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.

Colorectal cancer incidence trends in Golestan, Iran: An age-period-cohort analysis 2004-2018

BACKGROUND

We investigated the effects of factors including age, birth year (cohort) and diagnosis year (period) on colorectal cancer (CRC) incidence trends in Golestan, Northeast of Iran, 2004-2018.

METHODS

We obtained data on incidence cases of CRC from the Golestan Population-based Cancer Registry by sex and area of residence (urban/rural). Age-standardized incidence rates (ASRs) were calculated using the World standard population and presented per 100,000 person-years. We calculated the estimated annual percentage change (EAPC) with 95 % confidence intervals (95 % CI) fitted age-period-cohort (APC) models to assess non-linear period and cohort effects as incidence rate ratios (IRRs).

RESULTS

Overall, 2839 new cases of CRC (ASR = 13.7) were registered in the GPCR over 2004-2018. Our findings suggested significantly increasing trends in CRC incidence rates from 2004 to 2018 (EAPC = 3.7; 95%CI: 0.4, 7.1), with the greatest changes occurring in rural women (EAPC= 4.7; 95%CI: 0.4, 9.2). We observed a strong cohort effect with a consistent increase in the IRR across successive birth cohorts, starting with the oldest birth cohort (1924) (IRR= 0.1 versus the reference birth cohort of 1955) through to the most recent cohort born in 1983 (IRR= 1.9). The largest cohort effects were found among rural females (IRR = 0.0, and IRR = 2.5 for the oldest and the youngest birth cohorts vs. the reference birth cohort, respectively).

CONCLUSION

The increasing trends in CRC rates in Golestan are largely driven by generational changes in exposure to underlying risk factors. Further investigations are warranted to deliver effective prevention strategies for the control of CRC in Golestan.

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.

Development of an online cancer data collection and processing tool for population-based cancer registries in a low-resource setting: The CanDCap experience from Golestan, Iran

BACKGROUND

Golestan Population-based Cancer Registry (GPCR) with more than 15-years experiences developed an in-house online software called Cancer Data Collection and Processing (CanDCap) to improve its data collection operations from the conventional offline method to new online method. We aimed to report the methods and framework that GPCR applied to design and implementation of the CanDCap.

METHODS

CanDCap was designed based on International Agency for Research on Cancer (IARC) protocols and standards and according to the GPCR workflow. CanDCap has two parts including a web-based online part for data collection and a windows-based part for data processing consisting of quality control and deduplication of repeated records. Questionnaire for User Interface Satisfaction (QUIS) was used in order to assess user interaction satisfaction.

RESULTS

CanDCap was implemented in 2018 and could improve the quality of the GPCR data during its first three years of activity (2018-2020), during which about 9,000 records were registered. The coverage for optional items including national ID, father name, address and telephone number were improved from 23 %, 32 %, 83 % and 82 % in conventional offline method (2015-2017) to 83 %, 81 %, 87 %, and 90 % after using the CanDCap (2018-2020), respectively. The timeliness was also improved from 4 years to 2 years. Overall, user interaction satisfaction was acceptable (7.8 out of 9).

CONCLUSION

CanDCap could resulted in improvement in data quality and timeliness of the GPCR as a cancer registry unit with limited resources. It has the potential to be considered as a model for population-based cancer registries in lower-resource settings.

Analysis of Competing Risks of Causes of Death in Cancer Patients from Golestan, Iran over Twelve Years (2004-2016)

Background:

Cancer-related causes of death (cancer CoD) are the main etiologies of death in cancer patients. Recent increase in survival rates of cancer patients resulted in higher risk of dying from causes other than cancer, called competing causes of death (competing CoD). We aim to characterize competing CoD among cancer patients in Golestan province, Northern Iran.

Methods:

Data on cancer incidence was obtained from the Golestan population-based cancer registry (GPCR) dataset. Data on causes of death was obtained from the Golestan death registry (GDR) dataset. Using a linkage method between the GPCR and GDR dataset, we prepared the study dataset including data on vital status and causes of death in our cancer patients. The proportions of cancer CoD and competing CoD were calculated. Multivariate logistic regression analysis was considered to assess the relationship between competing CoD and other variables.

Results:

Overall, 4,184 cancer patients died in the study population, including 2,488 men (59.9%). Cause of death in 3,455 cases was cancer and 729 cases (17.4%) died due to competing CoD. Ischemic heart disease (40.7%) was the most common competing CoD in our population. Higher survival rate was the strongest variable related to the competing CoD (adjusted OR=1.91; 95%CI: 1.61-2.26). Residence area, age group and year of death were other indicators of competing CoD in our population.

Conclusion:

Our results suggest high rates of competing CoD in our cancer patients. Competing CoD should be mentioned in cancer control planning both in clinical practice as well as in public health policy making.

Detection Rate of Colorectal Polyps in Symptomatic Candidates of Colonoscopy: When Should We Do a Total Colonoscopy?

BACKGROUND The incidence of colorectal cancer is increasing in the northeast of Iran. Colorectal polyps are among the proposed risk factors noted, especially in the elder population. This study was designed to study the diagnosed cases of intestinal polyps detected from 2011 to 2016 in the northeast of Iran. METHODS The population consisted of symptomatic candidates referred to the colonoscopy center in Gorgan city. Based on the available colonoscopy and pathology reports, 1706 cases were enrolled after the exclusion of cases without sufficient data. RESULTS Among 1709 (55.5% males and 44.5% females) cases, 1405 cases with 1912 polyps were detected. Among them, 345 (25%) aged less than 50 years. Tubular adenoma (N = 826, 43.2%) and hyperplastic polyps (N = 519, 27.1%) were the top two histological findings. Out of 1405 patients with polyps, 660 (39.6%) polyps were detected in proximal colon (15.6% in proximal and 24% in both proximal and distal). Malignancies were detected in 13.2% (0.8% malignant polyps and 12.4% malignant masses). CONCLUSION A considerable number of colorectal adenomas in proximal colon and in patients younger than 50 years old, suggesting to schedule colorectal cancer screening from at least 10 years younger and continuing colonoscopy up to the proximal area.

Primary Liver Cancer in Golestan Province, Northeastern Iran: 13-Year Experience of Golestan Population-Based Cancer Registry (GPCR)

BACKGROUND

Liver cancer (LC) is among the most common and fatal cancers worldwide. A four-fold increasing trend is reported for LC age-standardized mortality rate (ASMR) in Iran within 1990-2015. In the present study, we aimed to report the incidence rate of LC during the 13-year establishment of the Golestan population-based cancer registry (GPCR).

METHODS

Age-standardized incidence rate (ASIR) per 100000 person-years was calculated using CanReg5 software. The Joint point regression analysis was used to assess the temporal trends in incidence rate of LC.

RESULTS

During the study period, GPCR registered 575 of LC cases, of which 373 (64.9%) were men and 297 (51.6%) lived in rural areas. The mean (SD) age of LC in men and women were 60.3 (17.2) and 58.0 (17.1), respectively. The ASIR of LC was significantly higher in men than women (4.7 vs. 2.6; P value<0.01) and a minimal increasing trend in LC incidence was observed in both sexes. The incidence rate of LC was significantly higher in rural areas compared to the urbans (3.91 vs. 3.40; P value=0.04). In the last 13 years, rural population had a significant increasing trend in ASIR of LC (average annual percent change [AAPC]=7.85, P value=0.005).

