observed since 1950. Incidence-based mortality rates by disease stage revealed that the recent declines were due to declines in distant disease mortality. Moreover, the decrease in distant disease mortality was due to a decline in distant disease incidence, and not to improved survival of patients with distant disease.

CONCLUSIONS

Similar incidence, survival, and mortality rate patterns are seen in black men and white men in the United States, although with differences in the timing and magnitude of recent rate decreases. Increased detection of prostate cancer before it becomes metastatic, possibly reflecting increased use of PSA testing after 1986, may explain much of the recent mortality decrease in both white men and black men.

Early prostate cancer: is there a need for new treatment options?

Improvements in diagnostic techniques have led to prostate cancer being diagnosed in younger patients and at an earlier stage of disease. The question therefore arises as to what is the best treatment for early prostate cancer. The main issues to be considered are whether the cancer is likely to progress quicker if these patients do not receive early treatment and what the quality of life implications are for patients receiving early treatment. As yet, due to the lack of valid comparisons of treatments, there is no clear "best treatment" for early prostate cancer. A number of clinical trials, comparing current treatments or investigating potential new treatment options for early prostate cancer, are in progress. The results of these should clarify the relative benefits of currently available treatments. This article reviews the latest information on the incidence, prognosis and current treatments for early prostate cancer and discusses the need for new treatments. Potential clinical benefits and cost implications of new treatments for early prostate cancer, such as improved surgical and radiotherapy techniques and adjuvant medical therapy, are also evaluated.

Caveolin-1 expression is a predictor of recurrence-free survival in pT2N0 prostate carcinoma diagnosed in Japanese patients

BACKGROUND

The authors previously identified elevated caveolin-1 expression in human prostate carcinoma and determined that caveolin-1 levels as detected by immunohistochemistry of radical prostatectomy specimens offered novel prognostic information. A higher incidence of caveolin-1 expression also was reported in African-American men compared with white men in the U.S. To explore these ethnic/racial differences in caveolin-1 expression further, the authors evaluated caveolin-1 expression as a predictive marker in Japanese men with prostate carcinoma.

METHODS

Immunohistochemical staining with a caveolin-1 specific antibody was performed on routinely processed paraffin sections from 152 consecutively collected radical prostatectomy specimens. The mean patient age was 64.3 years (range, 49-74 years; median, 64.5 years) and the mean follow-up period was 49.5 months (range, 1.3-103.3 months; median, 48.2 months). Caveolin-1 immunoreactivity was evaluated in association with patient's age; preoperative prostate specific antigen level; clinical stage; and pathologic features including Gleason score, extraprostatic extension, status of surgical margins, seminal vesicle involvement, lymph node involvement, and time to disease progression after surgery.

RESULTS

Positive caveolin-1 immunostaining was detected in 46 of the 152 tumors (30.3%) and was found to be associated significantly with a positive surgical margin (P = 0.022). A higher incidence of caveolin-1 expression tended to be found in patients with poorly differentiated tumors (Gleason score > 7, 6-7, and < 6, 35.0% vs. 34.9% vs. 20.4%, respectively) or in patients with extraprostatic extension versus those without extraprostatic extension (35.4% vs. 24.7%) or patients with lymph node involvement compared with those without lymph node involvement (50% vs. 29.5%), although these differences did not reach statistical significance (P = 0.100, P = 0.150, and P = 0.178, respectively, by the Spearman correlation test). Kaplan-Meier analysis revealed that increased caveolin-1 expression was associated with an increased risk of disease progression at 5 years (P = 0.0122 by the log-rank test). In patients with organ-confined (pT2N0) disease, univariate Cox proportional hazards regression analysis revealed that positive caveolin-1 expression was the only significant predictor of disease recurrence after radical prostatectomy (P = 0.011; hazards ratio = 4.75; and 95% confidence interval, 1.43-15.76).

CONCLUSIONS

The results of the current study confirm that positive caveolin-1 expression is associated with clinical markers of disease progression and is predictive of poor clinical outcome after surgery in Japanese patients with pT2N0 prostate carcinoma.

Prevalence of prostate cancer and prostatic intraepithelial neoplasia in Caucasian Mediterranean males: an autopsy study

BACKGROUND

The prevalence of carcinoma of the prostate gland (CaP) and high-grade prostatic intraepithelial neoplasia (HGPIN) was assessed in a Spanish population, representative of the Caucasian Mediterranean (CM) ethnic group. Data were compared with those described in populations from other geographical regions and in other ethnic groups.

METHODS

CaP and HGPIN were evaluated in a consecutive series of prostatic glands collected at the post-mortem examination of 162 male patients born and living in Spain, aged 20-80 years, and dying from trauma. The glands were sliced every 2-3 mm. All slices were paraffin embedded and sectioned to obtain 5 microm whole-mount sections. To compare the prevalence rate in our series and in other Caucasian populations with that from other geographical areas and other ethnic groups, we used data from the autopsy study performed at the Wayne State University.

RESULTS

Prevalence of CaP is 3.58, 8.82, 14.28, 23.80, 31.7, and 33.33% in the 3rd, 4th, 5th, 6th, 7th, and 8th decades, respectively. The rates of HGPIN were 7.14, 11.75, 35.71, 38.06, 45.40, and 48.15% at the 3rd, 4th, 5th, and 8th decades of life. Both CaP and HGPIN are located preferentially at the peripheral zone of the gland and in 21/27 cases (77.7%), an association between CaP and HGPIN was found. The prevalence of both lesions in CM males is significantly lower than in Caucasian American (CA) and Afro-American (AA) males in all the age groups evaluated.

CONCLUSIONS

Microscopic foci of CaP and HGPIN can be documented in CM males from the 3rd decade of life onwards. The lesions become more frequent and extensive as age increases. The prevalence of both lesions seems to be significantly lower in the CM population than in CA and AA males in all the age groups evaluated.

