Esophageal cancer in northern Iran: From the seventies up to now Mitra Saadatian-Elahi

Damavand, the highest mountain in Iran (5671 m)

Zoroastrian's tower

Tea plantation

Incidence of esophageal cancer worldwide <1.9 <3.2<5.9 <10.0 <38.7 Men all ages

Esophageal cancer in northern Iran: historic Avicenna: referred to cancer of the esophagus Kmet :1965 large changes in the occurrence of esophageal cancer over a relatively small area in northern Iran Institute of Public Health of Tehran and IARC: Estabilishment of cancer registry

Incidence of esophageal cancer in Northern Iran Mahboubi et al, Br. J. Cancer 1973

Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (1) Ecological studies Comparison of demographic and lifestyle habits between 3800 subjects in 38 randomly selected villages 5-days dietary survey in 6 households in each village Analysis of main foodstuffs for nitrosamines, PAH, aflatoxin, nitrate and nitrite Joint Iran-IARC study group, J.Natl. Cancer. Inst; 1977

Overall Very low alcohol consumption No evidence of high levels of chemical agents Highest vs lowest incidence area High frequency of opium and nass consumption High frequency of hot tea consumption Lack of fresh fruits and vegetables intake Low consumption of animal protein including fish Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (2)

Case-control studies: 344 cases and 688 controls matched for age (± 5years), residential area and ethnicity Information on demographic, socio-economic status, dietary habits, cooking and heating methods Cook-Mozaffari et al, Br. J.of Cancer, 1979 Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (3)

Results: Cases compared to controls had Lower intake of fresh fruits and vegetables Lower socio-economic status Higher cigarette consumption Higher temperature of drinking tea Cook-Mozaffari et al, Br. J.of Cancer, 1979 Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (4)

Opium use Measurement of morphine metabolites in urine of households with a case of esophageal cancer and control households Urine sample positive if morphine higher than 0.3  g/ml Prevalence of appreciable levels (  1  g/ml) higher in high incidence area and in members of case households Opium use is involved in the etiology of esophageal cancer in northern Iran Ghadirian et al. Int J. Cancer, 1985 Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (5)

Conclusions: High risk for esophageal cancer in northeast Iran might be explained by severely restricted diet in conjunction with thermal injury and exposure to a carcinogenic agent derived from opium. A genetic component can not be excluded because the highest incidence population are all of Turkmen origin Early studies of environmental etiologies of esophageal cancer in Golestan province of Iran (6)

4192 asymptomatic adults above 30 years Oesophageal baloon cytology screening Endoscopic examination Age-standardized rates for ESCC per : for men and for women High frequency of ESCC reported earlier is confirmed F Saidi, British journal of cancer, 2000 Re-evaluation of the incidence of esophageal cancer

On going studies

Collaborative studies between IARC, NCI and the Digestive Disease Research Center (DDRC) - Case-control study (300 cases/300 controls) - Cohort study involving subjects - Feasibility study = pilot phase Ongoing epidemiological studies of esophageal cancer in Golestan province of Iran

To evaluate logistical aspects of the project, response rate and to measure prevalence of exposure To assess the reliability of interview by conducting repeated interviews on a sample of subjects To compare the FFQ with a reference method based on 24h recall as well as biomarkers of diet To compare data from questionnaire on opium consumption with biological markers measured in urine To assess reliability of measuring tea temperature Pilot study: Objectives

Subjects: 645 subjects from Gonbad and 682 from 3 rural villages aged between 35 and 75 years old Interview: 1) Main questionnaire: demographic and socio- economic status, past and present medical history, family history of cancer, nass and opium use and GI symptoms 2) FFQ including 150 items 3) Tea temperature measurement Pilot study: Design (1)

Biological samples: hair, nail, blood and urine Repeated interview: 150 subjects 2 months apart from the first interview Dietary survey: 130 subjects during 1 year period Pilot study: Design (2)

Evaluation of logistical aspects and measurement of exposure

Main characteristics of the study subjects VariableMalesFemales Age52.2 (±12.4)50.5 (± 11.2) Place of residence Urban177 (39.6%)261 (42.8%) Rural270 (60.4%)349 (57.2%) Ethnicity Turkmen286 (63.9%)378 (61.9%) Fars120 (26.8%)168 (27.5%) Others40 (9.2%)68 (10.5%) Response rate:68% in Urban area 91% in Rural area

Selected characteristics of subjects enrolled in the pilot study, by gender and urban/rural residence ExposureUrban men N=177 Urban women N=261 Rural men N=270 Rural women N=349 Illiterate28 (16.2%)87 (34%)152 (57%)312 (91%)) Alcohol31 (17.5%)0 (0.0)9 (3.3%)0 (0.0) Tobacco: recent 42 (23.7%) 5 (1.9%) 54 (20.0) 0 (0.0) Nass: - recent 1 (0.6%) 0 (0.0) 47 (17.4%) 2 (0.6%) Opium: - recent 8 (4.5%) 1 (0.4%) 50 (18.5%) 14 (4%)

