Representativeness of trial participants: linking the EORTC boost-no boost trial to the Netherlands cancer registry.

BACKGROUND AND OBJECTIVES: To evaluate the representativeness of Dutch patients participating in the European Organization for Research and Treatment of Cancer EORTC boost-no-boost trial to the target breast cancer patient population. METHODS: All female breast cancer patients diagnosed between 1989 and 1996, aged ≤70 years, treated with breast-conserving surgery and radiation therapy, were selected from the Netherlands Cancer Registry (NCR) and linked to the EORTC trial database. Baseline characteristics were compared between trial and non-trial participants, for the Dutch population and according to seven participating institutions. Kaplan-Meier curves and multivariable Cox regression were used to explore potential heterogeneity in overall survival between low, medium and high-volume institutes. RESULTS: Overall, 20,880 patients were identified from the NCR: 2,445 of 2,602 (94%) trial participants could be linked, and 18,435 were treated outside the trial. Trial participants had similar age, morphology, topography, laterality and socioeconomic status as non-trial participants, but more often stage I (62.7% vs. 56.4%) tumours and less often adjuvant treatment (22.9% vs. 26.5%). Crude 20-year survival ranged from 52.5% to 57.4%, without significant differences in multivariable analyses. CONCLUSION: This case study showed that participants in the boost-no-boost trial well represented the Dutch target population. Data linkage comes with challenges, but can close the gap between research and clinical practice.

Differences in Treatment and Outcome After Treatment with Curative Intent in the Screening and Control Arms of the ERSPC Rotterdam.

UNLABELLED: Screening for prostate cancer (PCa) results in a favorable stage shift. However, even if screening did not result in a clinically apparent lower stage or grade, it might still lead to less disease recurrence after treatment with curative intent (radical prostatectomy [RP] and radiation therapy [RT]) because the tumor had less time to develop outside the prostate. The outcome after treatment could also differ because of variations in treatment quality (eg, radiation dosage/adjuvant hormonal therapy). To test these hypotheses, we compared differences in the treatment quality of the screening and control arms of the European Randomized Study of Screening for Prostate Cancer (ERSPC) Rotterdam and disease-free survival (DFS) after curative treatment in PCa patients with similar stage and grade. A total of 2595 men were initially treated with RP or RT. In the control arm, RT was more often combined with hormonal therapy; treatment dosage was often ≥69Gy. This most likely resulted from changes over time in treatment that coincided with the later detection in the control arm. DFS was higher in the screening arm in all risk groups. After correction for lead time, these differences were minimal, however. We concluded that treatment quality differed between the screening and control arms of the ERSPC Rotterdam. RT quality was especially superior in the control arm with higher dosages and more often RT in combination with hormonal therapy. Despite these differences favoring the control arm, DFS differences were minimal. PATIENT SUMMARY: We looked at differences in prostate cancer (PCa) treatment and outcome after PCa treatment in men diagnosed after screening and men diagnosed after normal clinical practice. Treatment differed with superior treatment given to men diagnosed in normal clinical practice. We propose a likely explanation for this apparently counterintuitive finding (progressive insight combined with, on average, a later detection of tumors in unscreened men). Although unscreened men received better treatment, this advantage seemed to be outweighed by the advantage associated with the earlier detection, on average, of the tumor in screened men. TRIAL REGISTRATION: ISRCTN49127736.

Stratification based on methylation of TBX2 and TBX3 into three molecular grades predicts progression in patients with pTa-bladder cancer.

