Ries Kranse

Large-scale randomized prostate cancer screening trials: Program performances in the European randomized screening for prostate cancer trial and the prostate, lung, colorectal and ovary cancer trial

Two large‐scale randomized screening trials, the Prostate, Lung, Colorectal and Ovary (PLCO) cancer trial in the USA and the European Randomized Screening for Prostate Cancer (ERSPC) trial in Europe are currently under way, aimed at assessing whether screening reduces prostate cancer mortality. Up to the end of 1998, 102,691 men have been randomized to the intervention arm and 115,322 to the control arm (which represents 83% of the target sample size) from 7 European countries and 10 screening centers in the USA. The principal screening method at all centers is determination of serum prostate‐specific antigen (PSA). The PLCO trial and some European centers use also digital rectal examination (DRE) as an ancillary screening test. In the core age group (55–69 years), 3,362 of 32,486 men screened (10%) had a serum PSA concentration of 4 ng/ml or greater, which is 1 cut‐off for biopsy (performed in 84%). An additional 6% was referred for further assessment based on other criteria, with much less efficiency. Differences in PSA by country are largely attributable to the age structure of the study population. The mean age‐specific PSA levels are lower in the PLCO trial (1.64 ng/ml [in the age group 55–59 years], 1.80 [60–64 years] and 2.18 [65–69 years) than in the ERSPC trial (1.28–1.71 [55–59], 1.75–2.87 [60–64] and 2.48–3.06 [65–69 years]). Detection rates at the first screen in the ERSPC trial range from 11 to 42/1,000 men screened and reflect underlying differences in incidence rates and screening procedures. In centers with consent to randomization design, adherence in the screening arm is 91%, but less than half of the men in the target population are enrolled in the trial. In population‐based centers in which men were randomized prior to consent, all eligible subjects are enrolled, but only about two‐thirds of the men in the intervention arm undergo screening. Considerable progress has been made in both trials. Enrollment will be completed in 2001. A substantial number of early prostate cancers have been detected. The differences between countries seem to reflect both underlying prostate cancer incidence and screening policy. The trials have the power to show definitive results in 2005–2008.

Complications of transrectal ultrasound-guided systematic sextant biopsies of the prostate: evaluation of complication rates and risk factors within a population-based screening program

OBJECTIVES Screening for prostate cancer to reduce the mortality and morbidity from this disease has become an important issue in recent years. Of all procedures used to diagnose prostate cancer, biopsy of the prostate is the cause of most complications. To evaluate the safety of the screening procedure, we have studied the complications and risk factors for complications within the screened population of the European Randomized Study of Screening for Prostate Cancer (ERSPC), Rotterdam section. METHODS Between June 1994 and July 1996, 1687 transrectal ultrasound-guided systematic sextant biopsies were performed after screening 6198 men through prostate-specific antigen level, digital rectal examination, and transrectal ultrasonography. RESULTS From these 1687 biopsies, 302 cases of prostate cancer were diagnosed. Mild complications such as hematuria and hematospermia were reported frequently with rates of 23.6% and 45.3%, respectively. More severe complications were far less frequently seen. Fever, usually of low grade, was seen after 4.2% of biopsies. Seven men (0.4%) were admitted to a hospital after biopsy. Risk factors for complications could not be identified. CONCLUSIONS Review of the literature concerning transrectal biopsies of the prostate shows that the complication rates within this screened population are comparable to those reported within referred patients. The admittance rate is slightly lower. Transrectal ultrasound-guided systematic sextant biopsy of the prostate is a safe procedure for the diagnosis of prostate cancer within the general population; however, identification of risk factors for complications might further improve the safety of the screening procedure.

