Counting the Cost of Diabetes in the Solomon Islands and Nauru

Aim

To determine the costs associated with diabetes to governments, people with diabetes and their carers, and its impact on quality of life in two Pacific Island countries—the Solomon Islands and Nauru.

Materials and Methods

This cross-sectional cost of illness study was conducted on 330 people with type 2 diabetes (197 from the Solomon Islands and 133 from Nauru) using a structured cost of illness survey questionnaire adapted from the Australian DiabCo$t study. Quality of life was measured by the EQ-5D Visual Analogue Scale.

Results

There were 330 respondents (50% female; mean duration of diabetes 10.9 years; mean age 52.6 years). The estimated annual national cost of diabetes incurred by the Solomon Islands government was AUD12.8 million (AUD281 per person/year) and by Nauru government was AUD1.2 million (AUD747 per person/year). The major contribution to the government costs was inpatient services cost (71% in the Solomon Islands and 83% in Nauru). Annual expenditure for diabetes was approximately 20% of the governments’ annual health care expenditure. Considerable absenteeism and retirement from work due to diabetes was found.

Conclusions

This study found substantial public and personal costs associated with diabetes. The findings provide objective data on which health policy, funding and planning decisions about the prevention and control of diabetes in the Solomon Islands and Nauru can be reliably based and subsequently evaluated.     

Cancer epidemiology in the small nations of Pacific Islands

BackgroundPacific island countries and territories (PICTs) comprise 20,000–30,000 islands in the Pacific Ocean. PICTs face challenges in relation to small population sizes, geographic dispersion, increasing adoption of unhealthy life-styles and the burden of both communicable and non-communicable diseases, including cancer. This study reviews data on cancer incidence and mortality in the PICTs, with special focus on indigenous populations.MethodsPICTs with populations of <1.5 million (‘small nations’) were included in this study. Information on cancer incidence and mortality was extracted from the GLOBOCAN 2012 database. Scientific and grey literature was narratively reviewed for publications published after 2000.ResultsOf the 21 PICTs, seven countries were included in the GLOBOCAN 2012 (Fiji, French Polynesia, Guam, New Caledonia, Samoa, Solomon Islands, Vanuatu). The highest cancer incidence and mortality rates were reported in New Caledonia (age-standardized incidence and mortality rates 297.9 and 127.3 per 100.000) and French Polynesia (age-standardized incidence and mortality rates 255.0 and 134.4 per 100.000), with relatively low rates in other countries. Literature indicated that cancer was among the leading causes of deaths in most PICTs; thus they now experience a double burden of cancers linked to infections and life-style and reproductive factors. Further, ethnic differences in cancer incidence and mortality have been reported in some PICTs, including Fiji, Guam, New Caledonia and Northern Mariana Islands.ConclusionCancer incidence in the PICTs was recorded to be relatively low, with New Caledonia and French Polynesia being exceptions. Low recorded incidence is likely to be explained by incomplete cancer registration as cancer had an important contribution to mortality. Further endeavors are needed to develop and strengthen cancer registration infrastructure and practices and to improve data quality and registration coverage in the PICTs.     

Accuracy and completeness of the New Zealand Cancer Registry for staging of invasive breast cancer