CONCLUSION

LC was more prevalent in men among both urban and rural populations. The results showed a significant increasing trend in rural areas that requires Golestan health care system to take action in controlling the burden of LC in rural areas.

Persian Medicine “Sahj” in Ulcerative Colitis Remedy: A Before-and-After Cinical Trial

Ulcerative colitis (UC) is an inflammatory bowel disease and its etiology has not fully understood in conventional medicine. It also influences the quality of life as a result of its recurrence and progressive clinical course, then, it has been considered an important public health concern. This study aimed to evaluate the impact of prescription therapy based on the Persian Medicine as a complementary treatment for the mitigation of the symptoms of UC as well as improvement in the disease severity. A total of 30 UC patients with an age range of 15-70 years participated in this clinical trial. They were treated with the “Sahj” capsule containing: Curcuma longa L., Punica granatum L., and Terminalia chebula Retz. for 4 weeks. The “Sahj” capsule was prepared based on the Persian Medicine resources. The bowel frequency at day/night, urgency of defecation, general health, and blood in stool were assessed pre/post intervention and the results were compared before and after the clinical trial. The “Sahj” capsule significantly enhanced the clinical findings. There was a significant increase in simple clinical colitis activity index (SCCAI) score in response to the prescription of the “Sahj” capsule (7.73 ± 1.98 before and 4.30 ± 1.12 after the trial) in which general health condition of patients was increased by 50% after the clinical trial. Bowel frequency at day was remarkably decreased by totally 15 patients with the scores of 1, 2 and 3 were enrolled to score 0. Also, bowel frequency at night was not statically significant (p = 0.267) in spite of 7 patients were improved their score (changed their score from 2 to 1).  Urgency of defecation (p 0.003) and blood in stool (p 0.0001) were significantly decreased compared with pre-intervention stage. These findings suggest an appropriate complementary treatment to reduce the symptoms of ulcerative colitis. However, further studies with larger sample size are warranted to assess the efficacy and safety of the “Sahj” capsule in the treatment of UC.

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).

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.

Trends in the Incidence of Stomach Cancer in Golestan Province, a High-risk Area in Northern Iran, 2004-2016

BACKGROUND

We aimed to present the temporal and geographical trends in the incidence of stomach cancer in the Golestan province, a high-risk area in Northern Iran.

METHODS

This study was conducted on stomach cancer cases registered in the Golestan Population-based Cancer Registry (GPCR) during 2004-2016. Age-standardized incidence rates (ASRs) per 100000 person-years were calculated. The Joinpoint regression analysis was used to calculate the average annual percent changes (AAPC). We also calculated the contribution of population aging, population size and risk to the overall changes in incidence rates.

RESULTS

Overall, 2964 stomach cancer patients were registered. The ASR of stomach cancer was significantly higher in men (26.9) than women (12.2) (P<0.01). There was a significant decreasing trend in incidence of stomach cancer in men (AAPC=-1.80, 95% CI: -3.30 to-0.28; P=0.02). We found a higher ASR of stomach cancer in the rural (21.4) than urban (18.1) (P=0.04) population, as well as a significant decreasing trend in its rates (AAPC=-2.14, 95% CI: -3.10to-1.17; P<0.01). The number of new cases of stomach cancer increased by 22.33% (from 215 in 2004 to 263 in 2016), of which 18.1%, 25.1% and -20.9% were due to population size, population aging and risk, respectively. Our findings suggest a higher rate for stomach cancer in eastern areas.

CONCLUSION

We found high incidence rates as well as temporal and geographical diversities in ASR of stomach cancer in Golestan, Iran. Our results showed an increase in the number of new cases, mainly due to population size and aging. Further studies are warranted to determine the risk factors of this cancer in this high-risk population.

10-Year Trends in Dietary Intakes in the High- and Low-Risk Areas for Esophageal Cancer: A Population-Based Ecological Study in Northern Iran

BACKGROUND

We assessed dietary intakes in the high- and low-risk areas for esophageal cancer (EC) in Golestan province, Northern Iran.

METHODS

Considering the EC rates, Golestan province was divided into high- and low-risk regions. Data on households’ food consumption were obtained from the Statistical Center of Iran. We used multivariable logistic regression to assess the relationships between consumption of main food and EC risk. Adjusted odds ratios (aOR) were calculated. Joint point program was used for time trend analysis and average annual percent changes (AAPC) were reported.

RESULTS

Overall, 11910 households were recruited during 2006-2015. 4710 (39.5%) households were enrolled from the high-risk region. There were significant positive relationships between high consumption of sweets (aOR = 1.62; 95% CI: 1.24-2.10), oil/fat (aOR = 1.36; 95% CI: 1.04-1.79), and red meat (aOR = 1.33; 95% CI: 1.07-1.65) with EC risk. We found significant negative relationships between high consumption of dairy products (aOR = 0.62; 95% CI: 0.46-0.82), vegetables (aOR = 0.66; 95% CI: 0.50-0.87) and fruit (aOR = 0.72; 95% CI: 0.55-0.95) with the risk of EC. Time trend analysis showed a significant increasing trend in the proportions of households with low consumption of vegetables (AAPC = 4.71, p = 0.01) and dairy products (AAPC = 5.26, p = 0.02) in the low-risk region for EC.

CONCLUSION

Dietary intakes may be important etiological factors for EC in Northern Iran. Further studies are warranted to assess the role of dietary factors in this high-risk population.

Strontium and antimony serum levels in healthy individuals living in high- and low-risk areas of esophageal cancer

Background

It has been shown there is an upward trend for strontium (Sr) and antimony (Sb) levels from low‐risk (LR) to high‐risk (HR) areas of etiology of esophageal cancer in water, soil, and grains grown in Golestan province. In the present study, the serum levels of Sr and Sb were determined in healthy individuals living in these areas.

Methods

This cross‐sectional study was performed on fasting blood serum of adult healthy individuals collected by cluster sampling. Subjects were divided into two groups, those living in either HR or LR areas. Strontium and antimony serum levels were measured using a graphite furnace atomic absorption spectroscopy.

Results

A total of 200 volunteers were enrolled from which 96 persons (48%) and 104 persons (52%) were from either HR or LR areas, respectively. The sex distribution was 40.9% male and 59.1% female, and the average age of enrolled people was 50.9 years. The average strontium levels were 30.44 ± 4.05 and 30.29 ± 3.74 μg/L in LR and HR, respectively. It also has been shown the average antimony levels were 15.21 ± 3.40, 14.81 ± 3.17, 15.13 ± 3.62, and 15.07 ± 3.62 μg/L in LR, HR, urban, and rural populations, respectively.

Conclusion

The serum levels of strontium and antimony were not significantly different in healthy adults living in high‐ and low‐risk areas of esophageal cancer. However, the average antimony serum levels in Golestan Province were above the reference interval in different countries.

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.

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.