The potential risk of recurrence and progression in patients with non-muscle-invasive bladder cancer necessitates followup by cystoscopy. The risk of progression to muscle-invasive bladder cancer is estimated based on the European Organisation of Research and Treatment of Cancer score, a combination of several clinicopathological variables. However, pathological assessment is not objective and reproducibility is insufficient. The use of molecular markers could contribute to the estimation of tumor aggressiveness. We recently demonstrated that methylation of GATA2, TBX2, TBX3, and ZIC4 genes could predict progression in Ta tumors. In this study, we aimed to validate the markers in a large patient set using DNA from formalin-fixed and paraffin-embedded tissue. PALGA: the Dutch Pathology Registry was used for patient selection. We included 192 patients with pTaG1/2 bladder cancer of whom 77 experienced progression. Methylation analysis was performed and log-rank analysis was used to calculate the predictive value of each methylation marker for developing progression over time. This analysis showed better progression-free survival in patients with low methylation rates compared with the patients with high methylation rates for all markers (P<0.001) during a followup of ten-years. The combined predictive effect of the methylation markers was analyzed with the Cox-regression method. In this analysis, TBX2, TBX3, and ZIC4 were independent predictors of progression. On the basis of methylation status of TBX2 and TBX3, patients were divided into three new molecular grade groups. Survival analysis showed that only 8% of patients in the low molecular grade group progressed within 5 years. This was 29 and 63% for the intermediate- and high-molecular grade groups. In conclusion, this new molecular-grade based on the combination of TBX2 and TBX3 methylation is an excellent marker for predicting progression to muscle-invasive bladder cancer in patients with primary pTaG1/2 bladder cancer.

Fertility potential in a cohort of 65 men with previously acquired undescended testes.

PURPOSE: To evaluate testicular function in men with previously acquired undescended testes (AUDT) in whom spontaneous descent was awaited until puberty followed by orchiopexy in case of nondescent. METHODS: Andrological evaluation including paternity, scrotal ultrasound, reproductive hormones, and semen analysis was performed in three groups: men with AUDT, healthy controls, and men with previously congenital undescended testes (CUDT). RESULTS: In comparison with controls, men with AUDT more often had significantly abnormal testicular consistency, smaller testes, lower sperm concentration, and less motile sperm. Except for more often a normal testicular consistency in men with AUDT, no differences were found between men with AUDT and men with CUDT. Also, no differences were found between men with AUDT which had spontaneously descended and men who underwent orchiopexy. CONCLUSIONS: Fertility potential in men with AUDT is compromised in comparison with healthy controls, but comparable with men with CUDT. This suggests that congenital and acquired UDT share the same etiology. No significant difference was found between men who had spontaneous descent and men needing orchiopexy. However, fertility potential is unknown for men after immediate surgery at diagnosis, and this should be a subject for future studies.

A different method of evaluation of the ERSPC trial confirms that prostate-specific antigen testing has a significant impact on prostate cancer mortality.

The advantages and disadvantages of two different methods of analyzing the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial with respect to the effect of prostate-specific antigen (PSA) screening on prostate cancer (PCa) mortality (ie, disease-specific mortality analysis and excess mortality analysis) are discussed in depth. The traditional disease-specific mortality is the best end point, but it could be biased by misclassification of causes of death, and it does not take into account the possible effect of the screening process on other causes of death. Excess mortality analysis overcomes these problems, but the results could be biased if the expected mortality is not corrected for attendance status. Both methods, when applied to the ERSPC trials, demonstrate that no increase in non-PCa mortality occurred in the screening group and confirm that PSA screening decreases PCa mortality.

Overestimation of prostate cancer mortality and other-cause mortality by the Kaplan-Meier method.

INTRODUCTION: To assess the extent of overestimation of the cumulative probability of death by the Kaplan-Meier method with the competing-risks regression analysis as reference approach. MATERIALS AND METHODS: Data were derived from the screening arm of the Rotterdam branch of the European Randomized Study of Screening for Prostate Cancer (ERSPC). The screening arm consisted of 21210 men between the ages of 55 and 74 at study entry. Follow up concerning mortality was complete through 2008. Endpoints were 5 and 10 year cumulative probabilities of prostate cancer death and death from other causes. Relative bias was defined as the ratio of the cumulative probability of death as determined by the Kaplan-Meier method, relative to the cumulative probability obtained by the competing-risks analysis. RESULTS: According to the Kaplan-Meier method, the 5 year cumulative probability of death from prostate cancer was 0.0101, compared with 0.0099 according to the competing-risk analysis [1.8% overestimation]. At 10 year, these numbers were 0.0347 and 0.0321, respectively [8.0% overestimation]. For death from other causes, the cumulative probabilities at 5 year were 0.0399 and 0.0397 according to the Kaplan-Meier and the competing-risks method [0.6% overestimation], respectively. At 10 year, the probabilities were 0.141 and 0.139 [1.7% overestimation], respectively. CONCLUSIONS: When competing events are present, the competing-risks regression analysis is to be preferred over the Kaplan-Meier method in the estimation of the cumulative probability of the event of interest.

