Cancer surveillance series: interpreting trends in prostate cancer--part II: Cause of death misclassification and the recent rise and fall in prostate cancer mortality

Racial disparities in prostate cancer mortality: a model-based decomposition of contributing factors

To investigate the relative contributions of natural history and clinical interventions to racial disparities in prostate cancer mortality in the United States, we extended a model that was previously calibrated to Surveillance, Epidemiology, and End Results (SEER) incidence rates for the general population and for Black men. The extended model integrated SEER data on curative treatment frequencies and cancer-specific survival. Starting with the model for all men, we replaced up to 9 components with corresponding components for Black men, projecting age-standardized mortality rates for ages 40-84 years at each step. Based on projections in 2019, the increased frequency of developing disease, more aggressive tumor features, and worse cancer-specific survival in Black men diagnosed at local-regional and distant stages explained 38%, 34%, 22%, and 8% of the modeled disparity in mortality. Our results point to intensified screening and improved care in Black men as priority areas to achieve greater equity.

Global burden of prostate cancer attributable to smoking among males in 204 countries and territories, 1990-2019

INTRODUCTION

Understanding the latest global spatio-temporal pattern of prostate cancer burden attributable to smoking can help guide effective global health policy. This study aims to elucidate the trends in smoking-related prostate cancer from 1990 to 2019 using Global Burden of Disease (GBD) 2019 study data.

METHODS

Data on prostate cancer attributable to smoking were extracted from Global Burden of Disease Study (GBD) 2019. The numbers and age-standardized rates on smoking-related prostate cancer mortality (ASMR) and disability-adjusted life years (ASDR) were analyzed by year, age, region, country, and socio-demographic index (SDI) level. Estimated annual percentage change (EAPC) was calculated to evaluate the temporal trends of ASMR and ASDR from 1990 to 2019.

RESULTS

Of all prostate cancer deaths and DALYs globally in 2019, 6% and 6.6% were attributable to smoking, which contributed to 29,298 (95% CI 12,789 to 46,609) deaths and 571,590 (95% CI 253,490 to 917,820) disability-adjusted life-years (DALYs) in 2019. The number of smoking-related deaths and DALYs showed an upward trend, increasing by half from 1990 to 2019, while ASMR and ASDR declined in five sociodemographic indexes (SDI) regions, with the fastest decline in high SDI regions. For geographical regions, Western Europe and East Asia were the high-risk areas of prostate cancer deaths and DALYs attributable to smoking, among which China and the United States were the countries with the heaviest burden. The ASMR has decreased in all age groups, with the fastest decrease occurring in 75-79 years old. The ASMR or ASDR tended to increase in countries with the lowest SDI, but declined in countries with the highest SDI. The EAPC in ASMR or ASDR was highly negatively correlated with Human Development Index (HDI) in 2019, with coefficients 0.46.

CONCLUSION

The number of smoking-related prostate cancer deaths and DALYs continued to increase globally, whereas its ASMR and ASDR have been decreasing. This substantial progress is particularly significant in developed regions and vary across geographic regions. Medical strategies to prevent and reduce the burden should be adjusted and implemented based on country-specific disease prevalence.

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.

An analysis of time trends in breast and prostate cancer mortality rates in Lithuania, 1986-2020

Background

Breast cancer (BC) and prostate cancer (PC) mortality rates in Lithuania remain comparatively high despite the ongoing BC and PC screening programmes established in 2006. The aim of this study was to investigate time trends in BC and PC mortality rates in Lithuania evaluating the effects of age, calendar period of death, and birth-cohort over a 35-year time span.

Methods

We obtained death certification data for BC in women and PC in men for Lithuania during the period 1986–2020 from the World Health Organisation database. Age-standardised mortality rates were analysed using Joinpoint regression. Age-period-cohort models were used to assess the independent age, period and cohort effects on the observed mortality trends.

Results

Joinpoint regression analysis indicated that BC mortality increased by 1.6% annually until 1996, and decreased by − 1.2% annually thereafter. The age-period-cohort analysis suggests that temporal trends in BC mortality rates could be attributed mainly to cohort effects. The cohort effect curvature showed the risk of BC death increased in women born prior to 1921, remained stable in cohorts born around 1921–1951 then decreased; however, trend reversed in more recent generations. The period effect curvature displayed a continuous decrease in BC mortality since 1991–1995. For PC mortality, after a sharp increase by 3.0%, rates declined from 2007 by − 1.7% annually. The period effect was predominant in PC mortality, the curvature displaying a sharp increase until 2001–2005, then decrease.

Conclusions

Modestly declining recent trends in BC and PC mortality are consistent with the introduction of widespread mammography and PSA testing, respectively, lagging up to 10 years. The study did not show that screening programme introduction played a key role in BC mortality trends in Lithuania. Screening may have contributed to favourable recent changes in PC mortality rates in Lithuania, however the effect was moderate and limited to age groups < 65 years. Further improvements in early detection methods followed by timely appropriate treatment are essential for decreasing mortality from BC and PC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14207-4.

The Effect of Advances in Lung-Cancer Treatment on Population Mortality

BACKGROUND

Lung cancer is made up of distinct subtypes, including non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). Although overall mortality from lung cancer has been declining in the United States, little is known about mortality trends according to cancer subtype at the population level because death certificates do not record subtype information.