Opium Use and Risk of Pancreatic Cancer: A Prospective Cohort Study

Background: We examined the association between opium consumption and pancreatic cancer incidence in a large-scale prospective cohort of the general population in northeastern Iran.Methods: A total of 50,045 adults were systematically followed up (median of 7.4 years), and incident cases of pancreatic cancer were identified. Self-reported data on opium consumption was collected at baseline. Cumulative use (-year) was defined as number of nokhods (a local unit, approximately 0.2 g) of opium consumed per day multiplied by number of years consuming. Adjusted HRs and 95% confidence intervals (CIs) for the association between opium consumption and pancreatic cancer were calculated using Cox proportional hazards regression models.Results: Overall, 54 confirmed cases of pancreatic cancer were identified. Opium use of more than 81 nokhod-years (high cumulative use), compared with never use, was strongly associated with pancreatic cancer even after adjustments for multiple potential confounding factors [HR = 3.01; 95% CI, 1.25-7.26]. High cumulative consumption of opium was significantly associated with risk of pancreatic cancer after adjusting for cumulative dose of cigarette smoking [HR = 3.56; 95% CI, 1.49-8.50]. In a sensitivity analysis, we excluded participants (including 2 pancreatic cancer cases) who were recruited within the first 5 years of starting opium consumption; high cumulative use of opium was still associated with pancreatic cancer risk [HR = 2.75; 95% CI, 1.14-6.64].Conclusions: Our results showed a positive association between opium consumption and pancreatic cancer.Impact: This is the first prospective large-scale study to show the association of opium consumption with pancreatic cancer as a risk factor. Cancer Epidemiol Biomarkers Prev; 27(3); 268-73. ©2017 AACR.

Building cancer registries in a lower resource setting: The 10-year experience of Golestan, Northern Iran

INTRODUCTION

The Golestan population-based cancer registry (GPCR) was established in Golestan province, Northern Iran, within the Asian belt with predominance of upper-gastrointestinal cancers. We aimed to present the experiences of the registry in a resource-limited setting over the 10 years since its inception (2004-2013).

METHODS

The GPCR was established as a research project to enable sustainable funding. A clear plan was developed for use of the GPCR data. New primary cancers were registered based on international standards, indices of data quality were routinely assessed and age-standardized incidence rates (ASR) per 100,000 person-years calculated using IARC's CanReg-5 software.

RESULTS

Overall, 19807 new cancer cases were registered during the study period, an average of 1981 cases per annum, with overall ASR of 175.0 and 142.4 in males and females, respectively. The GPCR data suggested gastrointestinal and breast cancers as the most common malignancies in Golestan province. We observed increasing incidence rates of breast and colorectal cancers but declining trends of esophageal cancer. Overall, indices of data quality were within acceptable ranges.

CONCLUSIONS

The GPCR data have been included in IARC's Cancer Incidence in Five Continents series, were used in 21 research projects, and published as 30 research papers. The key ingredients for the successful establishment and maintenance of the GPCR included sustainable sources of funding, a clear action plan for the use of data as well as stakeholder cooperation across all areas of the registration. The GPCR may be considered as a model for planning population-based cancer registries in lesser-resourced settings.

Hazards of cigarettes, smokeless tobacco and waterpipe in a Middle Eastern Population: a Cohort Study of 50 000 individuals from Iran

BACKGROUND

There is limited information about the hazards of cigarettes, smokeless tobacco and waterpipe in the Middle East. The aim of this study was to determine the association between different types of tobacco use and earlier death in the Golestan Cohort Study.

METHODS

The Study includes 50 045 adults (aged 40-75 years) from north eastern Iran. The baseline questionnaire (2004-2008) assessed information about use of cigarettes, chewing tobacco (nass) and waterpipe. To assess the use of each type of tobacco compared with never tobacco users, we used Cox regression models adjusted for age, socioeconomic status, area of residence, education and other tobacco used, and stratified by sex, ethnicity and opium use.

RESULTS

17% of participants reported a history of cigarette smoking, 7.5% chewing tobacco (nass) and 1.1% smoking waterpipe, and these figures declined in the later birth cohorts. During a median follow-up of 8 years, 4524 deaths occurred (mean age 64.8+9.9 years). Current (HR=1.44; 95% CI 1.28 to 1.61) and former (HR=1.35; 95% CI 1.16 to 1.56) cigarette smokers had higher overall mortality relative to never tobacco users. The highest cigarette-associated risk was for cancer death among current heavy smokers (HR=2.32; 95% CI 1.66 to 3.24). Current nass chewing was associated with overall mortality (HR=1.16; 95% CI 1.01 to 1.34), and there was a 61% higher risk of cancer death in people chewing nass more than five times a day. We observed an association between the cumulative lifetime waterpipe use (waterpipe-years≥28) and both overall (HR=1.66; 95% CI 1.11 to 2.47), and cancer mortality (HR=2.82; 95% CI 1.30 to 6.11).

CONCLUSIONS

Regular use of cigarettes, smokeless tobacco and waterpipe were associated with the risk of earlier death (particularly from cancer) in our cohort.

Mortality from respiratory diseases associated with opium use: a population-based cohort study

BACKGROUND

Recent studies have suggested that opium use may increase mortality from cancer and cardiovascular diseases. However, no comprehensive study of opium use and mortality from respiratory diseases has been published. We aimed to study the association between opium use and mortality from respiratory disease using prospectively collected data.

METHODS

We used data from the Golestan Cohort Study, a prospective cohort study in northeastern Iran, with detailed, validated data on opium use and several other exposures. A total of 50 045 adults were enrolled from 2004 to 2008, and followed annually until June 2015, with a follow-up success rate of 99%. We used Cox proportional hazard regression models to evaluate the association between opium use and outcomes of interest.

RESULTS

During the follow-up period, 331 deaths from respiratory disease were reported (85 due to respiratory malignancies and 246 due to non-malignant aetiologies). Opium use was associated with an increased risk of death from any respiratory disease (adjusted HR 95% CI 3.13 (2.42 to 4.04)). The association was dose-dependent with a HR of 3.84 (2.61 to 5.67) for the highest quintile of cumulative opium use versus never use (Ptrend<0.001). The HRs (95% CI) for the associations between opium use and malignant and non-malignant causes of respiratory mortality were 1.96 (1.18 to 3.25) and 3.71 (2.76 to 4.96), respectively.

CONCLUSIONS

Long-term opium use is associated with increased mortality from both malignant and non-malignant respiratory diseases.

Reliability Analysis of a Newly Developed Questionnaire for Quality Control of Follow-up Visits in PolyIran Study

BACKGROUND

The PolyIran study is a large-scale pragmatic cluster randomized controlled trial of fixed-dose combination therapy (Polypill) for prevention of cardiovascular diseases (CVD) in Iran. The PolyIran Quality Control Program (PIQCP) including a new questionnaire was developed to assess the quality of data collection during follow-up visits. The aim of this study was to assess the inter-rater reliability of PIQCP questionnaire.

METHODS

The study was conducted in 26 (11%) randomly selected clusters (from a total of 236 PolyIran clusters). All participants within these 26 clusters were enrolled. The quality scores were measured according to the PIQCP guidelines by two independent raters. The intraclass correlation coefficients (ICC) were measured. In addition, the quality scores were categorized into good (70%) and poor (<70%). The kappa coefficient was used to assess inter-rater agreement for this categorical quality scores.

