High accuracy of Swedish death certificates in men participating in screening for prostate cancer: A comparative study of official death certificates with a cause of death committee using a standardized algorithm

Risk of prostate cancer death in men diagnosed with prostate cancer at cystoprostat-ectomy. A nationwide population-based study

BACKGROUND AND AIMS

One out of three men who undergo cystoprostatectomy for bladder cancer is diagnosed with incidental prostate cancer (PCa) at histopathological examination. Many of these men are PSA tested as part of their follow-up, but it is unclear if this is needed. The aim of this study was to assess the risk of PCa death in these men and the need of PSA-testing during follow-up.

METHODS

Between 2002 and 2020, 1,554 men were diagnosed with PCa after cystoprostatectomy performed for non-metastatic bladder cancer and registered in the National Prostate Cancer Register (NPCR) of Sweden. We assessed their risk of death from PCa, bladder cancer and other causes up to 15 years after diagnosis by use of data in The Cause of Death Register. The use of androgen deprivation therapy (ADT) as a proxy for PCa progression was assessed by fillings in The Prescribed Drug Register.

RESULTS

Fifteen years after diagnosis, cumulative incidence of death from PCa was 2.6% (95% CI 2.3%-2.9%), from bladder cancer 32% (95% CI: 30%-34%) and from other causes 40% (95% CI: 36%-44%). Only 35% of men with PCa recorded as primary cause of death in The Cause of Death Register had started ADT before date of death, indicating sticky-diagnosis bias with inflated risk of PCa death.

CONCLUSIONS

For a large majority of men diagnosed with incidental PCa at cystoprostatectomy performed for bladder cancer, the risk of PCa death is very small so there is no rationale for PSA testing during follow-up.

Risk of colorectal adenocarcinoma in men receiving androgen deprivation therapy for prostate cancer; a nationwide cohort study

PURPOSE

To assess whether androgens play a role in explaining the sex related differences in the incidence of colorectal cancer (CRC).

METHODS

A nationwide matched cohort study was conducted employing the Prostate Cancer data Base Sweden (PCBaSe) 4.0 during the study period 2006-2016. Prostate cancer (PC) patients receiving androgen deprivation therapy (ADT) were treated as exposed. Prostate cancer-free men from the general population were randomly selected and matched to the index case by birth year and county of residence, forming the unexposed group. All were followed until a diagnosis of CRC, death, emigration, or end of the study period. The risk of CRC among ADT exposed PC patients compared to unexposed cancer-free men was calculated using a flexible parametric survival model and expressed as hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

There was an increased risk of CRC among ADT exposed PC patients compared to unexposed cancer-free men (HR 1.27 [95% CI 1.15-1.41]), in particular an increased risk of adenocarcinoma of the colon (HR 1.33 [95% CI 1.17-1.51]) and more specifically an increased risk of adenocarcinoma of the distal colon (HR 1.53 [95% CI 1.26-1.85]). Examination of latency effects yielded significantly decreased HRs over time for CRC (p = 0.049 for trend).

CONCLUSIONS

This population-based study found an increased risk of CRC among PC patients exposed to ADT, specifically adenocarcinoma of the distal colon, which indicates an increased association between ADT (PC + ADT) and CRC but not a positive dose-response trend questioning a true causal effect.

Evidence of cancer progression as the cause of death in men with prostate cancer in Sweden

OBJECTIVE

To assess the strength of the evidence indicative of prostate cancer (PCa) progression as the adjudicated cause of death, according to age at death and PCa risk category.

PATIENTS AND METHODS

Using data from the Prostate Cancer data Base Sweden, we identified a study frame of 5543 men with PCa registered as the cause of death according to the Cause of Death Register. We assessed the evidence of PCa progression through a review of healthcare records for a stratified sample of 495/5543. We extracted data on prostate-specific antigen levels, presence of metastases on imaging, and PCa treatments, and quantified the evidence of disease progression using a points system.

RESULTS

Both no evidence and moderate evidence for PCa progression was more common in men aged >85 years at death than those aged <85 years (29% vs 14%). Among the latter, the proportion with no evidence or moderate evidence for PCa progression was 21% for low-risk, 14% for intermediate-risk, 8% for high-risk, and 0% for metastatic PCa. In contrast, in men aged >85 years, there was little difference in the proportion with no evidence or moderate evidence of PCa progression between PCa risk categories; 31% for low-risk, 29% for intermediate-risk, 29% for high-risk, and 21% for metastatic PCa. Of the 5543 men who died from PCa, 13% (95% confidence interval 5-19%) were estimated to have either no evidence or moderate evidence of PCa progression.

CONCLUSIONS

Weak evidence for PCa progression as cause of death was more common in older men with PCa and in those with low-risk PCa. This has implications for interpretation of mortality statistics especially when assessing screening and early treatment of PCa because the beneficial effect of earlier diagnosis could be masked by erroneous adjudication of PCa as cause of death in older men, particular those with localised disease at diagnosis.

Objectively confirmed gastroesophageal reflux disease and risk of atrial fibrillation: a population-based cohort study in Sweden

OBJECTIVE

This study aimed to determine the risk of atrial fibrillation in patients with objectively confirmed GERD.

METHODS

This was a nationwide population-based cohort study between 2005 and 2018, including the majority ( n = 8 421 115) of all Swedish adult residents (≥18 years). Within this cohort, the exposed group were all individuals with a diagnosis of esophagitis or Barrett's esophagus, and the unexposed group was made up of five times as many individuals without any GERD, matched by age, sex, and calendar year. The outcome was the first diagnosis of atrial fibrillation. Cox regression provided hazard ratios (HRs) with 95% confidence intervals (CIs), adjusted for confounders.

RESULTS

Among 118 013 individuals with esophagitis or Barrett's esophagus and 590 065 without GERD, 7042 (6.0%) and 40 962 (6.9%) developed atrial fibrillation, respectively. The risk of atrial fibrillation among patients with GERD was 13% increased within the first year of diagnosis (HR, 1.13; 95% CI, 1.06-1.20), but was not increased after that. Among individuals aged less than 60 years, the HR of atrial fibrillation was 55% increased within the first year of diagnosis (HR, 1.55; 95% CI, 1.27-1.88), and this association remained increased after the first year (HR, 1.14; 95% CI, 1.06-1.22). No association was found in older participants (≥60 years). Results were similar in men and women.

CONCLUSION

This large population-based cohort study indicates that objectively determined GERD increases the risk of atrial fibrillation shortly after diagnosis in men and women younger than 60 years.

Evidence of overestimating prostate cancer mortality in Estonia: a population-based study

BACKGROUND

Prostate cancer (PC) mortality statistics in Estonia has shown inconsistencies with incidence and survival trends. The aim of this population-based study was to assess the accuracy of reporting PC as the underlying cause of death and estimate the effect of misattribution in assigning cause of death on PC mortality rates.

MATERIAL AND METHODS

The Estonian Causes of Death Registry (CoDR) and Cancer Registry provided data on all men in Estonia who died in 2017 and had a mention of PC on any field of the death certificate or had a lifetime diagnosis of PC. A blinded review of medical records was conducted by an expert panel to ascertain whether the underlying cause was PC or other death. We estimated the agreement between the underlying causes of death registered at the CoDR and those ascertained by medical review and calculated corrected mortality rates.

RESULTS

The study population included 655 deaths. Among 277 PC deaths registered at CoDR, 164 (59%) were verified by medical review. Among 378 other deaths registered at CoDR, 17 (5%) were ascertained as PC deaths by medical review. In total, the number of PC deaths decreased from 277 to 181 and the corrected age standardized (world) mortality rate decreased from 20 to 13 per 100 000 (1.5-fold overestimation, 95% confidence interval 1.2-1.9).