Screening for prostate cancer: results of the Rotterdam section of the European randomized study of screening for prostate cancer.

BACKGROUND: Evidence from randomized trials on the effects of screening for prostate cancer (PCa) on disease-specific mortality accumulates slowly with increasing follow-up. OBJECTIVE: To assess data on PCa-specific mortality in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer (ERSPC) trial. DESIGN, SETTING, AND PARTICIPANTS: A randomized controlled trial with randomization after signed, written informed consent (efficacy trial). In the period 1993-1999, a total of 42 376 men aged 54-74 yr were randomized to a screening arm (S-arm) (n = 21 210 with screening every 4 yr, applying a total prostate-specific antigen [PSA] level cut-off ≥ 3.0 ng/ml as biopsy indication) or a control arm (C-arm) (n = 21 166; no intervention). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Number of PCas detected per arm depicted by predefined time periods and prognostic groups. PCa-specific mortality analyses using Poisson regression in age group 55-74 yr at randomization and separately in the predefined age group of 55-69 yr. RESULTS AND LIMITATIONS: After a median follow-up of 12.8 yr, 19 765 men (94.2%) were screened at least once and 2674 PCas were detected (of which 561 [21.0%] were interval PCas). In the C-arm, 1430 PCas were detected, resulting in an excess incidence of 59 PCas per 1000 men randomized (61 PCas per 1000 in age group 55-69 yr). Thirty-two percent of all men randomized have died. PCa-specific mortality relative-risk (RR) reductions of 20.0% overall (age: 55-74 yr; p = 0.042) and 31.6% (age: 55-69 yr; p = 0.004) were found. A 14.1% increase was found in men aged 70-74 yr (not statistically significant). Absolute PCa mortality was 1.8 per 1000 men randomized (2.6 per 1000 men randomized in age group 55-69 yr). The number needed to invite and number needed to manage were 565 and 33, respectively, for age group 55-74 yr, and 392 and 24, respectively, for age group 65-69 yr. Given the slow natural history of the disease, follow-up might be too short. CONCLUSIONS: Systematic PSA-based screening reduced PCa-specific mortality by 32% in the age range of 55-69 yr. The roughly twofold higher incidence in the S-arm underlines the importance of tools to better identify those men who would benefit from screening.

Excess all-cause mortality in the evaluation of a screening trial to account for selective participation.

OBJECTIVE: In addition to disease-specific mortality, a randomized controlled cancer screening trial may be evaluated in terms of excess mortality, in which case no patient-specific information on causes of death is needed. We studied the effect of not accounting for attendance on the calculated excess mortality in a prostate cancer screening trial. METHODS: The numerator of the excess mortality rate related to prostate cancer diagnoses in each study arm equals the excess number of deaths observed in the cancer patients. The estimation of the expected number of deaths in the absence of the prostate cancer diagnoses has to account for the self-selection of those participating in the trial, particularly if the proportion of non-participants is substantial. SETTING: The European prostate cancer screening trial (ERSPC). RESULTS: In the screening arm, non-attendees had roughly twice the mortality rate of attendees. Approximately twice as many cancers were detected in the screening arm compared with the control arm, primarily in attendees. Unless attendance is properly accounted for, the expected mortality of prostate cancer patients in the screening arm is overestimated by 0.9-3.6 deaths per 1000 person-years. CONCLUSIONS: Attendees have a lower all-cause mortality rate (are healthier) and a higher probability of a prostate cancer diagnosis than non-attendees and the men randomized to the control arm. If attendance is not accounted for, the excess mortality and the between-arm excess mortality rate ratio are underestimated and screening is considered more effective than it actually is. These effects may be sizeable, notably if non-attendance is common. Correcting for attendance status is important in the calculation of the excess mortality rate in prostate cancer patients that can be used in conjunction with a disease-specific mortality analysis in a randomized controlled cancer screening trial.