METHODS

Using data from Surveillance, Epidemiology, and End Results (SEER) areas, we assessed lung-cancer mortality and linked deaths from lung cancer to incident cases in SEER cancer registries. This allowed us to evaluate population-level mortality trends attributed to specific subtypes (incidence-based mortality). We also evaluated lung-cancer incidence and survival according to cancer subtype, sex, and calendar year. Joinpoint software was used to assess changes in incidence and trends in incidence-based mortality.

RESULTS

Mortality from NSCLC decreased even faster than the incidence of this subtype, and this decrease was associated with a substantial improvement in survival over time that corresponded to the timing of approval of targeted therapy. Among men, incidence-based mortality from NSCLC decreased 6.3% annually from 2013 through 2016, whereas the incidence decreased 3.1% annually from 2008 through 2016. Corresponding lung cancer-specific survival improved from 26% among men with NSCLC that was diagnosed in 2001 to 35% among those in whom it was diagnosed in 2014. This improvement in survival was found across all races and ethnic groups. Similar patterns were found among women with NSCLC. In contrast, mortality from SCLC declined almost entirely as a result of declining incidence, with no improvement in survival. This result correlates with limited treatment advances for SCLC in the time frame we examined.

CONCLUSIONS

Population-level mortality from NSCLC in the United States fell sharply from 2013 to 2016, and survival after diagnosis improved substantially. Our analysis suggests that a reduction in incidence along with treatment advances - particularly approvals for and use of targeted therapies - is likely to explain the reduction in mortality observed during this period.

Cancer Incidence in Older Adults in the United States: Characteristics, Specificity, and Completeness of the Data

INTRODUCTION

The number of cancer cases in the United States continues to grow as the number of older adults increases. Accurate, reliable and detailed incidence data are needed to respond effectively to the growing human costs of cancer in an aging population. The purpose of this study was to examine the characteristics of incident cases and evaluate the impact of death-certificate-only (DCO) cases on cancer incidence rates in older adults.

METHODS

Using data from 47 cancer registries and detailed population estimates from the Surveillance, Epidemiology and End Results (SEER) Program, we examined reporting sources, methods of diagnosis, tumor characteristics, and calculated age-specific incidence rates with and without DCO cases in adults aged 65 through ≥95 years, diagnosed 2011 through 2015, by sex and race/ethnicity.

RESULTS

The percentage of cases (all cancers combined) reported from a hospital decreased from 90.6% (ages 65-69 years) to 69.1% (ages ≥95 years) while the percentage of DCO cases increased from 1.1% to 19.6%. Excluding DCO cases, positive diagnostic confirmation decreased as age increased from 96.8% (ages 65-69 years) to 69.2% (ages ≥95 years). Compared to incidence rates that included DCO cases, rates in adults aged ≥95 years that excluded DCO cases were 41.5% lower in Black men with prostate cancer and 29.2% lower in Hispanic women with lung cancer.

DISCUSSION

Loss of reported tumor specificity with age is consistent with fewer hospital reports. However, the majority of cancers diagnosed in older patients, including those aged ≥95 years, were positively confirmed and were reported with known site, histology, and stage information. The high percentage of DCO cases among patients aged ≥85 years suggests the need to explore additional sources of follow-back to help possibly identify an earlier incidence report. Interstate data exchange following National Death Index linkages may help registries identify and remove erroneous DCO cases from their databases.

Recent Global Patterns in Prostate Cancer Incidence and Mortality Rates

CONTEXT

Previous studies have reported significant variation in prostate cancer rates and trends mainly due to differences in detection practices, availability of treatment, and underlying genetic susceptibility.

OBJECTIVE

To assess recent worldwide prostate cancer incidence, mortality rates, and trends using up-to-date incidence and mortality data.

EVIDENCE ACQUISITION

We present estimated age-standardized prostate cancer incidence and mortality rates by country and world regions for 2018 based on the GLOBOCAN database. We also examined rates and temporal trends for incidence (44 countries) and mortality (76 countries) based on data series from population-based registries.

EVIDENCE SYNTHESIS

The highest estimated incidence rates were found in Australia/New Zealand, Northern America, Western and Northern Europe, and the Caribbean, and the lowest rates were found in South-Central Asia, Northern Africa, and South-Eastern and Eastern Asia. The highest estimated mortality rates were found in the Caribbean (Barbados, Trinidad and Tobago, and Cuba), sub-Saharan Africa (South Africa), parts of former Soviet Union (Lithuania, Estonia, and Latvia), whereas the lowest rates were found in Asia (Thailand and Turkmenistan). Prostate cancer incidence rates during the most recent 5 yr declined (five countries) or stabilized (35 countries), after increasing for many years; in contrast, rates continued to increase for four countries in Eastern Europe and Asia. During the most recent 5 data years, mortality rates among the 76 countries examined increased (three countries), remained stable (59 countries), or decreased (14 countries).

CONCLUSIONS

As evident from available data, prostate cancer incidence and mortality rates have been on the decline or have stabilized recently in many countries, with decreases more pronounced in high-income countries. These trends may reflect a decline in prostate-specific antigen testing (incidence) and improvements in treatment (mortality).

PATIENT SUMMARY

We examined recent trends in prostate cancer incidence and mortality rates in 44 and 76 countries, respectively, and found that rates in most countries stabilized or decreased.

