Association of SDF-1 and CXCR4 Polymorphisms With Susceptibility to Oral and Pharyngeal Squamous Cell Carcinoma.

BACKGROUND/AIM: Long-term exposure to betel quid (BQ)-, cigarette-, and alcohol-induced chronic inflammation is a crucial risk factor for oral and pharyngeal squamous cell carcinoma (OPSCC) progression. We analyzed the genotypes of stromal-cell-derived factor-1 (SDF-1) and CXC-chemokine receptor-4 (CXCR4) and determined the association between their polymorphisms and the risk of OPSCC. MATERIALS AND METHODS: This study consisted of 452 patients with pathologically proved OPSCC and 424 sex- and age-matched cancer-free controls. The genotypes of SDF-1 and CXCR4 were detected through the TaqMan real-time polymerase chain reaction (PCR) method. RESULTS: Our data indicated that the C allele and C/C genotypes of CXCR4 were significantly associated with OPSCC [adjusted odds ratio (AOR)=1.41, 95% confidence interval (CI):1.02-1.96, p=0.037 and AOR=1.51, 95% CI:1.05-2.17, p=0.028, respectively] and OSCC (AOR=1.41, 95%CI:1.00-2.00, p=0.049 and AOR=1.49, 95%CI:1.01-2.20, p=0.044, respectively) risk. Patients with genetic polymorphisms of the genotype combination SDF-1/CXCR4 had a higher risk of OSCC (p trend=0.033). We analyzed the effects of CXCR4 genetic variants on susceptibility to OPSCC in patients with different risk habits of BQ chewing, tobacco smoking and alcohol consumption, and revealed that C/T+T/T genotypes exerted an increased risk only in patients with one (AOR=2.68, p=0.036) or two risk habits (AOR=2.02, p=0.027) compared to patients with the C/C genotype. CONCLUSION: We concluded that CXCR4 C>T can be used as a genetic marker of susceptibility to OPSCC, particularly in OPSCC patients with one or two types of risk habits with a synergistic effect.

Cancer Risks of Hexavalent Chromium in the Respiratory Tract.

Hexavalent chromium (Cr(VI)) compounds are recognized as carcinogens in the respiratory tract, giving rise to cancers of the lung, nose and nasal sinuses, especially in certain occupational environments. Inhalation exposure of Cr(VI)-containing particles, dusts and fumes commonly occurs in chromium-related occupational environments, such as chromium production, plating, welding of chromium-containing metals and alloys, electroplating, chromium-containing pigments and paints. Epidemiological surveys of chromium compounds have shown strong associations between exposure to Cr(VI) and mortality due to lung cancer, as well as positive associations with cancers of the nose and nasal cavity. Nasal symptoms, such as nasal irritation, ulceration and perforation of the nasal septum, nasal turbinate engorgement and hypertrophy, are important signs for the early diagnosis of lung cancer and cancers of the nose and nasal cavity in those with an occupational history of Cr(VI) exposure. Cr(VI) exposure in the workplace remains a serious problem as a cause of lung cancer and cancers of nose and nasal cavity, especially in relatively small enterprises that use chromium compounds. Appropriate protection for workers should be considered in occupations that involve exposure to chromium compounds.

Molecular Pathogenesis of Chewable Tobacco.

In Pakistan, extensive use of several precarious chewable tobacco formulations has made oral cancer the second leading malignancy. Selection of literature was done by a survey of studies published from 1990 to 2017 mainly, from PUBMED and few from other search engines, on naswar, gutka, areca nut and betel quid, which included published reviews, original articles and other data sources on chewable tobacco, its epidemiology, pathological implications, and psychological effects. These studies have revealed that the chemicals in these formulations bind and mutate DNA of oral mucosa through down regulating cellular repair pathways and upregulating genetic networks associated with pathogenesis. Areca nut, having aercoline (the major alkaloid) causes carcinogenicity, mutagenicity, and genotoxicity of oral mucosa through increased production of growth factors and corticotrophin-releasing hormone, and genetic alteration in expression of CASP8, APAF-1, BAX, BAD, and upregulation of caspas-3. Gutka addiction leads to precancerous lesions resulting in characteristic facial abnormalities, following trismus. Naswar, in addition to oral cancer, causes adverse cardiovascular events by reducing glutathione per oxidase (GPx) and super-oxide dismutase (SOD), serum levels of HDL, whereas, increasing the ratio of cholesterol, LDL, triglycerides and LDL-C/HDL-C. Betel quid (Paan), causes psychoactivity affecting central and autonomic nervous systems leading to dependence with decreased cognition, euphoria, sweating, salivation, palpitation, heightened alertness and zest to work. Metabolically, cardio-acceleration, cortical desynchronisation of EEG, elevated plasma noradrenaline and adrenaline were found. This review highlights the corrosive effects of various most popular chewable tobacco formulations; and damage done by their cocktail of carcinogenic substances and added ingredients, leading to oropharangeal cancer.