PurposePopulation based cancer registries are an invaluable resource for monitoring incidence and mortality for many types of cancer. Research and healthcare decisions based on cancer registry data rely on the case completeness and accuracy of recorded data. This study was aimed at assessing completeness and accuracy of breast cancer staging data in the New Zealand Cancer Registry (NZCR) against a regional breast cancer register.MethodologyData from 2562 women diagnosed with invasive primary breast cancer between 1999 and 2011 included in the Waikato Breast Cancer Register (WBCR) were used to audit data held on the same individuals by the NZCR. WBCR data were treated as the benchmark.ResultsOf 2562 cancers, 315(12.3%) were unstaged in the NZCR. For cancers with a known stage in the NZCR, staging accuracy was 94.4%. Lower staging accuracies of 74% and 84% were noted for metastatic and locally invasive (involving skin or chest wall) cancers, respectively, compared with localized (97%) and lymph node positive (94%) cancers. Older age (>80 years), not undergoing therapeutic surgery and higher comorbidity score were significantly (p < 0.01) associated with unstaged cancer. The high proportion of unstaged cancer in the NZCR was noted to have led to an underestimation of the true incidence of metastatic breast cancer by 21%. Underestimation of metastatic cancer was greater for Māori (29.5%) than for NZ European (20.6%) women. Overall 5-year survival rate for unstaged cancer (NZCR) was 55.9%, which was worse than the 5-year survival rate for regional (77.3%), but better than metastatic (12.9%) disease.ConclusionsUnstaged cancer and accuracy of cancer staging in the NZCR are major sources of bias for the NZCR based research. Improving completeness and accuracy of staging data and increasing the rate of TNM cancer stage recording are identified as priorities for strengthening the usefulness of the NZCR.     

Transition of cancer in populations in India

Background & objectivesAn assessment of transition of cancer in India during the past 30 years, according to changes in demographic and epidemiologic risk factors was undertaken.Materials & methodsCancer registry data (http://www.ncdirindia.org), (population coverage <10%), was compared with transition in life-expectancy and prevalence on smoking, alcohol and obesity. We fitted linear regression to the natural logarithm of the estimated incidence rates of various cancer registries in India.ResultsBurden of cancer in India increased from 0.6 million in 1991 to 1.4 million in 2015. Among males, common cancers are lung (12.0%), mouth (11.4%), prostate (7.0%), and tongue (7.0%) and among females, they are breast (21.0%), cervix-uteri (12.1%), ovary (6.9%), and lung (4.9%) in 2012. Increased life-expectancy and population growth as well as increased use of alcohol and increased prevalence of overweight/obesity reflected an increase in all cancers in both genders except a reduction in infection-related cancers such as cervix-uteri and tobacco-related cancers such as pharynx (excludes nasopharynx) and oesophagus.Interpretation & conclusionTransition in demographics and epidemiologic risk factors, reflected an increase in all cancers in both genders except a reduction in a few cancers. The increasing incidence of cancer and its associated factors demands a planned approach to reduce its burden. The burden assessment needs to be strengthened by increasing the population coverage of cancer registries. Continued effort for tobacco prevention and public health efforts for reducing obesity and alcohol consumption are needed to reduce the cancer burden.     

Prevalence and characteristics of cancer patients receiving care from single vs. multiple institutions

IntroductionPatients may receive cancer care from multiple institutions. However, at the population level, such patterns of cancer care are poorly described, complicating clinical research. To determine the population-based prevalence and characteristics of patients seen by multiple institutions, we used operations data from a state-mandated cancer registry.Methods and materials59,672 invasive cancers diagnosed in 1/1/2010-12/31/2011 in the Greater Bay Area of northern California were categorized as having been reported to the cancer registry within 365 days of diagnosis by: 1) ≥1 institution within an integrated health system (IHS); 2) IHS institution(s) and ≥1 non-IHS institution (e.g., private hospital); 3) 1 non-IHS institution; or 4) ≥2 non-IHS institutions. Multivariable logistic regression was used to characterize patients reported by multiple vs. single institutions.ResultsOverall in this region, 17% of cancers were reported by multiple institutions. Of the 33% reported by an IHS, 8% were also reported by a non-IHS. Of non-IHS patients, 21% were reported by multiple institutions, with 28% for breast and 27% for pancreatic cancer, but 19%% for lung and 18% for prostate cancer. Generally, patients more likely to be seen by multiple institutions were younger or had more severe disease at diagnosis.ConclusionsPopulation-based data show that one in six newly diagnosed cancer patients received care from multiple institutions, and differed from patients seen only at a single institution. Cancer care data from single institutions may be incomplete and possibly biased.     