Cancer statistics for adults aged 85 years and older, 2019

Adults aged 85 years and older, the "oldest old," are the fastest-growing age group in the United States, yet relatively little is known about their cancer burden. Combining data from the National Cancer Institute, the North American Association of Central Cancer Registries, and the National Center for Health Statistics, the authors provide comprehensive information on cancer occurrence in adults aged 85 years and older. In 2019, there will be approximately 140,690 cancer cases diagnosed and 103,250 cancer deaths among the oldest old in the United States. The most common cancers in these individuals (lung, breast, prostate, and colorectum) are the same as those in the general population. Overall cancer incidence rates peaked in the oldest men and women around 1990 and have subsequently declined, with the pace accelerating during the past decade. These trends largely reflect declines in cancers of the prostate and colorectum and, more recently, cancers of the lung among men and the breast among women. We note differences in trends for some cancers in the oldest age group (eg, lung cancer and melanoma) compared with adults aged 65 to 84 years, which reflect elevated risks in the oldest generations. In addition, cancers in the oldest old are often more advanced at diagnosis. For example, breast and colorectal cancers diagnosed in patients aged 85 years and older are about 10% less likely to be diagnosed at a local stage compared with those diagnosed in patients aged 65 to 84 years. Patients with cancer who are aged 85 years and older have the lowest relative survival of any age group, with the largest disparities noted when cancer is diagnosed at advanced stages. They are also less likely to receive surgical treatment for their cancers; only 65% of breast cancer patients aged 85 years and older received surgery compared with 89% of those aged 65 to 84 years. This difference may reflect the complexities of treating older patients, including the presence of multiple comorbidities, functional declines, and cognitive impairment, as well as competing mortality risks and undertreatment. More research on cancer in the oldest Americans is needed to improve outcomes and anticipate the complex health care needs of this rapidly growing population.

Prostate cancer incidence and mortality in the Baltic states, Belarus, the Russian Federation and Ukraine

BACKGROUND

Prostate cancer incidence varies internationally largely attributable to differences in prostate-specific antigen (PSA) use. The aim of this study was to provide the most recent detailed international epidemiological comparison of prostate cancer incidence and mortality in six north-eastern European countries (Belarus, Estonia, Latvia, Lithuania, the Russian Federation and Ukraine).

METHODS

The number of incident prostate cancer cases was obtained from the countries national cancer registries. Prostate cancer mortality and corresponding population data were extracted from the WHO Mortality Database. Age-specific and age-standardised incidence and mortality rates were calculated (European Standard). The joinpoint regression model was used to provide an average annual percentage change and to detect points in time where significant changes in trends occurred. The observation period was between 13 (Ukraine) and 48 (Estonia) years regarding incidence and around 30 years regarding mortality.

RESULTS

The comparison of prostate cancer incidence in six European countries showed almost sixfold differences in the age-adjusted rates in most recent years with highest incidence rates in Lithuania and Estonia. Through the observation period, overall a continuous rise was seen in incidence in all countries and a continuous rise in mortality, with a stabilisation in Estonia and a decrease in Lithuania in recent years. Data limitations included a descriptive design using ecological data.

CONCLUSIONS

A widespread use of PSA testing seems to be responsible for the changes in the epidemiology of the disease in north-eastern European countries. Substantial variation in the incidence of prostate cancer in the Baltic states suggests the possibility that PSA performance and utilisation spread have had a major influence on observed incidence trends, with a lack of effect on prostate cancer mortality.

Association of Cataract Surgery With Mortality in Older Women: Findings from the Women's Health Initiative

Importance

Previous studies have suggested an association between cataract surgery and decreased risk for all-cause mortality potentially through a mechanism of improved health status and functional independence, but the association between cataract surgery and cause-specific mortality has not been previously studied and is not well understood.

Objective

To examine the association between cataract surgery and total and cause-specific mortality in older women with cataract.

Design, Setting, and Participants

This prospective cohort study included nationwide data collected from the Women's Health Initiative (WHI) clinical trial and observational study linked with the Medicare claims database. Participants in the present study were 65 years or older with a diagnosis of cataract in the linked Medicare claims database. The WHI data were collected from January 1, 1993, through December 31, 2015. Data were analyzed for the present study from July 1, 2014, through September 1, 2017.

Exposures

Cataract surgery as determined by Medicare claims codes.

Main Outcomes and Measures

The outcomes of interest included all-cause mortality and mortality attributed to vascular, cancer, accidental, neurologic, pulmonary, and infectious causes. Mortality rates were compared by cataract surgery status using the log-rank test and Cox proportional hazards regression models adjusting for demographics, systemic and ocular comorbidities, smoking, alcohol use, body mass index, and physical activity.

Results

A total of 74 044 women with cataract in the WHI included 41 735 who underwent cataract surgery. Mean (SD) age was 70.5 (4.6) years; the most common ethnicity was white (64 430 [87.0%]), followed by black (5293 [7.1%]) and Hispanic (1723 [2.3%]). The mortality rate was 2.56 per 100 person-years in both groups. In covariate-adjusted Cox models, cataract surgery was associated with lower all-cause mortality (adjusted hazards ratio [AHR], 0.40; 95% CI, 0.39-0.42) as well as lower mortality specific to vascular (AHR, 0.42; 95% CI, 0.39-0.46), cancer (AHR, 0.31; 95% CI, 0.29-0.34), accidental (AHR, 0.44; 95% CI, 0.33-0.58), neurologic (AHR, 0.43; 95% CI, 0.36-0.53), pulmonary (AHR, 0.63; 95% CI, 0.52-0.78), and infectious (AHR, 0.44; 95% CI, 0.36-0.54) diseases.