CONCLUSIONS

PC mortality statistics in Estonia should be interpreted with caution and possible overestimation considered when making policy decisions. Quality assurance mechanisms should be reinforced in the whole death certification process.

Biochemical recurrence after radical prostatectomy - a large, comprehensive, population-based study with long follow-up

OBJECTIVE

We evaluated long-term risk for biochemical recurrence and subsequent prognosis in a population-based cohort.

MATERIAL AND METHODS

We used register-based data to evaluate 6 675 consecutive patients having radical prostatectomy in Västra Götaland county in Sweden during 1995-2014. Patients were followed until death or end of study, 31 December 2014. Data were collected from registers on national, regional and local level and linked by means of the Swedish personal identity number. Biochemical recurrence was defined as PSA ≥0.2 ng/ml; failure as hormonal treatment, metastasis or prostate cancer death. Survival analysis was used to estimate time to biochemical recurrence and time to failure after biochemical recurrence for patients with 0 - 2 years, 2-5 years, 5-10 years and >10 years interval to biochemical recurrence, respectively.

RESULTS

A total of 1214 men had biochemical recurrence during follow-up. Biochemical recurrence-free survival was 83% (95% confidence interval [CI] 82-84%), 75% (95% CI 74-77%) and 69% (95% CI 67-71%) at 5, 10 and 15 years, respectively. Cumulative incidence of failure for all patients 15 years after biochemical recurrence was 50% (95% CI 43-55%) in competing risk analysis .The risk of failure after biochemical recurrence was highest among patients having biochemical recurrence within 2 years from surgery. Incomplete data on PSA-history is a limitation.

CONCLUSIONS

The risk for biochemical recurrence persists 15 years after surgery. Follow-up should continue as long as treatment would be considered in case of recurrent disease.

Changes in Characteristics of Men with Lethal Prostate Cancer During the Past 25 Years: Description of Population-based Deaths

Background

Attempts to reduce prostate cancer (PC) mortality require an understanding of temporal changes in the characteristics of men with lethal PC.

Objective

To describe the diagnostic characteristics of and time trends for a nationwide population-based cohort of Swedish men who died from PC between 1992 and 2016.

Design, setting, and participants

Men with PC as the underlying cause of death from 1992 to 2016 according to the Swedish Cause of Death Register were included in the study. Characteristics at diagnosis were collected via links to other nationwide registries using personal identity numbers.

Outcome measurements and statistical analysis

Data on disease duration, age at death, and risk category were analyzed. Missing data for risk categories for men with an early date of PC diagnosis were imputed according to the method of chained equations.

Results and limitations

Between 1992 and 2016, age-standardized PC mortality decreased by 25%. Median PC disease duration increased from 3.3 yr (interquartile range [IQR] 1.6–6.3) to 5.9 yr (IQR 2.5–10.3) and the median age at death from PC increased from 78.9 yr (IQR 73.3–84.2) to 82.2 yr (IQR 75.2–87.5). The proportion of men with localized disease at diagnosis who died from PC increased from 34% to 48%, while the rate of distant metastases at diagnosis decreased from 56% to 42%. The rate of distant metastases at diagnosis was highest among the youngest men. Treatment trajectories could not be described owing to the large proportion of missing data before the start of registration in the National Prostate Cancer Registry.

Conclusion

Age-standardized PC mortality has decreased substantially since 1992. However, there is still a high proportion of men who die from PC who had localized disease at diagnosis, which indicates that more attention is needed to identify the underlying causes to prevent disease progression. Since the proportion of men with distant metastases at diagnosis remains high, early detection of lethal tumors is essential to further reduce PC mortality.

Patient summary

We investigated the characteristics of men who died from prostate cancer in Sweden between 1992 and 2016. We found that men with lethal prostate cancer live longer and are older when they die today in comparison to men who died at the beginning of the study period. However, the proportion of men with distant metastases at diagnosis remains high, which is why early detection of lethal tumors is essential to reduce mortality.

Association of 5α-Reductase Inhibitors With Prostate Cancer Mortality

Importance

There is evidence that 5α-reductase inhibitors (5-ARIs), a standard treatment of benign prostate hyperplasia, are associated with a decrease in the incidence of prostate cancer (PCa). However, studies to date have had conflicting results regarding the association with prostate cancer mortality (PCM).

Objective

To evaluate the association of treatment with 5-ARIs with PCM in men without a prior diagnosis of PCa.

Design, Setting, and Participants

This population-based cohort study was conducted in Stockholm, Sweden, between January 1, 2007, and December 31, 2018, and included 429 977 men with a prostate-specific antigen (PSA) test within the study period. Study entry was set to 1 year after the first PSA test. Data were analyzed from September 2021 to December 2021.

Exposures

After their initial PSA test, men with 2 or more newly dispensed prescriptions of 5-ARI, finasteride, or dutasteride were considered 5-ARI users (n = 26 190).

Main Outcomes and Measures

Primary outcome was PCM. Cox proportional hazards regression models were used to calculate multivariable-adjusted hazard ratios (HRs) and 95% CIs for all-cause mortality and PCM.

Results

The study cohort included 349 152 men. The median (IQR) age for those with 2 or more filled prescriptions of 5-ARI was 66 (61-73) years and 57 (50-64) years for those without. The median follow-up time was 8.2 (IQR, 4.9-10) years with 2 257 619 person-years for the unexposed group and 124 008 person-years for the exposed group. The median exposure to treatment with 5-ARI was 4.5 (IQR, 2.1-7.4) years. During follow-up, 35 767 men (8.3%) died, with 852 deaths associated with PCa. The adjusted multivariable survival analysis showed a lower risk of PCM in the 5-ARI group with longer exposure times (0.1-2.0 years: adjusted HR, 0.89; 95% CI, 0.64-1.25; >8 years: adjusted HR, 0.44; 95% CI, 0.27-0.74). No statistically significant differences were seen in all-cause mortality between the exposed and unexposed group. Men treated with 5-ARIs underwent more PSA tests and biopsies per year than the unexposed group (median of 0.63 vs 0.33 and 0.22 vs 0.12, respectively).

Conclusions and Relevance

The results of this cohort study suggest that there was no association between treatment with 5-ARI and increased PCM in a large population-based cohort of men without a previous PCa diagnosis. Additionally, a time-dependent association was seen with decreased risk of PCM with longer 5-ARI treatment. Further research is needed to determine whether the differences are because of intrinsic drug effects or PCa testing differences.

Prognostic Utility of the Gleason Grading System Revisions and Histopathological Factors Beyond Gleason Grade

Background

The International Society of Urological Pathology (ISUP) revised the Gleason system in 2005 and 2014. The impact of these changes on prostate cancer (PCa) prognostication remains unclear.

Objective

To evaluate if the ISUP 2014 Gleason score (GS) predicts PCa death better than the pre-2005 GS, and if additional histopathological information can further improve PCa death prediction.

Patients and Methods

We conducted a case–control study nested among men in the National Prostate Cancer Register of Sweden diagnosed with non-metastatic PCa 1998–2015. We included 369 men who died from PCa (cases) and 369 men who did not (controls). Two uro-pathologists centrally re-reviewed biopsy ISUP 2014 Gleason grading, poorly formed glands, cribriform pattern, comedonecrosis, perineural invasion, intraductal, ductal and mucinous carcinoma, percentage Gleason 4, inflammation, high-grade prostatic intraepithelial neoplasia (HGPIN) and post-atrophic hyperplasia. Pre-2005 GS was back-transformed using i) information on cribriform pattern and/or poorly formed glands and ii) the diagnostic GS from the registry. Models were developed using Firth logistic regression and compared in terms of discrimination (AUC).