Impacts of a population-based prostate cancer screening programme on excess total mortality rates in men with prostate cancer: a randomized controlled trial.

OBJECTIVES: To assess the effect of screening in terms of excess mortality in the European Randomized Study of Screening for Prostate Cancer (ERSPC). METHODS: A total of 141,578 men aged 55­69 were randomized to systematic screening or usual care in ERSPC sections in Finland, Italy, the Netherlands and Sweden. The excess number of deaths was defined as the difference between the observed number of deaths in the prostate cancer (PC)patients and the expected number of deaths up to 31 December 2006. The expected number was derived from mortality of all study participants before a diagnosis with PC adjusted for study centre,study arm and study attendance. The excess mortality rates were compared between the two study arms. RESULTS: The PC incidence was 9.25 per 1000 person-years in the intervention arm and 5.49 per 1000 person-years in the control arm, relative risk (RR) 1.69 (95% confidence interval [CI]1.62­1.76). The excess mortality among men with PC was 0.29 per 1000 person-years in the intervention arm and 0.37 per 1000 person-years in the control arm; the RR for excess mortality was 0.77 (95% CI 0.55­1.08). The absolute risk reduction in the excess mortality was 0.08 per 1000 person-years. The overall mortality was not significantly different between the intervention and the control arms of the study: RR 0.99 (95% CI 0.96­1.01). CONCLUSIONS: Although the reduction in excess mortality was not statistically significant, the between arm reduction in excess mortality rate was in line with the previously reported 20% reduction in the disease-specific mortality. This finding indicates that the reduction in PC mortality in the ERSPC trial cannot be due to a bias in cause of death adjudication.

Impacts of a population-based prostate cancer screening programme on excess total mortality rates in men with prostate cancer: a randomized controlled trial.

Objectives To assess the effect of screening in terms of excess mortality in the European Randomized Study of Screening for Prostate Cancer (ERSPC). Methods A total of 141,578 men aged 55-69 were randomized to systematic screening or usual care in ERSPC sections in Finland, Italy, the Netherlands and Sweden. The excess number of deaths was defined as the difference between the observed number of deaths in the prostate cancer (PC) patients and the expected number of deaths up to 31 December 2006. The expected number was derived from mortality of all study participants before a diagnosis with PC adjusted for study centre, study arm and study attendance. The excess mortality rates were compared between the two study arms. Results The PC incidence was 9.25 per 1000 person-years in the intervention arm and 5.49 per 1000 person-years in the control arm, relative risk (RR) 1.69 (95% confidence interval [CI] 1.62-1.76). The excess mortality among men with PC was 0.29 per 1000 person-years in the intervention arm and 0.37 per 1000 person-years in the control arm; the RR for excess mortality was 0.77 (95% CI 0.55-1.08). The absolute risk reduction in the excess mortality was 0.08 per 1000 person-years. The overall mortality was not significantly different between the intervention and the control arms of the study: RR 0.99 (95% CI 0.96-1.01). Conclusions Although the reduction in excess mortality was not statistically significant, the between-arm reduction in excess mortality rate was in line with the previously reported 20% reduction in the disease-specific mortality. This finding indicates that the reduction in PC mortality in the ERSPC trial cannot be due to a bias in cause of death adjudication.

The incidence and risk factors of metachronous colorectal cancer: an indication for follow-up.

