Esophageal and gastric cancer incidence trends in Golestan, Iran: An age-period-cohort analysis 2004 to 2018.

Golestan province in the northeast of Iran is part of the Asian esophageal cancer belt and is known as a high-risk area for esophageal (EC) and gastric cancers (GC). Data on incident cases of EC and GC during 2004 to 2018 were obtained from the Golestan Population-based Cancer Registry (GPCR). The age-standardized incidence rates (ASRs) were calculated and presented per 100 000 person-years. The estimated annual percentage change (EAPC) with 95% confidence interval (95% CI) were calculated. We also fitted age-period-cohort (APC) models to assess nonlinear period and cohort effects as incidence rate ratios (IRRs). Overall, 3004 new cases of EC (ASR = 15.7) and 3553 cases of GC (ASR = 18.3) were registered in the GPCR. We found significant decreasing trends in incidence rates of EC (EAPC = -5.0; 95% CI: -7.8 to -2.2) and less marked nonsignificant trends for GC (EAPC = -1.4; 95% CI: -4.0 to 1.4) during 2004 to 2018. There was a strong cohort effect for EC with a consistent decrease in the IRR across successive birth cohorts, starting with the oldest birth cohort (1924; IRR = 1.9 vs the reference birth cohort of 1947) through to the most recent cohort born in 1988 (IRR = 0.1). The marked declines in EC incidence rates in Golestan relate to generational changes in its underlying risk factors. Despite favorable trends, this population remains at high risk of both EC and GC. Further studies are warranted to measure the impact of the major risk factors on incidence with a view to designing effective preventative programs.

Breast cancer incidence trends in Golestan, Iran: An age-period-cohort analysis by ethnic region, 2004-2018.

BACKGROUND: We aimed to examine the effects of age, diagnosis year (calendar period) and birth year (cohort) on the incidence trends of breast cancer among Golestan women, Northeast Iran, 2004-2018. METHODS: Incidence data were obtained by residential status (urban/rural) and ethnic region (Turkmens/non-Turkmens). We calculated age-standardized incidence rates (ASRs) per 100,000 person-years. The estimated annual percentage change (EAPC) were calculated, and age-period-cohort (APC) models fitted to assess non-linear effects of period and cohort as incidence rate ratios (IRRs). RESULTS: The total number of female breast cancer cases in Golestan, 2004-2018, were 3853, with an overall ASR of 31.3. We found higher rates in urban population (40.5) and non-Turkmens region (38.5) compared to rural area (20.8) and Turkmens region (20.2), respectively. There were increasing trends in incidence rates overall (EAPC= 4.4; 95%CI: 2.2, 6.7), with greater changes in rural areas (EAPC=5.1), particularly among non-Turkmens (EAPC=5.8). The results of the APC analysis indicate the presence of significant non-linear cohort effects with increasing IRRs across successive birth cohorts (IRR=0.1 and IRR= 2.6 for the oldest and the youngest birth cohorts vs. the reference birth cohort, respectively). CONCLUSION: We found increasing trends in breast cancer incidence among Golestan women over the study period, with disparities in patterns and trends by residence area and ethnic region. The observed cohort effects suggest an increasing prevalence of key risk factors for breast cancer in this Iranian population. Further investigations are warranted to clarify the relationships between determinants such as reproductive factors and ethnicity in the region.

Temporal and Geographical Trends of Incidence of Thyroid Cancer in Golestan, Iran, 2004-2013.