RESULTS

A total number of 945 PolyIran participants were enrolled of which, 501 (53%) were from intervention arm. In 934 participants (98.8%), the quality score could be successfully identified by both raters. The ICC (95%CI) of the overall quality scores was 0.985 (0.983-0.987). It was 0.976 (0.972-0.980) and 0.988 (0.986-0.990) in intervention and control arms, respectively. We found excellent agreement between the two raters in identifying participants with good and poor quality scores (kappa = 0.988, P < 0.001). The kappa values were 0.972 (P < 0.001) and 1.000 (P < 0.001) in intervention and control arms, respectively.

DISCUSSION

Our results suggested that the PIQCP questionnaire is a reliable tool for assessing quality of data collection in PolyIran follow-up visits. Using this measure will help us in efficient monitoring of the PolyIran follow-ups and may ensure high quality data.

Predictors of survival in oesophageal cancer patients in a high-risk area in Northern Iran: the role of health services utilisation

We aimed to determine predictors of survival in oesophageal cancer (EC) patients in a high-risk area. This study was conducted on EC patients diagnosed in 2007-2008 in Golestan province, Iran. Diagnostic (DU) and Therapeutic (TU) services utilisation indices were determined. DU and TU indices of 1 were considered as good utilisation. EC-specific survival rates were calculated. Multivariate Cox-regression model was used to calculate adjusted hazard ratios (AHRs). Two hundred and twenty-three EC subjects were enrolled. The median survival time was 10.47 months and the 5-year survival rate was 11%. Cox-regression analysis suggested that stage of tumour (AHR_regional  = 3.75, 95% confidence interval [CI]: 2.34-6.00; AHR_metastasis  = 12.21, 95% CI: 7.42-20.08) and TU (AHR = 1.78, 95% CI: 1.25-2.52) were the strongest variables related to EC survival. The median survival time in patients with good and poor TU were 14.37 and 8.53 months respectively (p < .01). There was no significant relationship between DU and EC survival. We found relatively low survival rates in our EC patients when compared with developed countries. Our results also suggested an increasing trend for EC survival rate during recent years. Good TU could predict higher survival rates. Patients' access to therapeutic services may be considered as an important indicator in decision-making for controlling EC.

Diagnostic values of serum levels of pepsinogens and gastrin-17 for screening gastritis and gastric cancer in a high risk area in northern Iran

BACKGROUND

Gastric cancer (GC) is the second cause of cancer related death in the world. It may develop by progression from its precancerous condition, called gastric atrophy (GA) due to gastritis. The aim of this study was to evaluate the accuracy of serum levels of pepsinogens (Pg) and gastrin-17 (G17) as non-invasive methods to discriminate GA or GC (GA/GC) patients.

MATERIALS AND METHODS

Subjects referred to gastrointestinal clinics of Golestan province of Iran during 2010 and 2011 were invited to participate. Serum levels of PgI, PgII and G17 were measured using a GastroPanel kit. Based on the pathological examination of endoscopic biopsy samples, subjects were classified into four groups: normal, non-atrophic gastritis, GA, and GC. Receiver operating curve (ROC) analysis was used to determine cut-off values. Indices of validity were calculated for serum markers.

RESULTS

Study groups were normal individuals (n=74), non-atrophic gastritis (n=90), GA (n=31) and GC patients (n=30). The best cut-off points for PgI, PgI/II ratio, G17 and HP were 80 μg/L, 10, 6 pmol/L, and 20 EIU, respectively. PgI could differentiate GA/GC with high accuracy (AUC=0.83; 95%CI: 0.76-0.89). The accuracy of a combination of PgI and PgI/II ratio for detecting GA/GC was also relatively high (AUC=0.78; 95%CI: 0.70-0.86).

CONCLUSIONS

Our findings suggested PgI alone as well as a combination of PgI and PgI/II ratio are valid markers to differentiate GA/GC. Therefore, Pgs may be considered in conducting GC screening programs in high-risk areas.

Temporal variations of dietary habits in a high-risk area for upper gastrointestinal cancers: a population-based study from northern Iran

BACKGROUND

Nutrition transition is a global health problem, especially in developing countries. It is known as an important factor for development of different types of health conditions including cancers.

OBJECTIVES

We aimed to assess the pattern of nutrition transition in a high-risk area for upper gastrointestinal cancers in Northern Iran during the last decade.

MATERIALS AND METHODS

This cross-sectional study was conducted on households of Golestan province, Iran. Data on household food consumption between 2001 and 2010 were obtained from the Statistical Center of Iran. The proportions of households with medium/high consumption of main foods were calculated for each year. Joint point software was used for assessing trends. Annual percent changes (APCs) and 95%CIs were calculated.

RESULTS

In total, 12,060 households were recruited. The APCs (95%CI) of the proportion of households medium/high consumption of cereals, vegetables, legumes, fish, dairy products and meats were -3.1 (-4.1 to -2.2), -2.9 (-3.8 to -2.1), -2.3 (-3.2 to -1.4), -2.8 (-3.3 to -2.4), -1.9 (-3.0 to -0.9) and 2.7 (1.2 to 4.3), respectively.

CONCLUSIONS

We found significant increase in meat consumption among our population between 2001 and 2010. Our results also suggested significant decreasing trend in consumption of so-called healthy foods including, plant foods, fish, and dairy products. Regarding its correlation with health conditions including cancers, nutrition transition should be considered as a priority in health policy making in our region as well as other high-risk populations. It is recommended to conduct community level interventions to increase consumption of plant foods, fish, and dairy products.

Endoscopic screening for precancerous lesions of the esophagus in a high risk area in Northern Iran

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is a major health problem in many developing countries including Iran. ESCC has a very poor prognosis, largely due to late diagnosis. As a first step in developing an early detection and treatment program, we conducted a population-based endoscopic screening for ESCC and its precursor lesion, esophageal squamous dysplasia (ESD) in asymptomatic adults from Golestan Province, northern Iran, a high-risk area for ESCC, to evaluate the feasibility of such a program and to document the prevalence and risk factor correlates of ESD.

METHODS

This cross-sectional study was conducted among participants of the Golestan Cohort Study (GCS), a population-based cohort of 50,000 adults in eastern Golestan Province. Randomly selected GCS participants were invited by telephone. Those who accepted were referred to a central endoscopy clinic. Eligible subjects were consented and then asked to fill in a brief questionnaire. Detailed information about selected risk factors was obtained from the GCS main database. Endoscopic examination with Lugol's iodine staining was performed, biopsies were taken from unstained lesions as well as the normally stained mucosa of the esophagus, and the biopsies were diagnosed by expert pathologists according to previously described criteria.

RESULTS

In total, 1906 GCS subjects were invited, of whom only 302 subjects (15.8%) were successfully enrolled. Esophagitis (29.5%) and ESD (6.0%) were the most common pathological diagnoses. Turkmen ethnicity (adjusted OR = 8.61; 95%CI: 2.48-29.83), being older than the median age (OR = 7.7; 95% CI: 1.99-29.87), and using deep frying cooking methods (OR = 4.65; 95%CI: 1.19-18.22) were the strongest predictors for ESD. There were significant relationships between esophagitis and smoking (p-value<0.001), drinking hot tea (P value = 0.02) and lack of education (P value = 0.004).