Educating African-American men about prostate cancer: impact on awareness and knowledge

OBJECTIVES

To determine whether an education program on prostate cancer could improve awareness and knowledge among African-American men. African-American men have the world's highest incidence of prostate cancer and more than twice the mortality compared with white men. Screening programs for prostate cancer have not been successful in attracting African-American participation. One explanation is a poor awareness and knowledge about the disease among this high-risk population.

METHODS

We surveyed 900 African-American adults attending prostate cancer education seminars in community settings throughout Illinois between March 1998 and January 2001. Participants were asked to complete a multiple-choice questionnaire on topics related to prostate cancer. The main outcome measures were a change in awareness and knowledge of prostate cancer after the 1-hour educational seminar.

RESULTS

The mean survey score improved from 26.0% before the seminar to 73.3% after it (P <0.0001). Every multiple-choice question was answered correctly more often after the seminar than before it. Increasing levels of education and income were associated with higher before and after scores (P <0.001). Men achieved a significantly greater score improvement (mean 48.1%) compared with women (mean 41.1%; P = 0.006). Previous screening for prostate cancer was reported by 23% of the participants. Using logistic regression analyses, higher levels of education and income correlated with higher rates of screening. After the seminar, 63.1% stated the intention to undergo screening.

CONCLUSIONS

Our results demonstrate that prostate cancer awareness and knowledge can improve dramatically after a 1-hour seminar on the topic. Additional studies to evaluate the long-term retention of knowledge and impact on behavior are warranted.

KAI1/CD82 protein expression in primary prostate cancer and in BPH associated with cancer

Current prognostic methods in primary prostate cancer cannot accurately identify patients with clinically significant disease at highest risk of developing metastases. This study examined KAI1/CD82 metastasis suppressor expression by quantitative immunohistochemical analysis of benign prostatic hyperplasia (BPH) and prostate cancer specimens. Altogether, prostate cancers exhibited significant KAI1 overexpression compared to BPH not associated with cancer (P = 0.022). Increased KAI1 expression in well and moderately differentiated cancers, above levels seen in BPH, with decreased expression in poorly differentiated cancers was observed. Interestingly, KAI1 expression in BPH associated with cancers was significantly higher than in BPH not associated with cancer (P = 0.009). Thus, KAI1 overexpression may restrain onset and early stage prostate cancer development, whilst its loss may predispose the patient to more aggressive cancer behaviour. Altered KAI1 expression in prostate cancers and BPH associated with cancer may have important diagnostic roles.

Screening for lung cancer: a review of the current literature

STUDY OBJECTIVES

To review the available data on the early detection of lung cancer, with a focus on three technologies: chest x-ray (CXR), sputum cytology, and low-dose CT (LDCT) scanning.

DESIGN, SETTING, PARTICIPANTS

Review of published clinical studies of early detection technologies. The best available evidence on each topic was selected for analysis. Randomized trials were used to evaluate CXR and sputum cytology. Cohort studies, as well as studies providing evidence regarding rates of overdiagnosis and efficacy of initial treatment, were considered in evaluation of LDCT. Study design and results were summarized in evidence tables. Statistical analyses of combined data were not performed.

MEASUREMENT AND RESULTS

Five randomized trials of CXR with or without sputum cytology have been conducted, each which reports disease-specific mortality as well as other end points. None of these studies provide support for the use of either CXR or sputum cytology for the early detection of lung cancer in asymptomatic individuals. Eight completed and ongoing trials of LDCT were identified. All of these studies report the frequency and stage distribution of lung cancers found during initial ("prevalence") screening, and several studies also report rates of detection at the time of annual follow-up. No outcome data on survival or treatment are available. A number of studies support the hypothesis of "overdiagnosis"--that some lung cancers detected by LDCT may behave in an indolent manner.

CONCLUSIONS

The use of either CXR or sputum cytology for the early detection of lung cancer is not supported by the published evidence. The evidence for LDCT appears promising, in that the technology typically identifies lung cancer at an early stage, although corollary studies suggest that these findings in isolation may be misleading. Further high-quality research is needed to better define the role of LDCT in the evaluation of asymptomatic high-risk individuals.

Watchful waiting as a treatment option for localized prostate cancer in the PSA era

The incidence rate of early-stage prostate cancer has dramatically increased since the introduction of the widespread use of PSA testing in developed countries, including Japan. With the downward stage migration there has been much interest in the concept of watchful waiting not only for elderly patients with a life expectancy of less than 10 years but also in younger patients with good social and sexual activity. The results of a recent randomized comparison between radical prostatectomy and watchful waiting for localized disease indicated comparable overall survival but superiority of surgery in disease-specific survival. The predictive value of clinico-pathological parameters including biopsy features and serum PSA seems insufficient to predict tumor growth potential. Our ongoing prospective study is aimed at clarifying whether PSA doubling time assessment for 6 months in patients with favorable biopsy features can be a good indicator for further watchful waiting or immediate aggressive treatment without any survival disadvantage.

Monogene and polygene therapy for the treatment of experimental prostate cancers by use of apoptotic genes bax and bad driven by the prostate-specific promoter ARR(2)PB