BACKGROUND: Thyroid cancer is the most common type of endocrine cancer. We aimed to determine the incidence rates of thyroid cancer across a 10-year period (2004-2013) in Golestan, Iran. METHODS: We obtained the thyroid cancer data from Golestan Population-Based Cancer Registry (GPCR). Age-standardized incidence rates (ASR) were calculated and reported per 100000 person-years. The Joinpoint software was used to assess time trends, and average annual percent changes (AAPCs) and their corresponding 95% confidence intervals (CIs) were reported. RESULTS: Of 326 registered patients, 83 (25.5%) were men and 243 (74.5%) were women. The mean age was 51.3 and 42.6 years for males and females, respectively. Overall, the ASR of thyroid cancer was 2.2 per 100000 person-year (AAPC = 2.76; 95% CI: -3.68 to 9.64). The test of co-incidence showed a statistically significant difference in the incidence of thyroid cancer between men (1.3) and women (3.2) (P < 0.001). According to our results, the ASR of thyroid cancer in western parts of Golestan is higher, including Gorgan and Aliabad cities. CONCLUSION: Increasing trends in incidence rates of thyroid cancer were found in the Golestan province during the study period, especially in women. We found significantly higher rates of thyroid cancer in women. Geographical diversities were seen in incidence rates of thyroid cancer in the Golestan province. Our results may be helpful for designing further researches to investigate the epidemiological aspects of thyroid cancer in the Golestan province.

Building a Cancer Biobank in a Low-Resource Setting in Northern Iran: the Golestan Cancer Biobank.

BACKGROUND: We aim to present the development and the initial results of the Golestan Cancer Biobank (GoCB), in a low resource setting in northern Iran. METHODS: The GoCB protocol and its standard operation procedures (SOP) were developed according to internationally accepted standards and protocols with some modifications considering the limited resources in our setting. The main biological samples collected by the GoCB include blood sample, urine sample, fresh endoscopy tissue sample, fresh surgical tissue sample and formalin fixed paraffin embedded (FFPE) tissue sample. The GoCB collects patients' demographic data, tumor characteristics as well as data on risk factors. We developed a specific GoCB software for management of patient data and biological sample information. The GoCB dataset is annually linked with the Golestan cancer registry dataset to add complementary data (e.g., survival data). RESULTS: The GoCB started collection of data and biological samples in December 2016. By November 2020, a total number of 1217 cancer patients participated in the GoCB. The majority of the GoCB participants (n = 942, 77%) were those with gastrointestinal and breast cancers. Data on risk factors were successfully collected in 684 (56.2%) of the participants. Overall, 3563 samples were collected from the GoCB participants and 730 samples were used in 7 national and international research projects. CONCLUSION: We considered specific strategies to overcome major limitations, especially budget shortage, in the development and maintenance of a cancer-specific biological repositories in our setting. The GoCB may be considered as a model for the development of biobank in low- and middle-income countries (LMICs).

Descriptive Epidemiology of Lymphoma in Northern Iran: Results from the Golestan Registry 2004-2013.

BACKGROUND: There is currently little known about the epidemiology of lymphomas in Iran. The aim of this paper is to describe the geographic and time variations in incidence rates of lymphomas in the Golestan province between 2004 and 2013. METHODS: The Golestan Population-based Cancer Registry (GPCR) routinely registers primary cancer patients from all sources (e.g. pathology centers, hospitals, etc.) throughout the Golestan province. We obtained data on newly-diagnosed lymphomas in Golestan during 2004-2013 from the GPCR dataset. Crude rates and age standardized incidence (ASR) rates (per 100000) of lymphomas were estimated, joinpoint regression was used to quantify incidence trends and average annual percent changes (AAPCs) were calculated. RESULTS: In total, 898 new cases of lymphoma were registered in the GPCR during 2004-2013. The ASR of Hodgkin lymphoma (HL) was 1.5 and 1.1 in males and females, respectively, while corresponding non-Hodgkin lymphoma (NHL) rates were greater, at 6.5 and 3.4 in males and females, respectively. Our results indicated a significant difference in the trends of HL between males (AAPC = -3.2) and females (AAPC = 3.6, P value = 0.001). The incidence rates of lymphoma were considerably higher in the urban population (ASR = 7.3) compared to those residing in rural areas (ASR = 5.3, P value = 0.054). We also found higher incidence rates for both HL and NHL in the western parts of the Golestan province. CONCLUSION: The incidence rates of lymphoma in the Golestan province are relatively high and vary geographically, with a higher incidence observed in the western area. Such differences may reflect unknown lifestyle and environmental determinants linked to ethnic susceptibility differing between the two areas.