Conclusions and Relevance

In older women with cataract in the WHI, cataract surgery is associated with lower risk for total and cause-specific mortality, although whether this association is explained by the intervention of cataract surgery is unclear. Further study of the interplay of cataract surgery, systemic disease, and disease-related mortality would be informative for improved patient care.

Association of Black Race With Prostate Cancer-Specific and Other-Cause Mortality

Importance

Black men are more likely to die of prostate cancer than white men. In men with similar stages of disease, the contribution of biological vs nonbiological differences to this observed disparity is unclear.

Objective

To quantify the association of black race with long-term survival outcomes after controlling for known prognostic variables and access to care among men with prostate cancer.

Design, Setting, and Participants

This multiple-cohort study included updated individual patient-level data of men with clinical T1-4N0-1M0 prostate cancer from the following 3 cohorts: Surveillance, Epidemiology, and End Results (SEER [n = 296 273]); 5 equal-access regional medical centers within the Veterans Affairs health system (VA [n = 3972]); and 4 pooled National Cancer Institute-sponsored Radiation Therapy Oncology Group phase 3 randomized clinical trials (RCTs [n = 5854]). Data were collected in the 3 cohorts from January 1, 1992, through December 31, 2013, and analyzed from April 27, 2017, through April 13, 2019.

Exposures

In the VA and RCT cohorts, all patients received surgery and radiotherapy, respectively, with curative intent. In SEER, radical treatment, hormone therapy, or conservative management were received.

Main Outcomes and Measures

Prostate cancer-specific mortality (PCSM). Secondary measures included other-cause mortality (OCM). To adjust for demographic-, cancer-, and treatment-related baseline differences, inverse probability weighting (IPW) was performed.

Results

Among the 306 100 participants included in the analysis (mean [SD] age, 64.9 [8.9] years), black men constituted 52 840 patients (17.8%) in the SEER cohort, 1513 (38.1%) in the VA cohort, and 1129 (19.3%) in the RCT cohort. Black race was associated with an increased age-adjusted PCSM hazard (subdistribution hazard ratio [sHR], 1.30; 95% CI, 1.23-1.37; P < .001) within the SEER cohort. After IPW adjustment, black race was associated with a 0.5% (95% CI, 0.2%-0.9%) increase in PCSM at 10 years after diagnosis (sHR, 1.09; 95% CI, 1.04-1.15; P < .001), with no significant difference for high-risk men (sHR, 1.04; 95% CI, 0.97-1.12; P = .29). No significant differences in PCSM were found in the VA IPW cohort (sHR, 0.85; 95% CI, 0.56-1.30; P = .46), and black men had a significantly lower hazard in the RCT IPW cohort (sHR, 0.81; 95% CI, 0.66-0.99; P = .04). Black men had a significantly increased hazard of OCM in the SEER (sHR, 1.30; 95% CI, 1.27-1.34; P < .001) and RCT (sHR, 1.17; 95% CI, 1.06-1.29; P = .002) IPW cohorts.

Conclusions and Relevance

In this study, after adjustment for nonbiological differences, notably access to care and standardized treatment, black race did not appear to be associated with inferior stage-for-stage PCSM. A large disparity remained in OCM for black men with nonmetastatic prostate cancer.

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.

Decreasing Disease-Specific Mortality of Differentiated Thyroid Cancer in Korea: A Multicenter Cohort Study

BACKGROUND

Recent studies have reported improved survival in patients with thyroid cancer. This study evaluated the changes in disease-specific survival (DSS) of patients with differentiated thyroid cancer (DTC) in association with clinicopathologic characteristics from 1996 to 2005 in Korea.

METHODS

This was a retrospective, multicenter cohort study. A total of 4398 DTC patients were included, and they were classified according to the year of initial surgery: 1996-2000 (period 1), 2001-2003 (period 2), and 2004-2005 (period 3).

RESULTS

During the study period, patient age and the proportion of papillary thyroid cancer increased gradually. Primary tumors became smaller (2.3 ± 1.4 cm at period 1 to 1.5 ± 1.2 cm at period 3; p < 0.001). The proportion of high-volume lymph node metastases decreased significantly (20% at period 1 to 13% at period 3; p for trend <0.001). DSS differed significantly according to period during the median 10 years follow-up (p = 0.002). The 10-year DSS rates were 98.0%, 98.7%, and 99.2% in periods 1, 2, and 3, respectively. After adjusting for various characteristics, the disease-specific mortality risk was significantly lower during period 2 (hazard ratio = 0.49 [confidence interval CI 0.25-0.90], p = 0.021) and period 3 (hazard ratio = 0.40 [confidence interval 0.21-0.77], p = 0.006) compared to that of period 1. This trend was also significant in a subgroup analysis of low (I-II) and high (III-IV) TNM stages.

CONCLUSIONS

The disease-specific mortality of patients with DTC in Korea decreased over time. Earlier detection of small DTCs with less extensive disease and standardization of treatment may be associated with this phenomenon.

Effectiveness of the Korean National Cancer Screening Program in Reducing Gastric Cancer Mortality

BACKGROUND & AIMS

It is not clear whether screening for gastric cancer by upper endoscopy or upper gastrointestinal (UGI) series examinations (looking at the upper and middle sections of the gastrointestinal tract by imaging techniques) reduces mortality. Nevertheless, the Korean National Cancer Screening Program for gastric cancer was launched in 1999 to screen individuals 40 years and older for gastric cancer using these techniques. We evaluated the effectiveness of these techniques in gastric cancer detection and compared their effects on mortality in the Korean population.