We have shown that adenovirus-mediated manipulation of apoptotic genes such as bax could be a therapeutic option for prostate cancer. Unfortunately, the response of experimental prostate tumors to a single therapeutic gene of the apoptotic pathway is short-lived, and most of these tumors relapse after a short period of time. In this investigation we present data generated with adenovirus AvARR(2)PB-Bad, in which the apoptotic gene bad was placed under the control of the dihydrotestosterone (DHT)-inducible third-generation probasin-derived promoter ARR(2)PB. This therapeutic virus was given alone or in combination with other therapeutic viruses to a variety of in vitro and in vivo experimental models of prostate cancer. On infection with AvARR(2)PB-Bad, DHT-induced Bad overexpression occurred specifically in androgen receptor-positive (AR(+)) cells of prostatic derivation. The apoptotic effect of AvARR(2)PB-Bad (group 1) was compared with that of AvARR(2)PB-Bax (which overexpresses the apoptotic protein Bax) (group 2), with that of the combination AvARR(2)PB-Bad plus AvARR(2)PB-Bax (group 3), and with that of the control virus AvARR(2)PB-CAT (group 4) in the cell line LNCaP. In addition to identifying the modality of apoptosis induction by overexpressed Bad, the results suggested that group 3 contained more apoptotic cells than any other group. In additional studies, AR(+) androgen-dependent LNCaP cells or AR(+) and androgen-independent C4-2 cells were injected subcutaneously into nude mice. Four groups of six LNCaP or C4-2 tumors were treated with the same combinations of viruses discussed above for groups 1, 2, 3, and 4. Treatment resulted in decreased tumor size in groups 1, 2, and 3 compared with group 4. There was a better response in group 3 compared with group 2, and in group 2 compared with group 1. A better response in group 3 was confirmed during a 8-week follow-up period, in which no treatment was administered. Two LNCaP and C4-2 tumors of group 3 disappeared at the end of treatment and did not recur after an 8-week follow-up period. The data suggest that polygene therapy with apoptotic molecules is more effective in experimental models of androgen-dependent or -independent prostate cancer than monogene therapy.

Prostate biopsy status and PSA nadir level as early surrogates for treatment failure: analysis of a prostate cancer randomized radiation dose escalation trial

PURPOSE

A positive biopsy after external beam radiotherapy in patients free of any evidence of treatment failure is not synonymous with eventual recurrence. Although biopsy positivity is a predictor of outcome, the utility of biopsy status as a surrogate end point, the effect of radiation dose on biopsy status, and the interrelationships of these associations to prostate-specific antigen (PSA) nadir level are not well-defined. These issues were investigated in a cohort of men with Stage T1-T3 prostate cancer who were randomized to receive between 70 Gy and 78 Gy and were prospectively biopsied at about 2 years after the completion of radiotherapy (RT).

METHODS AND MATERIALS

Of the 301 assessable patients in the trial, 168 underwent planned sextant or greater prostate post-RT biopsies in the absence of biochemical or clinical failure; this group constituted the study cohort. Of the 168 patients, 87 were in the 70-Gy arm and 81 in the 78-Gy arm. Biopsies were classified into four groups: negative (no tumor), atypical/suspicious cells (not diagnostic of carcinoma), carcinoma with treatment effect (CaTxEffect), and carcinoma without treatment effect (CaNoTxEffect). Any diagnosis of carcinoma in the specimen was classified as biopsy positive. Freedom from failure (FFF) included biochemical failure and/or clinical failure. Kaplan-Meier curves were calculated from the completion of RT. For those alive in the study cohort, the median follow-up was 65 months.

RESULTS

The rate of biopsy without tumor was 42%; with atypical cells, it was 28%, with CaTxEffect 21%, and with CaNoTxEffect 9%. The overall biopsy positivity rate (CaTxEffect + CaNoTxEffect) was 30%; 28% in the 70-Gy group and 32% in the 78-Gy group (p = 0.52). The distribution of PSA nadir levels was 73% <or=0.5, 20% >0.5-1.0, 5% >1.0-2.0, and 1% >2.0 ng/mL. Significantly more patients randomized to 78 Gy had a PSA nadir of <or=0.5 ng/mL (80% vs. 67%; p = 0.02). No relationship was found between PSA nadir level and prostate biopsy status. The 5-year FFF rate for those classified as biopsy negative was 84% and for those biopsy positive was 60% (p = 0.0002). Radiation dose did not significantly alter FFF rates by prostate biopsy status. Nadir PSA level correlated with FFF, although this was dependent on the inclusion of the 2 patients with a PSA nadir >2.0 ng/mL.

CONCLUSION

For patients free of treatment failure at the time of prostate biopsy 2 years after RT, the prognosis of no tumor cells was the same as that of atypical/suspicious cells and CaTxEffect was the same as CaNoTxEffect. The biopsy positivity rate was not altered by dose, suggesting that most of the outcome differences between the 70-Gy and 78-Gy groups were due to events occurring before prostate biopsy at 2 years and/or were not entirely dependent on biopsy status. Biopsy status is a strong prognostic factor, but, as an early end point, it may be misleading. PSA nadir appears to have little clinical value in patients treated to doses of >/=70 Gy who are failure free 2 years after RT.

Novel human prostate-specific cDNA: molecular cloning, expression, and immunobiology of the recombinant protein

The differential display-polymerase chain reaction technique was employed to obtain a prostate-specific approximately 300-bp cDNA fragment. On screening the human prostate-lambdagt10 library with this fragment, a full-length approximately 1.5-kb cDNA encoding for a prostate antigen, designated as human novel prostate-specific antigen (hNPSA), was found. Extensive database searches revealed that the hNPSA cDNA is a novel sequence. It has an open reading frame (ORF) of 735-bp encoding for 245 amino acids (aa), with a calculated molecular mass of approximately 27kDa. Hydrophilicity analysis of the deduced aa sequence indicated that hNPSA is a membrane-anchored peptide. Analysis for tissue-specificity by Northern blot and RT-PCR-Southern blot procedures indicated that hNPSA is specifically expressed only in human prostate. The hNPSA (ORF) was subcloned into pET22b(+) vector and expressed using the histidine-tagged gene fusion system. The recombinant (r) protein of approximately 27kDa was purified and antibodies (Ab) were raised in rabbits. The rhNPSA Ab recognized a specific protein band of approximately 35kDa in solubilized human prostate tissue and not in any of the other 10 human tissues tested in the Western blot procedure. The hNPSA expression is upregulated 2.5- to 3-fold, both at the mRNA and protein levels in androgen-dependent LNCaP cells, as compared to normal whole prostate tissue. Antisense, but not the sense, phosphothiorate-conjugated oligonucleotides based on the hNPSA cDNA sequence significantly (p<0.001) inhibited proliferation of LNCaP cells in a concentration-dependent manner. Thus, the novel hNPSA, which has prostate-specific expression and seems to be involved in carcinogenesis, may have applications in the specific diagnosis and treatment of prostate cancer.