Results

The ISUP 2014 GS (AUC = 0.808) performed better than the pre-2005 GS when back-transformed using only cribriform pattern (AUC = 0.785) or both cribriform and poorly formed glands (AUC = 0.792), but not when back-transformed using only poorly formed glands (AUC = 0.800). Similarly, the ISUP 2014 GS performed better than the diagnostic GS (AUC = 0.808 vs 0.781). Comedonecrosis (AUC = 0.811), HGPIN (AUC = 0.810) and number of cores with ≥50% cancer (AUC = 0.810) predicted PCa death independently of the ISUP 2014 GS.

Conclusion

The Gleason Grading revisions have improved PCa death prediction, likely due to classifying cribriform patterns, rather than poorly formed glands, as Gleason 4. Comedonecrosis, HGPIN and number of cores with ≥50% cancer further improve PCa death discrimination slightly.

Intervention-related Deaths in the European Randomized Study of Screening for Prostate Cancer

Background

Identification of intervention-related deaths is important for an accurate assessment of the ratio of benefit to harm in screening trials.

Objective

To investigate intervention-related deaths by study arm in the European Randomized Study of Prostate Cancer Screening (ERSPC).

Design, setting, and participants

ERSPC is a multicenter trial initiated in the 1990s to investigate whether screening on the basis of prostate-specific antigen (PSA) can decrease prostate cancer mortality. The present study included men in the core age group (55–69 yr: screening group n = 112 553, control group n = 128 681) with 16-yr follow-up.

Outcome measurements and statistical analysis

Causes of death among men with prostate cancer in ERSPC were predominantly evaluated by independent national committees via review of medical records according to a predefined algorithm. Intervention-related deaths were defined as deaths caused by complications during the screening procedure, treatment, or follow-up. Descriptive statistics were used for the results.

Results and limitations

In total, 34 deaths were determined to be intervention-related, of which 21 were in the screening arm and 13 in the control arm. The overall risk of intervention-related death was 1.41 (95% confidence interval 0.99–1.99) per 10 000 randomized men for both arms combined and varied among centers from 0 to 7.0 per 10 000 randomized men. A limitation of this study is that differences in procedures among centers decreased the comparability of the results.

Conclusions

Intervention-related deaths were rare in ERSPC. Monitoring of intervention-related deaths in screening trials is important for assessment of harms.

Patient summary

We investigated deaths due to screening or treatment to assess harm in a trial of prostate cancer screening. Few such deaths were identified.

Association of Race and Ethnicity With Prostate Cancer-Specific Mortality in Canada

This cohort study uses data from the Canadian Census Health and Environment Cohorts to assess the association of race and ethnicity with prostate cancer–specific mortality among men in Canada.

Unifying the death notification form: Recommendations by the Saudi Health Council task force

Objectives

Death reporting and certification forms are essential elements of a country's healthcare policies. KSA faces several challenges regarding death reporting and certification. This study aims to provide recommendations to unify death notifications in Saudi Arabia.

Methods

In 2019, the General Secretariat of the Saudi Health Council designed a qualitative research project that aimed to provide recommendations to unify death notifications. The council convened a task force of physicians and healthcare administrators to design and conduct qualitative research to review the Saudi Health Council's policies related to death certification and investigate potential methods of improvement. In addition, the task force performed an extensive review of the literature and current practices in KSA.

Results

The task force proposed a set of robust recommendations to correct the issues affecting the current systems of death reporting and certification.

Conclusions

This report presents the working methodology and recommendations of the task force.

Statin use and survival in 16 098 patients with non-Hodgkin lymphoma or chronic lymphocytic leukaemia treated in the rituximab era

Statin use has been associated with reduced mortality from several cancers but also suggested, in vitro, to diminish the effectiveness of lymphoma treatments including rituximab. The present study aimed to assess the association of statin use with mortality in patients with non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukaemia (CLL). We identified all incident NHLs and CLLs in Sweden from 2007 to 2013 with subtype information in the Swedish Lymphoma and Cancer Registers. Using Cox regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of pre- or post-diagnosis statin use (yes/no, intensity) with lymphoma-specific, cardiovascular, or all-cause mortality; and for follicular lymphoma (FL) by initial treatment strategy (active/watch-and-wait). Among 16 098 incident NHL/CLL patients, 20% used statins at diagnosis. Pre- and post-diagnosis statin use, and statin intensity were not consistently associated with any mortality outcome in patients with NHL, overall or for any subtype. For actively treated patients with FL, statin use did not appear to increase lymphoma-specific mortality (vs. non-users, HR [95% CI]_{after diagnosis} 0·87 [0·45-1·67]). For CLL, statin use was associated with all-cause and cardiovascular but not consistently with lymphoma-specific mortality. In conclusion, statin use was not associated with improved lymphoma survival but appears safe to use during lymphoma treatment.

Risk of esophageal and gastric adenocarcinoma in men receiving androgen deprivation therapy for prostate cancer

The aim of this study was to explore the male predominance in esophageal and gastric adenocarcinoma by evaluating the preventive potential of androgen deprivation therapy (ADT). This matched cohort study was based on a national Swedish database of prostate cancer patients in 2006-2013. Prostate cancer patients receiving ADT were the exposed group. Prostate cancer-free men from the general population were randomly selected and matched to the index case by birth year and county of residence, forming the unexposed control group. The participants were followed until a diagnosis of esophageal or gastric cancer, death, emigration, or end of the study period. The risk of esophageal adenocarcinoma, cardia gastric adenocarcinoma, non-cardia gastric adenocarcinoma, and esophageal squamous-cell carcinoma among ADT-exposed compared to unexposed was calculated by multivariable Cox proportional hazard regression. The hazard ratios (HRs) and 95% confidence intervals (CIs) were adjusted for confounders. There was a risk reduction of non-cardia gastric adenocarcinoma among ADT-users compared to non-users (HR 0.49 [95% CI 0.24-0.98]). No such decreased risk was found for esophageal adenocarcinoma (HR 1.17 [95% CI 0.60-2.32]), cardia gastric adenocarcinoma (HR 0.99 [95% CI 0.40-2.46]), or esophageal squamous cell carcinoma (HR 0.99 [95% CI 0.31-3.13]). This study indicates that androgen deprivation therapy decreases the risk of non-cardia gastric adenocarcinoma, while no decreased risk was found for esophageal adenocarcinoma, cardia gastric adenocarcinoma, or esophageal squamous-cell carcinoma.

Temporal changes in cause-specific death in men with localised prostate cancer treated with radical prostatectomy: a population-based, nationwide study

Background and Objective

Changes in diagnostic work‐up, histopathological assessment, and treatment of men with prostate cancer during the last 20 years have affected the prognosis. The objective was to investigate the risk of prostate cancer death in men with clinically localised prostate cancer treated with radical prostatectomy in Sweden in 2000–2010.

Methods

Population‐based, nationwide, study on men with clinically localised prostate cancer treated with radical prostatectomy in the period 2000–2010. Cox regression analyses were used to assess differences in risk of prostate cancer death according to calendar period for diagnosis and stratified on risk category.

Results

The study included 19 330 men with a median follow‐up of 12.4 years. Men diagnosed in 2007–2008 and 2009–2010 had a significantly lower risk of prostate cancer death compared to men diagnosed in 2000–2002. The reduced risk of prostate cancer death was restricted to men with intermediate‐risk prostate cancer with no differences observed in men with low‐ or high‐risk prostate cancer.