BACKGROUND: Patients with colorectal cancer are at risk for developing metachronous colorectal cancer. The purpose of posttreatment surveillance is to detect and remove premalignant lesions to prevent metachronous colorectal cancer. OBJECTIVE: The aim of this study was to investigate the incidence of and predictive factors for metachronous colorectal cancer in patients with newly diagnosed colorectal cancer. DESIGN AND PATIENTS: The data on all patients with newly diagnosed colorectal cancer between 1995 and 2006 were obtained from the Rotterdam Cancer Registry in The Netherlands and studied for metachronous colorectal cancer. MAIN OUTCOME MEASURES: The annual incidence rate and the standardized incidence ratios were calculated. RESULTS: In total, colorectal cancer was diagnosed in 10,283 patients; there were 39,974 person-years of follow-up. The mean annual incidence rate of metachronous colorectal cancer was 314/100,000 person-years at risk during 10 years of follow-up, corresponding with a mean annual incidence of 0.3% and a cumulative incidence of 1.1% at 3 years, 2.0% at 6 years, and 3.1% at 10 years. The incidence of metachronous colorectal cancer after resection of a first colorectal cancer is significantly higher than the incidence of colorectal cancer in an age- and sex-matched general population (standardized incidence ratio 1.3, 95% CI 1.1-1.5). This difference is especially seen during the first 3 years after first colorectal cancer diagnosis (standardized incidence ratio 1.4, 95% CI 1.1-1.8). The presence of synchronous colorectal cancer was the only significant risk factor for developing metachronous colorectal cancer (relative risk 13.9, 95% CI 4.7-41.0). CONCLUSIONS: Despite the availability of colonoscopy, metachronous colorectal cancer is still seen during follow-up in patients with colorectal cancer; the highest risk is during the first 3 years after initial diagnosis. For this reason, a follow-up colonoscopy is useful at a short-term interval after colorectal cancer diagnosis. The presence of synchronous colorectal cancer at the time of first colorectal cancer diagnosis is the only predictive risk factor for developing metachronous colorectal cancer. Tailored surveillance programs may be considered in patients with a diagnosis of synchronous tumors.

Prospective validation of a risk calculator which calculates the probability of a positive prostate biopsy in a contemporary clinical cohort.

BACKGROUND: Prediction models need validation to assess their value outside the development setting. OBJECTIVE: To assess the external validity of the European Randomised study of Screening for Prostate Cancer (ERSPC) Risk Calculator (RC) in a contemporary clinical cohort. METHODS: The RC calculates the probability of a positive sextant prostate biopsy (P(posb)) using serum prostate-specific antigen (PSA), results of digital rectal examination, transrectal ultrasound (TRUS) and ultrasound assessed prostate volume. We prospectively validated the RC in 320 biopsied men (55-75 years), with no previous prostate biopsy, included in five Dutch hospitals in 2008-2011. If the P(posb) was ≥ 20% a biopsy was recommended. The performance of the RC was tested by comparing the observed outcomes to predicted probabilities, using the area under the curve (AUC) and decision curves analyses. RESULTS: Compared to the screening cohort, men in the clinical cohort differed. They had higher PSA levels (median 6.8 versus 4.3 ng/ml, p<0.01), less TRUS-lesions (27% versus 34%, p = 0.01) and more prostate cancer (PCa) at biopsy (43% versus 25%, p<0.01). Mainly eight biopsy cores were taken. Despite the differences between these cohorts, the mean observed probability agreed with the mean predicted probability (43% versus 40%). The RC predicted P(posb) better than a model with PSA and digital rectal examination, AUC 0.77 (95% confidence interval (CI) 0.72-0.83) and 0.71 (95%CI 0.65-0.76, p<0.01), respectively. This was confirmed by the decision curves analysis. Under the 20% threshold, 17% (11/63) of the biopsied men were diagnosed with PCa. Two of 11 men had an important cancer (Gleason 3+4). CONCLUSIONS: The ERSPC RC performs well in a Dutch clinical cohort in men with previous PSA tests and contemporary biopsy schemes, and outperforms a PSA and DRE-based approach in the decision to perform a biopsy.

Increased non-prostate cancer death risk in clinically diagnosed prostate cancer.