Natural experiment examining impact of aggressive screening and treatment on prostate cancer mortality in two fixed cohorts from Seattle area and Connecticut

OBJECTIVE

To determine whether the more intensive screening and treatment for prostate cancer in the Seattle-Puget Sound area in 1987-90 led to lower mortality from prostate cancer than in Connecticut.

DESIGN

Natural experiment comparing two fixed cohorts from 1987 to 1997.

SETTING

Seattle-Puget Sound and Connecticut surveillance, epidemiology, and end results areas.

PARTICIPANTS

Population based cohorts of male Medicare beneficiaries aged 65-79 drawn from the Seattle (n=94 900) and Connecticut (n=120 621) areas.

MAIN OUTCOME MEASURES

Rates of screening for prostate cancer, treatment with radical prostatectomy and external beam radiotherapy, and prostate cancer specific mortality.

RESULTS

The prostate specific antigen testing rate in Seattle was 5.39 (95% confidence interval 4.76 to 6.11) times that of Connecticut, and the prostate biopsy rate was 2.20 (1.81 to 2.68) times that of Connecticut during 1987-90. The 10 year cumulative incidences of radical prostatectomy and external beam radiotherapy up to 1996 were 2.7% and 3.9% for Seattle cohort members compared with 0.5% and 3.1% for Connecticut cohort members. The adjusted rate ratio of prostate cancer mortality up to 1997 was 1.03 (0.95 to 1.11) in Seattle compared with Connecticut.

CONCLUSION

More intensive screening for prostate cancer and treatment with radical prostatectomy and external beam radiotherapy among Medicare beneficiaries in the Seattle area than in the Connecticut area was not associated with lower prostate cancer specific mortality over 11 years of follow up.

The role of caveolin-1 in androgen insensitive prostate cancer

PURPOSE

We summarize the literature regarding androgen insensitive prostate cancer and caveolin-1. Caveolin-1 is a major structural component of caveolae, membrane micro-domains known to have important roles in signal transduction and lipid transport.

MATERIALS AND METHODS

A review of the literature relevant to androgen insensitive caveolin-1 and prostate cancer included the first published report in 1998 through those published in March 2002.

RESULTS

Caveolin-1 expression is increased in primary and metastatic human prostate cancer with highest levels observed after androgen ablation therapy. Recent studies have documented that caveolin-1 is secreted by prostate cancer cells and can be detected in the serum of men with prostate cancer.

CONCLUSIONS

The results presented in this review establish that caveolin-1 is an autocrine/paracrine factor associated with androgen insensitive prostate cancer. They show the potential for caveolin-1 as a biomarker therapeutic target for this important malignancy.

Modeling the impact of the decline in distant stage disease on prostate carcinoma mortality rates

BACKGROUND

The incidence of distant stage prostate carcinoma was relatively flat until 1991 and then started declining rapidly. This decline probably was caused by the shift to earlier stage disease associated with the rapid dissemination of prostate specific antigen (PSA) screening. Prostate carcinoma mortality rates started falling at approximately the same time. In this article, the authors model the potential impact of this stage shift on prostate carcinoma mortality rates given various assumptions concerning the survival of patients with screen-detected local-regional disease.

METHODS

The authors used the CAN*TROL 2 computer model to shift each deficit in the number of patients with distant stage disease to local-regional stage disease and modeled the implications on mortality using a set of base, optimistic, and pessimistic survival assumptions. A base survival assumes that a patient with screen-detected local-regional disease of a certain histologic grade has the same prognosis as a patient with clinically detected local-regional disease of same grade (i.e., an assumption of no length bias for patients with screen-detected disease), whereas the optimistic and pessimistic scenarios assume that survival is better or worse, respectively, than the base survival (i.e., complete cure for patients with favorable grade for the optimistic scenario and no improvements in survival for patients with unfavorable grade for the pessimistic scenario).

RESULTS

Model results were compared with observed mortality trends. Rising age-adjusted mortality rates peaked in 1991 for white males and in 1993 for black males and then fell 21% and 13% for white males and black males, respectively, from 1990 through 1999. Under the modeled stage-shift intervention, mortality rates would fall 18%, 8%, and 19% for both white males and black males under the base, pessimistic, and optimistic assumptions, respectively.

CONCLUSIONS

It is impossible to know what the mortality trends would have been in the absence of the introduction of PSA screening. However, under the base assumption, it appears that the decline in distant stage disease can have a fairly sizable and rapid impact on population mortality. The optimistic scenario is not much improved over the base scenario, which is indicative of the facts that the survival of patients diagnosed with clinical local-regional prostate carcinoma is quite good and that further survival improvements can have only a marginal impact. Under the pessimistic scenario, it appears that something else must be responsible for much of the decline in mortality. Screening trial results from the United States and Europe may verify and isolate the size of any mortality benefit associated with PSA screening. Trial results eventually can be put back into these population models to help quantify the impact of screening, treatment, and other factors on population trends.

Prostate cancer radiation dose response: results of the M. D. Anderson phase III randomized trial

PURPOSE

A randomized radiotherapy dose escalation trial was undertaken between 1993 and 1998 to compare the efficacy of 70 vs. 78 Gy in controlling prostate cancer.

METHODS AND MATERIALS

A total of 305 Stage T1-T3 patients were entered into the trial and, of these, 301 with a median follow-up of 60 months, were assessable. Of the 301 patients, 150 were in the 70 Gy arm and 151 were in the 78 Gy arm. The primary end point was freedom from failure (FFF), including biochemical failure, which was defined as 3 rises in the prostate-specific antigen (PSA) level. Kaplan-Meier survival analyses were calculated from the completion of radiotherapy. The log-rank test was used to compare the groups. Cox proportional hazard regression analysis was used to examine the independence of study randomization in multivariate analysis.