Cytochrome p450 metabolism of betel quid-derived compounds: implications for the development of prevention strategies for oral and pharyngeal cancers.

Betel quid (BQ) products, with or without tobacco, have been classified by the International Agency for Research on Cancer (IARC) as group I human carcinogens that are associated with an elevated risk of oral potentially malignant disorders (OPMDs) and cancers of the oral cavity and pharynx. There are estimated 600 million BQ users worldwide. In Taiwan alone there are 2 million habitual users (approximately 10% of the population). Oral and pharyngeal cancers result from interactions between genes and environmental factors (BQ exposure). Cytochrome p450 (CYP) families are implicated in the metabolic activation of BQ- and areca nut-specific nitrosamines. In this review, we summarize the current knowledge base regarding CYP genetic variants and related oral disorders. In clinical applications, we focus on cancers of the oral cavity and pharynx and OPMDs associated with CYP gene polymorphisms, including CYP1A1, CYP2A6, CYP2E1, and CYP26B1. Our discussion of CYP polymorphisms provides insight into the importance of screening tests in OPMDs patients for the prevention of oral and pharyngeal cancers. Future studies will establish a strong foundation for the development of chemoprevention strategies, polymorphism-based clinical diagnostic tools (e.g., specific single-nucleotide polymorphism (SNP) "barcodes"), and effective treatments for BQ-related oral disorders.

Carcinoma of the pharynx and tonsils in an occupational cohort of asphalt workers.

BACKGROUND: We investigated a possible association between pharyngeal/tonsillar carcinoma and mixed carcinogen exposures in an asphalt roll company in Italy that used asbestos until 1979, when a new factory was built using a different production process. METHODS: We evaluated all workers involved in the entire production history of the company, divided into two subcohorts based on exposure status (workers in the original factory, 1964-1979, and those who worked only in the new factory, 1980-1997). We ascertained the vital status of the study population in February 2001. RESULTS: Among the subset of workers in the earlier subcohort, there were five deaths from pharyngeal/tonsillar carcinoma for a standardized mortality ratio of 21 (95% confidence interval = 8.8-51). No cases were recorded among workers hired after 1979. CONCLUSION: The increased standardized mortality ratio for this relatively rare cancer among workers exposed before 1979 may have been due to carcinogenic exposures at the plant.

Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review.

PURPOSE: The role of occupational risk factors in oral and pharyngeal cancer is not well known and is possibly underestimated. This quantitative review summarizes epidemiological findings on exposure to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx. METHODS: A systematic literature search was performed. We analyzed 63 publications: 8 from case-control studies and 55 from cohort studies. For agents with at least five available studies with homogenous exposure, a series of meta-analyses was conducted to provide quantitative pooled estimates of risks, using random effect models. RESULTS: Exposure to asbestos (meta-RR 1.25; 95% CI 1.10-1.42) and to polycyclic aromatic hydrocarbons (meta-RR 1.14; 95% CI 1.02-1.28) was found to be associated with oral and pharyngeal cancer risk. On the other hand, no association was found with exposure to solvents in general (meta-RR 0.98; 95% CI 0.77-1.23) but the strong heterogeneity between studies suggested differences in exposures. The small number of studies with homogeneous exposure did not allow meta-analyses for specific solvents. CONCLUSIONS: Future investigations should overcome common weaknesses of past studies, in terms of sample size, characterization of exposure, and classification of cancer sites.

Coffee and tea intake and risk of head and neck cancer: pooled analysis in the international head and neck cancer epidemiology consortium.