Conclusion

During the study period, the risk of prostate cancer death decreased in the total population of men with localised prostate cancer treated with radical prostatectomy. The decrease was restricted to men with intermediate‐risk prostate cancer.

Completeness and accuracy of national cancer and death registration for outcome ascertainment in trials-an ovarian cancer exemplar

BACKGROUND

There is a trend to increasing use of routinely collected health data to ascertain outcome measures in trials. We report on the completeness and accuracy of national ovarian cancer and death registration in the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).

METHODS

Of the 202,638 participants, 202,632 were successfully linked and followed through national cancer and death registries of Northern Ireland, Wales and England. Women with registrations of any of 19 pre-defined ICD-10 codes suggestive of tubo-ovarian cancer or notification of ovarian/tubal/peritoneal cancer from hospital episode statistics or trial sites were identified. Copies of hospital and primary care notes were retrieved and reviewed by an independent outcomes review committee. National registration of site and cause of death as ovarian/tubal/peritoneal cancer (C56/C57/C48) obtained up to 3 months after trial censorship was compared to that assigned by outcomes review (reference standard).

RESULTS

Outcome review was undertaken in 3110 women on whom notification was received between 2001 and 2014. Ovarian cancer was confirmed in 1324 of whom 1125 had a relevant cancer registration. Sensitivity and specificity of ovarian/tubal/peritoneal cancer registration were 85.0% (1125/1324; 95% CI 83.7-86.2%) and 94.0% (1679/1786; 95% CI 93.2-94.8%), respectively. Of 2041 death registrations reviewed, 681 were confirmed to have a tubo-ovarian cancer of whom 605 had relevant death registration. Sensitivity and specificity were 88.8% (605/681; 95% CI 86.4-91.2%) and 96.7% (1482/1533, 95% CI 95.8-97.6%), respectively. When multiple electronic health record sources were considered, sensitivity for cancer site increased to 91.1% (1206/1324, 95% CI 89.4-92.5%) and for cause of death 94.0% (640/681, 95% CI 91.9-95.5%). Of 1232 with cancer registration, 8.7% (107/1232) were wrongly designated as ovarian/tubal/peritoneal cancers by the registry and 4.0% (47/1172) of confirmed tubo-ovarian cancers were mis-registered. In 656 with death registrations, 7.8% (51/656) were wrongly assigned as due to ovarian/tubal/peritoneal cancers while 6.2% (40/645) of confirmed tubo-ovarian cancer deaths were mis-registered.

CONCLUSION

Follow-up of trial participants for tubo-ovarian cancer using national registry data will result in incomplete ascertainment, particularly of the site due in part to the latency of registration. This can be reduced by using other routinely collected data such as hospital episode statistics. Central adjudication by experts though resource intensive adds value by improving the accuracy of diagnoses.

TRIAL REGISTRATION

ISRCTN: ISRCTN22488978 . Registered on 6 April 2000.

Simulation model of disease incidence driven by diagnostic activity

It is imperative to understand the effects of early detection and treatment of chronic diseases, such as prostate cancer, regarding incidence, overtreatment and mortality. Previous simulation models have emulated clinical trials, and relied on extensive assumptions on the natural history of the disease. In addition, model parameters were typically calibrated to a variety of data sources. We propose a model designed to emulate real‐life scenarios of chronic disease using a proxy for the diagnostic activity without explicitly modeling the natural history of the disease and properties of clinical tests. Our model was applied to Swedish nation‐wide population‐based prostate cancer data, and demonstrated good performance in terms of reconstructing observed incidence and mortality. The model was used to predict the number of prostate cancer diagnoses with a high or limited diagnostic activity between 2017 and 2060. In the long term, high diagnostic activity resulted in a substantial increase in the number of men diagnosed with lower risk disease, fewer men with metastatic disease, and decreased prostate cancer mortality. The model can be used for prediction of outcome, to guide decision‐making, and to evaluate diagnostic activity in real‐life settings with respect to overdiagnosis and prostate cancer mortality.

Statin use is associated with improved survival in multiple myeloma: A Swedish population-based study of 4315 patients

Statin use has been associated with reduced cancer-specific mortality among patients with several cancer types, including multiple myeloma (MM). We aimed to further elucidate the association of statin use and dose intensity with MM survival. Using Swedish population-based national health registers, we identified all incident MM diagnoses occurring January 1, 2007 to December 31, 2013 and their drug dispensations and comorbidities. We assessed statin exposure in 6-month periods pre- and post-diagnosis, treated diagnosis as baseline for calculating survival time, and calculated hazard ratios (HR) and 95% confidence intervals (CI) of exposure-related MM-specific and all-cause mortality using Cox regression. We assessed statin exposure during the entire follow-up and risk of MM-specific mortality in a nested case-control analysis. We classified dose intensity according to American College of Cardiology/American Heart Association recommendations. We ascertained 4315 MM cases during follow-up. Statin use was associated with reduced MM-specific mortality (pre-diagnosis use multivariate-adjusted HR, 95% CI: 0.83, 0.71-0.96; 6 months post-diagnosis: 0.73, 0.60-0.89; entire follow-up: 0.65, 0.52-0.80) and (more weakly) with all-cause mortality. Intensity analyses suggested a dose-response; MM-specific mortality decreased with increasing statin intensity in all time windows (eg, 6 months post-diagnosis: low [0.76 (0.56-1.03)], medium [0.73 (0.58-0.92)], high [0.33 (0.08-1.32)] intensity). However, relatively few patients received high intensity treatment, and the trend was statistically significant only for unadjusted pre-diagnosis use. In this large population-based MM cohort, statin use was associated with improved MM-specific survival in both sexes. Randomized prospective studies are warranted to evaluate statins as adjuvant treatment in MM.

Estimation of Relative and Absolute Risks in a Competing-Risks Setting Using a Nested Case-Control Study Design: Example From the ProMort Study

In this paper, we describe the Prognostic Factors for Mortality in Prostate Cancer (ProMort) study and use it to demonstrate how the weighted likelihood method can be used in nested case-control studies to estimate both relative and absolute risks in the competing-risks setting. ProMort is a case-control study nested within the National Prostate Cancer Register (NPCR) of Sweden, comprising 1,710 men diagnosed with low- or intermediate-risk prostate cancer between 1998 and 2011 who died from prostate cancer (cases) and 1,710 matched controls. Cause-specific hazard ratios and cumulative incidence functions (CIFs) for prostate cancer death were estimated in ProMort using weighted flexible parametric models and compared with the corresponding estimates from the NPCR cohort. We further drew 1,500 random nested case-control subsamples of the NPCR cohort and quantified the bias in the hazard ratio and CIF estimates. Finally, we compared the ProMort estimates with those obtained by augmenting competing-risks cases and by augmenting both competing-risks cases and controls. The hazard ratios for prostate cancer death estimated in ProMort were comparable to those in the NPCR. The hazard ratios for dying from other causes were biased, which introduced bias in the CIFs estimated in the competing-risks setting. When augmenting both competing-risks cases and controls, the bias was reduced.

Causes of death in men with prostate cancer: Results from the Danish Prostate Cancer Registry (DAPROCAdata)

BACKGROUND

Current knowledge of the validity of registry data on prostate cancer-specific death is limited. We aimed to determine the underlying cause of death among Danish men with prostate cancer, to estimate the level of misattribution of prostate cancer death, and to examine the risk of death from prostate cancer when accounting for competing risk of death.