RESULTS

There was an even distribution of patients by randomization arm and stage, Gleason score, and pretreatment PSA level. The FFF rates for the 70- and 78 Gy arms at 6 years were 64% and 70%, respectively (p = 0.03). Dose escalation to 78 Gy preferentially benefited those with a pretreatment PSA >10 ng/mL; the FFF rate was 62% for the 78 Gy arm vs. 43% for those who received 70 Gy (p = 0.01). For patients with a pretreatment PSA <or=10 ng/mL, no significant dose response was found, with an average 6-year FFF rate of about 75%. Although no difference occurred in overall survival, the freedom from distant metastasis rate was higher for those with PSA levels >10 ng/mL who were treated to 78 Gy (98% vs. 88% at 6 years, p = 0.056). Rectal side effects were also significantly greater in the 78 Gy group. Grade 2 or higher toxicity rates at 6 years were 12% and 26% for the 70 Gy and 78 Gy arms, respectively (p = 0.001). Grade 2 or higher bladder complications were similar at 10%. For patients in the 78 Gy arm, Grade 2 or higher rectal toxicity correlated highly with the proportion of the rectum treated to >70 Gy.

CONCLUSION

An increase of 8 Gy resulted in a highly significant improvement in FFF for patients at intermediate-to-high risk, although the rectal reactions were also increased. Dose escalation techniques that limit the rectal volume that receives >or=70 Gy to <25% should be used.

Patient demographic and socioeconomic characteristics in the SEER-Medicare database applications and limitations

Users of the linked SEER-Medicare database commonly perform analyses that focus on the complex interactions among patient characteristics, cancer treatments, and outcomes. The authors review the source and scope of the patient-specific data elements, with a focus on three domains--demographic characteristics, socioeconomic characteristics, and survival status. They offer some concrete recommendations regarding the use of these data elements. In particular, they describe analyses that provide an estimate of the accuracy of the sex and age variables, and raise some cautionary notes about race and ethnicity variables. The authors describe the available measures of socioeconomic status, and recommend, with some caveats, the use of median income measures as a proxy for socioeconomic status. Finally, they describe the available data on date of death, and explain why confidence in these measures is justified.

Assessing a decade of progress in cancer control

The age-adjusted death rate from cancer peaked in the U.S. in 1990, and has declined steadily since then. We assess reasons for this progress by examining trends in cancer mortality by age, gender, and cause, using underlying cause mortality data from the Centers for Disease Control. Mortality rates for 2000 were estimated using models based on 1979 through 1997 mortality data. Indirect standardization was used to calculate the expected number of cancer deaths in 2000, by age, gender, and cause, assuming that the rates in 1990 had not changed. In the U.S. in 2000, there were an estimated 500,000 deaths from cancer; 64,000 (12.7%) fewer than expected, with 51,900 fewer cancer deaths among men and 12,200 fewer deaths among women. The decline in deaths among men resulted from fewer deaths from lung cancer (20,800), colon cancer (6,700), and prostate cancer (12,900). The decline in deaths among women resulted from fewer deaths from breast cancer (11,100) and colon cancer (4,200), but there were more deaths from lung cancer (6,500). Among women over the age of 75, 5,000 more died of cancer than expected. Declines in lung, prostate, and colon cancer deaths among men and breast and colon cancer among women account for 86% of the recent decline in cancer deaths over the past decade.

Patterns and trends in prostate cancer incidence, survival, prevalence and mortality. Part I: international comparisons

The international patterns and trends in prostate cancer incidence, survival, prevalence and mortality were examined. Age-standardized incidence and death rates among men in a variety of countries worldwide were obtained from various sources, survival rates from European sources and elsewhere, and prevalence estimates from the EUROPREVAL study. Results from many published studies were summarized. The incidence of prostate cancer varies widely around the world, with by far the highest rates in the USA and Canada. There has been a gradual increase in the incidence of prostate cancer since the 1960s in many countries and in most continents; there were large increases in the late 1980s and early 1990s in the USA, but increases have also occurred in countries with comparatively low incidence, e.g. India. Survival from prostate cancer improved during the 1970s and 1980s; further increases in the 1990s may be largely a result of earlier diagnosis. There were wide differences in survival across Europe, with rates in the UK well below the average, but all European rates were far below those in the USA. There was wide variation in the prevalence of prostate cancer in Europe; in some countries with high incidence and high life-expectancy, prostate cancers formed approximately 15% of all prevalent cancers in men. Mortality from prostate cancer has also increased in many countries, but to a lesser extent than incidence; this is consistent with the observed trends in survival. Mortality decreased slightly in the mid to late 1990s in several countries, including the USA, Canada, England, France and Austria. Part of the apparent increases in the incidence of prostate cancer has been associated with diagnostic artefacts (particularly detecting preclinical tumours through the increased use of transurethral resection) which may also have had an effect on death certification through the incorrect attribution of prostate cancer as the underlying cause of death. However, the greatest effect on the registration of new cases of prostate cancer has been the increased availability of prostate specific antigen testing during the early- to mid-1990s. Possibly, in addition to the effect of attribution bias, the earlier diagnosis of prostate cancers has contributed to the recent slight decreases in mortality. However, this is unlikely to account for much of the reduction, given the slow development of the disease from onset to death. Changes in disease management are probably more important. There are many strong arguments against introducing population-based screening for prostate cancer.