UNLABELLED: Study Type - Prognosis (case control). Level of Evidence 3a. What's known on the subject? and What does the study add? Treatment of advanced PC might put patients at an increased risk of cardiovascular events. Recent studies have suggested that the excess mortality is lower among men who were diagnosed with screen detected PC in comparison to men with clinically diagnosed PC, possibly due to the use of medications for cardiovascular disease and the change to a healthier lifestyle of men with a screen detected PC. Men with clinically diagnosed PC have an increased risk of death unrelated to PC itself, i.e., the excess mortality is based on an increased risk of dying from other neoplasm and diseases of the circulatory or respiratory system. OBJECTIVE: • To assess the cause-specific mortality unrelated to prostate cancer (PC) itself in patients with screen- and clinically diagnosed PC. PATIENTS AND METHODS: • The present study was conducted among participants of the European Randomized Study of Screening for Prostate Cancer. • Based on consensus of the causes of death committee (CODC), all patients who died from PC were excluded. • In the intervention arm, cases were patients with a screen-detected PC, aged 55-74 years, between 1993 and 2001. • These cases were matched to two controls in whom no cancer was found after biopsy, and two controls in whom no cancer was suspected after screening. In the control arm, cases were patients with clinically diagnosed PC, aged 55-74 years, between 1993 and 2001. These cases were matched to four controls without PC. Matching was done with respect to date of birth, screening and/or diagnosis. Men were followed up to 31 December 2007. RESULTS: • No statistically significant difference in overall mortality between cases and controls in the intervention arm was observed: relative risk (RR) 1.26 (95% confidence interval [CI] 0.96-1.65; P = 0.102) and RR 1.13 (95% CI 0.86-1.47; P = 0.381). • In the control arm, the overall mortality was statistically significantly higher in cases relative to controls: RR 1.43 (95% CI 1.03-2.00; P = 0.033). • This difference was because of an increased risk of dying from neoplasms and disease of the circulatory or respiratory system among cases: RR 1.61 (95% CI 1.12-2.29; P = 0.009). • The present study was limited by the relatively small sample size. CONCLUSIONS: • Increased mortality unrelated to PC itself was observed in men with clinically diagnosed PC, but not in screen-detected PC. • The excess mortality in men with clinically diagnosed PC seems to be as a result of a significantly increased risk of dying from neoplasm and disease of the circulatory or respiratory system. • Results have to be studied more thoroughly in further clinical trials.

The additional value of TGFß1 and IL-7 to predict the course of prostate cancer progression.

BACKGROUND: Given the fact that prostate cancer incidence will increase in the coming years, new prognostic biomarkers are needed with regard to the biological aggressiveness of the prostate cancer diagnosed. Since cytokines have been associated with the biology of cancer and its prognosis, we determined whether transforming growth factor beta 1 (TGFß1), interleukin-7 (IL-7) receptor and IL-7 levels add additional prognostic information with regard to prostate cancer-specific survival. MATERIALS AND METHODS: Retrospective survival analysis of forty-four prostate cancer patients, that underwent radical prostatectomy, was performed (1989-2001). Age, Gleason score and pre-treatment PSA levels were collected. IL-7, IL-7 receptor and TGFß1 levels in prostate cancer tissue were determined by quantitative real-time RT-PCR and their additional prognostic value analyzed with regard to prostate cancer survival. Hazard ratios and their confidence intervals were estimated, and Akaike's information criterion was calculated for model comparison. RESULTS: The predictive ability of a model for prostate cancer survival more than doubled when TGFß1 and IL-7 were added to a model containing only the Gleason score and pre-treatment PSA (AIC: 18.1 and AIC: 6.5, respectively). CONCLUSION: IL-7 and TGFß1 are promising markers to indicate those at risk for poor prostate cancer survival. This additional information may be of interest with regard to the biological aggressiveness of the diagnosed prostate cancer, especially for those patients screened for prostate cancer and their considered therapy.

Towards an optimal interval for prostate cancer screening.