METHODS

We performed a nested case-control study using data from the Korean National Cancer Screening Program for gastric cancer since 2002. A total of 16,584,283 Korean men and women, aged 40 years and older, comprised the cancer-free cohort. Case subjects (n = 54,418) were defined as individuals newly diagnosed with gastric cancer from January 2004 through December 2009 and who died before December 2012. Cases were matched with controls (subjects who were alive on the date of death of the corresponding case subject, n = 217,672) for year of entry into the study cohort, age, sex, and socioeconomic status. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained via conditional logistic regression analysis.

RESULTS

Compared with subjects who had never been screened, the overall OR for dying from gastric cancer among ever-screened subjects was 0.79 (95% CI, 0.77-0.81). According to screening modality, the ORs of death from gastric cancer were 0.53 (95% CI, 0.51-0.56) for upper endoscopy and 0.98 (95% CI, 0.95-1.01) for UGI series. As the number of endoscopic screening tests performed per subject increased, the ORs of death from gastric cancer decreased: 0.60 (95% CI, 0.57-0.63), 0.32 (95% CI, 0.28-0.37), and 0.19 (95% CI, 0.14-0.26) for once, twice, and 3 or more times, respectively.

CONCLUSIONS

Within the Korean National Cancer Screening Program, patients who received an upper endoscopy were less likely to die from gastric cancer; no associations were found for UGI series.

Trends in the Incidence of Fatal Prostate Cancer in the United States by Race

BACKGROUND

Prostate-specific antigen (PSA) testing has dramatically changed the composition of prostate cancer (PCa), making it difficult to interpret incidence trends. New methods are needed to examine temporal trends in the incidence of clinically significant PCa and whether trends vary by race.

OBJECTIVE

To conduct an in-depth analysis of incidence trends in clinically significant PCa, defined as cases in which PCa was the underlying cause of death within 10 yr of diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

We extracted incident PCa cases during the period 1975-2002 and associated causes of death and survival through 2012 from nine cancer registries in the population-based Surveillance Epidemiology and End Results program database.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We applied joinpoint regression analysis to identify when significant changes in trends occurred and age-period-cohort models to examine longitudinal and cross-sectional trends in the incidence of fatal PCa.

RESULTS AND LIMITATIONS

Among 51 680 fatal PCa cases, incidence increased 1% per year prior to 1992, declined 15% per year from 1992 to 1995, and further declined by 5% per year through 2002. Age-specific incidence rates of fatal disease decreased >2% per year among men aged ≥60 yr, yet rates remained relatively stable among men aged ≤55 yr. Fatal disease rates were >2-fold higher in black men compared with white men, a racial disparity that increased to 4.2-fold among younger men.

CONCLUSIONS

The incidence of fatal PCa substantially declined after widespread PSA screening and treatment advances. Nevertheless, rates of fatal disease among younger men have remained relatively stable, suggesting the need for additional attention to early onset PCa, especially among black men. The persistent black-to-white racial disparity observed in fatal PCa underscores the need for greater understanding of the causes of this difference so that strategies can be implemented to eliminate racial disparities.

PATIENT SUMMARY

We assessed how the incidence of ultimately fatal prostate cancer (PCa) changed over time. We found that the incidence of fatal PCa declined by >50% since the introduction of prostate-specific antigen testing and advances in treatment options; however, incidence rates among younger men remained relatively stable, and younger black men exhibited a 4.2-fold higher risk for fatal disease compared with white men.

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.

Disparities in long-term radiographic follow-up after cystectomy for bladder cancer: Analysis of the SEER-Medicare database

Introduction:

It is uncertain whether there are disparities related to receiving long-term radiographic follow-up after cystectomy performed for bladder cancer, and whether intensive follow-up influences survival.

Materials and Methods:

We analyzed 2080 patients treated with cystectomy between 1992 and 2004 isolated from the SEER-Medicare database. The number of abdominal computerized tomography scans performed in patients surviving 2 years after surgery was used as an indicator of long-term radiographic follow-up to exclude patients with early failures.

Results:

Patients were mainly males (83.18%), had a mean age at diagnosis of 73.4 ± 6.6 (standard deviation) years, and mean survival of 4.6 ± 3.2 years. Multivariate analysis showed age >70 (odds ratio [OR]: 0.796, 95% confidence interval [CI]: 0.651–0.974), African American race (OR: 0.180, 95% CI: 0.081–0.279), and Charlson comorbidity score >2 (OR: 0.694, 95% CI: 0.505–0.954) to be associated with lower odds of long-term radiographic follow-up. Higher disease stage (Stage T4N1) (OR: 1.873, 95% CI: 1.491–2.353), higher quartile for education (OR: 5.203, 95% CI: 1.072–9.350) and higher quartile for income (OR: 6.940, 95% CI: 1.444–12.436) were associated with increased odds of long-term radiographic follow-up. Interestingly, more follow-up with imaging after cystectomy did not improve cancer-specific or overall survival in these patients.

Conclusion:

There are significant age, race, and socioeconomic disparities in long-term radiographic follow-up after radical cystectomy. However, more radiographic follow-up may not be associated with better survival.

Has prostate cancer mortality stopped its decline in Spain?

OBJECTIVE

To describe the evolution of prostate cancer mortality in Spain during the period 1980-2013.