Molecular biology of the androgen receptor

Androgen receptor (AR) is a member of the steroid hormone receptor family of molecules. AR primarily is responsible for mediating the physiologic effects of androgens by binding to specific DNA sequences that influence transcription of androgen-responsive genes. The three-dimensional structure of the AR ligand-binding domain has shown it is similar to other steroid hormone receptors and that ligand binding alters the protein conformation to allow binding of coactivator molecules that amplify the hormone signal and mediate transcriptional initiation. However, AR also undergoes intramolecular interactions that regulate its interactions with coactivators and influence its activity. A large number of naturally occurring mutations of the human AR gene have provided important information about AR molecular structure and intermolecular interactions. AR is also a critical mediator of prostate cancer promotion, conferring growth signals to prostate cancer cells throughout the natural history of the disease. Late-stage prostate cancer, unresponsive to hormonal deprivation, sustains AR signaling through a diverse array of molecular strategies. Variations in the AR gene may also confer genetic predisposition to prostate cancer development and severity. Further understanding of AR action and new strategies to interfere with AR signaling hold promise for improving prostate cancer therapy.

Serial biopsy results in prostate cancer screening study

PURPOSE

We evaluated prostate biopsy results in men with elevated prostate specific antigen (PSA) levels and/or suspicious digital rectal examination whose initial biopsies did not reveal cancer.

MATERIALS AND METHODS

A total of 2,526 volunteers 40 years old or older underwent 1 or more prostate biopsies for serum PSA concentrations greater than 4.0 ng./ml. (before May 1995) or greater than 2.5 ng./ml. (after May 1995), or digital rectal examination suspicious of cancer. We evaluated compliance with the biopsy recommendation and the cancer detection rate with regard to digital rectal examination results and increasing PSA levels.

RESULTS

Of the men who underwent up to 10 biopsy procedures the serial cancer detection rates were 29%, 17%, 14%, 11%, 9% and 7%, respectively, on biopsy procedures 1 through 6. No significant difference in the yield of cancer on serial biopsies was observed between the groups using the greater than 4.0 ng./ml. and greater than 2.5 ng./ml. cutoff. There was a trend for more cancers detected through serial screening to be organ confined compared with those detected on initial screening (78% versus 69%, p = 0.05). Also, more cancers detected using the greater than 2.5 ng./ml. cutoff were organ confined (80% versus 66%, p = 0.004). Only approximately 1% of the cancers fulfilled the published criteria for clinically insignificant tumors.

CONCLUSIONS

Nearly a quarter of prostate cancers detected in this screening study were missed by the initial biopsy. Of the 962 prostate cancers detected 77% were detected with 1, 91% with 2, 97% with 3 and 99% with 4 biopsy procedures. Serial biopsies detect more organ confined cancers without over detecting clinically unimportant tumors. Future studies are needed to determine whether obtaining more biopsy cores initially would provide earlier prostate cancer detection and avoid unnecessary repeat biopsies.

Doctor's dilemma: incorporating tumor markers into clinical decision-making

Physicians are often faced with the dilemma of how to incorporate tumor markers into routine clinical decision-making. Tumor markers may influence clinical decisions at various stages of cancer therapy: screening, diagnosis, prognosis, detection of early relapse, and monitoring of therapy. We use the examples of beta-human chorionic gonadotrophin (beta-HCG) and alpha-fetoprotein (AFP) as markers for germ cell tumors (GCT), and prostate-specific antigen (PSA) as a marker for prostate cancer, to illustrate their use and limitations for these purposes. We then focus on monitoring and choice of treatment by presenting three vignettes; these highlight the potential benefits and problems associated with the use of tumor markers for monitoring and detection of early relapse in asymptomatic patients.

Geographical epidemiology of prostate cancer in Great Britain

Prostate cancer incidence has increased during recent years, possibly linked to environmental exposures. Exposure to environmental carcinogens is unlikely to be evenly distributed geographically, which may give rise to variations in disease occurrence that is detectable in a spatial analysis. The aim of our study was to examine the spatial variation of prostate cancer in Great Britain at ages 45-64 years. Spatial variation was examined across electoral wards from 1975-1991. Poisson regression was used to examine regional, urbanisation and socioeconomic effects, while Bayesian mapping techniques were used to assess spatial variability. There was an indication of geographical differences in prostate cancer risk at a regional level, ranging from 0.83 (95% CI: 0.78-0.87) to 1.2 (95% CI: 1.1-1.3) across regions. There was significant heterogeneity in the risk across wards, although the range of relative risks was narrow. More detailed spatial analyses within 4 regions did not indicate any clear evidence of localised geographical clustering for prostate cancer. The absence of any marked geographical variability at a small-area scale argues against a geographically varying environmental factor operating strongly in the aetiology of prostate cancer.

Germline mutations in the ribonuclease L gene in families showing linkage with HPC1

Although prostate cancer is the most common non-cutaneous malignancy diagnosed in men in the United States, little is known about inherited factors that influence its genetic predisposition. Here we report that germline mutations in the gene encoding 2'-5'-oligoadenylate(2-5A)-dependent RNase L (RNASEL) segregate in prostate cancer families that show linkage to the HPC1 (hereditary prostate cancer 1) region at 1q24-25 (ref. 9). We identified RNASEL by a positional cloning/candidate gene method, and show that a nonsense mutation and a mutation in an initiation codon of RNASEL segregate independently in two HPC1-linked families. Inactive RNASEL alleles are present at a low frequency in the general population. RNASEL regulates cell proliferation and apoptosis through the interferon-regulated 2-5A pathway and has been suggested to be a candidate tumor suppressor gene. We found that microdissected tumors with a germline mutation showed loss of heterozygosity and loss of RNase L protein, and that RNASEL activity was reduced in lymphoblasts from heterozyogous individuals compared with family members who were homozygous with respect to the wildtype allele. Thus, germline mutations in RNASEL may be of diagnostic value, and the 2-5A pathway might provide opportunities for developing therapies for those with prostate cancer.