BACKGROUND: The rate of decrease in advanced cancers is an estimate for determining prostate cancer (PCa) screening program effectiveness. OBJECTIVE: Assess the effectiveness of PCa screening programs using a 2- or 4-yr screening interval. DESIGN, SETTING, AND PARTICIPANTS: Men aged 55-64 yr were participants at two centers of the European Randomized Study of Screening for Prostate Cancer: Gothenburg, Sweden (2-yr screening interval, n=4202), and Rotterdam, the Netherlands (4-yr screening interval, n=13 301). We followed participants until the date of PCa, the date of death, or the last follow-up at December 31, 2008, or up to a maximum of 12 yr after initial screening. Potentially life-threatening (advanced) cancer was defined as cancer with at least one of following characteristics: clinical stage ≥T3a, M1, or N1; serum prostate-specific antigen (PSA) >20.0 ng/ml; or Gleason score ≥8 at biopsy. INTERVENTION: We compared the proportional total (advanced) cancer incidence (screen-detected and interval cases), defined as the ratio of the observed number of (advanced) cancers to the expected numbers of (advanced) cancers based on the control arm of the study. MEASUREMENTS: The proportional cancer incidence from the second screening round until the end of observation was compared using a 2- or 4-yr screening interval. RESULTS AND LIMITATIONS: From screening round 2 until the end of observation, the proportional cancer incidence was 3.64 in Gothenburg and 3.08 in Rotterdam (relative risk [RR]: 1.18; 95% confidence interval [CI], 1.04-1.33; p=0.009). The proportional advanced cancer incidence was 0.40 in Gothenburg and 0.69 in Rotterdam (RR: 0.57; 95% CI, 0.33-0.99; p=0.048); the RR for detection of low-risk PCa was 1.46 (95% CI, 1.25-1.71; p<0.001). This study was limited by the assumption that PSA testing in the control arm was similar in both centers. CONCLUSIONS: A 2-yr screening interval significantly reduced the incidence of advanced PCa; however, the 2-yr interval increased the overall risk of being diagnosed with (low-risk) PCa compared with a 4-yr interval in men aged 55-64 yr. Individualized screening algorithms must be improved to provide the strategy for this issue.

Prevalence and prognosis of synchronous colorectal cancer: a Dutch population-based study.

BACKGROUND: A noticeable proportion of colorectal cancer (CRC) patients are diagnosed with synchronous CRC. Large population-based studies on the incidence, risk factors and prognosis of synchronous CRC are, however, scarce, and are needed for better determination of risks of synchronous CRC in patients diagnosed with colonic neoplasia. METHODS: All newly diagnosed CRC between 1995 and 2006 were obtained from the Rotterdam Cancer Registry in The Netherlands, and studied for synchronous CRC. RESULTS: Of the 13,683 patients diagnosed with CRC, 534 patients (3.9%) were diagnosed with synchronous CRC. The risk of having synchronous CRC was significantly higher in men (OR 1.54, 95% CI 1.29-1.84) and in patients aged >70 years (OR 1.83, 95% CI 1.39-2.40). Synchronous CRC patients had a significantly higher risk of distant metastases (OR 1.69, 95% CI 1.27-2.26). In 34% (184/534) the two tumours were located in different surgical segments. Five-year relative survival of synchronous CRC was similar to patients with solitary CRC after multivariate adjustment for the presence of distant metastases. CONCLUSION: One out of 25 patients diagnosed with CRC presents with synchronous CRC. In the multivariate analysis, survival of patients with synchronous CRC was similar to patients with solitary CRC, when corrected for the presence of distant metastases at first presentation. One third of the synchronous CRC were located in different surgical segments, which stresses the importance of performing total colon examination preferably prior to surgery.

Prediction of prostate cancer in unscreened men: external validation of a risk calculator.

BACKGROUND: Prediction models need external validation to assess their value beyond the setting where the model was derived from. OBJECTIVE: To assess the external validity of the European Randomized study of Screening for Prostate Cancer (ERSPC) risk calculator (www.prostatecancer-riskcalculator.com) for the probability of having a positive prostate biopsy (P(posb)). DESIGN, SETTING AND PARTICIPANTS: The ERSPC risk calculator was based on data of the initial screening round of the ERSPC section Rotterdam and validated in 1825 and 531 men biopsied at the initial screening round in the Finnish and Swedish sections of the ERSPC respectively. P(posb) was calculated using serum prostate specific antigen (PSA), outcome of digital rectal examination (DRE), transrectal ultrasound and ultrasound assessed prostate volume. MEASUREMENTS: The external validity was assessed for the presence of cancer at biopsy by calibration (agreement between observed and predicted outcomes), discrimination (separation of those with and without cancer), and decision curves (for clinical usefulness). RESULTS AND LIMITATIONS: Prostate cancer was detected in 469 men (26%) of the Finnish cohort and in 124 men (23%) of the Swedish cohort. Systematic miscalibration was present in both cohorts (mean predicted probability 34% versus 26% observed, and 29% versus 23% observed, both p<0.001). The areas under the curves were 0.76 and 0.78, and substantially lower for the model with PSA only (0.64 and 0.68 respectively). The model proved clinically useful for any decision threshold compared with a model with PSA only, PSA and DRE, or biopsying all men. A limitation is that the model is based on sextant biopsies results. CONCLUSIONS: The ERSPC risk calculator discriminated well between those with and without prostate cancer among initially screened men, but overestimated the risk of a positive biopsy. Further research is necessary to assess the performance and applicability of the ERSPC risk calculator when a clinical setting is considered rather than a screening setting.