Active follow-up versus passive linkage with cancer registries for case ascertainment in a cohort

BackgroundAscertaining incident cancers is a critical component of cancer-focused epidemiologic cohorts and of cancer prevention trials. Potential methods: for cancer case ascertainment include active follow-up and passive linkage with state cancer registries. Here we compare the two approaches in a large cancer screening trial.MethodsThe Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial enrolled 154,955 subjects at ten U.S. centers and followed them for all-cancer incidence. Cancers were ascertained by an active follow-up process involving annual questionnaires, retrieval of records and medical record abstracting to ascertain and confirm cancers. For a subset of centers, linkage with state cancer registries was also performed. We assessed the agreement of the two methods in ascertaining incident cancers from 1993 to 2009 in 80,083 subjects from six PLCO centers where cancers were ascertained both by active follow-up and through linkages with 14 state registries.ResultsThe ratio (times 100) of confirmed cases ascertained by registry linkage compared to active follow-up was 96.4 (95% CI: 95.1–98.2). Of cancers ascertained by either method, 86.6% and 83.5% were identified by active follow-up and by registry linkage, respectively. Of cancers missed by active follow-up, 30% were after subjects were lost to follow-up and 16% were reported but could not be confirmed. Of cancers missed by the registries, 27% were not sent to the state registry of the subject’s current address at the time of linkage.ConclusionLinkage with state registries identified a similar number of cancers as active follow-up and can be a cost-effective method to ascertain incident cancers in a large cohort.     

Effects of the length of central cancer registry operations on identification of subsequent cancers and on survival estimates

BackgroundPopulation-based cancer survival analyses have traditionally been based on the first primary cancer. Recent studies have brought this practice into question, arguing that varying registry reference dates affect the ability to identify earlier cancers, resulting in selection bias. We used a theoretical approach to evaluate the extent to which the length of registry operations affects the classification of first versus subsequent cancers and consequently survival estimates.MethodsSequence number central was used to classify tumors from the New York State Cancer Registry, diagnosed 2001–2010, as either first primaries (value = 0 or 1) or subsequent primaries (≥2). A set of three sequence numbers, each based on an assumed reference year (1976, 1986 or 1996), was assigned to each tumor. Percent of subsequent cancers was evaluated by reference year, cancer site and age. 5-year relative survival estimates were compared under four different selection scenarios.ResultsThe percent of cancer cases classified as subsequent primaries was 15.3%, 14.3% and 11.2% for reference years 1976, 1986 and 1996, respectively; and varied by cancer site and age. When only the first primary was included, shorter registry operation time was associated with slightly lower 5-year survival estimates. When all primary cancers were included, survival estimates decreased, with the largest decreases seen for the earliest reference year.ConclusionsRegistry operation length affected the identification of subsequent cancers, but the overall effect of this misclassification on survival estimates was small. Survival estimates based on all primary cancers were slightly lower, but might be more comparable across registries.     

Breast,cervical, and colorectal cancer screening test use in the US territories of Guam,Puerto Rico,and the US Virgin Islands

BackgroundThe United States Preventive Services Task Force (USPSTF) recommends breast, cervical, and colorectal cancer screening among eligible adults, but information on screening use in the US territories is limited.MethodsTo estimate the proportion of adults up-to-date with breast, cervical, and colorectal cancer screening based on USPSTF recommendations, we analyzed Behavioral Risk Factor Surveillance System data from 2016, 2018, and 2020 for the 50 US states and DC (US) and US territories of Guam and Puerto Rico and from 2016 for the US Virgin Islands. Age-standardized weighted proportions for up-to-date cancer screening were examined overall and by select characteristics for each jurisdiction.ResultsOverall, 67.2% (95% CI: 60.6–73.3) of women aged 50–74 years in the US Virgin Islands, 74.8% (70.9–78.3) in Guam, 83.4% (81.7–84.9) in Puerto Rico, and 78.3% (77.9–78.6) in the US were up-to-date with breast cancer screening. For cervical cancer screening, 71.1% (67.6–74.3) of women aged 21–65 years in Guam, 81.3% (74.6–86.5) in the US Virgin Islands, 83.0% (81.7–84.3) in Puerto Rico, and 84.5% (84.3–84.8) in the US were up-to-date. For colorectal cancer screening, 45.2% (40.0–50.5) of adults aged 50–75 years in the US Virgin Islands, 47.3% (43.6–51.0) in Guam, 61.2% (59.5–62.8) in Puerto Rico, and 69.0% (68.7–69.3) in the US were up-to-date. Adults without health care coverage reported low test use for all three cancers in all jurisdictions. In most jurisdictions, test use was lower among adults with less than a high school degree and an annual household income of < $25,000.ConclusionCancer screening test use varied between the US territories, highlighting the importance of understanding and addressing territory-specific barriers. Test use was lower among groups without health care coverage and with lower income and education levels, suggesting the need for targeted evidence-based interventions.     