CONCLUSION

We observed a low rate for participation in endoscopic screening. Overall prevalence of ESD was 6.0%. Developing non-endoscopic primary screening methods and screening individuals with one or more risk factors may improve these rates.

Two novel splice variants of SOX2OT, SOX2OT-S1, and SOX2OT-S2 are coupregulated with SOX2 and OCT4 in esophageal squamous cell carcinoma

Long noncoding RNAs (lncRNAs) have emerged as new regulators of stem cell pluripotency and tumorigenesis. The SOX2 gene, a master regulator of pluripotency, is embedded within the third intron of a lncRNA known as SOX2 overlapping transcript (SOX2OT). SOX2OT has been suspected to participate in regulation of SOX2 expression and/or other related processes; nevertheless, its potential involvement in tumor initiation and/or progression is unclear. Here, we have evaluated a possible correlation between expression patterns of SOX2OT and those of master regulators of pluripotency, SOX2 and OCT4, in esophageal squamous cell carcinoma (ESCC) tissue samples. We have also examined its potential function in the human embryonic carcinoma stem cell line, NTERA2 (NT2), which highly expresses SOX2OT, SOX2, and OCT4. Our data revealed a significant coupregulation of SOX2OT along with SOX2 and OCT4 in tumor samples, compared to the non-tumor tissues obtained from the margin of same tumors. We also identified two novel splice variants of SOX2OT (SOX2OT-S1 and SOX2OT-S2) which coupregulated with SOX2 and OCT4 in ESCCs. Suppressing SOX2OT variants caused a profound alteration in cell cycle distribution, including a 5.9 and 6.9 time increase in sub-G1 phase of cell cycle for SOX2OT-S1 and SOX2OT-S2, respectively. The expression of all variants was significantly diminished, upon the induction of neural differentiation in NT2 cells, suggesting their potential functional links to the undifferentiated state of the cells. Our data suggest a part for SOX2OT spliced variants in tumor initiation and/or progression as well as regulating pluripotent state of stem cells.

Pilot study of cytological testing for oesophageal squamous cell dysplasia in a high-risk area in Northern Iran

Background:

Oesophageal squamous cell carcinoma (ESCC) is a fatal disease with 5-year survival rates of <5% in Northern Iran. Oesophageal squamous dysplasia (ESD) is the precursor histologic lesion of ESCC. This pilot study was conducted to assess the feasibility, safety, and acceptability of non-endoscopic cytological examination of the oesophagus and to provide initial data on the accuracy of cytological atypia for identifying patients with ESD in this very-high-risk area.

Methods:

Randomly selected asymptomatic participants of the Golestan Cohort Study were recruited. A cytological specimen was taken using a capsule sponge device and evaluated for atypical cells. Sections of the cytological specimen were also stained for p53 protein. Patient acceptability was assessed using a visual analogue scale. The cytological diagnosis was compared with a chromoendoscopic examination using Lugol's solution.

Results:

Three hundred and forty-four subjects (43% male, mean (s.d.) age 55.6 (7.9) years) were referred to the study clinic. Three hundred and twelve met eligibility criteria and consented, of which 301 subjects (96.5%) completed both cytological and endoscopic examinations. There were no complications. Most of the participants (279; 92.7%) were satisfied with the examination. The sensitivity and specificity of the cytological examination for identifying subjects with high-grade ESD were 100 and 97%, respectively. We found an accuracy of 100% (95% CI=99–100%) for a combination of cytological examination and p53 staining to detect high-grade ESD.

Conclusions:

The capsule sponge methodology seems to be a feasible, safe, and acceptable method for diagnosing precancerous lesions of the oesophagus in this population, with promising initial accuracy data for the detection of high-grade ESD.

Selenium levels in rice samples from high and low risk areas for esophageal cancer

OBJECTIVE

To assess the relationship between selenium (Se) concentration in rice and the incidence of esophageal cancer (EC) in a high risk area in Northern Iran.

METHODS

This ecological study was conducted in Golestan province of Iran in 2012. In this area, 45714 acres of land are cultivated by rice. A total of 69 rice samples were taken. We investigated Se concentrations by the voltammetric method. Statistical analysis was performed using the Pearson correlation test and Mann-Whitney U test.

RESULTS

The mean (+/-SD) Se level in rice samples was 0.229 (+/-0.145) mg/kg. The Se concentration was significantly higher in rice samples from high EC rate areas (0.35 mg/kg) compared with low risk areas (0.16 mg/kg) (p<0.001). There was a significant positive correlation between the levels of Se in rice and the incidence rate of EC (p=0.03).

CONCLUSION

We found a high rice Se concentration and a significant positive relationship between rice Se levels and EC rates in the Golestan province of Iran. High soil and rice Se levels may play a possible role in the pathogenesis of EC in this area.

Endoscopic screening for esophageal squamous cell carcinoma

Esophageal cancer (EC) is the eighth common cancer and the sixth most common cause of death from cancer worldwide. Esophageal squamous cell carcinoma (ESCC) remains the most common type of EC in the developing world and an important health problem in high-risk areas. Most of ESCC cases present in late stages, resulting in delayed diagnosis and poor prognosis. Prevention is the most effective strategy to control ESCC. Primary and secondary preventive methods may be considered for ESCC. In primary prevention, we try to avoid known risk factors. The aim of the secondary preventive method (ESCC screening programs) is to detect and eliminate premalignant precursor lesion of ESCC, preventing its progression into advanced stages. Similar to all population-based screening programs, any screening for early detection of ESCC must be cost-effective; otherwise, screening may not be indicated in that population. Endoscopy with iodine staining has been accepted as a population-level ESCC screening program in some high-risk areas including parts of China. This method may be too expensive and invasive in other high-risk communities. Nonendoscopic methods may be more applicable in these populations for population-based screenings. The limitations (questionable validity and costs) of new endoscopic imaging modalities, including narrow-band imaging (NBI), made them inappropriate to be used in population-level ESCC screening programs. Low-cost, less-invasive endoscopic imaging methods with acceptable diagnostic performance may make screening of ESCC in high-risk areas cost-effective.

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.

Gastroesophageal Reflux Disease and overall and Cause-specific Mortality: A Prospective Study of 50000 Individuals

BACKGROUND Only a few studies in Western countries have investigated the association between gastroesophageal reflux disease (GERD) and mortality at the general population level and they have shown mixed results. This study investigated the association between GERD symptoms and overall and cause-specific mortality in a large prospective population-based study in Golestan Province, Iran. METHODS Baseline data on frequency, onset time, and patient-perceived severity of GERD symptoms were available for 50001 participants in the Golestan Cohort Study (GCS). We identified 3107 deaths (including 1146 circulatory and 470 cancer-related) with an average follow-up of 6.4 years and calculated hazard ratios (HR) and 95% confidence intervals (CI) adjusted for multiple potential confounders. RESULTS Severe daily symptoms (defined as symptoms interfering with daily work or causing nighttime awakenings on a daily bases, reported by 4.3% of participants) were associated with cancer mortality (HR 1.48, 95% CI: 1.04-2.05). This increase was too small to noticeably affect overall mortality. Mortality was not associated with onset time or frequency of GERD and was not increased with mild to moderate symptoms. CONCLUSION We have observed an association with GERD and increased cancer mortality in a small group of individuals that had severe symptoms. Most patients with mild to moderate GERD can be re-assured that their symptoms are not associated with increased mortality.