Prostate-specific antigen testing in black and white men: an analysis of medicare claims from 1991-1998

OBJECTIVES

To describe the trends in prostate-specific antigen (PSA) use and associated cancer detection among black and white Medicare beneficiaries older than 65 years during the calendar period from January 1991 through December 1998.

METHODS

Medicare claims data were linked with cancer registry data from the Surveillance, Epidemiology and End Results program of the National Cancer Institute. Data from a 5% random sample of men without a diagnosis of prostate cancer were combined with data from prostate cancer cases diagnosed during the calendar period from 1991 to 1998. PSA tests conducted after a diagnosis of prostate cancer were excluded.

RESULTS

PSA use has stabilized among white men, reaching an annual rate of 38% by 1995 and remaining at this level through 1998. The annual rate of use among black men reached 31% by 1998, but was still increasing at that time. By 1996, at least 80% of tests in both blacks and whites were second or later tests. By the end of 1996, 35% of white men and 25% of black men were undergoing testing at least biannually or more frequently. In 1996, 83% of diagnoses in whites and 77% in blacks were preceded by a PSA test.

CONCLUSIONS

Older black men lag slightly behind older white men in their use of the PSA test; however, annual testing rates in blacks have yet to stabilize. In both race groups, an overwhelming majority of diagnoses are associated with a PSA test, whether for screening or diagnostic purposes. Regular screening rates in blacks are substantially lower than in whites, but the regular screening rates are relatively low in both race groups. Should PSA screening prove efficacious, efforts to promote regular use among both black and white men will likely be needed.

Incidence and mortality trends for prostate cancer in 5 French areas from 1982 to 1996

After an increase in the 1980s, incidence and mortality for prostate cancer in North America or England and Wales started to decrease in the early 1990s. The reasons for this evolution are widely debated, notably the importance of early detection. This study describes trends of prostate cancer incidence and mortality in 5 areas in France, where practices of early detection for this cancer are widely used. The 5 French administrative areas, covered by a population-based registry, have a total population of approximately 1,700,000 men. Incidence data from these registries were studied for the period 1982-1995, and mortality data were provided by the Institut National de la Santé et de la Recherche Médicale (INSERM) for the period 1982-1996. Age-Period-Cohort models by Poisson regression were created to characterize these trends. Between 1982 and 1995, 14,699 cases of prostate cancer were registered by the 5 registries under consideration. After a little intensification of the increase in 1987, undoubtedly due to early detection (notably using Prostate-Specific Antigen), the trend of the incidence seems to reverse from 1993. Mortality increased monotonically from 1982-1990 by an average of 1.8% per year, before decreasing annually by an average of 3.3% until 1996. Poisson regressions indicated a period effect on both incidence and mortality data; a small, but significant, cohort effect exists for incidence evolution, showing that elements such as etiologic factors may have an influence. Until results of randomized studies on mass screening are available, the question of individual screening remains; improved knowledge of risk factors could be interesting.

Promoting informed decision making about prostate cancer screening

Because prostate cancer screening with prostate specific antigen is controversial, informed consent is recommended. Physicians are encouraged to discuss facts about prostate specific antigen with patients and to supplement such discussions with informational brochures or videotapes.

Screening for prostate cancer with prostate-specific antigen: beware the biases

BACKGROUND

The evidence relating to the use of prostate-specific antigen (PSA) as a screening test is a highly controversial, as demonstrated by the lack of agreement among experts. There may be biases associated with various studies.

ISSUES

The main controversy is the relatively high prevalence of prostate cancer (PC) found at autopsy compared with the relatively low death rate from the disease. The lack of modifiable risk factors has led to early detection as a strategy to reduce mortality, as there is evidence for a significant burden of disease. Important issues are the accuracy of current screening tests, some attempts to improve on them, and whether there are good prognostic markers. The consequences of PSA testing (usually further testing including biopsy) and outcomes of treatment are presented in terms of mortality and morbidity; quality of life (QOL) must also be considered. Also important are the benefits from, and the difficulties associated with the "informed choice" approach to PSA screening.

CONCLUSION

There is evidence to suggest that biases can have a significant impact on the utility of PSA as a screening test for PC.

Changing face and different countenances of prostate cancer: racial and geographic differences in prostate-specific antigen (PSA), stage, and grade trends in the PSA era

The purpose of this investigation was to examine changes in pretreatment prostate-specific antigen (PSA), stage, and grade over the past decade as a function of race and geographic region. A multiinstitutional database representing 6,790 patients (1,417 African-American, 5,373 white) diagnosed with nonmetastatic prostate cancer between 1988 and 1997 was constructed. PSA, stage, and grade data were tabulated by calendar year and region, and time trend analyses based on race and region were performed. There was an overall decline of PSA of 0.8%/year, which was significant (P = 0.0001), with a faster rate of decline in African-Americans (1.9%/year) than for whites (0.6%/year). The odds ratio (OR) for a stage shift was 1.09, which was significant (P < 0.0001), and this shift was greater in whites. The OR for an overall grade shift was 1.15, which was significant (P < 0.0001). Although grade and PSA trends were similar for the different regions, there were significant regional differences in stage trends. The implications are that the face of prostate cancer has changed over the past decade; i.e., the distributions of stage, grade, and PSA (the most important prognosticators) have changed. In addition, the countenances of that face are different for whites and African-Americans. For African-Americans, this is good news: the stage, grade, and PSA distributions are more favorable now than before. For whites, the trends are more complex and more dependent on region. These findings should be used for future clinical and health-policy decisions in the screening and treatment of prostate cancer.

Trends in the utilization of androgen-deprivation therapy for patients with prostate carcinoma suggest an effect on mortality

BACKGROUND

After a surge in the incidence of prostate carcinoma in the early 1990s, diminishing rates of mortality became apparent in 1993. This decrease in mortality is unlikely to be explained entirely by treatment with curative intent alone following screen-detected cases, because the time frame between detection and mortality remains relatively brief.

