Bayan Hosseini

Profils professionnels et association avec le risque de cancer du poumon et de la vessie en Iran : une étude nationale de contrôle de cas: Ce jour, la plupart des preuves des risques de cancer professionnels proviennent d'études épidémiologiques menées dans des pays développés. Bien que l'Iran soit un pays industrialisé et que les travailleurs puissent être exposés à divers agents cancérigènes, seules quelques études ont été réalisés pour décrire les profils d'exposition et le risque de cancer associé. Cette thèse avait donc pour objectif de caractériser les expositions professionnelles en Iran et d’étudier le risque de cancer du poumon et de la vessie selon différents types de professions dans cette même région.D’après la littérature, nous avons constaté que les recherches épidémiologiques en milieu professionnel en Iran ont débuté au cours des dix dernières années. Les études sont limitées et ne permettent pas de fournir une vue d'ensemble complète des modèles d'exposition et des risques de cancer importants en Iran. La plupart des études épidémiologiques sont de petites tailles dans lesquelles les expositions étaient attribuées aux travailleurs en fonction de leurs intitulés d'emploi. Quelques études de surveillance de l'exposition ont été menées dans des industries telles que l’industrie pétrolière, métallurgique et la construction, où les expositions ont été mesurées à l'aide d'un échantillon unique par le biais d'un échantillonnage d'air individuel et stationnaire. Par la suite, nous avons évalué le risque de cancer du poumon et de la vessie selon les professions occupées, en utilisant les données de la large étude cas-témoins nationale IROPICAN. Au total, 717 cas de cancer de la vessie, 658 cas de du poumon et 3477 témoins ont été inclus de l'étude principale.Les données collectées incluaient des informations détaillées sur les antécédents professionnels, le statut tabagique, la consommation d'opium, ainsi que les antécédents de maladies respiratoires et des voies urinaires. Nous avons appliqué un modèle de régression logistique non conditionnelle pour évaluer le risque de cancer du poumon et de la vessie associé à des groupes de professions (CITP-68) et à certaines professions à haut risque pour le cancer du poumon et de la vessie, ajusté sur des facteurs de confusion connus.Chez les hommes, une association inverse entre certaines professions de type «col blanc» et le cancer du poumon a été observé, tandis que le travail d'opérateur d'usine et de machine, et les professions élémentaires étaient positivement associés au risque de cancer du poumon. Après ajustement sur le statut tabagique et la consommation d'opium, toutes les associations observées se sont atténuées. Nous avons également constaté un risque accru de cancer du poumon chez les hommes travaillant dans la construction et l'industrie pétrolière, ainsi que chez femmes agricultrices et boulangères.Une réduction du risque de cancer de la vessie a été observée pour certaines professions de type «col blanc», tandis que le travail d'opérateur d'usine et de machine, et les professions élémentaires étaient positivement associés au risque de cancer de la vessie. De même, un risque accru de cancer de la vessie a été observé chez les métallurgistes et parmi un groupe de professions présentant une forte probabilité d'exposition aux amines aromatiques. En résumé, les études sur les cancers professionnels en Iran doivent être étendues à la fois en termes d'études épidémiologiques et de surveillance de l'exposition. Par conséquent, une stratégie cohérente est nécessaire pour identifier les sources potentielles de données d'exposition dans les industries iraniennes et pour estimer le fardeau des cancers professionnels dans les professions à haut risque, tel que l'industrie pétrolière, la métallurgie et la construction, ainsi que les professions à haut risque d’exposition aux amines aromatiques. Le résultat de cette étude démontre également la nécessité d'une collaboration interdisciplinaire pour soutenir la recherche en milieu professionnel et le contrôle de l'exposition en Iran et au-delà.

PURPOSE: Buccal mucosa cancer (BMC), the most prevalent oral cancer (OC) site, is a multifactorial disease. With relatively high prevalence of periodontal diseases because of poor oral hygiene practices, oral health indicators remain an area of exploration in the Indian context for its association with BMC. METHODS: A total of 1,673 histologically confirmed cases and 1,601 frequency-matched controls from a hospital-based, multicenter case-control study was analyzed for the risk of BMC because of the oral hygiene indicators—denture use, number of decayed, missing, and filled teeth, and the Decayed, Missing, Filled Teeth (DMFT) score. Logistic regression models, adjusted for potential confounders like age, sex, rural-urban status, education, and tobacco and alcohol use (duration and frequency), were used to estimate odds ratios (ORs) and 95% CI. Analysis was further stratified on tobacco chewing and smoking. RESULTS: We obtained an increased risk of decayed (OR _{>2 decayed teeth} , 1.53; 95% CI, 1.09 to 2.16), missing teeth (OR _{>2 missing teeth} , 2.59; 95% CI, 1.99 to 3.37), and high DMFT scores (OR _{>3 DMFT score} , 2.07; 95% CI, 1.62 to 2.66). Similar results were observed on the stratified analysis. Protective effect was observed for teeth filling (OR _{>2 teeth-fillings} , 0.59; 95% CI, 0.34 to 1.03) and denture use (OR _{ever versus never used dentures} , 0.63; 95% CI, 0.47 to 0.85). CONCLUSION: Our findings suggest that DMFT score is associated with the risk of BMC and should be included in national oral health programs for prevention of OCs, along with other indicators of oral hygiene.