Identification of Genetic Markers for Prostatic Cancer Progression

Despite the high incidence of prostate cancer, only limited data are available on genes or chromosomes specifically involved in its initiation and progression. We have applied comparative genomic hybridization to routinely processed, paraffin-embedded, tissues at different times in prostatic tumor progression to screen the tumor genome for gains and losses. Our panel included specimens derived from 56 different patients: 23 patients with primary, prostate-confined carcinomas; 18 patients with regional lymph node metastases; and 15 patients with distant metastases. Chromosome arms that most frequently showed losses, included 13q (55%), 8p (48%), 6q (43%), 5q (32%), 16q (25%), 18q (20%), 2q (18%), 4q (18%), 10q (18%), and Y (16%). Gains were often seen of chromosome arms 8q (36%), 17q (23%), Xq (23%), 7q (21%), 3q (18%), 9q (18%), 1q (16%), Xp (16%). Furthermore, specific high-level amplifications, eg, of 1q21, 1q25, and Xq12 to q13, were found in metastatic cancers. A significant accumulation of genetic changes in distant metastases was observed, eg, loss of 10q (p = 0.03) and gain of 7q (p = 0.03) sequences. In addition, investigation of a potential biomarker identified in previous studies by our group, ie, extra copies of #7 and/or #8, revealed a high prevalence of 7pq and/or 8q gain in the distant metastases (p = 0.02). Importantly, gains were observed more frequently in tumors derived from progressors after radical prostatectomy, than in nonprogressors (mean time of follow-up, 74 months). Specifically, gain of chromosome 7pq and/or 8q sequences appeared an accurate discriminator between the progressors and nonprogressors. Multivariate analysis showed a significant correlation between progressive disease and the number of chromosomes with gains. This correlation also held true when stage (p = 0.007) or grade (p = 0.002) were taken into account. Likewise, this applied for gain of chromosome 7pq and/or 8q sequences (p = 0.03 and p = 0.005 for stage or grade, respectively). Additionally, an increase in the number of chromosomes with gains per case was related to a decrease in biochemical progression-free survival (Ptrend <0.001). More specifically, the gain of 7pq and/or 8q sequences markedly reduced the biochemical progression-free survival (p < 0.001). In conclusion, this study has, firstly, documented the spectrum of chromosomal alterations in subsequent stages of prostate cancer, a number of which had not been described previously. It allowed us to identify chromosomal regions related to advanced tumor stage, ie, loss of 10q24 and gain of 7q11.2 and/or 7q31 sequences. Secondly, gain of 7pq and/or 8q was identified as a potential genetic discriminator between progressors and nonprogressors after radical surgery.

A risk-based strategy improves prostate-specific antigen-driven detection of prostate cancer.

BACKGROUND Screening for prostate cancer (PC) is controversial due to uncertainties about its efficiency. OBJECTIVE We aimed to develop strategies to reduce the number of unnecessary biopsies while still detecting most clinically important PC cases. DESIGN, SETTING, AND PARTICIPANTS In 1850 men initially screened and biopsied (prostate-specific antigen [PSA] value > or =3.0 ng/ml) in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer, we calculated both the probability of having a positive lateralized sextant biopsy [P(biop+)] and the probability of having an indolent cancer [P(ind)] if PC was detected at biopsy (n=541). Analyses of repeat screening included 225 cancers in 1201 men. INTERVENTIONS The P(biop+) was based on applying a logistic regression model that included ultrasound volume, digital rectal exam, and transrectal ultrasound in addition to the PSA value. The P(ind) was based on a recently validated nomogram. MEASUREMENTS AND LIMITATIONS: At initial screening the fraction of positive biopsies was 29% (541 of 1850). Applying an additional P(biop+) cut-off of 12.5% implied that 613 of the 1850 men (33%) would not have been biopsied. This would result in an increase in the positive predictive value (PPV) to 38% (468 of 1237). At repeat screening a similar P(biop+) cut-off would result in an increase in the PPV from 19% (225 of 1201) to 25% (188 of 760). Thirteen percent of PC cases would not have been diagnosed, of which 70% (initial screening) and 81% (repeat screening) could be considered as potentially indolent. None of the deadly PC cases would have been missed. A PSA cut-off of > or =4.0 ng/ml resulted in similar numbers of biopsied cases saved but considerably higher numbers of missed diagnoses. CONCLUSIONS An individualized screening algorithm using other available prebiopsy information in addition to PSA level can result in a considerable reduction of unnecessary biopsies. Very few important PC cases, for which diagnosis at a subsequent screening visit might be too late for treatment with curative intent, would be missed.

The value of screening tests in the detection of prostate cancer. Part I: Results of a retrospective evaluation of 1726 men

OBJECTIVES The ratio between free and total prostate-specific antigen (PSA) in serum (F/T ratio) was shown to improve the differentiation between prostate carcinoma and benign conditions in selected series of patients. In this study the F/T ratio was analyzed for its ability to improve the specificity of total serum PSA, digital rectal examination (DRE), and transrectal ultrasonography (TRUS) for the detection of prostate cancer in an unselected screening population of men identified in the Rotterdam population. METHODS In 1726 men between 55 and 76 years old, 67 prostate carcinomas were detected by DRE, TRUS, and total serum PSA (Abbott IMx, Hybritech Tandem E). The DELFIA ProStatus PSA EQM and ProStatus PSA Free/Total assays (Wallac) were applied in retrospect to determine total and free serum PSA. Age, total prostate and inner zone volumes were taken into consideration. RESULTS Sixty-seven carcinomas were detected, two by TRUS and three by DRE alone. Total serum PSA was the most important single predictor of prostate cancer, followed by DRE. The F/T ratio increased the specificity of total serum PSA in the PSA range between 4.0 and 10.0 ng/mL. However, this improved specificity was not significant, nor for gland volumes restricted to 50 mL or less. CONCLUSIONS The combination of total serum PSA and DRE remains the standard for detection of prostate carcinoma in a screening population. Their specificity may be improved minimally by the F/T ratio, but not significantly in a sample of 1726 screened men. The threshold of the F/T ratio, and the optimal PSA range for its application, remains to be assessed prospectively.