Selected characteristics of subjects enrolled in the pilot study, by gender and urban/rural residence ExposureUrban men N=177 Urban women N=261 Rural men N=270 Rural women N=349 Body-mass index: - < (42.5%) 90 (36.7%) 51 (20.8%) 92 (26.7%) 115 (33.3%) 138 (40%) 118 (63.4%) 50 (26.9%) 18 (9.7%) 124 (50%) 72 (29%) 52 (21%) Cancer in relatives 22 (12.5%) 34 (13%) 73 (27%) 75 (21.5%)

Food groups Food group Women [n=86] Mean (95% CI) pMen [n=51] Mean (95% CI) p Vegetables (g/d) Urban Rural ( ) ( ) < ( ) ( ) 0.07 Legumes (g/d) Urban Rural ( ) ( ) ( ) 33.1 ( ) 0.04 Fruits (g/d) Urban Rural 343 ( ) ( ) < ( ) ( ) 0.04 Non-alcoholic beverages Urban Rural ( ) ( ) ( ) ( ) MeatUrban Rural 24.6 ( ) 21.8 ( ) ( ) 29.3 ( ) FishUrban Rural 5.5 ( ) 2.8 ( ) ( ) 6.5 ( ) 0.405

Plasma vitamin C Vitamin C µmol/l Urban Rural Women Men n=49n=33 n=38n=17 * *

Plasma carotenoids CarotenoidsMenWomen Unite RuralUrbanRuralUrban (n=33)(n=17)(n=48)(n=33) Alpha-carotene Beta-carotene Beta-cryptoxanthin Lycopene Lutein Zeaxanthin Total * * * * * * * *

Exposure to Polycyclic aromatic hydrocarbons (PAH) Measurement of 1-hydroxypyrene glucoronoid (1-OHPG) In 99 subjects Urinary levels of 1-OHPG ranging from 1 to 5 pmol/ml in 42% Urinary levels of 1-OHPG above 5 pmol/ml in 41% Age, sex, residence, smoking and opium explained 15% of the variance observed in urine 1-OHPG People in Gonbad and surrounding villages are exposed to very high levels of PAH due to others factors such as dietary factors

Logistical aspects and exposure measurement:summary High response rate High exposure to carcinogenic agents such as PAH Rural vs urban subjects are characterized by: lower socio-economic status Lower consumption of fresh fruits and vegetables Higher consumption of opium and nass Higher history of esophageal cancer in their first-degree relatives

Assessment of the interview’s reliability

Repeated interview on 150 subjects 2 months apart from the first one Calculation of Kappa correlation coefficients between the 2 interviews Protocol

Reliability of the interview Variable Agreement (%) Kappa Alcohol Smoking Opium consumption Nass consumption Cancer history 1001 Cancer in relatives Heartburn Regurgitation

Validity of self-reported opiate use comparing questionnaire responses to urine analysis 75 users and 75 non users Matched for age, sex, place of residence and ethnicity Analysis of opiate metabolite by a two-stage process: -Immunoassay -Gas chromatography-mass spectrometry Urine concentration of morphine and codeine>500 ng/ml= positive

Validity of self-reported opiate use comparing questionnaire responses to urine analysis Urine positive for Codeine or morphine Self-reported opiate use No Yes No67 8 Yes5 70 Sensitivity 93% Specificity: 89%

Tea temperature measurement

Protocol for measurements of tea temperature on 110 subjects In a freshly poured cup of tea, put a digital thermometer and wait until the temperature is 70  C and ask the subject to drink it. Is the subject able to drink the tea at 70  C? Yes  No  If the tea is too hot for the subject, wait until the temperature has dropped to 65  C and again ask the subject to drink it.

Comparison of repeated measurements of tea temperature on 110 subjects Temperature ( o C) at 2 nd measure 1 st measure < Total < Total Kappa=0.71

Dietary survey

protocol 130 subjects during 1 year period monthly 48h recall questionnaire (2 subsequent day) FFQ every 3 months Biological sample (four 24h urine and 2 blood samples

Spearman correlation coefficients for estimated food intake from the mean of 4 FFQ and the average of 12 24h-recalls Food groupMen (n=51)Women (n=86) p-value Vegetables0.62< < Legumes0.53< < Fruits < Dairy products0.69< < Cereals0.63< < Meat0.53< < Fish Fat0.54< < Sweets0.65< < Non-alcoholic beverages0.87< <0.0001

Conclusions High response rates: feasibility of recruiting large number of subjects in the Golestan region Repeated interview showed reliability of the main questionnaire Analysis of urine for morphine and codeine showed high sensitivity and specificity of the questionnaire on opium use The FFQ is able to obtain reliable information food consumed in Golestan province

Conclusions The method for obtaining information on tea temperature is reliable Significant between-subject variation for all of the main exposure of interest (diet, tea temperature and opium consumption) in the Golestan area

Perspective Establishment of a cohort of adults Follow-up for an initial period of 5 years Nested case-control studies

DDRC: Pr. R. Malekzadeh Dr. Porshams Dr. Eslami Dr. Sotoudeh NCI: Dr. S Dawsy Dr. C Abnet Dr. F. Kamangar IARC: Dr. P Boffetta Dr. P. Brennan Dr.S. Fahimi Acknowledgement