MATERIAL AND METHODS

We investigated a nationwide cohort of 15,878 prostate cancer patients diagnosed in 2010-2014; with 3343 deaths occurring through 2016. Blinded medical chart review was carried out for 670 deaths and compared to the national cause of death registry. Five death categories were defined: 1) prostate cancer-specific death, 2) other unspecified urological cancer death, 3) other cancer death 4) cardiovascular disease death, and 5) other causes of death. Competing risk analyses compared Cox cause-specific and Fine-Gray regression models.

RESULTS

Chart review attributed 51.2% of deaths to prostate cancer, 17.0% to cardiovascular disease, and 16.7% to other causes. The Danish Register of Causes of Death attributed 71.7% of deaths to prostate cancer when including all registered contributing causes of death, and 57.0% of deaths when including only the primary registered cause of death. The probability of death by prostate cancer was 10% at 2-year survival.

CONCLUSIONS

More than half of the deceased men in our study cohort died of their prostate cancer disease within a mean of 2.4 years of follow up. Data from the death registry is prone to misclassification, potentially overestimating the proportion of deaths from prostate cancer.

SPCG-15: a prospective randomized study comparing primary radical prostatectomy and primary radiotherapy plus androgen deprivation therapy for locally advanced prostate cancer

OBJECTIVE

To describe study design and procedures for a prospective randomized trial investigating whether radical prostatectomy (RP) ± radiation improves cause-specific survival in comparison with primary radiation treatment (RT) and androgen deprivation treatment (ADT) in patients with locally advanced prostate cancer (LAPC).

MATERIALS AND METHODS

SPCG-15 is a prospective, multi-centre, open randomized phase III trial. Patients are randomized to either standard (RT + ADT) or experimental (RP with extended pelvic lymph-node dissection and with addition of adjuvant or salvage RT and/or ADT if deemed necessary) treatment. Each centre follows guidelines regarding the timing and dosing of postoperative RT and adjuvant treatment such as ADT The primary endpoint is cause-specific survival. Secondary endpoints include metastasis-free and overall survival, quality-of-life, functional outcomes and health-services requirements. Each subject will be followed up for a minimum of 10 years.

RESULTS

Twenty-three centres in Denmark, Finland, Norway and Sweden, well established in performing RP and RT for prostate cancer participated. Each country's sites were coordinated by national coordinating investigators and sub-investigators for urology and oncology. Almost 400 men have been randomized of the stipulated 1200, with an increasing rate of accrual.

CONCLUSIONS

The SPCG-15 trial aims to compare the two curatively intended techniques supplying new knowledge to support future decisions in treatment strategies for patients with LAPC The Scandinavian healthcare context is well suited for performing multi-centre long-term prospective randomized clinical trials. Similar care protocols and a history of entirely tax-funded healthcare facilitate joint trials.

Association Between Laparoscopic Antireflux Surgery and Recurrence of Gastroesophageal Reflux

IMPORTANCE

Cohort studies, mainly based on questionnaires and interviews, have reported high rates of reflux recurrence after antireflux surgery, which may have contributed to a decline in its use. Reflux recurrence after laparoscopic antireflux surgery has not been assessed in a long-term population-based study of unselected patients.

OBJECTIVES

To determine the risk of reflux recurrence after laparoscopic antireflux surgery and to identify risk factors for recurrence.

DESIGN AND SETTING

Nationwide population-based retrospective cohort study in Sweden between January 1, 2005, and December 31, 2014, based on all Swedish health care and including 2655 patients who underwent laparoscopic antireflux surgery according to the Swedish Patient Registry. Their records were linked to the Swedish Causes of Death Registry and Prescribed Drug Registry.

EXPOSURES

Primary laparoscopic antireflux surgery due to gastroesophageal reflux disease in adults (>18 years).

MAIN OUTCOMES AND MEASURES

The outcome was recurrence of reflux, defined as use of antireflux medication (proton pump inhibitors or histamine2 receptor antagonists for >6 months) or secondary antireflux surgery. Multivariable Cox regression was used to assess risk factors for reflux recurrence.

RESULTS

Among all 2655 patients who underwent antireflux surgery (median age, 51.0 years; interquartile range, 40.0-61.0 years; 1354 men [51.0%]) and were followed up for a median of 5.6 years, 470 patients (17.7%) had reflux recurrence; 393 (83.6%) received long-term antireflux medication and 77 (16.4%) underwent secondary antireflux surgery. Risk factors for reflux recurrence included female sex (hazard ratio [HR], 1.57 [95% CI, 1.29-1.90]; 286 of 1301 women [22.0%] and 184 of 1354 men [13.6%] had recurrence of reflux), older age (HR, 1.41 [95% CI, 1.10-1.81] for age ≥61 years compared with ≤45 years; recurrence among 156 of 715 patients and 133 of 989 patients, respectively), and comorbidity (HR, 1.36 [95% CI, 1.13-1.65] for Charlson comorbidity index score ≥1 compared with 0; recurrence among 180 of 804 patients and 290 of 1851 patients, respectively). Hospital volume of antireflux surgery was not associated with risk of reflux recurrence (HR, 1.09 [95% CI, 0.77-1.53] for hospital volume ≤24 surgeries compared with ≥76 surgeries; recurrence among 38 of 266 patients [14.3%] and 271 of 1526 patients [17.8%], respectively).

CONCLUSIONS AND RELEVANCE

Among patients who underwent primary laparoscopic antireflux surgery, 17.7% experienced recurrent gastroesophageal reflux requiring long-term medication use or secondary antireflux surgery. Risk factors for recurrence were older age, female sex, and comorbidity. Laparoscopic antireflux surgery was associated with a relatively high rate of recurrent gastroesophageal reflux disease requiring treatment, diminishing some of the benefits of the operation.

Gonadotropin-releasing Hormone Agonists, Orchiectomy, and Risk of Cardiovascular Disease: Semi-ecologic, Nationwide, Population-based Study

BACKGROUND

In observational studies, men with prostate cancer treated with gonadotropin-releasing hormone (GnRH) agonists had a higher risk of cardiovascular disease (CVD) compared to men who had undergone orchiectomy. However, selection bias may have influenced the difference in risk.

OBJECTIVE

To investigate the association of type of androgen deprivation therapy (ADT) with risk of CVD while minimising selection bias.

DESIGN, SETTING, AND PARTICIPANTS

Semi-ecologic study of 6556 men who received GnRH agonists and 3330 men who underwent orchiectomy as primary treatment during 1992-1999 in the Prostate Cancer Database Sweden 3.0.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We measured the proportion of men who received GnRH agonists as primary treatment in 580 experimental units defined by healthcare provider, diagnostic time period, and age at diagnosis. Incident or fatal CVD events in units with high and units with low use of GnRH agonists were compared. Net and crude probabilities were also analysed.

RESULTS AND LIMITATIONS

The risk of CVD was similar between units with the highest and units with the lowest proportion of GnRH agonist use (relative risk 1.01, 95% confidence interval [CI] 0.93-1.11). Accordingly, there was no difference in the net probability of CVD after GnRH agonist compared to orchiectomy (hazard ratio 1.02, 95% CI 0.96-1.09). The 10-yr crude probability of CVD was 0.56 (95% CI 0.55-0.57) for men on GnRH agonists and 0.52 (95% CI 0.50-0.54) for men treated with orchiectomy. The main limitation was the nonrandom allocation to treatment, with younger men with lower comorbidity and less advanced cancer more likely to receive GnRH agonists.

CONCLUSION

Our data do not support previous observations that GnRH agonists increase the risk of CVD in comparison to orchiectomy.

PATIENT SUMMARY

We found a similar risk of cardiovascular disease between medical and surgical treatment as androgen deprivation therapy for prostate cancer.