Balancing the harms and benefits of early detection of prostate cancer.

BACKGROUND: The benefits of prostate cancer screening on an individual level remain unevaluated. METHODS: Between 1993 and 1999, a total of 43,987 men, aged 55-74 years, were included in the intervention arm of the European Randomized Study of Screening for Prostate Cancer (ERSPC) section in the Netherlands, Sweden, and Finland. A total of 42,503 men, aged 55-74 years, were included in a clinical population in Northern Ireland. Serum prostate-specific antigen (PSA) <20.0 ng/mL was measured in all men at study entry. All men were followed for prostate cancer incidence and causes of death until December 31, 2006. RESULTS: The adjusted absolute difference in prostate cancer specific mortality between the intervention population and the clinical population increased with increasing PSA level at study entry, ie, 0.05 per 10,000 person-years for men who had a serum PSA level of 0.0-1.9 ng/mL and 8.8 per 10,000 person-years for men who had a serum PSA level of 10-19.9 ng/mL. To evaluate the risks of early detection, the number needed to investigate (NNI) and number needed to treat (NNT) to save 1 death from prostate cancer were calculated. Both NNI and NNT were higher for those who had lower PSA levels at study entry. The NNI was 24,642 men for patients who had a serum PSA level of 0.0-1.9 ng/mL and was 133 men for patients who had a serum PSA level of 10-19.9 ng/mL; the NNT was 724 men for patients who had a serum PSA level of 0.0-1.9 ng/mL and was 60 men for patients with a serum PSA level of 10-19.9 ng/mL. CONCLUSIONS: For men with a low serum PSA level, the benefits of aggressive investigation and treatment may be limited because they are associated with a large increase in cumulative incidence and potential overtreatment.

Disease-specific mortality may underestimate the total effect of prostate cancer screening.

OBJECTIVES: To study the difference between the disease-specific and excess mortality rate in the European Randomized Study of Screening for Prostate Cancer section Rotterdam. METHODS: A total of 42,376 men were randomized to systematic screening or usual care. The excess number of deaths was defined as the difference between the observed number of deaths in the prostate cancer (PC) patients and the expected number of deaths up to 31 December 2006. The expected number was derived from mortality of all study participants before a possible diagnosis with PC. The disease-specific mortality rate was based on the number of men who died from PC. The excess mortality rate based on the arm-specific excess number of deaths and the disease-specific mortality rate were compared between the two study arms. RESULTS: The overall mortality rate was not significantly different between the intervention and the control arms of the study: RR 1.02 (95% CI 0.98-1.07). The disease-specific mortality rate was 0.42 men per 1000 person-years in the intervention and 0.48 men per 1000 person-years in the control arm: RR 0.86 (95% CI 0.64-1.17). The excess mortality rate was 0.40 per 1000 person-years in the intervention arm and 0.61 men per 1000 person-years in the control arm, and the RR for excess mortality was 0.66 (95% CI 0.39-1.13). CONCLUSIONS: In contrast to the disease-specific mortality rates an increased difference in the excess mortality rates was observed between the two arms. This observation may be due to a systematic underestimation of the disease-specific deaths, and/or an additional disease-related mortality that is measured by an excess mortality analysis but not by a disease-specific mortality.