Globally, bladder cancer has been identified as one of the most frequent occupational cancers, but our understanding of occupational bladder cancer risk in Iran is less advanced. This study aimed to assess the risk of bladder cancer in relation to occupation in Iran. We used the IROPICAN case‐control study data including 717 incident cases and 3477 controls. We assessed the risk of bladder cancer in relation to ever working in major groups of the International Standard Classification of Occupations (ISCO‐68) while controlling for cigarette smoking, opium consumption. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CI). In men, decreased ORs for bladder cancer were observed in administrative and managerial workers (OR 0.4; CI: 0.2, 0.9), and clerks (OR 0.6; CI: 0.4, 0.9). Elevated ORs were observed in metal processors (OR 5.4; CI: 1.3, 23.4), and workers in occupations with likely exposure to aromatic amines (OR 2.2; CI: 1.2, 4.0). There was no evidence of interactions between working in aromatic amines‐exposed occupations and tobacco smoking or opium use. Elevated risk of bladder cancer in men in metal processors and workers likely exposed to aromatic amines aligns with associations observed outside Iran. Other previously confirmed associations between high‐risk occupations and bladder cancer were not observed, possibly due to small numbers or lack of details on exposure. Future epidemiological studies in Iran would benefit from the development of exposure assessment tools such as job exposure matrices, generally applicable for retrospective exposure assessment in epidemiological studies.

Background Globally, lung cancer is the most frequent occupational cancer, but the risk associated with the occupations or occupational environment in Iran is not clear. We aimed to assess occupations with the risk of lung cancer. Methods We used the IROPICAN nationwide case–control study data including 658 incident lung cancer cases and 3477 controls. We assessed the risk of lung cancer in relation to ever working in major groups of International Standard Classification of Occupations, high-risk occupations for lung cancer and duration of employment and lung cancer subtype among construction workers and farmers while controlling for cigarette smoking and opium consumption. We used unconditional regression logistic models to estimate ORs for the association between increased lung cancer risk and occupations. Results We observed elevated ORs for lung cancer in male construction workers (OR=1.4; 95% CI: 1.0 to 1.8), petroleum industry workers (OR=3.2; 95% CI: 1.1 to 9.8), female farmers (OR=2.6; 95% CI: 1.3 to 5.3) and female bakers (OR=5.5; 95% CI: 1.0 to 29.8). A positive trend by the duration of employment was observed for male construction workers (p< 0.001). Increased risk of squamous cell carcinoma was observed in male construction workers (OR=1.9; 95% CI: 1.2 to 3.0) and female farmers (OR=4.3; 95% CI: 1.1 to 17.2), who also experienced an increased risk of adenocarcinoma (OR=3.8; 95% CI: 1.4 to 9.9). Discussion Although we observed associations between some occupations and lung cancer consistent with the literature, further studies with larger samples focusing on exposures are needed to better understand the occupational lung cancer burden in Iran.

Introduction: The extent of exposure to occupational carcinogens is not well characterized in Iran, and little is known about the burden of occupational cancer. Objectives: This study aimed to describe exposure to occupational carcinogens and occupational epidemiology studies in Iran. Methods: Relevant studies up to January 2021 in Iran were identified through three databases (PubMed, Web of Science, and Google Scholar). Results: Forty-nine publications from 2009 to 2020 (one cohort, 11 case-control, 34 exposure monitoring studies, and three cancer burden studies) were included. The exposure monitoring studies were conducted mainly in the petroleum industry, metal industry, manufacturing of electronics, manufacturing of plastics, construction industry, and service industry. A few of the case-control studies also reported increased risk of cancers in relation to work in those industries. Conclusions: Occupational cancer epidemiology in Iran is at an early stage. Both epidemiological and exposure monitoring studies are generally limited in size to provide robust evidence of occupational cancer risks. A coherent strategy to estimate the occupational cancer burden in Iran should start with conducting epidemiological studies along with systematic monitoring of occupational carcinogens for use in hazard control and research.