SUBJECT AND METHOD

The prostate cancer mortality data and population data needed to calculate the indicators were provided by the National Institute of Statistics. We calculated the specific rates by age group, raw and standardised globally using the direct method (European standard population). The rates are expressed for 100,000 person-years. For the analysis of trends in the rates, we used joinpoint regression models.

RESULTS

The overall rates adjusted for age in Spain decreased from 21.7 to 15.4 deaths per 100,000 men-years between the starting and ending date of the study period (annual percentage change: -.9%; P<.05). The joinpoint analysis reflects 2 periods: 1980-1998 (.7% annual increase; P<.05) and 1998-2013, during which the rates decreased significantly (-3%; P<.05). Except for the autonomous cities of Ceuta and Melilla where the rates remained stable over the course of the study period, the communities showed 1 or 2 points of inflection in the trends, and all had a final period with a reduction in the rates (except for Galicia and Catalonia, where the rates stabilised in 2008-2013).

CONCLUSION

The decline in prostate cancer mortality in Spain appears to have stopped in Galicia and Catalonia.

Contributions of Subtypes of Non-Hodgkin Lymphoma to Mortality Trends

BACKGROUND

Non-Hodgkin lymphoma (NHL) comprises distinct tumor subtypes. Although mortality from NHL overall has changed dramatically in the United States over time, little is known about trends for subtypes, because death certificates do not record this information.

METHODS

Using data from U.S. Surveillance, Epidemiology, and End Results (SEER) areas, we assessed NHL mortality rates and mapped NHL deaths to incident NHL cases in SEER cancer registries. This allowed us to evaluate population-level mortality trends attributed to specific NHL subtypes (incidence-based mortality; IBM). We also describe NHL incidence and survival after NHL diagnosis by calendar year. We used Joinpoint to identify years when IBM and incidence rate trends changed slope.

RESULTS

Overall NHL mortality rates increased during 1975-1997, peaking at 10.9 per 100,000 person-years, then decreased subsequently in 1997-2011. Overall IBM rates mirror this trend during 1990-2011. For B-cell NHL subtypes, IBM rates decreased beginning in the mid-1990s, with yearly declines of -3.0% for diffuse large B-cell lymphoma (DLBCL), -2.7% for chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), and -5.3% for follicular lymphoma. Incidence rates for these subtypes did not decrease until after 2003. Corresponding 5-year cancer-specific survival increased dramatically over time for DLBCL (from 37%-66%), CLL/SLL (69%-84%), and follicular lymphoma (69%-82%). IBM for peripheral T-cell lymphoma was flat during 2006-2011, although incidence increased.

CONCLUSIONS

Mortality due to three common B-cell NHL subtypes has fallen over time in the United States.

IMPACT

This decline reflects better survival after NHL diagnosis, likely from improved therapies, because the decline in NHL incidence occurred later.

Semiparametric estimation in the proportional hazard model accounting for a misclassified cause of failure

Misclassified causes of failures are a common phenomenon in competing risks survival data such as cancer mortality. We propose new estimating equations for a semiparametric proportional hazards (PH) model with misattributed causes of failures. Unlike other methods, the estimator does not require any parametric assumptions on baseline cause-specific hazard rates. It is shown that the estimators for regression coefficients are consistent and asymptotically normal. Simulation results support the theoretical analysis in finite samples. The methods are applied to analyze prostate cancer survival.

Racial-Sex Disparities--A Challenging Battle Against Cancer Mortality in the USA

Decline in US cancer mortality has recently been reported, based on either pooled mortality of all cancer sites or age-adjusted mortality rates of specific sites. While the former could be dominated by a few cancer sites and would not reflect that of other sites, the latter used the US 2000 Population as reference for age-standardization, which was lack of justification. This study aimed to examine US cancer mortality trend and disparities in sites, races, and sex. We studied cancer incidence-based mortality by race and sex from 1974 to 2008 of cervix, prostate, colon and rectum, lung, leukemia, liver, pancreas, and stomach in the Surveillance, Epidemiology, and End Results database. We developed a model-based mortality rate and examined rate ratio of each calendar period to the first period within each race-sex group. Cancer mortality of cervix, colon and rectum, leukemia, and stomach declined in all groups. Prostate cancer increased first in all racial groups and decreased thereafter at different pace. Lung cancer declined among males of all races but increased among females. Liver cancer increased steadily fast among white and black females, doubled in whites and black males, and climbed slowly in other races. Pancreas cancer declined among black males and females, and changed little among others. Cancer mortality trend presents heterogeneity across sites, races, and sex. Recently observed mortality decline may not reflect every cancer site or group. More effort needs to focus on specific race-sex groups that had increasing lung and liver cancer mortality.

Developing a follow-up strategy for patients with PSA ranging from 4 to 10 ng/ml via a new model to reduce unnecessary prostate biopsies

Objective

The aim of this study was to develop a follow-up strategy based on the new model to reduce unnecessary prostate biopsies in patients with prostate specific antigen (PSA) ranging from 4 to 10 ng/ml.

Methods

A total of 436 patients with PSA ranging from 4 to 10 ng/ml who had undergone transrectal ultrasound (TRUS)-guided prostate biopsy were evaluated during the first stage. Age, PSA, free PSA (fPSA), digital rectal examination (DRE) findings, ultrasonic hypoechoic mass, ultrasonic microcalcifications, prostate volume (PV) and PSA density (PSAD) were considered as predictive factors. A multiple logistic regression analysis involving a backward elimination selection procedure was applied to select independent predictors. After a comprehensive analysis of all results, we developed a new model to assess the risk of prostate cancer and an effective follow-up strategy.