The validity of cancer information on death certificates in Norway and the impact of death certificate initiated cases on cancer incidence and survival

BackgroundDeath certificates are an important source of information for cancer registries. The aim of this study was to validate the cancer information on death certificates, and to investigate the effect of including death certificate initiated (DCI) cases in the Cancer Registry of Norway when estimating cancer incidence and survival.MethodsAll deaths in Norway in the period 2011–2015 with cancer mentioned on the death certificates were linked to the cancer registry. Notifications not registered from other sources were labelled death certificate notifications (DCNs), and considered as either cancer or not, based on available information in the registry or from trace-back to another source.ResultsFrom the total of 65 091 cancers mentioned on death certificates in the period 2011–2015, 58,425 (89.8%) were already in the registry. Of the remaining 6 666 notifications, 2 636 (2 129 with cancer as underlying cause) were not regarded to be new cancers, which constitutes 4.0% of all cancers mentioned on death certificates and 39.5% of the DCNs. Inclusion of the DCI cases increased the incidence of all cancers combined by 2.6%, with largest differences for cancers with poorer prognosis and for older age groups. Without validation, including the 2 129 disregarded death certificates would over-estimate the incidence by 1.3%. Including DCI cases decreased the five-year relative survival estimate for all cancer sites combined with 0.5% points.ConclusionIn this study, almost 40% of the DCNs were regarded not to be a new cancer case, indicating unreliability of death certificate information for cancers that are not already registered from other sources. The majority of the DCNs where, however, registered as new cases that would have been missed without death certificates. Both including and excluding the DCI cases will potentially bias the survival estimates, but in different directions. This biases were shown to be small in the Cancer Registry of Norway.     

Regional inequalities in cancer care persist in Italy and can influence survival

BackgroundPopulation-based cancer registry studies of care patterns can help elucidate reasons for the marked geographic variation in cancer survival across Italy. The article provides a snapshot of the care delivered to cancer patients in Italy.MethodsRandom samples of adult patients with skin melanoma, breast, colon and non-small cell lung cancers diagnosed in 2003–2005 were selected from 14 Italian cancer registries. Logistic models estimated odds of receiving standard care (conservative surgery plus radiotherapy for early breast cancer; surgery plus chemotherapy for Dukes C colon cancer; surgery for lung cancer; sentinel node biopsy for >1 mm melanoma, vs. other treatment) in each registry compared to the entire sample (reference).ResultsStage at diagnosis for breast, colon and melanoma was earlier in north/central than southern registries. Odds of receiving standard care were lower than reference in Sassari (0.68, 95%CI 0.51–0.90) and Napoli (0.48, 95%CI 0.35–0.67) for breast cancer; did not differ across registries for Dukes C colon cancer; were higher in Romagna (3.77, 95%CI 1.67–8.50) and lower in Biella (0.38, 95%CI 0.18–0.82) for lung cancer; and were higher in Reggio Emilia (2.37, 95%CI 1.12–5.02) and lower in Ragusa (0.27, 95%CI 0.14–0.54) for melanoma.ConclusionsNotwithstanding limitations due to variations in the availability of clinical information and differences in stage distribution between north/central and southern registries, our study shows that important disparities in cancer care persist across Italy. Thus the public health priority of reducing cancer survival disparities will not be achieved in the immediate future.     