Petroleum extraction and refining are major sources of various occupational exposures and of air pollution and may therefore contribute to the global cancer burden. This systematic review and meta-analysis is aimed at evaluating the cancer risk in petroleum-exposed workers and in residents living near petroleum facilities. Relevant studies were identified and retrieved through PubMed and Web of Science databases. Summary effect size (ES) and 95% confidence intervals (CI) were analysed using random effect models, and heterogeneity across studies was assessed (I²). Overall, petroleum industry work was associated with an increased risk of mesothelioma (ES = 2.09, CI: 1.58–2.76), skin melanoma (ES = 1.34, CI: 1.06–1.70 multiple myeloma (ES =1.81, CI: 1.28–2.55), and cancers of the prostate (ES = 1.13, Cl: 1.05–1.22) and urinary bladder (ES = 1.25, CI: 1.09–1.43) and a decreased risk of cancers of the esophagus, stomach, colon, rectum, and pancreas. Offshore petroleum work was associated with an increased risk of lung cancer (ES = 1.20; 95% CI: 1.03–1.39) and leukemia (ES = 1.47; 95% CI: 1.12–1.92) in stratified analysis. Residential proximity to petroleum facilities was associated with childhood leukemia (ES = 1.90, CI: 1.34–2.70). Very few studies examined specific exposures among petroleum industry workers or residents living in oil producing communities. The present review warrants further studies on specific exposure levels and pathways among petroleum-exposed workers and residents living near petroleum facilities.

Background: The International Agency for Research on Cancer (IARC) recently classified opium use as a Group 1 carcinogen. However, much remains to be studied on the relation between opium and cancer. We designed the Iranian Opium and Cancer (IROPICAN) study to further investigate the association of opium use and cancers of the head and neck, bladder, lung, and colon and rectum. In this paper, we describe the rationale, design, and some initial results of the IROPICAN Study. Methods: The IROPICAN is a multi-center case-control study conducted in 10 provinces of Iran. The cases were all histologically confirmed and the controls were selected from hospital visitors who were free of cancer, were not family members or friends of the cancer patients, and were visiting the hospital for reasons other than their own ailment. The questionnaires included detailed questions on opium use (including age at initiation, duration, frequency, typical amount, and route), and potential confounders, such as tobacco use (e.g., cigarettes, nass and water-pipe), and dietary factors. Biological samples, including blood and saliva, were also collected. Results: The validation and pilot phases showed reasonably good validity, with sensitivities of 70% and 69% for the cases and controls, respectively, in reporting opium use. The results also showed excellent reliability, with intra-class correlation coefficients of 0.96 for ever opium use and 0.88 (95% CI: 0.80, 0.92) for regular opium use. In the main phase, we recruited 3299 cancer cases (99% response rate) and 3477 hospital visitor controls (89% response rate). The proportion of ever-use of opium was 40% among cases and 18% among controls. Conclusion: The IROPICAN study will serve as a major resource in studies addressing the effect of opium on risk of cancers of the head and neck, bladder, lung, and colon and rectum.

Scant evidence exists to support the association of opium use with head and neck cancer, limited to the larynx and oral cavity. In a multicenter case‐control study—Iran Opium and Cancer study, we recruited 633 cases of head and neck squamous cell carcinoma (HNSCC) (254 lip and oral cavity, 54 pharynx, 327 larynx and 28 other subsites within the head and neck) and 3065 frequency‐matched controls from April 2016 to April 2019. Odds ratios (ORs) for opium use and 95% confidence intervals (95% CIs) were obtained using mixed‐effects logistic regression because of heterogeneity among centers. The adjusted OR (95% CI) for regular opium use was 3.76 (2.96‐4.79) for all HNSCC combined. Strong dose‐response effects were observed by frequency or amount of use, and duration of use. Regular opium uses significantly increased the risk of HNSCC of the pharynx, larynx and other subsites within the head and neck with OR (95% CI) of 2.90 (1.40‐6.02), 6.55 (4.69‐9.13) and 5.95 (2.41‐14.71), respectively. The observed associations were significant even among never tobacco smokers (including cigarette and water‐pipe smoking). Moreover, by the multiplicative interaction scale, the effect of opium use could be varied by cigarette smoking on HNSCC, 8.16 (6.20‐10.74). For the first time, the current study showed opium users have an increased risk of several anatomic subsites of HNSCC.