Predictors for biopsy outcome in the European Randomized Study of Screening for Prostate Cancer (Rotterdam region)

In the European Randomized Study of Screening for Prostate Cancer (ERSPC, Rotterdam region), men aged 55–74 years are screened for prostate cancer by prostate‐specific antigen (PSA) sampling, digital rectal examination (DRE), and transrectal ultrasound investigation (TRUS). All men with a PSA ≥4 ng/ml and/or a suspicious DRE and/or a suspicious TRUS are biopsied.

A Graphical Device to Represent the Outcomes of a Logistic Regression Analysis

Ongoing research on the best way to diagnose prostate cancer has yielded and will continue to yield vast amounts of information. Based on, for example, information from prostate cancer screening trials models have been made that enable urologists to predict which man has prostate cancer on the basis of pre‐biopsy data. In patients with screen detected prostate cancer, the presence of indolent disease can now be identified with reasonable certainty by a different model. For these men active surveillance may be a better option than aggressive treatment with its possible side effects as impotence, incontinence and bowel damage. Both models mentioned above are logistic regression models. Nomograms enable their use in daily clinical practice.

Trends in incidence, treatment and survival of patients with stage IV colorectal cancer: a population‐based series

Aim  The incidence, patterns of care and survival were determined in patients with stage IV colorectal cancer (CRC) in a population‐based series.

The European Randomized Study of Screening for Prostate Cancer (ERSPC): An Update

Screening for prostate cancer is controversial. While in some parts of the world screening is practised as a healthcare policy, it is strongly rejected in other areas, because solid evidence of effectiveness of screening combined with early treatment with respect to lowering the mortality of prostate cancer has not been shown. It is for this reason that a large European study is installed to establish or rule out the value of screening for this frequent disease. The present paper presents the goal of the study and elaborates on the value of presently available screening tests. Preliminary results with respect to the first round of screening in the Rotterdam area relating to 32,000 randomized men are presented. Evidence of effectiveness of screening through other studies and mechanisms is discussed.

THE VALUE OF SCREENING TESTS IN THE DETECTION OF PROSTATE CANCER. PART II: RETROSPECTIVE ANALYSIS OF FREE/TOTAL PROSTATE-SPECIFIC ANALYSIS RATIO, AGE- SPECIFIC REFERENCE RANGES, AND PSA DENSITY"

OBJECTIVES The ratio between free and total prostate-specific antigen (PSA) in serum (F/T ratio) was shown to improve the specificity of total serum PSA for the detection of prostate carcinoma in selected populations. In this study, the value of the F/T ratio for screening of prostate cancer was compared with that of age-specific reference ranges for PSA and PSA density (PSAD) by a simulation experiment. METHODS In 1726 men between 55 and 76 years old, 67 prostate carcinomas were detected by application of digital rectal examination (DRE), transrectal ultrasonography (TRUS), and total serum PSA. A serum PSA of 4.0 ng/mL or more, an abnormal DRE, or an abnormal TRUS were the indications to perform 308 biopsies. A simulation was performed in which an F/T ratio of 0.20 (ProStatus PSA Free/Total), age-specific PSA reference ranges, and a PSAD of 0.12 ng/mL/cc were used to study their capability to increase the specificity of total serum PSA in predicting prostate biopsy results. RESULTS Using age-specific PSA reference ranges and DRE as indicators for biopsy, a reduction of 37% (113) of biopsies would have been obtained with a loss of detected cancers of 12% (11). For the use of PSAD and DRE, these numbers were 28% (96) and 11% (7), respectively. Application of a serum PSA of 4.0 ng/mL or more and an F/T ratio of 0.20 or less and an abnormal DRE as indicators for biopsy would reduce the number of biopsies by 37% (112) and the number of detected cancers by 11% (7). The biopsy to prostate cancer ratio of these simulations varied between 3.3 and 3.6. Minimal loss of cancer detection of 3% (2) with a reduction in the number of biopsies of 17% (53) is obtained when TRUS is omitted from the screening protocol. Selecting men by a total serum PSA value of 2.0 ng/mL for further diagnostic workup by TRUS and DRE would have reduced the number of biopsies by 30% (102), and the number of cancers detected by 6% (4). CONCLUSIONS The most cost-effective protocol for screening prostate carcinoma appears to be prescreening by total serum PSA. The F/T ratio might be used to detect carcinomas in the PSA range below 4.0 ng/mL, but the best threshold remains to be assessed.