Determinants of gastroesophageal reflux disease, including hookah smoking and opium use- a cross-sectional analysis of 50,000 individuals

BACKGROUND

Gastroesophageal reflux disease (GERD) is a common cause of discomfort and morbidity worldwide. However, information on determinants of GERD from large-scale studies in low- to medium-income countries is limited. We investigated the factors associated with different measures of GERD symptoms, including frequency, patient-perceived severity, and onset time.

METHODS

We performed a cross-sectional analysis of the baseline data from a population-based cohort study of ∼ 50,000 individuals in in Golestan Province, Iran. GERD symptoms in this study included regurgitation and/or heartburn.

RESULTS

Approximately 20% of participants reported at least weekly symptoms. Daily symptoms were less commonly reported by men, those of Turkmen ethnicity, and nass chewers. On the other hand, age, body mass index, alcohol drinking, cigarette smoking, opium use, lower socioeconomic status, and lower physical activity were associated with daily symptoms. Most of these factors showed similar associations with severe symptoms. Women with higher BMI and waist to hip ratio were more likely to report frequent and severe GERD symptoms. Hookah smoking (OR 1.34, 95% CI 1.02-1.75) and opium use (OR 1.70, 95% CI 1.55-1.87) were associated with severe symptoms, whereas nass chewing had an inverse association (OR 0.87, 95% CI 0.76-0.99). After exclusion of cigarette smokers, hookah smoking was still positively associated and nass chewing was inversely associated with GERD symptoms (all frequencies combined).

CONCLUSION

GERD is common in this population. The associations of hookah and opium use and inverse association of nass use with GERD symptoms are reported for the first time. Further studies are required to investigate the nature of these associations. Other determinants of GERD were mostly comparable to those reported elsewhere.

A U-shaped relationship between haematocrit and mortality in a large prospective cohort study

BACKGROUND

Only a limited number of studies have investigated the correlation between haematocrit (HCT) and mortality in the general population, and few of those studies have had data on a wide range of low and high levels of HCT. We investigated the association between baseline HCT and mortality in a prospective cohort study of 49,983 adult subjects in Iran with a broad spectrum of HCT values.

METHODS

Data on socio-demographic and life-style factors, past medical history, and levels of HCT were collected at enrollment. During a mean follow-up of 5 years (follow-up success rate ~99%), 2262 deaths were reported. Cox proportional hazards regression models were used to estimate hazard ratios and corresponding 95% confidence intervals.

RESULTS

There was a U-shaped relationship between categories of HCT and mortality in both sexes: both low and high levels of HCT were associated with increased overall mortality and mortality from cardiovascular disease. The U-shaped relationship persisted after several sensitivity analyses were done, including analyses restricted to non-smokers and non-users of opium; analyses excluding deaths from accidents and other external causes as well as deaths of persons with self-reported ischemic heart disease at the baseline interview for the study; and analyses excluding the first 2 years of follow-up. Self-reported past medical history and lack of data about lipids and other cellular blood components were the major limitations of the study.

CONCLUSIONS

Low and high levels of HCT are associated with increased mortality in the general population. The findings in the present study can be of particular importance for low- and middle-income countries in which a substantial proportion of the population lives with suboptimal levels of HCT.

Epidemiology of leukemia and multiple myeloma in Golestan, Iran

BACKGROUND

The aim of this paper was to present the incidence rates of leukemia and multiple myeloma (MM) in Golestan province located in northeastern Iran during 2004-2009.

MATERIALS AND METHODS

This was a descriptive cross-sectional study. Data on newly diagnosed (incident) leukemia and MM cases were obtained from collected from Golestan population-based cancer registry. Data was entered into CanReg-4 software. Age standardized incidence rates (ASR) (per 100000 person-years) for leukemia and MM were calculated. Data on Golestan population was obtained from the data of Iranian national census in 2006.

RESULTS

Totally, 11036 new cancer cases were registered in GPRC from 2004-2009. Leukemia and MM accounted for 693 and 124 of cases, respectively. The mean age in patients with leukemia and MM was 43.8 and 62.4 years, respectively. The ASRs for leukemia among men and women were 10.4 and 7.8, respectively (p<0.001). The ASRs for MM were 2.1 and 2 in men and women, respectively (p=0.93). The rate of leukemia was significantly higher in rural areas (p=0.02) whereas the incidence of MM was higher in urban areas (p<0.001).

CONCLUSIONS

Our results showed a high incidence rate of leukemia in Golestan province of Iran. The incidence of leukemia was significantly higher in males and residents of rural areas. High exposure to pesticides and other agricultural related products may be a possible explanation for epidemiological pattern of leukemia in this area. Determining and controlling important risk factors, especially environmental factors, of leukemia may lead to decrease in its burden in Golestan province of Iran.

Goiter frequency is more strongly associated with gastric adenocarcinoma than urine iodine level

PURPOSE

We designed our study to evaluate the hypothesis that gastric cancer is correlated with iodine deficiency or thyroid dysfunction.

MATERIALS AND METHODS

We investigated the total body iodine reserve, thyroid function status and autoimmune disorder in 40 recently diagnosed gastric adenocarcinoma cases versus 80 healthy controls. The participants came from a region with high gastric cancer rate but sufficient iodine supply due to salt iodination. The investigation included urine iodine level, thyroid gland clinical and ultrasonographic examination, and thyroid function tests.

RESULTS

Goiter was detected more frequently in the case group (P=0.001); such a finding, however, was not true for lower than normal urine iodine levels. The free T3 mean level was significantly lower in the case group compared to the control group (P=0.005).

CONCLUSIONS

The higher prevalence of goiter rather than low levels of urinary iodine in gastric adenocarcinoma cases suggests that goiter, perhaps due to protracted but currently adjusted iodine deficiency, is more likely to be associated with gastric adenocarcinoma compared to the existing iodine deficiency itself.

Predictors of Colorectal Cancer Survival in Golestan, Iran: A Population-based Study

OBJECTIVES

We aimed to investigate factors associated with colorectal cancer survival in Golestan, Iran.

METHODS

We used a population based cancer registry to recruit study subjects. All patients registered since 2004 were contacted and data were collected using structured questionnaires and trained interviewers. All the existing evidences to determine the stage of the cancer were also collected. The time from first diagnosis to death was compared in patients according to their stage of cancer using the Kaplan-Meir method. A Cox proportional hazard model was built to examine their survival experience by taking into account other covariates.

RESULTS

Out of a total of 345 subjects, 227 were traced. Median age of the subjects was 54 and more than 42% were under 50 years old. We found 132 deaths among these patients, 5 of which were non-colorectal related deaths. The median survival time for the entire cohort was 3.56 years. A borderline significant difference in survival experience was detected for ethnicity (log rank test, p=0.053). Using Cox proportional hazard modeling, only cancer stage remained significantly associated with time of death in the final model.