BACKGROUND: Only a few studies have explored the relation between coffee and tea intake and head and neck cancers, with inconsistent results. METHODS: We pooled individual-level data from nine case-control studies of head and neck cancers, including 5,139 cases and 9,028 controls. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI), adjusting for potential confounders. RESULTS: Caffeinated coffee intake was inversely related with the risk of cancer of the oral cavity and pharynx: the ORs were 0.96 (95% CI, 0.94-0.98) for an increment of 1 cup per day and 0.61 (95% CI, 0.47-0.80) in drinkers of >4 cups per day versus nondrinkers. This latter estimate was consistent for different anatomic sites (OR, 0.46; 95% CI, 0.30-0.71 for oral cavity; OR, 0.58; 95% CI, 0.41-0.82 for oropharynx/hypopharynx; and OR, 0.61; 95% CI, 0.37-1.01 for oral cavity/pharynx not otherwise specified) and across strata of selected covariates. No association of caffeinated coffee drinking was found with laryngeal cancer (OR, 0.96; 95% CI, 0.64-1.45 in drinkers of >4 cups per day versus nondrinkers). Data on decaffeinated coffee were too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk (OR, 0.99; 95% CI, 0.89-1.11 for drinkers versus nondrinkers). CONCLUSIONS: This pooled analysis of case-control studies supports the hypothesis of an inverse association between caffeinated coffee drinking and risk of cancer of the oral cavity and pharynx. IMPACT: Given widespread use of coffee and the relatively high incidence and low survival of head and neck cancers, the observed inverse association may have appreciable public health relevance.

Maté drinking and oral and oro-pharyngeal cancer: a systematic review and meta-analysis.

In Latin America, maté is consumed as a beverage regularly. Among the cancers that are associated with maté drinking is oral and oro-pharyngeal cancer, incidence of which is high in the region. In order to further understand this association between maté drinking and the risk of oral and oro-pharyngeal cancer, we performed a systematic review and meta-analysis of related studies. All relevant studies published in English as original articles up to June 2009 were identified through a literature search using PubMed and Medline and by reviewing the references from the retrieved articles. Four case-control studies done in Latin America were identified. There were 879 maté users and 1128 non- or low-maté users in those studies with a total of 566 oral and oro-pharyngeal cancers. The adjusted association between maté drinking and oral and oro-pharyngeal cancer was significant within 3 of those studies. Meta-analysis yielded a significant summary odds ratio (OR) of 2.11 (95% confidence interval=1.39-3.19). Population Attributable Risk for maté drinking was 16%. While the epidemiological data indicate that maté users have an increased risk of oral and oro-pharyngeal cancer, little is known about whether this increased risk is due to the high temperature of the beverage when it is consumed or due to certain carcinogenic constituents that are present in maté. More human and animal studies are needed before a conclusion can be made on the oral and oro-pharyngeal carcinogenic risk of maté to humans.

[Occupation as a risk factor for oral and pharyngeal cancer]. / La ocupación como factor de riesgo del cáncer oral y de faringe.

INTRODUCTION AND OBJECTIVES: Oral and pharyngeal cancers represent the fifth most common cancer type and the seventh cause of deaths by cancer worldwide. Few studies have assessed the risks associated with occupational exposure and in many cases the results are contradictory. The objective of this study is to determine the association between occupational exposure to carcinogenic substances and risk of oral and pharyngeal cancer (including nasopharynx and hypopharynx) through a systematic review. MATERIAL AND METHODS: A literature search was carried out in MEDLINE (PubMed) and EMBASE. The articles were selected by two independent investigators on the basis of inclusion and exclusion criteria (sample size, publication type, etc.). RESULTS: 10 original articles were included, all with a case-control design. The results showed that a prolonged exposure to formaldehyde may increase the risk of nasopharyngeal and hypopharyngeal cancer, whilst other chemical products were not associated with these tumours. The exposure to different types of particles (such as wood dust in nasopharyngeal cancer) and smoke of various origins has also been associated with several oral and pharyngeal tumours. CONCLUSIONS: The literature reviewed shows that occupational exposure to formaldehyde may be associated with an increased risk of nasopharyngeal and hypopharyngeal cancer. The results regarding other occupational exposures are not consistent, therefore additional studies with more statistical power and better design are needed to ascertain if occupation is really a relevant risk factor for these types of cancer.

Cancer of the mouth and pharynx, occupation and exposure to chemical agents in Finland [in 1971-95].