Results

Age, PSA, PV, fPSA, rate of abnormal DRE findings and rate of hypoechoic masses detected by TRUS were included in our model. A significantly greater area under the receiver-operating characteristic curve was obtained in our model when compared with using PSA alone (0.782 vs. 0.566). Patients were grouped according to the value of prostate cancer risk (PCaR). In the second stage of our study, patients with PCaR>0.52 were recommended to undergo biopsies immediately while the rest of the patients continued close follow-up observation. Compared with the first stage, the detection rate of PCa in the second stage was significantly increased (33.0% vs 21.1%, p = 0.012). There was no significant difference between the two stages in distribution of the Gleason score (p = 0.808).

Conclusions

We developed a follow-up strategy based on the new model, which reduced unnecessary prostate biopsies without delaying patients’ diagnoses and treatments.

Clustering of trend data using joinpoint regression models

In this paper, we propose methods to cluster groups of two-dimensional data whose mean functions are piecewise linear into several clusters with common characteristics such as the same slopes. To fit segmented line regression models with common features for each possible cluster, we use a restricted least squares method. In implementing the restricted least squares method, we estimate the maximum number of segments in each cluster by using both the permutation test method and the Bayes information criterion method and then propose to use the Bayes information criterion to determine the number of clusters. For a more effective implementation of the clustering algorithm, we propose a measure of the minimum distance worth detecting and illustrate its use in two examples. We summarize simulation results to study properties of the proposed methods and also prove the consistency of the cluster grouping estimated with a given number of clusters. The presentation and examples in this paper focus on the segmented line regression model with the ordered values of the independent variable, which has been the model of interest in cancer trend analysis, but the proposed method can be applied to a general model with design points either ordered or unordered.

A composite metric for assessing data on mortality and causes of death: the vital statistics performance index

BACKGROUND

Timely and reliable data on causes of death are fundamental for informed decision-making in the health sector as well as public health research. An in-depth understanding of the quality of data from vital statistics (VS) is therefore indispensable for health policymakers and researchers. We propose a summary index to objectively measure the performance of VS systems in generating reliable mortality data and apply it to the comprehensive cause of death database assembled for the Global Burden of Disease (GBD) 2013 Study.

METHODS

We created a Vital Statistics Performance Index, a composite of six dimensions of VS strength, each assessed by a separate empirical indicator. The six dimensions include: quality of cause of death reporting, quality of age and sex reporting, internal consistency, completeness of death reporting, level of cause-specific detail, and data availability/timeliness. A simulation procedure was developed to combine indicators into a single index. This index was computed for all country-years of VS in the GBD 2013 cause of death database, yielding annual estimates of overall VS system performance for 148 countries or territories.

RESULTS

The six dimensions impacted the accuracy of data to varying extents. VS performance declines more steeply with declining simulated completeness than for any other indicator. The amount of detail in the cause list reported has a concave relationship with overall data accuracy, but is an important driver of observed VS performance. Indicators of cause of death data quality and age/sex reporting have more linear relationships with simulated VS performance, but poor cause of death reporting influences observed VS performance more strongly. VS performance is steadily improving at an average rate of 2.10% per year among the 148 countries that have available data, but only 19.0% of global deaths post-2000 occurred in countries with well-performing VS systems.

CONCLUSIONS

Objective and comparable information about the performance of VS systems and the utility of the data that they report will help to focus efforts to strengthen VS systems. Countries and the global health community alike need better intelligence about the accuracy of VS that are widely and often uncritically used in population health research and monitoring.

The effect of extent of surgery and number of lymph node metastases on overall survival in patients with medullary thyroid cancer

CONTEXT

Total thyroidectomy with central lymph node dissection is recommended in patients with medullary thyroid cancer (MTC). However, the relationship between disease severity and extent of resection on overall survival remains unknown.

OBJECTIVE

The aim of the study was to identify the effect of surgery on overall survival in MTC patients.

METHODS

Using data from 2968 patients with MTC diagnosed between 1998 and 2005 from the National Cancer Database, we determined the relationship between the number of cervical lymph node metastases, tumor size, distant metastases, and extent of surgery on overall survival in patients with MTC.

RESULTS

Older patient age (5.69 [95% CI, 3.34-9.72]), larger tumor size (2.89 [95% CI, 2.14-3.90]), presence of distant metastases (5.68 [95% CI, 4.61-6.99]), and number of positive regional lymph nodes (for ≥16 lymph nodes, 3.40 [95% CI, 2.41-4.79]) were independently associated with decreased survival. Overall survival rate for patients with cervical lymph nodes resected and negative, cervical lymph nodes not resected, and 1-5, 6-10, 11-16, and ≥16 cervical lymph node metastases was 90, 76, 74, 61, 69, and 55%, respectively. There was no difference in survival based on surgical intervention in patients with tumor size ≤ 2 cm without distant metastases. In patients with tumor size > 2.0 cm and no distant metastases, all surgical treatments resulted in a significant improvement in survival compared to no surgery (P < .001). In patients with distant metastases, only total thyroidectomy with regional lymph node resection resulted in a significant improvement in survival (P < .001).

CONCLUSIONS

The number of lymph node metastases should be incorporated into MTC staging. The extent of surgery in patients with MTC should be tailored to tumor size and distant metastases.