CONCLUSIONS

Colorectal cancer occurs at a younger age among people living in Golestan province. A very young age at presentation and what appears to be a high proportion of patients presenting with late stage in this area suggest this population might benefit substantially from early diagnoses by introducing age adapted screening programs.

Aflatoxin contamination of wheat flour and the risk of esophageal cancer in a high risk area in Iran

BACKGROUND

Golestan province in northeastern Iran has been known as a high-risk area for esophageal cancer (EC). This study was conducted to assess aflatoxin (AF) contamination of wheat flour (WF) samples in high and low EC-risk areas of Golestan province.

METHODS

Four WF samples were collected randomly from each of 25 active silos throughout the province in 2009. The levels of AFs were measured using the High-performance liquid chromatography method. Using the data of EC rates obtained from Golestan population-based cancer registry, the province was divided into high and low risk areas for EC. Student t-test and multivariate regression analysis were used to compare the levels of aflatoxins as well as the condition of silos between the two areas.

RESULTS

One hundred WF samples were collected. The mean levels of total aflatoxin and aflatoxin B1 was 1.99 and 0.53 ng g(-1), respectively. The levels of total AF (p = 0.03), AFG2 (p = 0.02) and AFB1 (p = 0.003) were significantly higher in samples obtained from high risk area. Multivariate regression analysis showed that humidity of silo was the most important source of difference between silos of the two areas (p = 0.04).

CONCLUSION

We found a positive relationship between AF level of WF samples and the risk of EC. So, AF contamination may be a possible risk factor for EC in our region. We also found that humidity of silos was the most important determinant of AF contamination of WF. Intensive control of silos conditions including humidity and temperature are needed especially in high EC-risk areas.

Polycyclic aromatic hydrocarbons and esophageal squamous cell carcinoma

Esophageal cancer (EC) is the 8th most common cancer and the 6th most frequent cause of cancer mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common type of EC. Exposure to polycyclic aromatic hydrocarbons (PAHs) has been suggested as a risk factor for developing ESCC. In this paper we will review different aspects of the relationship between PAH exposure and ESCC. PAHs are a group of compounds that are formed by incomplete combustion of organic matter. Studies in humans have shown an association between PAH exposure and development of ESCC in many populations. The results of a recent case-control study in a high risk population in northeastern Iran showed a dramatic dose-response relationship between PAH content in non-tumor esophageal tissue (the target tissue for esophageal carcinogenesis) and ESCC case status, consistent with a causal role for PAH exposure in the pathogenesis of ESCC.  Identifying the main sources of exposure to PAHs may be the first and most important step in designing appropriate PAH-reduction interventions for controlling ESCC, especially in high risk areas. Coal smoke and drinking mate have been suggested as important modifiable sources of PAH exposure in China and Brazil, respectively. But the primary source of exposure to PAHs in other high risk areas for ESCC, such as northeastern Iran, has not yet been identified. Thus, environmental studies to determining important sources of PAH exposure should be considered as a high priority in future research projects in these areas.

The gastro-esophageal malignancies in Northern Iran research project: impact on the health research and health care systems in Iran

BACKGROUND

The Gastro-Esophageal Malignancies in Northern Iran (GEMINI) research project is an example of recent progress in health research in Iran. The original aim of this project was to identify etiologic factors and prevention measures for upper gastrointestinal cancers in Northern provinces of Iran, but its achievements have gone much beyond this initial goal.

METHODS

GEMINI consists of several projects including cancer registries, pilot studies, case-control studies, and the Golestan Cohort Study. GEMINI has been conducted through extensive collaborations between the Digestive Disease Research Center of Tehran University of Medical Sciences with other domestic and international health organizations. The achievements of GEMINI include producing new knowledge, introducing new research methods, developing and expanding health research and health care infrastructures, investing in human resources, and increasing the awareness and knowledge of policy makers and officials at all levels about the importance of chronic diseases in Iran's health priorities.

CONCLUSION

The success of GEMINI reveals the feasibility of large-scale health research studies in developing countries and serves as a successful model not only for health research in Iran, but also for similar research studies in other developing nations.

Comparison of three with six regions of interest analyses in patients with idiopathic constipation undertaking colon transit scintigraphy using 67Ga-citrate

OBJECTIVE AND INTRODUCTION: Preparation of data from 6 geometric regions of interest in the colon is time consuming, and can become impractical in the environment of busy Nuclear Medicine Departments. Therefore, we have investigated and demonstrated an alternative method for obtaining the same diagnostic information from an analysis of patients with idiopathic constipation who underwent colon transit scintigraphy using 67Ga-citrate. Data analysis methods using three regions of interest are compared to the results obtained using the more time consuming 6 regions of interest method to analyze the data.

MATERIALS AND METHODS

In this study, we report our results of the comparative reanalysis of data obtained by more traditional methods. We compare 3 regions of interest (ROI) which were taken from areas including the right colon, left colon and the rectosigmoid colon, with original work using our alternative 6 (ROI) diagnostic methodology. In addition, the proximal colonic emptying (PCE) was determined at 24 hr post ingestion among members of 3 identified subject groups.

RESULTS

The distribution of activity as the ingested 67Ga-citrate passes through the colon constitutes an activity profile. The mean activity position in the colon can be determined from subsequent radiographic images and from this the mean clearance time can be calculated.  In quantitative assessment, this represents the time at which half of activity was eliminated from colon (mean half clearance time - MCT) which did not appear different in the reanalysis. There is no significant difference in the current study in GMC 24h, GMC 48h and GMC 72h between two groups using the Man Whitney u test (p > 0.05), while in the previous work the results were statistically significant for the two later time periods GMC (GMC 48h and GMC 72h) (p = 0.016 and p = 0.027 respectively). The PCE in the group 1 was = 2.50 (0.37); group 2, 1.57 (0.47) and group 3, 2.97. The PCE was not different between the two groups (p = 0.21).

CONCLUSIONS

This investigation demonstrated that the radionuclide colon transit study using 67Ga-citrate is a safe, physiologic, and quantitative method for evaluating the transit of fecal material from cecum to rectum. Although, the visual assessment of diagnosis of the subjects in the two analyses is the same, it was not completely supported by quantitative measurements. Therefore, further studies need to be done.

Complete improvement in a patient with multiple irreversible defects of the left ventricle on 99m technetium-sestamibi SPECT after percutaneous coronary intervention

99mTc-sestamibi has been investigated as a potential viability marker; initial studies have shown good concordance between 201Tl and 99mTc-sestamibi activities in both viable and nonviable myocardium. However, assessment of myocardial viability by 99mTc-sestamibi remains controversial for tissue recovery after revascularization. Here, we present a patient with several regions of severely diminished and irreversible (defect persisting in both early and delay images of each set scanning) defects on initial scan which were dissolved completely on the follow up scan after an intervention. In a 75 year-old Asian woman with acute myocardial infarction who received thrombolytic therapy and subjected to percutaneous coronary angiography (PCI) on day 28 after acute myocardial infarction(MI), resting 99mTc-sestamibi SPECT was applied on day 4 (initial scan) and 138 (follow up scan) after acute MI at 30 and 180 min after injection of tracer (740 MBq); Two-dimensional echocardiography was carried out at the same time. On the initial image set, there was irreversible defects in the apex, anteroapical, inferoapical, anteroseptal, septal and also anterior walls, while the follow up image was normal in all regions.The angiography intervention showed just significant stenosis on left anterior descending (LAD) vessel (95%). This may highlight the failure of 99mTc-sestamibi as a marker of myocardial viability and also mandate further validating of the procedure with follow up scan or other modalities for myocardial viability investigation.