The objective of this article was to find associations between cancer of the mouth and pharynx, occupation and chemical exposure. A cohort of Finns born between 1906 and 1945 was followed-up for 46.8 (21.5 in males and 25.3 in females) million person-years during 1971-95. Incident cases of cancer of the mouth and pharynx (n = 2,708) were identified in a record linkage with the Finnish Cancer Registry. The Census occupations in 1970 were converted to chemical exposures with a job-exposure matrix (FINJEM). Cumulative exposure (CE) was calculated as the product of prevalence, level and duration of the exposure. Standardized incidence ratio (SIR) was calculated for each of the 393 occupations, and for CE categories of the 43 chemical agents, using total Finnish population as reference. Relative risks (RR) comparing various CE-categories with unexposed ones were defined for selected agents by Poisson regression analysis. Elevated SIRs were observed among lawyers, authors, journalists, performing artists, musicians, electronics and telefitters, painters (building), building hands, dockers, unskilled labourers and hotel porters in males and private secretaries, dressmakers, shoemakers and cobblers, waiters, pursers and stewardesses in females. The multivariate analyses showed high RRs for high exposure to aliphatic and alicyclic hydrocarbons, pesticides and alcohol. In conclusion, occupations with high SIRs were mostly the ones with high consumption of alcohol. Exposure to solvents and possibly to pesticides, engine exhaust, textile dust and leather dust may increase the risk of cancer of mouth and pharynx.

Prevalence and associated factors of betel quid use in the Solomon Islands: a hyperendemic area for oral and pharyngeal cancer.

Chewing betel quid is a popular habit in tropical areas. It is also a known fact that oral cancer is one of the most common cancers in the Solomon Islands, where betel quid chewing is prevalent. This study explores the prevalence of betel quid chewing in the Solomon Islands and related sociodemographic factors. A community-based survey was designed for the entire Solomon Islands people. Information on sociodemographic characteristics, habits of betel quid chewing, smoking, and drinking was collected by trained interviewers with a standard questionnaire. The prevalence of betel quid chewers, smokers, and drinkers was 76.8%, 53.0%, and 36.8%, respectively. Betel quid use was closely associated with smoking (aOR = 3.95; 95% CI: 1.87-8.33). Seventh-Day Adventist subjects were less likely to chew betel quid (aOR = 0.08; 95% CI: 0.04-0.18). Efforts to reduce habitual betel quid consumption and smoking might be of benefit in reduction of oral cancer incidence.

The synergistic effect of cigarette taxes on the consumption of cigarettes, alcohol and betel nuts.

BACKGROUND: Consumption of cigarettes and alcoholic beverages creates serious health consequences for individuals and overwhelming financial burdens for governments around the world. In Asia, a third stimulant--betel nuts--increases this burden exponentially. For example, individuals who simultaneously smoke, chew betel nuts and drink alcohol are approximately 123 times more likely to develop oral, pharyngeal and laryngeal cancer than are those who do not. To discourage consumption of cigarettes, the government of Taiwan has imposed three taxes over the last two decades. It now wishes to lower consumption of betel nuts. To assist in this effort, our study poses two questions: 1) Will the imposition of an NT$10 Health Tax on cigarettes effectively reduce cigarette consumption? and 2) Will this cigarette tax also reduce consumption of alcoholic beverages and betel nuts? To answer these questions, we analyze the effect of the NT$10 tax on overall cigarette consumption as well as the cross price elasticities of cigarettes, betel nuts, and alcoholic beverages. METHODS: To establish the Central Bureau of Statistics demand function, we used cigarette, betel nut, and alcoholic beverage price and sales volume data for the years 1972-2002. To estimate the overall demand price elasticity of cigarettes, betel nuts, and alcoholic beverages, we used a seemingly unrelated regression analysis. RESULTS: We find that the NT$10 health tax on cigarettes will reduce cigarette consumption by a significant 27.22%. We also find that cigarettes, betel nuts, and alcoholic beverages have similar inherent price elasticities of -0.6571, -0.5871, and -0.6261 respectively. Because of this complementary relationship, the NT$10 health tax on cigarettes will reduce betel nut consumption by 20.07% and alcohol consumption by 7.5%. CONCLUSION: The assessment of a health tax on cigarettes as a smoking control policy tool yields a win-win outcome for both government and consumers because it not only reduces cigarette consumption, but it also reduces betel nut and alcoholic beverage consumption due to a synergistic relationship. Revenues generated by the tax can be used to fund city and county smoking control programs as well as to meet the health insurance system's current financial shortfall.

Chemoprevention of cancer of the upper respiratory tract of the Syrian golden hamster by aerosol administration of difluoromethylornithine and 5-fluorouracil.