Women cancers in India: Incidence,trends and their clinical extent from the National Cancer Registry Programme

BackgroundTo provide a comprehensive assessment of women cancer in India utilizing the systematically collected data on all cancers by the National Cancer Registry Programme (NCRP).MethodsThe study examined 10,2287 cancer cases among women cancers providing cancer burden for major anatomical sites. Aggregated data of 28 PBCRs and 58 HBCRs under NCRP for 2012–16 was analysed for incidence rates, trends, cumulative risk of developing cancer, stage at detection and treatments offered.ResultsStudy results have found region –wide variation of women cancers by indicating highest proportions in western followed by southern region of India. North-Eastern region had lowest proportion. It was observed that breast is highest ranking cancer in most registry areas of urban agglomerations of country while cancer cervix was leading site in registries of rural areas like Barshi (15.3) and Osmanabad &Beed (13.1). States of Mizoram (23.2) and Tripura (9.5) along with Pasighat, Cachar and Nagaland. Median age of occurrence for women for these anatomical sites ranged from 45 to 60 years of age. For cancer breast, cervix and ovary –most cases were detected with regional spread. These findings were different for cancer corpus uteri where registries have reported higher proportions (49.3 %) of localized stage at detection. Loco regional cancers had higher proportions of multimodality treatments.ConclusionStudy provides a foundation for assessing the status of women cancers in the country. Variations between geographies would guide appropriate support for action to strengthen efforts to improve cancer prevention and control in underserved areas of the country. This would facilitate advocacy for better investments and research on women cancers.     

Survival from five common cancers in Georgia, 2015–2019 (CONCORD)

BackgroundPopulation-based cancer survival is a key metric of the effectiveness of health systems in managing cancer. Data from population-based cancer registries are essential for producing reliable and robust cancer survival estimates. Georgia established a national population-based cancer registry on 1 January 2015. This is the first analysis of population-based cancer survival from Georgia.MethodsData were available from the national cancer registry for 16,359 adults who were diagnosed with a cancer of the stomach, colon, rectum, breast (women) or cervix during 2015–2019. We estimated age-specific and age-standardised net survival at one, two and three years after diagnosis for each cancer, by sex.ResultsThe data were of extremely high quality, with less than 2% of data excluded from each dataset. For the patients included in analyses, at least 80% of the tumours were microscopically verified.Age-standardised three-year survival from stomach cancer was 30.6%, similar in men and women. For colon cancer, three-year survival was 60.1%, with survival 4% higher for men than for women. Three-year survival from rectal cancer was similar for men and women, at 54.7%. For women diagnosed with breast cancer, three-year survival was 84.4%, but three-year survival from cervical cancer was only 67.2%.ConclusionEstablishment of a national cancer registry with obligatory cancer registration has enabled the first examination of population-based cancer survival in Georgia. Maintenance of the registry will facilitate continued surveillance of both cancer incidence and survival in the country.     

Escalating burden of breast cancer in southern Thailand: Analysis of 1990–2010 incidence and prediction of future trends

BackgroundThailand is undergoing an epidemiologic transition, with decreasing incidence of infectious diseases and increasing rates of chronic conditions, including cancer. Breast cancer has the highest incidence rates among females both in the southern region Thailand and throughout Thailand. However, there is a lack of research on the epidemiology of this and other cancers.MethodsHere we use cancer incidence data from the Songkhla Cancer Registry to characterize and analyze the incidence of breast cancer in Southern Thailand. We use joinpoint analysis, age-period-cohort models and nordpred analysis to investigate the incidence of breast cancer in Southern Thailand from 1990 to 2010 and project future trends from 2010 to 2029.ResultsWe found that age-adjusted breast cancer incidence rates in Southern Thailand increased by almost 300% from 1990 to 2010 going from 10.0 to 27.8 cases per 100,000 person-years. Both period and cohort effects played a role in shaping the increase in incidence. Three distinct incidence projection methods consistently suggested that incidence rates will continue to increase in the future with incidence for women age 50 and above increasing at a higher rate than for women below 50.ConclusionsTo date, this is the first study to examine Thai breast cancer incidence from a regional registry. This study provides a basis for future planning strategies in breast cancer prevention and to guide hypotheses for population-based epidemiologic research in Thailand.     