Snus use, smoking and survival among prostate cancer patients

Smoking is associated with prostate cancer mortality. The Scandinavian smokeless tobacco product snus is a source of nicotine but not the combustion products of smoke and has not been studied with respect to prostate cancer survival. The study is nested among 9,582 men with incident prostate cancer within a prospective cohort of 336,381 Swedish construction workers. Information on tobacco use was collected at study entry between 1971 and 1992, and categorized into (i) never users of any tobacco, (ii) exclusive snus: ever users of snus only, (iii) exclusive smokers: ever smokers (cigarette, cigar and/or pipe) only and (iv) ever users of both snus and smoking. Hazard ratios for prostate cancer-specific and total mortality for smoking and snus use based on Cox proportional hazards models adjusted for age, calendar period at diagnosis and body mass index at baseline. During 36 years of follow-up, 4,758 patients died-2,489 due to prostate cancer. Compared to never users of tobacco, exclusive smokers were at increased risk of prostate cancer mortality (HR 1.15, 95% CI: 1.05-1.27) and total mortality (HR 1.17, 95% CI: 1.09-1.26). Exclusive snus users also had increased risks for prostate cancer mortality (HR 1.24, 95% CI: 1.03-1.49) and total mortality (HR 1.19, 95% CI: 1.04-1.37). Among men diagnosed with nonmetastatic disease, the HR for prostate cancer death among exclusive snus users was 3.17 (95% CI: 1.66-6.06). The study is limited by a single assessment of tobacco use prior to diagnosis. Snus use was associated with increased risks of prostate cancer and total mortality among prostate cancer patients. This suggests that tobacco-related components such as nicotine or tobacco-specific carcinogens may promote cancer progression independent of tobacco's combustion products.

Impact of cause of death adjudication on the results of the European prostate cancer screening trial

BACKGROUND

The European Randomised Study of Prostate Cancer Screening has shown a 21% relative reduction in prostate cancer mortality at 13 years. The causes of death can be misattributed, particularly in elderly men with multiple comorbidities, and therefore accurate assessment of the underlying cause of death is crucial for valid results. To address potential unreliability of end-point assessment, and its possible impact on mortality results, we analysed the study outcome adjudication data in six countries.

METHODS

Latent class statistical models were formulated to compare the accuracy of individual adjudicators, and to assess whether accuracy differed between the trial arms. We used the model to assess whether correcting for adjudication inaccuracies might modify the study results.

RESULTS

There was some heterogeneity in adjudication accuracy of causes of death, but no consistent differential accuracy by trial arm. Correcting the estimated screening effect for misclassification did not alter the estimated mortality effect of screening.

CONCLUSIONS

Our findings were consistent with earlier reports on the European screening trial. Observer variation, while demonstrably present, is unlikely to have materially biased the main study results. A bias in assigning causes of death that might have explained the mortality reduction by screening can be effectively ruled out.

Proportion and characteristics of men with unknown risk category in the National Prostate Cancer Register of Sweden

BACKGROUND

Knowledge on missing data in a clinical cancer register is important to assess the validity of research results. For analysis of prostate cancer (Pca), risk category, a composite variable based on serum levels of prostate specific antigen (PSA), stage, and Gleason score, is crucial for treatment decisions and a strong determinant of outcome. The aim of this study was to assess the proportion and characteristics of men in the National Prostate Cancer Register (NPCR) of Sweden with unknown risk category.

MATERIAL AND METHODS

Men diagnosed with Pca between 1998 and 2012 registered in NPCR with known or unknown risk category were compared with respect to age, socioeconomic factors, comorbidity, cancer characteristics, cancer treatment, and mortality from Pca and other causes.

RESULTS

In total, 3315 of 129 391 (3%) men had unknown risk category. Compared to other men in NPCR, these men more often had a concomitant bladder cancer diagnosis, 19% versus 1%, diagnosis of benign prostatic hyperplasia 31% versus 5%, received unspecified Pca treatment 16% versus 3%, had higher comorbidity, Charlson Comorbidity Index 2 or higher, 34% versus 13%, and had lower Pca mortality 12% versus 30%, but similar mortality from other causes.

CONCLUSION

Men with unknown risk category were rare in NPCR but distinctly different from other men in NPCR in many aspects including higher comorbidity and lower Pca mortality.

Contemporary accuracy of death certificates for coding prostate cancer as a cause of death: Is reliance on death certification good enough? A comparison with blinded review by an independent cause of death evaluation committee

BACKGROUND

Accurate cause of death assignment is crucial for prostate cancer epidemiology and trials reporting prostate cancer-specific mortality outcomes.

METHODS

We compared death certificate information with independent cause of death evaluation by an expert committee within a prostate cancer trial (2002-2015).

RESULTS

Of 1236 deaths assessed, expert committee evaluation attributed 523 (42%) to prostate cancer, agreeing with death certificate cause of death in 1134 cases (92%, 95% CI: 90%, 93%). The sensitivity of death certificates in identifying prostate cancer deaths as classified by the committee was 91% (95% CI: 89%, 94%); specificity was 92% (95% CI: 90%, 94%). Sensitivity and specificity were lower where death occurred within 1 year of diagnosis, and where there was another primary cancer diagnosis.

CONCLUSIONS

UK death certificates accurately identify cause of death in men with prostate cancer, supporting their use in routine statistics. Possible differential misattribution by trial arm supports independent evaluation in randomised trials.

Screening for Prostate Cancer Starting at Age 50-54 Years. A Population-based Cohort Study

BACKGROUND

Current prostate cancer screening guidelines conflict with respect to the age at which to initiate screening.

OBJECTIVE

To evaluate the effect of prostate-specific antigen (PSA) screening versus zero screening, starting at age 50-54 yr, on prostate cancer mortality.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based cohort study comparing 3479 men aged 50 yr through 54 yr randomized to PSA-screening in the Göteborg population-based prostate cancer screening trial, initiated in 1995, versus 4060 unscreened men aged 51-55 yr providing cryopreserved blood in the population-based Malmö Preventive Project in the pre-PSA era, during 1982-1985.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cumulative incidence and incidence rate ratios of prostate cancer diagnosis, metastasis, and prostate cancer death.

RESULTS AND LIMITATIONS

At 17 yr, regular PSA-screening in Göteborg of men in their early 50s carried a more than two-fold higher risk of prostate cancer diagnosis compared with the unscreened men in Malmö (incidence rate ratio [IRR] 2.56, 95% confidence interval [CI] 2.18, 3.02), but resulted in a substantial decrease in the risk of metastases (IRR 0.43, 95% CI 0.22, 0.79) and prostate cancer death (IRR 0.29, 95% CI 0.11, 0.67). There were 57 fewer prostate cancer deaths per 10000 men (95% CI 22, 92) in the screened group. At 17 yr, the number needed to invite to PSA-screening and the number needed to diagnose to prevent one prostate cancer death was 176 and 16, respectively. The study is limited by lack of treatment information and the comparison of the two different birth cohorts.

CONCLUSIONS

PSA screening for prostate cancer can decrease prostate cancer mortality among men aged 50-54 yr, with the number needed to invite and number needed to detect to prevent one prostate cancer death comparable to those previously reported from the European Randomized Study of Screening for Prostate Cancer for men aged 55-69 yr, at a similar follow-up. Guideline groups could consider whether guidelines for PSA screening should recommend starting no later than at ages 50-54 yr.

PATIENT SUMMARY

Guideline recommendations about the age to start prostate-specific antigen screening could be discussed.

Causes of death in men with localized prostate cancer: a nationwide, population-based study

OBJECTIVE

To detail the distribution of causes of death from localized prostate cancer (PCa).

