Asbestos body content of the larnyx in asbestos workers. A study of five cases.

Occupational exposure to asbestos has been epidemiologically associated with carcinoma of the larynx; however, no search for or quantitation of laryngeal asbestos bodies has been performed. This report concerns an autopsy study of five patients with occupational asbestos exposure and proven asbestos-associated pulmonary disease in whom histologic sections of the larynx were examined and a digestion-concentration technique was used to isolate and quantitate the asbestos bodies in the remaining laryngeal tissues. No dysplastic epithelial changes were present in the mucosa. Asbestos bodies were recovered from two of the five larynges but from none of ten larynges obtained from autopsy controls.

Pulmonary fibrosis, carcinoma, and ferruginous body counts in amosite asbestos workers. A study of six cases.

The Tyler Asbestos Workers Program is a continuing study of 1,105 former amosite asbestos workers. This report includes a study of six former workers, five of whom died and had autopsies, and one who underwent a lobectomy. Five of these men were exposed to asbestos for three months or less. Four had lung cancer, and one a rectal carcinoma. All were cigarette smokers. Ferruginous (asbestos) body content of the upper and lower lobes of the lungs was quantitated by a digestion technic. Tissue sections from upper and lower lobes were independently quantitated for fibrosis and ferruginous bodies, and chest roentgenograms were examined for interstitial fibrosis. (Control lung tissue was obtained from consecutive autopsies of 52 adults who did not have a known occupational exposure to asbestos.) Relatively low ferruginous body counts (less than 700/g lung tissue) were associated with mild degrees of fibrosis, and higher counts (greater than 10,000/g) with moderate to severe fibrosis. Mild to moderate pulmonary fibrosis could be identified on tissue sections before interstitial changes were detectable by chest roentgenograms.

The clinical significance of ferruginous bodies in sputa.

The clinical significance of ferruginous bodies in sputa was examined in a study of 674 former asbestos workers. Data from occupational histories and smoking behavior questionnaires, chest radiographs, spirometric measurements and counts of ferruginous bodies were obtained as part of a five-year surveillance program. Statistical analysis demonstrated that ferruginous bodies found in the sputa were significantly related to radiographic findings of interstitial pulmonary disease and pleural fibrosis and to spirometric findings of restrictive lung disease. Age and cigarette smoking were also found to be related to the presence of ferruginous bodies.

The Tyler Asbestos Workers Program. I. A medical surveillance model and method.

An asbestos-exposed worker who smokes cigarettes has a high risk of developing cancer of the lung. One thousand ninety-five former workers at a plant manufacturing asbestos (amosite) insulation products were exposed to high levels of asbestos dust concentrations in the atmosphere. The workers have been identified and located. A semi-annual medical surveillance program has been developed with National Cancer Institute support. Examination of the worker includes the following: history (questionnaire), physical examination, sputum cytopathology, chest roentgenogram, pulmonary function studies, and other tests. Emphasis has been placed on understanding the role of sputum cytopathology in a cancer control program in former asbestos workers.

Ferruginous bodies in sputa of former asbestos workers.

Routine cytopathologic examinations were performed at six-month intervals on sputum specimens from 628 former asbestos workers and 138 control patients. The occurrence of ferruginous bodies in sputa is found to increase as a logarithmic function of the length of occupational exposure to asbestos in workdays. No significant association is found between the occurrence of ferruginous bodies and the worker's age, smoking history, degree of cellular epithelial atypia, or time since last exposure. We conclude that the presence of ferruginous bodies in sputa is evidence of probable significant occupational exposure to asbestos dust. Their absence does not indicate lack of exposure. We can also conclude that routine cytopathology procedures are sufficient for the detection of ferruginous bodies in sputa.

Results of treatment of primary carcinoma of the lung. Analysis of 3,000 cases.

Three thousand patients with primary carcinoma of the lung entered in the Armed Forces Central Medical Registry are reported. Forty-one per cent had squamous cell, 28.5 per cent adenocarcinoma, 25.2 per cent small cell/undifferentiated, and 4.9 per cent miscellaneous cell types. When first seen, 71.1 per cent had no organ metastases and 50.6 per cent no lymph node metastases. Over-all survival rate was 18.2 per cent at 5 years and 14.5 per cent at 10 years. Survival following definitive resection, palliative resection, definitive radiation, palliative radiation, and chemotherapy was determined both in the presence of mediastinal nodal involvement and in the absence of mediatinal nodal involvement. Where resection for cure could be carried out, 5 year survival rates of 48.8 per cent were possible. The factors affecting this improved outlook in our military population are discussed and, in general, appear to be related to a ready accessibility of medical care and the necessity, because of global commitments, of establishing an early diagnosis. Cell type ecerted some influence on survival, but the major determinant appeared to be the absence of involved nodes at the time of the operation.