Cervical cancer screening in the National Breast and Cervical Cancer Early Detection Program (NBCCEDP) in four US-Affiliated Pacific Islands between 2007 and 2015

BackgroundCervical cancer incidence in the US-Affiliated Pacific Islands (USAPIs) is double that of the US mainland. American Samoa, Commonwealth of Northern Mariana Islands (CNMI), Guam and the Republic of Palau receive funding from the Centers for Disease Control (CDC) National Breast and Cervical Cancer Early Detection Program (NBCCEDP) to implement cervical cancer screening to low-income, uninsured or under insured women. The USAPI grantees report data on screening and follow-up activities to the CDC.Materials and methodsWe examined cervical cancer screening and follow-up data from the NBCCEDP programs in the four USAPIs from 2007 to 2015. We summarized screening done by Papanicolaou (Pap) and oncogenic human papillomavirus (HPV) tests, follow-up and diagnostic tests provided, and histology results observed.ResultsA total of 22,249 Pap tests were conducted in 14,206 women in the four USAPIs programs from 2007–2015. The overall percentages of abnormal Pap results (low-grade squamous intraepithelial lesions or worse) was 2.4% for first program screens and 1.8% for subsequent program screens. Histology results showed a high proportion of cervical intraepithelial neoplasia grade 2 or worse (57%) among women with precancers and cancers. Roughly one-third (32%) of Pap test results warranting follow-up had no data recorded on diagnostic tests or follow-up done.ConclusionThis is the first report of cervical cancer screening and outcomes of women served in the USAPI through the NBCCEDP with similar results for abnormal Pap tests, but higher proportion of precancers and cancers, when compared to national NBCCEDP data. The USAPI face significant challenges in implementing cervical cancer screening, particularly in providing and recording data on diagnostic tests and follow-up. The screening programs in the USAPI should further examine specific barriers to follow-up of women with abnormal Pap results and possible solutions to address them.     

Validity of initial cancer diagnoses in the Diagnosis Procedure Combination data in Japan

BackgroundIn Japan, the Diagnosis Procedure Combination (DPC) data have been used as a nationwide administrative hospital discharge database for clinical studies. However, few studies have evaluated the validity of recorded diagnoses of cancer in the database.MethodsWe compared the DPC data with hospital-based cancer registries in Osaka Prefecture, Japan to assess the validity of the recorded cancer diagnoses in the DPC data. Fifteen types of cancer were included in the analysis. Cancer stage with tumor-node-metastasis (TNM) classification was assessed for eight cancer types with >400 patients. We evaluated concordance and positive predictive value of cancer diagnosis, and concordance of cancer stage between the DPC data and the hospital-based cancer registry.ResultsIn total, we identified 29,180 eligible patients. The five types of cancer with the highest number of patients were as follows: 6,765 (23.2 %) colorectal, 6,476 (22.2 %) stomach, 4,862 (16.7 %) breast, 4,445 (15.2 %) lung, and 2,257 (7.7 %) liver. Concordance of diagnosis ranged from 63.9 %–99.5 %, and twelve of the fifteen types of cancers had concordance of over 90 %. Positive predictive values of diagnosis ranged from 86.8 %–100 %. Regarding cancer stage, the overall degree of concordance was 67.2 % in all patients and the concordance was over 70 % in four types of cancers.ConclusionsThe DPC data had high validity of cancer diagnosis. However, the potential impact of the misclassifications and low concordance in cancer stage among specific type of cancers in the DPC data should be considered.     