Cancer incidence in Golestan Province: report of an ongoing population-based cancer registry in Iran between 2004 and 2008

BACKGROUND

Golestan Province, at the western end of the Asian esophageal cancer (EC) belt in northeastern Iran, was reported to have one of the highest worldwide rates of EC in the 1970s. We have previously shown a declining incidence of EC in Golestan during the last decades. This study reports additional new results from the Golestan Population-based Cancer Registry (GPCR).

METHODS

The GPCR collected data from newly diagnosed (incident) cancer cases from all 68 public and private diagnostic and therapeutic centers in Golestan Province. CanReg-4 software was used for data entry and analysis based on the guidelines of the International Agency for Research on Cancer (IARC). Age-standardized incidence rates (ASR) of cancers were calculated using the 2000 world standard population.

RESULTS

From 2004 through 2008, 9007 new cancer cases were reported to the GPCR. The mean (SD) age was 55.5 (18.6) years, and 54% were diagnosed in men. The ASRs of all cancers were 175.3 and 141.1 per 100,000 person-years for males and females, respectively. Cancers of the stomach (ASR:30.7), esophagus (24.3), and lung (15.4) were the most common cancers in males. In females, breast cancer (ASR:26.9) was followed by malignancies of the esophagus (19.1) and stomach (12.4). The diagnosis of cancer was based on histopathological reports in 71% and on death certificate only in 9% of cases.

CONCLUSIONS

The EC incidence rate continues to decline in Golestan, while the incidence rates of stomach, colorectal, and breast cancers continue to increase.

Opium use and mortality in Golestan Cohort Study: prospective cohort study of 50,000 adults in Iran

OBJECTIVES

To investigate the association between opium use and subsequent risk of death.

DESIGN

Prospective cohort study.

SETTING

The Golestan Cohort Study in north-eastern Iran collected detailed validated data on opium use and other exposures at baseline. Participants were enrolled between January 2004 and June 2008 and were followed to May 2011, with a follow-up success rate of over 99%.

PARTICIPANTS

50,045 participants aged 40-75 at baseline.

MAIN OUTCOMES

Mortality, all cause and major subcategories.

RESULTS

17% (n = 8487) of the participants reported opium use, with a mean duration of 12.7 years. During the follow-up period 2145 deaths were reported. The adjusted hazard ratio for all cause mortality associated with ever use of opium was 1.86 (95% confidence interval 1.68 to 2.06). Opium consumption was significantly associated with increased risks of deaths from several causes including circulatory diseases (hazard ratio 1.81) and cancer (1.61). The strongest associations were seen with deaths from asthma, tuberculosis, and chronic obstructive pulmonary disease (11.0, 6.22, and 5.44, respectively). After exclusion of people who self prescribed opium after the onset of major chronic illnesses, the associations remained strong with a dose-response relation.

CONCLUSION

Opium users have an increased risk of death from multiple causes compared with non-users. Increased risks were also seen in people who used low amounts of opium for a long period and those who had no major illness before use.

None-endoscopic Screening for Esophageal Squamous Cell Carcinoma- A Review

Esophageal cancer (EC) is the eighth most common cancer and sixth most frequent cause of cancer mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common type of EC. ESCC develops by progression from premalignant lesions, which are called esophageal squamous dysplasia (ESD). Prevention is the most effective strategy for controlling this disease. Generally, two methods may be defined for ESCC prevention. The aim of the first preventive method is to prevent the initiation of ESD by avoiding the known risk factors, or primary prevention. Secondary prevention focuses on detection of the disease in its early curable stage, thus preventing its progression into advanced stages. Endoscopy with iodine staining and biopsy is the diagnostic choice for ESD. However it is invasive and expensive, and not accepted by asymptomatic ESD cases. Therefore, it is necessary to find a non-endoscopic screening method. Despite the large number of studies conducted worldwide, no approved method has been developed for ESCC screening. Regarding the multi-factorial nature of ESCC, it is proposed that the use of a combination of various criteria, such as cytological examination, risk factors, genetic alteration, and molecular markers may result in the development of a comprehensive and effective ESCC screening program.

The association of rate pressure product (RPP) and myocardial perfusion imaging (MPI) findings: a preliminary study

Introduction: The product of heart rate and systolic blood pressure, termed as rate-pressure product (RPP), is a very reliable indicator of myocardial oxygen demand and is widely used clinically. There have been previous attempts to describe the relationship between RPP and the onset of pain in angina pectoris. The current study aimed to evaluate the association between RPP results and scan findings.

Materials and methods: In total, 497 patients with suspected coronary artery disease (CAD) underwent gated, single-photon emission computed tomography (SPECT) imaging with dipyridamole, exercise, or dobutamine stress, and were included in this study. Baseline and maximum heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and electrocardiogram (ECG) results were recorded. The rate-pressure product (RPP) was calculated as the product of heart rate and systolic arterial pressure for both baseline and maximum measures. The difference between the RPP max and the basal RPP is known as the RPP reserve. Researchers also obtained semi-quantitative analyses of myocardial perfusion imaging (MPI), using gated software, demographic information, risk factors of CAD, and pretest likelihoods of CAD using nomograms.

Result: Four hundred and ninety-seven cases, including 426 patients with dipyridamole stress, 59 with exercise stress, and 12 with dobutamine stress, underwent myocardial perfusion imaging. Scan results were positive in 194 (45.5%) and negative in 232 (54.5%) patients with dipyridamole stress. In patients with exercise stress, the scan was positive in 24 (40.7%) cases and negative in 35 (59.3%) cases. In dobutamine stressed patients, the scan was positive in 6 (50%) cases and negative in the 6 remaining cases. Dipyridamole stress resulted in a significant difference between HR at rest and at maximum (28.95 ± 24.53, p-value<0.0001), between systolic BP at rest and maximum (6.75 ± 12.50, p-value<0.0001) and between diastolic BP at rest and maximum (1.45 ± 5.80; p-value<0.0001). There was a significant correlation between sum stress scores (SSS) and reserved RPP (r= −0.12, p-value<0.001) which, in dipyridamole patients, was r=−0.18, p-value=0.0001). In addition, there was a significant association between reserved RPP and risk of CAD (p-value<0.001). In the patients with dipyridamole stress, the ejection fraction (EF) change (odds ratio =0.92; 95% CI: 0.86-0.98; p=0.01), reserve RPP (odds ratio =1.00; 95% CI: 1.00-1.00; p=0.04), risk of CAD (odds ratio =5.80; 95% CI: 3.21-10.50; p<0.0001) and age (odds ratio =0.94; 95% CI: 0.89-0.98; p=0.01) were associated significantly with MPI results, using multiple logistic regressions.

Conclusion. The study demonstrated that RPP is associated with MPI findings using gated SPECT imaging with dipyridamole stress. However, to confirm this preliminary result, further studies are mandatory.