Laryngeal and hypopharyngeal cancers and occupational exposure to formaldehyde and various dusts: a case-control study in France.

OBJECTIVES: A case-control study was conducted in France to assess possible associations between occupational exposures and squamous cell carcinomas of the larynx and hypopharynx. METHODS: The study was restricted to men, and included 201 hypopharyngeal cancers, 296 laryngeal cancers, and 296 controls (patients with other tumour sites). Detailed information on smoking, alcohol consumption, and lifetime occupational history was collected. Occupational exposure to seven substances (formaldehyde, leather dust, wood dust, flour dust, coal dust, silica dust, and textile dust) was assessed with a job exposure matrix. Exposure variables used in the analysis were probability, duration, and cumulative level of exposure. Odds ratios (ORs) with their 95% confidence intervals (95% CIs) were estimated by unconditional logistic regression, and were adjusted for major confounding factors (age, smoking, alcohol, and when relevant other occupational exposures). RESULTS: Hypopharyngeal cancer was found to be associated with exposure to coal dust (OR 2.31, 95% CI 1.21 to 4.40), with a significant rise in risk with probability (p<0.005 for trend) and level (p<0.007 for trend) of exposure. Exposure to coal dust was also associated with an increased risk of laryngeal cancer (OR 1.67, 95% CI 0.92 to 3.02), but no dose-response pattern was found. A significant relation, limited to hypopharyngeal cancer, was found with the probability of exposure to formaldehyde (p<0.005 for trend), with a fourfold risk for the highest category (OR 3.78, 95% CI 1.50 to 9.49). When subjects exposed to formaldehyde with a low probability were excluded, the risk also increased with duration (p<0.04) and cumulative level of exposure (p<0.14). No significant association was found for any other substance. CONCLUSION: These results indicate that exposure to formaldehyde and coal dust may increase the risk of hypopharyngeal cancer.

[3 different malignancies of the aerodigestive tract after chronic abuse of cannabis products]. / Dreiunterschiedliche Malignome des Aerodigestivtraktes nach chronischem Abusus von Cannabisproduken.

The occurrence of multilocular malignant tumors in the upper aerodigestive tract in young patients with known marijuana abuse has been described by other authors. A case of a 28-year-old man who was known to abuse alcohol, nicotine and cannabis for some years is presented. He suffered simultaneously from a squamous cell carcinoma of the hypopharynx with bilateral cervical metastases, an adenocarcinoma of the transverse colon and a primary hepatocellular carcinoma. This case is the first reported that shows the occurrence of three separate malignant tumors with different histologies in the aerodigestive tract which could be related to a chronic abuse of cannabis.

[Occupational exposure to hazardous substances and risk of cancer in the area of the mouth cavity, oropharynx, hypopharynx and larynx. A case-control study]. / Berufliche Exposition gegenüber Schadstoffen und Krebsrisiko im Bereich von Mundhöhle, Oropharynx, Hypopharynx und Larynx. Eine Fall-Kontrollstudie.

A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in Heidelberg and Giessen (FRG) provided information on occupational factors in 200 patients and 800 controls (adjusted to sex, age and area of living; 4:1 matched design). The number of subjects exposed to wood dusts, organic chemicals, coal products or to cement was significantly elevated in the tumour group. An increased risk for head and neck cancer was observed after exposition to wood dust (RR = 2,2), organic compounds (RR = 2,4), coal products (RR = 2,7) and especially to cement (RR = 4,4). The cancer risk due to cement exposition showed a positive correlation to the duration of exposition and remained significantly elevated after adjustment for alcohol and tobacco consumption.

A study of the relationship between mouthwash use and oral and pharyngeal cancer.

As part of a larger case control study on a male veteran population at risk (drinking and smoking) for oral and pharyngeal cancer, 95 cases and 913 controls provided complete histories in a questionnaire that included data on mouthwash use. Analysis revealed no significant differences in the frequency of mouthwash users in cancer cases versus controls. In addition, no significant differences could be found between users and nonusers of mouthwash in relation to age or smoking and drinking habits. When a logistic regression analysis was performed to simultaneously remove the effects of age, or smoking and drinking habits, while controlling for all other factors, oral and pharyngeal cancer did not appear related to mouthwash use. In this study there is no evidence that mouthwash is a risk factor in the development of oral and pharyngeal cancer in males.