Increasing trends of lung cancer in Golestan province, Northern Iran (2004-2016).

INTRODUCTION: We aimed to present the time trends and geographical distribution of lung cancer in Golestan province, a high-risk area for pulmonary tuberculosis (TB) in Northern Iran (2004-2016). METHODS: Data on incident primary lung cancers were obtained from the Golestan population-based cancer registry. The data were analyzed by CanReg-5 software to calculate the age-standardized incidence rates (ASRs). We used Joinpoint software for time trend analysis. Average annual percent changes were calculated. The contribution of population aging, population growth and risk to the overall changes in incidence of lung cancer were determined using partitioning analysis. RESULTS: Overall, 1829 cases of lung cancer were registered by the GPCR during 2004-2016, of which 1274 (69.7%, ASR in 2016 = 21.3) were men and 555 (30.3%, ASR in 2016 = 11.4) were women. The results of Joinpoint regression suggested a significant increasing trend in incidence of lung cancer in Golestan province during 2004 and 2016 (AAPC = 3.74; p-value = 0.01) with more prominent increasing in rural population (AAPC = 4.93; p-value<0.01). The number of new cases of lung cancer increased by 131.6% (from 98 in 2004 to 227 in 2016), of which 34.1%, 22.3% and 75.3% were due to population size, population aging and risk, respectively. Hot points of lung cancer were found in western parts of the Golestan. CONCLUSION: With high incidence rates and increasing trends of lung cancer, further studies are warranted to clarify the role of TB and other risk factors on its burden in this population.

Recent cancer incidence trends and short-term predictions in Golestan, Iran 2004-2025.

BACKGROUND: We examine recent trends in the major cancers occurring in the Golestan province, a high-risk region for upper gastrointestinal cancers in Northern Iran, and provide short-term cancer predictions of the future cancer burden. METHODS: New cancer cases diagnosed in Golestan 2004-2016 were obtained from the Golestan population-based cancer registry (GPCR) database, and age-standardized rates by cancer site, year and sex calculated per 100,000 person-years. Using IARC's DepPred package we fitted time-linear age-period models to the available GPCR data to predict the cancer incidence burden in the year 2025. We calculated the contribution of demographic changes versus changes in risk to the overall changes in incidence from 2016 to 2025. RESULTS: The number of new cancer cases (excluding non-melanoma skin cancers) in 2025 is predicted to increase by 61.3% from 2678 cases in 2016 to 4319 cases. While a 17.6% reduction in the number of esophageal cancer cases is predicted by 2025, the number of new cases for each of the remaining major cancers is predicted to increase over the next decade, including cancers of the stomach (a 36.1% increase from 2016 to 2025), colorectum (56.2%), lung (67.8%), female breast (93.2%), prostate (101.8%) and leukemia (96.1%). The changes in the population structure and risk contributed 37.8% and 23.5% respectively, to the overall increase in incidence. CONCLUSION: Other than for the major upper gastrointestinal cancer types, the incidence rates of common cancers observed in the province are on the rise, reinforcing the need for continuous surveillance, as well as the design and implementation of effective cancer control programs.

Temporal and geographical variations in colorectal cancer incidence in Northern Iran 2004-2013.