Bias in survival estimates created by a requirement for consent to enter a clinical breast cancer registry

BackgroundA requirement for consent for inclusion may bias the results from a clinical registry. This study gives a direct measure of this bias, based on a population-based clinical breast cancer registry where the requirement for consent was removed after further ethical review and data could be re-analysed.MethodsIn Auckland, New Zealand, the population-based clinical breast cancer registry required written patient consent for inclusion from 2000-2012. A subsequent ethical review removed this requirement and allowed an analysis of consented and non-consented patients. Kaplan-Meier survival to 10 years (mean follow-up 5.1 years, maximum 13.9 years), demographic and clinical characteristics were compared. Of 9244 women with invasive cancer, 926 (10.4%) were not consented, and of 1642 women with ductal carcinoma in situ, 245 (14.9%) were not consented.ResultsSurvival was much higher for consenting patients; invasive cancer, 5 year survival 83.2% (95% confidence limits 82.2–84.1%) for consenting patients, 57.1% (53.0–60.9%) for non-consenting, and 80.8% in all patients. Analyses based only on consenting patients overestimate survival in all patients by around 2% at 2, 5, and 10 years. Non-consented patients were older, more often of Pacific ethnicity, had fewer screen-detected cancers, and more often had metastatic disease; they less frequently had primary surgery or systemic treatments.ConclusionData from a registry requiring active consent gives an upward bias in survival results, as non-consenting patients have more extensive disease, less treatment, and lower survival. To give unbiased results active consent should be not required in a clinical cancer registry.     

Measuring the effect of including multiple cancers in survival analyses using data from the Canadian Cancer Registry

Background: In survival analyses using cancer registry data, second and subsequent primary cancers diagnosed in individuals are typically excluded. However, this approach may lead to biased comparisons of survival between cancer registries, or over time within a single registry. Purpose: To examine the impact of including multiple primary cancers in the derivation of survival estimates using data from a population-based national cancer registry. Methods: Five-year relative survival estimates for persons aged 15–99 years at diagnosis were derived using all eligible primary cases from the Canadian Cancer Registry (CCR)—a population-based registry containing information on cases diagnosed from 1992 onward—and then again using first primary cases only. Any pre-1992 cancer history of persons on the CCR was obtained by using auxiliary information. Results: The inclusion of multiple cancers resulted in lower estimates of 5-year relative survival for virtually all cancers studied. The effect was somewhat attenuated by age-standardization (e.g., from 1.3% to 1.0% for all cancers combined), and was greatest for bladder cancer (?2.4%) followed by oral cancer (?1.9%)—cancers that had the first and third lowest proportions of first cancers, respectively. For the majority of cancers the difference was less than 1.0%. Cancers for which there was virtually no difference (e.g., lung, pancreatic, ovarian and liver) tended to be those with a poor prognosis. Conclusion: Inclusion of second and subsequent primary cancers in the analysis tended to lower estimates of relative survival, the extent of which varied by cancer and age and depended in part on the proportion of first primary cancers.     

Marked increase in breast cancer incidence in young women: A 10-year study from Northern Iran, 2004–2013

IntroductionBreast cancer is the most frequent cancer among women worldwide. Breast cancer incidence in young women is a health issue of concern, especially in middle-income countries such as Iran. The aim of this study is to report the breast cancer incidence variations in Golestan province, Iran, over a 10-year period (2004–2013).MethodsWe analyzed data from the Golestan Population-based Cancer Registry (GPCR), which is a high-quality cancer registry collecting data on primary cancers based on standard protocols throughout the Golestan province. Age-standardized incidence rates (ASRs) and age-specific incidence rates per 100,000 person-years were calculated. Time trends in ASRs and age-specific rates were evaluated using Joinpoint regressions. The average annual percentage change (AAPC) with correspondence 95% confidence intervals (95%CIs) were calculated.ResultsA total of 2106 new breast cancer cases were diagnosed during the study period. Most cases occurred in women living in urban areas: 1449 cases (68%) versus 657 cases (31%) in rural areas. Statistically significant increasing trends were observed over the 10-year study period amongst women of all ages (AAPC = 4.4; 95%CI: 1.2–7.8) as well as amongst women in the age groups 20–29 years (AAPC = 10.0; 95%CI: 1.7–19.0) and 30–39 years (AAPC = 5.1; 95%CI: 1.4–9.0).ConclusionThe incidence of breast cancer increased between 2004 and 2013 in Golestan province amongst all age groups, and in particular amongst women aged 20–39 years. Breast cancer should be considered a high priority for health policy making in our community.     