PATIENTS AND METHODS

The database PCBase Sweden links the Swedish National Prostate Cancer Register with other nationwide population-based healthcare registers. We selected all 57 187 men diagnosed with localized PCa between 1997 and 2009 and their 114 374 PCa-free control subjects, matched according to age and county of residence. Mortality was calculated using competing risk regression analyses, taking into account PCa risk category, age and Charlson comorbidity index (CCI).

RESULTS

In men with low-risk PCa, all-cause mortality was lower compared with that in corresponding PCa-free men: 10-year all-cause mortality was 18% for men diagnosed at age 70 years, with a CCI score of 0, and 21% among corresponding control subjects. Of these cases, 31% died from cardiovascular disease (CVD) compared with 37% of the corresponding control subjects. For men with low-risk PCa, 10-year PCa-mortality was 0.4, 1 and 3% when diagnosed at age 50, 60 and 70 years, respectively. PCa was the third most common cause of death (18%), after CVD (31%) and other cancers (30%). By contrast, PCa was the most common cause of death in men with intermediate- and high-risk localized PCa.

CONCLUSIONS

Men with low-risk PCa had lower all-cause mortality than PCa-free men because of lower CVD mortality, driven by early detection selection; however, for men with intermediate- or high-risk disease, the rate of PCa death was substantial, irrespective of CCI score, and this was even more pronounced for those diagnosed at age 50 or 60 years.

Capture rate and representativity of The National Prostate Cancer Register of Sweden

BACKGROUND

Capture rate and representativity of quality registers need to be assessed in order to ensure that register data are generalizable.

MATERIAL AND METHODS

In 1998-2009, 103 047 men had been diagnosed with prostate cancer and registered in the Swedish Cancer Register to which registration is mandated by law and of these men, 100 849 men (98%) had also been registered in The National Prostate Cancer Register (NPCR) of Sweden. We compared demographics, cancer treatment, comorbidity, and mortality in men in NPCR, with those who had only been registered in the Cancer Register, by use of data from the Cause of Death Register, the In-Patient Register and the Prescribed Drug Register. In addition, we identified 1929 men who had prostate cancer as underlying cause of death in the Cause of Death Register who had neither been registered in the Cancer Register nor in NPCR.

RESULTS

Compared to men in NPCR, men only registered in the Cancer Register were slightly older, median age 72 versus 71 years, and a lower proportion underwent radical prostatectomy, 15% versus 27%. Ten year prostate cancer mortality was 23% (95% CI 20-25) for men in the Cancer Register only and 24% (95% CI 24-25) in NPCR, while mortality from competing causes was 28% (95% CI 26-31) and 30% (95% CI 30-30), respectively. Men identified with prostate cancer by a death certificate were old and had high comorbidity.

CONCLUSION

The capture rate of NPCR is very high and there are only modest differences in demographics, cancer treatment, comorbidity, and mortality between the small proportion of men only registered in the Cancer Register and men registered in NPCR, indicating that information in NPCR can be generalized to all men with prostate cancer in Sweden.

Opportunistic testing versus organized prostate-specific antigen screening: outcome after 18 years in the Göteborg randomized population-based prostate cancer screening trial

BACKGROUND

It has been shown that organized screening decreases prostate cancer (PC) mortality, but the effect of opportunistic screening is largely unknown.

OBJECTIVE

To compare the ability to reduce PC mortality and the risk of overdiagnosis between organized and opportunistic screening.

DESIGN, SETTING, AND PARTICIPANTS

The Göteborg screening study invited 10 000 randomly selected men for prostate-specific antigen (PSA) testing every 2 yr since 1995, with a prostate biopsy recommended for men with PSA ≥2.5 ng/ml. The control group of 10 000 men not invited has been exposed to a previously reported increased rate of opportunistic PSA testing. Both groups were followed until December 31, 2012.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Observed cumulative PC incidence and mortality rates in both groups were calculated using the actuarial method. Using historical data from 1990-1994 (pre-PSA era), we calculated expected PC incidence and mortality rates in the absence of any PSA testing. The number needed to invite (NNI) and the number needed to diagnose (NND) were calculated by comparing the expected versus observed incidence and mortality rates.

RESULTS AND LIMITATIONS

At 18 yr, 1396 men were diagnosed with PC and 79 men died of PC in the screening group, compared to 962 and 122, respectively, in the control group. In the screening group, the observed cumulative PC incidence/mortality was 16%/0.98% compared to expected values of 6.8%/1.7%. The corresponding values for the control group were 11%/1.5% and 6.9%/1.7%. Organized screening was associated with an absolute PC-specific mortality reduction of 0.72% (95% confidence interval [CI] 0.50-0.94%) and relative risk reduction of 42% (95% CI 28-54%). There was an absolute reduction in PC deaths of 0.20% (95% CI -0.06% to 0.47%) and a relative risk reduction of 12% (95% CI -5 to 26%) associated with opportunistic PSA testing. NNI and NND were 139 (95% CI 107-200) and 13 for organized biennial screening and 493 (95% CI 213- -1563) and 23 for opportunistic screening. The extent of opportunistic screening could not be measured; incidence trends were used as a proxy.

CONCLUSIONS

Organized screening reduces PC mortality but is associated with overdiagnosis. Opportunistic PSA testing had little if any effect on PC mortality and resulted in more overdiagnosis, with almost twice the number of men needed to be diagnosed to save one man from dying from PC compared to men offered an organized biennial screening program.

PATIENT SUMMARY

Prostate-specific antigen (PSA) screening within the framework of an organized program seems more effective than unorganized screening.

Systematic underreporting of the population-based incidence of pancreatic and biliary tract cancers

BACKGROUND

Incidence rates of cancers of the pancreas and biliary tract, typically derived from cancer registers, have been reported to be decreasing. This study tested whether pancreatic and biliary tract cancers are underreported in the Swedish Cancer Register (CR).

METHODS

The concordance of pancreatic and biliary tract cancer diagnoses in 1990-2009 between CR and the Swedish Patient Register (PR) were evaluated through record linkage. To further assess the completeness of these cancer diagnoses in both CR and PR, record linkage was also made to the Swedish Causes of Death Register (DR).

RESULTS

A total of 31 067 cases of pancreatic cancer and 14 273 cases of biliary tract cancer were identified in CR or PR. Altogether, 44% of the pancreatic cancers and 44% of the biliary tract cancers were registered in PR only, and not in CR. The concordance between CR and PR declined from 63% in the years 1990-1994 to 44% in 2005-2009 for pancreatic cancer. The corresponding figures for biliary tract cancer were 60% and 37%. This decline in concordance was also observed with increasing age, e.g. the concordance between CR and PR for pancreatic cancer declined from 62% in patients<60 years to 36% among patients≥80 years. The corresponding figures for biliary tract cancer were 52% and 38%.

CONCLUSION

There is an overwhelming underreporting of pancreatic and biliary tract cancers within the Swedish Cancer Register, which has increased during recent years. The reported decreasing incidence rates for pancreatic and biliary tract cancers might therefore be incorrect.

Prostate cancer mortality in areas with high and low prostate cancer incidence

Background

The effect of prostate-specific antigen (PSA) screening on prostate cancer mortality remains debated, despite evidence from randomized trials. We investigated the association between prostate cancer incidence, reflecting uptake of PSA testing, and prostate cancer mortality.