INTRODUCTION: Colorectal cancer (CRC) is one of the most common cancers in the Golestan province, Northern Iran. The purpose of this study is to describe colorectal cancer incidence patterns and trends in the province 2004-2013. METHODS: Data on CRC cases were obtained from the Golestan Population-based Cancer Registry (GPCR). The GPCR is a high-quality cancer registry that collects data on primary cancers according to internationally accepted standard protocols. Age-standardized Incidence rates (ASR) were calculated and the 10-year trend quantified using the average annual percentage change (AAPC) from Joinpoint regressions. RESULTS: The overall ASR of CRC were higher in men (14.8 per 100,000 person-years) and the urban populations (35.4), relative to women (11.5) and the rural populations (17.1), respectively. The overall incidence rate was observed to significantly increase 2004-2013 in men (AAPC = 7.3; 95%CI: 2.9-11.8) and women (AAPC = 6.6; 95%CI: 2.7-10.6). The analysis also showed that urban areas (AAPC = 8.1; 95%CI: 2.4-14.1) had a relatively more rapid increase in rates compared to rural areas (AAPC = 6.9; 95%CI: 2.2-11.7). CONCLUSIONS: CRC incidence rates in Golestan have been rising during the most recent decade, with a higher incidence and more rapid increases among men and the urban populations. The underlying risk factors should be assessed in the context of developing CRC prevention interventions in Golestan.

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

INTRODUCTION: Breast 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). METHODS: We 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. RESULTS: A 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). CONCLUSION: The 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.

Completeness and Accuracy of Death Registry Data in Golestan, Iran.

BACKGROUND: We aimed to evaluate completeness and accuracy of the Golestan Death Registry (GDR) to identify cancer-related causes of death (CCoD). METHODS: The GDR data (2004-2015) were compared with cancer data collected from clinical/pathological sources (the considered gold standard) by the Golestan Population-Based Cancer Registry (GPCR). Using a linkage method, matched cases, including subjects with CCoD and those with ill-defined cause of death (ICoD) (garbage codes), were identified and entered into the final analysis as study subjects. The completeness (percentage of study subjects with CCoD) and accuracy (number of subjects with correct CoD from the total number of study subjects) of the GDR were calculated. RESULTS: In total, 3,766 matched cases were enrolled. Overall, the completeness and accuracy of the GDR for identifying CCoD were 92.7% and 53.2%, respectively. There were variations by cancer site and age group, with completeness and accuracy highest for brain cancer (96.3%) and leukaemia (79.8%) while the lowest accuracy was observed for colorectal cancer (29.9%). The completeness and accuracy of GDR was higher in patients aged under 60 years (95.7% and 53.6%, respectively). We also found higher completeness (93.7%) and accuracy (55.8%) in residents of rural areas. CONCLUSION: Linkage of death registry data with cancer registry data can be a significant resource for evaluating quality of the death registry data. Our findings suggested that completeness of the GDR for identifying CCoD is reasonable, but accuracy is relatively low. Access to clinical and pathological data from other sources and enhanced training of death certifiers can improve the present situation.

Marked increase in the incidence rate of esophageal adenocarcinoma in a high-risk area for esophageal cancer.

BACKGROUND: Esophageal cancer (EC) is the eighth common cancer worldwide. Esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAD) are the most common histologic types of EC. Many recent reports showed an increasing trend in EAD and a decreasing trend in ESCC in many Western countries. Golestan Province in northeastern Iran has been known as a high-risk area for EC. The aim of this study was to describe the time trend of EAD in this area between 2000-2009. METHODS: Data on cancer cases were obtained from Golestan Population-based Cancer Registry. Analysis was done using Joinpoint software. To examine the incidence trends, the annual percent change was calculated. The possibilities of anatomic and histologic misclassification were considered by assessing the trend of ESCC and gastric adenocarcinoma.  RESULTS: A total number of 1186 histologically-confirmed EC cases were recruited. The incidence rate of EAD showed a significant increasing trend. There was no significant trend in the incidence of ESCC during the study period. A significant increase in the incidence rate of gastric adenocarcinoma   was observed during the period of 2000-2005, followed by a plateau during the period of 2005-2009. CONCLUSIONS: We found a significant increasing trend in the incidence rate of EAD. We find no evidence to support an alternative explanation including anatomic and histologic misclassification. So, the observed rise in the incidence of EAD seems to be real. Therefore, designing and implementation of control programs, including control of preventable risk factors of EAD, should be considered in this high- risk area.