Impact of geographic area level on measuring socioeconomic disparities in cancer survival in New South Wales,Australia: A period analysis

BackgroundArea-based socioeconomic measures are widely used in health research. In theory, the larger the area used the more individual misclassification is introduced, thus biasing the association between such area level measures and health outcomes. In this study, we examined the socioeconomic disparities in cancer survival using two geographic area-based measures to see if the size of the area matters.MethodsWe used population-based cancer registry data for patients diagnosed with one of 10 major cancers in New South Wales (NSW), Australia during 2004–2008. Patients were assigned index measures of socioeconomic status (SES) based on two area-level units, census Collection District (CD) and Local Government Area (LGA) of their address at diagnosis. Five-year relative survival was estimated using the period approach for patients alive during 2004–2008, for each socioeconomic quintile at each area-level for each cancer. Poisson-regression modelling was used to adjust for socioeconomic quintile, sex, age-group at diagnosis and disease stage at diagnosis. The relative excess risk of death (RER) by socioeconomic quintile derived from this modelling was compared between area-units.ResultsWe found extensive disagreement in SES classification between CD and LGA levels across all socioeconomic quintiles, particularly for more disadvantaged groups. In general, more disadvantaged patients had significantly lower survival than the least disadvantaged group for both CD and LGA classifications. The socioeconomic survival disparities detected by CD classification were larger than those detected by LGA. Adjusted RER estimates by SES were similar for most cancers when measured at both area levels.ConclusionsWe found that classifying patient SES by the widely used Australian geographic unit LGA results in underestimation of survival disparities for several cancers compared to when SES is classified at the geographically smaller CD level. Despite this, our RER of death estimates derived from these survival estimates were generally similar for both CD and LGA level analyses, suggesting that LGAs remain a valuable spatial unit for use in Australian health and social research, though the potential for misclassification must be considered when interpreting research. While data confidentiality concerns increase with the level of geographical precision, the use of smaller area-level health and census data in the future, with appropriate allowance for confidentiality     

Characteristics of cases with unknown stage prostate cancer in a population-based cancer registry

BackgroundThe New South Wales Central Cancer Registry (NSW CCR) is the only population-based cancer registry in Australia that has routinely collected summary stage at diagnosis since its inception in 1972. However, a large proportion of prostate cancer cases have “unknown” stage recorded by the registry. We investigated the characteristics of prostate cancer cases with “unknown” stage recorded by the NSW CCR, and examined survival for this group.MethodsData were obtained from the NSW CCR for all first primary prostate cancer cases diagnosed in 1999–2007. Summary stage was recorded as localised, regional, distant or “unknown”. Associations between disease stage and patient characteristics (age, place of residence at diagnosis, year of diagnosis and country of birth) and prostate cancer specific survival were investigated using multivariable logistic regression and Cox proportional hazards models respectively.ResultsOf 39 852 prostate cancer cases, 41.8% had “unknown” stage recorded by the NSW CCR. This proportion decreased significantly over time, increased with increasing age at diagnosis and was higher for those living in socio-economically disadvantaged areas. The proportion with “unknown” stage varied across area health services. Prostate cancer specific survival for cases with “unknown” stage was significantly poorer than for those with localised stage but better than for those with regional or distant stage.ConclusionsResearchers or others using cancer registry stage data to examine prostate cancer outcomes need to consider the differences between cases with “unknown” stage at diagnosis and those with known stage recorded by the registry, and what impact this may have on their results.