Methods and rationale used in a matched cohort study of the incidence of new primary cancers following prostate cancer

Objectives

We describe several methodological issues that were addressed in conducting a Danish population-based matched cohort study comparing rates of new primary cancers (NPCs) in men with and without prostate cancer (PC).

Methods

We matched 30,220 men with PC to 151,100 men without PC (comparators) on age (±2 years) and PC diagnosis/index date. We focused on several methodological issues: 1) to address survival differences between the cohorts we compared rates with and without censoring comparators on the date their matched PC patient died or was censored; 2) to address diagnostic bias, we excluded men with a history of cancer from the comparator cohort; 3) to address prostate cancer immunity, we graphed the hazard of NPC in both cohorts, with and without prostate cancer as an outcome; 4) we used empirical Bayes methods to explore the effect of adjusting for multiple comparisons.

Results

After 18 months of follow-up, cumulative person-time was lower in the PC than comparator cohort due to higher mortality among PC patients. Terminating person-time in comparators at the matched PC patient’s death or loss to follow-up resulted in comparable person-time up to 30 months of follow-up and lower person-time among comparators thereafter. The hazard of NPC was lower among men with PC than comparators throughout follow-up. There was little difference in rates beyond the first four years of follow-up after removing PC as an outcome. Empirical Bayes adjustment for multiple comparisons had little effect on the estimates.

Conclusion

Addressing the issues of competing risks, treatment interference or diagnostic bias, prostate cancer immunity due to radical prostatectomy, and multiple comparisons lowered the deficit rate of NPCs among men with a history of PC compared with those without PC. However, the differing rates of NPCs may also be due to risk factor differences between the cohorts.

Predicting county-level cancer incidence rates and counts in the USA

Many countries, including the USA, publish predicted numbers of cancer incidence and death in current and future years for the whole country. These predictions provide important information on the cancer burden for cancer control planners, policymakers and the general public. Based on evidence from several empirical studies, the joinpoint (segmented-line linear regression) model (JPM) has been adopted by the American Cancer Society to estimate the number of new cancer cases in the USA and in individual states since 2007. Recently, cancer incidence in smaller geographic regions such as counties, and local policy makers are increasingly interested with Federal Information Processing Standard code regions. The natural extension is to directly apply the JPM to county-level cancer incidence data. The direct application has several drawbacks and its performance has not been evaluated. To address the concerns, we developed a spatial random-effects JPM for county-level cancer incidence data. The proposed model was used to predict both cancer incidence rates and counts at the county level. The standard JPM and the proposed method were compared through a validation study. The proposed method outperformed the standard JPM for almost all cancer sites, especially for moderate or rare cancer sites and for counties with small population sizes. As an application, we predicted county-level prostate cancer incidence rates and counts for the year 2011 in Connecticut.

PSA screening and deaths from prostate cancer after diagnosis--a population based analysis

BACKGROUND

The United States Preventative Health Task Force recently recommended prostate specific antigen (PSA) screening be abandoned, believing the results of prior studies failed to show benefits that outweighed risks. Prior analyses did not include a complete 10 year follow-up in their analyses.

METHODS

SEER rate sessions were used to obtain for U.S. White and Black men age-adjusted incidence rates for prostate cancer, in total and by loco-regional and distant (D2) spread for 1983-2009, as well as for prostate cancer diagnoses with associated prostate cancer deaths within 10 years of diagnosis (incidence based mortality rates) for 1983-1999. The SEER-Stat Program was used to tabulate rate estimates and calculate standard errors. The Joinpoint Regression Program was used to provide estimates and 95% confidence intervals (CI) of annual percent changes (APC) and times at which APC changed (joinpoints), as well as to test for parallelism to see if APC's differed between groups of rates.

RESULTS

All analyses showed a 1991-1993 joinpoint, consistent with an impact of PSA screening. Between 1991 and 1999, incidence based mortality rates showed a decline for Whites of 10.9% (CI 9.2%-12.7%) and for Blacks of 11.6% (CI 9.7%-13.4%); incidence based mortality and D2 spread rate curves were similar (P > 0.05, test for parallelism).

CONCLUSION

Incidence based mortality declined by about 10% per year between 1991 and 1999 in a fashion similar to that of D2 spread, but not loco-regional spread or overall, incidence.

Model-based patterns in prostate cancer mortality worldwide

Background:

Prostate cancer mortality has been decreasing in several high income countries and previous studies analysed the trends mostly according to geographical criteria. We aimed to identify patterns in the time trends of prostate cancer mortality across countries using a model-based approach.

Methods:

Model-based clustering was used to identify patterns of variation in prostate cancer mortality (1980–2010) across 37 European, five non-European high-income countries and four leading emerging economies. We characterised the patterns observed regarding the geographical distribution and gross national income of the countries, as well as the trends observed in mortality/incidence ratios.

Results:

We identified three clusters of countries with similar variation in prostate cancer mortality: pattern 1 (‘no mortality decline'), characterised by a continued increase throughout the whole period; patterns 2 (‘later mortality decline') and 3 (‘earlier mortality decline') depict mortality declines, starting in the late and early 1990s, respectively. These clusters are also homogeneous regarding the variation in the prostate cancer mortality/incidence ratios, while are heterogeneous with reference to the geographical region of the countries and distribution of the gross national income.

Conclusion:

We provide a general model for the description and interpretation of the trends in prostate cancer mortality worldwide, based on three main patterns.