METHODS

This study used incidence and initial treatment data from the Detroit area SEER registry between 1973 and 1998 in addition to mortality data covering the Metropolitan Detroit area obtained from the Michigan Department of Community Health. Data for Caucasian and African-American men were analyzed. The use of androgen-deprivation therapy, which evolved during the study period, was evaluated in conjunction with mortality and incidence trend data for consideration of etiologic contributions.

RESULTS

The incidence of prostate carcinoma, as noted previously in national data, increased sharply in 1988, peaking in 1992 in Southeast Michigan, whereas mortality rates began to decrease in approximately 1993, with a sustained decrease to the latest recorded data in 1998. These trends were identical in Caucasians and African Americans. A sharp increase in the use of androgen-deprivation therapy began in 1990. This use of androgen-deprivation therapy is high and sustained for patients with early-stage disease, increases for several years, and then diminishes for patients with regional disease. The use also diminished through the 1990s for patients with late-stage disease, paralleling the decrease in the incidence rate for late-stage disease.

CONCLUSIONS

The pattern of androgen-deprivation therapy usage was consistent with that for hormonal monotherapy and adjuvant and neoadjuvant therapy. These findings suggest that androgen-deprivation therapy may contribute, along with advances in diagnostic techniques and curative therapy with radiation or surgery, toward decreasing prostate carcinoma mortality rates in Southeast Michigan.

Conditional median survival of patients with advanced carcinoma: surveillance, epidemiology, and end results data

BACKGROUND

Conditional survival is clinically useful, particularly for patients with malignant disease who have a poor prognosis. However, there are no published data on the conditional median survival of patients with advanced carcinoma on a population basis.

METHODS

Data on 217,573 patients with breast, colorectal, lung, or prostate carcinoma who were newly diagnosed with distant disease between 1973 and 1995 and who were followed through the end of 1997 were extracted from the Surveillance, Epidemiology, and End Results (SEER) data base of the National Cancer Institute. The Kaplan-Meier method was employed to estimate conditional median survival and 95% confidence intervals at 0-5 years after the initial diagnosis.

RESULTS

The conditional median survival increased as time elapsed after the initial diagnosis. The increase was slowest and almost leveled off among patients with prostate carcinoma. The median survival of patients with breast carcinoma increased relatively linearly with time, i.e., 5-6 months per year. Conversely, there was a rapid increase in the conditional median survival according to the amount of time since diagnosis for patients with lung and colorectal carcinoma. The trend was most pronounced for patients with colorectal carcinoma. At 5 years after the initial diagnosis, the remaining median survival was longest for patients with colorectal carcinoma, almost 6 years (71.5 months), followed by patients with lung carcinoma (52.5 months), breast carcinoma (42.5 months), and prostate carcinoma (34.5 months). Although race was a correlate with initial survival, gender and age had more impact on late conditional survival.

CONCLUSIONS

The conditional median survival provides useful and encouraging information for patients who survive with advanced disease and for healthcare professionals who treat these patients. However, the information should be used carefully, taking the limitations of these data into account.

Relationship of demographic and clinical factors to free and total prostate-specific antigen

OBJECTIVES

To characterize the role of demographic and clinical parameters in the measurements of prostate-specific antigen (PSA), free PSA (fPSA), and percent free PSA (%fPSA).

METHODS

This was a cohort study of volunteers to a randomized screening trial. A central laboratory determined PSA and fPSA for the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. A baseline evaluation of free and total PSA was done for 7183 white, black, Asian, Hispanic, and other male volunteers, aged 55 to 74 years. Comparisons were made across racial and ethnic groups and across a set of clinical parameters from a baseline questionnaire.

RESULTS

The median levels of serum PSA were less than 2.1 ng/mL in each age-race grouping of the study participants. The levels of free and total PSA were higher in black (n = 868, 12%) participants than in white (n = 4995, 70%) and Asian (n = 849, 11.8%) participants. Individuals who identified themselves as ethnically Hispanic (n = 339, 4.7%) had median PSA levels higher than whites who were not Hispanic. The free and total PSA levels increased with age, particularly among men 70 to 74 years old. However, the %fPSA levels showed less variation among the four racial groups or by age. The free and total PSA levels were higher among those who had a history of benign prostatic disease.

CONCLUSIONS

Demographic (age and race/ethnicity) and clinical (history of benign prostatic disease) variables had a moderate effect on the measures of PSA and fPSA and very little effect on %fPSA.

Prostate cancer in Austria: impact of prostate-specific antigen test on incidence and mortality

The aim of the study was to assess the impact of prostate-specific antigen (PSA) testing on prostate cancer mortality in Austria. A join-point regression model and permutation tests were used to identify changes in the slope of age-specific trends respectively calculating the annual percentage change (APC). Age-adjusted incidence increased (P < 0.01) between 1983 and 1997 by 79% from 52.2 to 93.6 cases per 100 000 men/year. Incidence in localized/regional stage disease increased in all ages by 143% from 25.7 to 62.4 cases per 100 000 men/year. Incidence in distant disease decreased (P < 0.01) between 1983 and 1997 in all ages by 38% from 9.5 to 5.9 cases per 100 000 men/year. Incidence in unstaged disease increased (P < 0.01) between 1983 and 1997 in all ages by 300% from 4.5 to 18 cases per 100 000 men/year. Age-adjusted mortality increased (P < 0.05) by 13% from 26.8 in 1983 to 30.3 deaths per 100 000 men/year in 1999. No significant changes of trends in mortality rates were detected in the age groups 50-59 years. In the age group 70-79 years the trend changed (P < 0.05) direction in 1991 and in 1994; 1983 through 1991 APC = 3.52 (95% CI 1.37, 5.72), 1991 through 1994 APC = -10.27 (95% CI -26.20, 9.1) and 1994 through 1999 APC = -0.25 (95% CI -4.55, 4.24). PSA testing increased incidence but no impact on mortality in the target population can be observed so far.