Research aimed at identifying effective chemopreventive compounds active against carcinogenesis of the upper respiratory tract (URT) has been largely unsuccessful. We are addressing this problem by efforts at agent identification and by using aerosol delivery. Two compounds, difluoromethylornithine (DFMO) and 5-fluorouracil (5-FU) were investigated. DFMO is an irreversible inhibitor of ornithine decarboxylase, an enzyme important in cell proliferation. It has been used widely by oral administration for chemoprevention. 5-FU is a pyrimidine analog used extensively as a chemotherapeutic agent. It is generally administered i.v. and can cause considerable toxicity. However, aerosol administration for therapy of lung cancer in humans has been reported to be without adverse effects (Tatsumura et al., Br J Cancer 1993;68:1146-9). The experimental model used herein entailed six intratracheal administrations of methylnitrosourea (MNU) to hamsters. Each of the test agents was started about 1 week after MNU and was continued for 29 weeks with DFMO. Infiltrating squamous cell carcinomas of the URT occurred in 92% of the controls and were reduced by 50% in animals receiving DFMO (P = 0.0001). The experiment with 5-FU was of shorter duration being terminated 20 weeks after MNU. Thirty percent of the controls had infiltrating carcinomas and were reduced by 60% in animals receiving 5-FU (P = 0.0274). Both compounds resulted in a significant increase in the percent of cancer-free animals. These two agents may have selected use in subjects at high risk of cancer of the URT.

[Farm compost polluted water may induce pharyngo-esophageal, gastric and liver carcinoma in the chicken].

OBJECTIVE: To study farm compost polluted water that may induce pharyngo-esophageal, gastric and liver carcinoma in chickens. METHODS: 280 chickens were randomized into 4 groups: experiment group 100 chickens fed with compost water + NaNO(2) by stomach tube. The other 180 were evenly randomized into 3 control groups (60 each), fed with compost water, NaNO(2) and tap water in the same way. The farm compost was prepared with corn stalks, rice straws, excreta of men and livestock. The compost water, after being nitrosified and acidified, was fed through stomach tube 5 - 7.5 ml/session, twice a week. Besides, a solution consisting of the respective formula of each group added with 3 - 4 L water with pH adjusted to 3 - 4 by 1N HCL was given ad lib to all chickens in each group for 26.5 months. RESULTS: In the experiment group, there were pharyngo-esophageal carcinoma 16 (16.3%), gastric adenocarcinoma 5 (10.4%) and liver carcinoma 3 (6.3%), in contrast to none in the 3 control groups, showing significant differences (P < 0.01, P < 0.01, P < 0.05). CONCLUSION: Successful simulation of the layout of esophageal carcinoma high morbidity area and the mimic of chicken gastric fluid strongly support our compost etiological hypothesis that the nitrosified and acidified compost water are carcinogenic, very well causing esophageal, gastric and liver carcinoma.

Sugarcane farming, occupational solvent exposures, and the risk of oral cancer in Puerto Rico.

The work history information from a population-based case-control study conducted in Puerto Rico was analyzed using a job exposure matrix to investigate the relationship between occupational exposures and cancers of the oral cavity or pharynx. After adjustment for age, alcohol, smoking, and residence in a logistic model, the risk for cancer of the oral cavity, but not the pharynx, was significantly elevated among farm workers in the sugarcane industry (OR = 4.4, 95% CI = 1.4-13.6). An exposure-response trend was seen for cumulative exposure to solvents, with an OR = 3.2 (95% CI = 0.8-12.6) in the highest exposure category. The overall contribution to the risk of cancer of the oral cavity or pharynx associated with occupational exposures in Puerto Rico appears to be small, however, the elevated risks were seen among sugarcane farmers and subjects with high cumulative exposure to solvents.

Role of alcohol dehydrogenase 3 and cytochrome P-4502E1 genotypes in susceptibility to cancers of the upper aerodigestive tract.

Alcohol is a recognized risk factor for upper aerodigestive tract (UAT) cancers, but the mechanism by which alcohol causes cancer remains obscure. Ethanol is oxidized to acetaldehyde (the suspected carcinogenic agent in alcohol) by alcohol dehydrogenases (ADHs) and cytochrome P-4502E1 (CYP2E1), both of which exhibit great inter-individual variability in activity. The hypothesis that these polymorphisms influence susceptibility to alcohol-related cancers remains poorly documented. We investigated whether ADH(3) and CYP2E1 DraI and RsaI genotypes modified the risk of UAT cancers among 121 oral cavity/pharyngeal cancer patients, 129 laryngeal cancer patients, and 172 controls, all French Caucasians. Cancer risks and gene-alcohol interactions were analyzed by unconditional logistic regression, accounting for potential confounders. ADH(3) genotype was not associated with UAT cancer. In contrast, a 2-fold risk of oral cavity/pharyngeal (OR = 2.0, 95% CI 1.0-3.9) and laryngeal (OR = 1.8, 95% CI 1.0-3.5) cancers was observed for carriers of the CYP2E1 DraI C variant allele compared with other individuals. The risk associated with the CYP2E1 RsaI c2 variant allele also increased for oral cavity/pharyngeal cancer (OR = 2.6, 95% CI 1.0-6. 6). The effects of ADH(3) or CYP2E1 genotype and alcohol or tobacco were independent. The highest risk of oral cavity/pharyngeal cancer was observed among the heaviest drinkers (>80 g/day) with the CYP2E1 DraI C allele (OR = 5.8, 95% CI 1.9-18.2) or the CYP2E1 RsaI c2 allele (OR = 7.2, 95% CI 1.4-38.2) compared with lighter drinkers with other genotypes. Our study suggests that CYP2E1 genotype modifies the risk of UAT cancers, but due to the low frequency of CYP2E1 variant alleles, large-scale studies are needed to confirm our findings.