Methods

The study population consisted of all men aged 50 to 74 years residing in eight counties in Sweden with an early increase in prostate cancer incidence and six counties with a late increase during two time periods. Incidence of metastatic prostate cancer was investigated in the period from 2000 to 2009, and prostate cancer–specific mortality and excess mortality were investigated in the period from 1990 to 1999 and the period from 2000 to 2009 by calculating rate ratios for high- vs low-incidence counties and rate ratios for the period from 2000 to 2009 vs the period from 1990 to 1999 within these two groups. All statistical tests were two-sided.

Results

There were 4528134 person-years at risk, 1577 deaths from prostate cancer, and 1210 excess deaths in men with prostate cancer in high-incidence counties and 2471373 person-years at risk, 985 prostate cancer deaths, and 878 excess deaths in low-incidence counties in the period from 2000 to 2009. Rate ratios in counties with high vs low incidence adjusted for time period were 0.81 (95% confidence interval [CI] = 0.73 to 0.90) for prostate cancer– specific mortality and 0.74 (95% CI = 0.64 to 0.86) for excess mortality, and the rate ratio of metastatic prostate cancer was 0.85 (95% CI = 0.79 to 0.92).

Conclusions

The lower prostate cancer mortality in high-incidence counties reflecting a high PSA uptake suggests that more-intense as compared with less-intense opportunistic PSA screening reduces prostate cancer mortality.

Population-based study on use of chemotherapy in men with castration resistant prostate cancer

BACKGROUND

Chemotherapy prolongs life and relieves symptoms in men with castration resistant prostate cancer (CRPC). There is limited information on a population level on the use of chemotherapy for CRPC.

MATERIAL AND METHODS

To assess the use of chemotherapy in men with CRPC we conducted a register-based nationwide population-based study in Prostate Cancer data Base Sweden (PCBaSe) and a nationwide in-patient drug register (SALT database) between May 2009 and December 2010. We assumed that men who died of prostate cancer (PCa) underwent a period of CRPC before they died.

RESULTS

Among the 2677 men who died from PCa during the study inclusion period, 556 (21%) had received chemotherapy (intravenous or per oral) detectable within the observation period in SALT database. Specifically, 239 (61%) of men < 70 years had received chemotherapy, 246 (30%) of men between 70 and 79 years and 71 (5%) men older than 80 years. The majority of men 465/556 (84%) had received a docetaxel-containing regimen. Among chemotherapy treated men, 283/556 (51%) received their last dose of chemotherapy during the last six months prior to death. Treatment with chemotherapy was more common among men with little comorbidity and high educational level, as well as in men who had received curatively intended primary treatment.

CONCLUSION

A majority of men younger than 70 years with CRPC were treated with chemotherapy in contrast to men between 70 and 79 years of whom half as many received chemotherapy. Chemotherapy treatment was often administered shortly prior to death. The low uptake of chemotherapy in older men with CRPC may be caused by concerns about tolerability of treatment, as well as treatment decisions based on chronological age rather than global health status.

Increasing use of radical prostatectomy for nonlethal prostate cancer in Sweden

PURPOSE

The number of patients in Sweden treated with radical prostatectomy for localized prostate cancer has increased exponentially. The extent to which this increase reflects treatment of nonlethal disease detected through prostate-specific antigen (PSA) screening is unknown.

EXPERIMENTAL DESIGN

We undertook a nationwide study of all 18,837 patients with prostate cancer treated with radical prostatectomy in Sweden from 1988 to 2008 with complete follow-up through 2009. We compared cumulative incidence curves, fit Cox regression and cure models, and conducted a simulation study to determine changes in treatment of nonlethal cancer, in cancer-specific survival over time, and effect of lead-time due to PSA screening.

RESULTS

The annual number of radical prostatectomies increased 25-fold during the study period. The 5-year cancer-specific mortality rate decreased from 3.9% [95% confidence interval (CI), 2.5-5.3] among patients diagnosed between 1988 and 1992 to 0.7% (95% CI, 0.4-1.1) among those diagnosed between 1998 and 2002 (P(trend) < 0.001). According to the cure model, the risk of not being cured declined by 13% (95% CI, 12%-14%) with each calendar year. The simulation study indicated that only about half of the improvement in disease-specific survival could be accounted for by lead-time.

CONCLUSION

Patients overdiagnosed with nonlethal prostate cancer appear to account for a substantial and growing part of the dramatic increase in radical prostatectomies in Sweden, but increasing survival rates are likely also due to true reductions in the risk of disease-specific death over time. Because the magnitude of harm and costs due to overtreatment can be considerable, identification of men who likely benefit from radical prostatectomy is urgently needed.

Long-term outcomes among noncuratively treated men according to prostate cancer risk category in a nationwide, population-based study

BACKGROUND

Limited data exist on long-term outcomes among men with prostate cancer (PCa) from population-based cohorts incorporating information on clinical risk category.

OBJECTIVE

To assess 15-yr mortality for men with PCa treated with noncurative intent according to clinical stage, Gleason score (GS), serum levels of prostate specific antigen (PSA), comorbidity, and age.

DESIGN, SETTING, AND PARTICIPANTS

Register-based cohort study of 76 437 cases in the National Prostate Cancer Register (NPCR) of Sweden diagnosed from 1991 through 2009 and treated with noncurative intent. Each case was placed in one of five risk categories: (1) low risk: T1-T2 tumor, PSA level <10 ng/ml, and GS ≤6; (2) intermediate risk: T1-T2 tumor and PSA level 10-<20 ng/ml or GS 7; (3) high risk: T3 tumor or PSA level 20-<50 ng/ml or GS ≥8; (4) regional metastases: N1 or T4 tumor or PSA level 50-100 ng/ml; and (5) distant metastases: M1 tumor or PSA ≥100 ng/ml.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Ten- and 15-yr cumulative risk of death after diagnosis from PCa, cardiovascular disease, and other causes.

RESULTS AND LIMITATIONS

Among men with a Charlson Comorbidity Index (CCI) score of 0, no differences were found in observed versus expected all-cause mortality in the low-risk group. Observed mortality was only slightly greater in the intermediate-risk group, but men with high-risk localized PCa or more advanced disease had substantially higher mortality than expected. CCI was strongly associated with cumulative 10-yr mortality from causes other than PCa, especially for men <65 yr. Limitations include potential misclassification in risk category due to GS assignment.

CONCLUSIONS

PCa mortality rates vary 10-fold according to risk category. The risk of death from causes other than PCa is most strongly related to comorbidity status in younger men.

Cohort Profile: the National Prostate Cancer Register of Sweden and Prostate Cancer data Base Sweden 2.0

In 1987, the first Regional Prostate Cancer Register was set up in the South-East health-care region of Sweden. Other health-care regions joined and since 1998 virtually all prostate cancer (PCa) cases are registered in the National Prostate Cancer Register (NPCR) of Sweden to provide data for quality assurance, bench marking and clinical research. NPCR includes data on tumour stage, Gleason score, serum level of prostate-specific antigen (PSA) and primary treatment. In 2008, the NPCR was linked to a number of other population-based registers by use of the personal identity number. This database named Prostate Cancer data Base Sweden (PCBaSe) has now been extended with more cases, longer follow-up and a selection of two control series of men free of PCa at the time of sampling, as well as information on brothers of men diagnosed with PCa, resulting in PCBaSe 2.0. This extension allows for studies with case-control, cohort or longitudinal case-only design on aetiological factors, pharmaceutical prescriptions and assessment of long-term outcomes. The NPCR covers >96% of all incident PCa cases registered by the Swedish Cancer Register, which has an underreporting of <3.7%. The NPCR is used to assess trends in incidence, treatment and outcome of men with PCa. Since the national registers linked to PCBaSe are complete, studies from PCBaSe 2.0 are truly population based.