Time trends in the mortality rates for tobacco- and alcohol-related cancers within the oral cavity and pharynx in Japan, 1950-94.

Mortality data of oral cancer over 40 years in Japan were analyzed to investigate time trends of the disease site-specifically and discuss the relation between these trends and the changing patterns of consumption of tobacco and alcohol beverages. Mortality rates were adjusted to the world standard population. In the males, overall oral cancer (ICD-9: 141-149) mortality rates have increased consistently from the lowest value of 1.25 (per 100,000 per year) in 1956 to 2.40 in 1992. The rates for females were constantly lower than those for males, and formed a modest peak of 0.96 in 1979. Regarding site-specific mortality rates, tongue cancer (141) presented a decreasing trend, while oro/hypopharyngeal (146, 148) and mouth (143-145) cancers showed increasing patterns, particularly in males. When the changing patterns of male truncated rates for ages 35-64 were compared with those of the annual consumption of cigarette and alcohol per capita, the time trend of oro/hypopharyngeal cancer mortality was analogous to cigarette consumption rather than to alcohol consumption, mouth cancer vice versa, and tongue cancer was not related to tobacco or alcohol consumption. The present findings suggest that tobacco and alcohol have different site-specific effects on the development of cancers within the oral cavity and pharynx.

Hodgkin's disease, pharyngeal cancer, and soft tissue sarcomas in Danish paper mill workers.

Several studies have indicated an increased cancer risk among paper mill workers, based on rather few cancer cases. The authors studied cancer incidence in a large historical cohort of 14,362 Danish paper mill workers, employed at any time between 1943 and 1990, and followed up until December 31, 1993. Men had an increased risk of pharyngeal cancer (15 observed (obs), standardized incidence ratio (SIR) 1.99, 95% confidence interval (CI) 1.11-3.29). With two additional cases among women, 11 of 17 cases were located in the tonsils. Men also had an increased risk of Hodgkin's disease (18 obs, SIR 2.01, 95% CI 1.19-3.18). Women had an increased risk of soft tissue sarcomas (nine obs, SIR 2.33, 95% CI 1.06-4.43), with a high risk among female paper sorters (eight obs, SIR 3.98, 95% CI 1.71-7.84). The study thus supports some studies' observations of an increased risk of Hodgkin's disease in paper mill workers. The detailed reporting of cancer cases in paper mill workers have furthermore revealed a risk of pharyngeal cancer together with a risk of soft tissue sarcomas in paper sorters.

[Occupational exposure to paint, lacquer and solvents, and cancer risk in the area of the upper aero-digestive tract]. / Berufliche Exposition gegenüber Farben, Lacken und Lösungsmitteln und Krebsrisiko im Bereich des oberen Aerodigestivtraktes.

So far, only few studies exist that have investigated the influence of occupational exposure to paint and lacquer on the risk of cancer in the upper aerodigestive tract. Based on data from the Heidelberg case control study which enrolled 369 patients with carcinomas of the upper aerodigestive tract and 1476 randomized control subjects, the relative risk of head and neck cancer in patients exposed to paint, lacquer and varnish was analyzed. The relative risk (RR) of squamous cell cancer (after adjustment for possible alcohol and tobacco effects) was significantly increased for the larynx (RR = 2.3) and the oral cavity (RR = 3.6). However, this risk was not increased for the pharynx. Our findings and a critical analysis of the literature provide evidence that chronic exposure to paint, varnish and lacquer is a definite risk factor for cancer of the upper aerodigestive tract. Further studies are required to confirm these findings, and to identify more precisely toxic substances encountered in the workplace.