Biomedical subjects
Publications and source records attributed to A Hirsch.
Vulvectomy and posterior exenteration for advanced carcinoma of the vulva were performed on three patients using a two time-technique. The operative procedure and the patients' outcome are reported.
The stapedius reflex test, brainstem audiometry and the opto-vestibular tests for identifying acoustic neurinomas (AN) were evaluated and compared in a study of 21 patients with radiologically or surgically verified AN and a pure tone average not exceeding 60 dB HL. The stapedius reflex test results were interpreted according to the criteria developed at this clinic. The stimuli for the auditory brainstem response (ABR) were 2 kHz haversine waves and 4 kHz square waves. The vestibular examination consisted of a caloric test and the recording of eye-tracking and gaze nystagmus. In the cases studied the stapedius reflex test gave 1 false-negative result and ABR none. The ENG gave 3 false-negatives whereas the results of speech discrimination tests were misleading in no fewer than 1/3 of the cases. The results of the different tests were directly correlated but correlation coefficients did not exceed 0.65. Tumours larger than 15-20 mm showed a different test pattern than those below that size: stapedius reflex response, ABR and caloric response were eliminated and all of these patients had abnormal optomotor function. It is suggested that an optimal routine test procedure should consist of a pure tone audiogram, supplemented by ABR or the stapedius reflex test. Opto-vestibular tests may be of value in a preliminary estimation of tumour size.
Thirty-six histologically confirmed cases of pleural and peritoneal mesothelioma have been observed in a chest unit over a period of 53 months. The past asbestos exposure was assessed by a standardized questionnaire in all cases and the asbestos lung burden was determined by means of mineralogical analysis of lung-related biological specimens (sputum, bronchoalveolar lavage fluid, lung tissues) in 28 cases. The results of these two methods were found in good agreement. Past asbestos exposure has been definitely implicated in 17 cases and definitely eliminated in 10 cases. The results were inconclusive in other cases. The group with definite past asbestos exposure was different from the nonasbestos-exposed group by clinical, biological, pathological, and prognosis features that were analyzed. In cases without past asbestos exposure there were no other possible causative agents. Younger age and similar incidence in men and women suggest an environmental or natural disease.
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The carcinogenicity of untreated UICC chrysotile A, of acid (oxalic and hydrochloric)-leached UICC chrysotile A, of crocidolite and of JM 104 glass fibres has been studied by intrapleural injection into rats. This experiment, carried out on 304 animals, demonstrated that when more than 80% of the Mg had been leached from chrysotile fibres by either hydrochloric or oxalic acid, the proportion of pleural mesotheliomas was either nil or dramatically lower than that obtained with untreated chrysotile. The carcinogenic effect of crocidolite was higher than that of 43.7% oxalic acid-leached chrysotile. The proportion of mesotheliomas observed in animals injected with JM 104 glass fibres was similar to that in animals injected with fibres from which 63.8% had been leached with oxalic acid. These results indicate that with regard to the induction of pleural carcinogenicity by chrysotile fibres, not only size characteristics but also parameters such as chemical composition and physiochemical properties must intervene.
The study of this series of hospitalized patients extended over a period of 8 years, and the number of cases was estimated to be 1/8 of the total lung cancer population seen in the area serviced by the hospital. Distribution according to sex was in the ratio 18.6/1 and the mean age (60 to 62.8 years) was identical whatever the sex, smoking habits, presence or a absence of exposure to asbestos, and the histological type. The epidermoid type was more frequent, both in men (77.6 p. cent) and women (39.1 p. cent). A significant relationship with smoking was observed in the epidermoid form but not with adenocarcinomas. In men who smoked there were 78.6 p. cent of epidermoids against 53.8 p. cent in women, in whom the percentage of undifferentiated types (15.3 p. cent) exceeded that of the men (5.7 p. cent). In nonsmokers, adenocarcinomas represented 70 p. cent in women against 37.5 p. cent in men. In 9 p. cent of the cancers the patient had been exposed to asbestos during their occupation, the degree of exposure being low or moderate in 78 p. cent. The cancers were more frequently proximal (73 compared with 54.2 p. cent), bilateral (8 compared with 3.4 p. cent), derived from the inferior lobe (superior to inferior lobe ratio: 1.2 to 2.75), more often undifferentiated (20 against 4.2 p. cent), and less frequently of the epidermoid type (65 compared with 80.1 p. cent). The histological type is discussed as a function of the methodology of the histological diagnosis, and of the etiological factors, particular smoking and exposure to asbestos.
Fifty-nine fiberoptic examinations with endobronchial sampling, brushings, distal bronchial biopsy, and alveolar lavage were conducted during the course of recent pneumopathies in immunodeficient adults with malignant hemopathies (41 cases), solid tumors (7 cases), and other affections (11 cases). Diagnosis was established by fiberoptic bronchoscopy in 4 cases with specific locations of hemopathy or cancer, after bronchial biopsy, in 5 cases of mycoses, after bronchial biopsy, aspiration and/or alveolar lavage, in 4 patients with bacterial pneumonia after bronchial aspiration, and in 1 case of pneumocystosis, after distal biopsy. Diagnosis was not confirmed in the other cases. Mortality (50 p. cent) was similar in the diagnosed group and the group without confirmation of diagnosis. No significant complications due to the examination were observed, except for worsening of the respiratory condition in 7 patients with hypoxemia. The role of fiberoptic bronchoscopy in causing these alterations cannot be excluded. Fiberoptic bronchoscopy appears to be a safe examination except in patients with hypoxemia (PaO2 less than or equal to 50 mmHg). Distal biopsy appeared to be of less value than bronchial biopsy in these patients, as there was a positive correlation between the results of the latter examination and the macroscopic lesions observed in all cases.
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Different lung function tests have been studied in a group of 39 spray workers, with exposure of a few months to 20 years, in order to determine early impairments in ventilatory or gaseous exchange parameters. Lung function was assessed by conventional spirometric tests, plethysmographic measurement of lung volume, determination of arterial oxygen tension at rest and on exercise and measurement of single-breath diffusion of carbon monoxide. Asbestos exposure was assessed using a standardized questionnaire administered by an interviewer to determine length of exposure, and light microscopic examination to ascertain the number of ferruginous bodies in one sputum sample or in lung washing fluid. The results of the functional tests are expressed with respect either to duration of working exposure or to the number of ferruginous bodies. Restrictive ventilatory impairment with decrease in diffusion of carbon monoxide and increase in the oxygen alveolar-arterial difference on exercise was observed both in the group with 1-50 ferruginous bodies and in workers exposed for more than five years. The decrease in lung volume was approximately 10% when the length of asbestos exposure varied from 0-5 to 10-15 years, and 15% between those with no ferruginous bodies and those with more than 50. No obstructive profile was observed, even in heavy smokers. All function tests were altered equally. Plethysmography therefore appears to be a suitable technique for the follow-up of asbestos workers.
The relationship was studied between the presence in X-rays of one or several regions of straightness on the diaphragm, which interrupt or replace its normal curve, and the intensity, length and latency of asbestos exposure. Subjects were four groups in whom intensity of exposure, assessed by questionnaire and by ferruginous body counts, increased progressively. Diaphragmatic straightness increased with increasing intensity but not with length or latency of asbestos exposure.
When the disease is diagnosed early, pleurectomy or intrapleural inoculation of colloidal radioactive compounds may be effective. However, most mesotheliomas are already diffuse by the time they are diagnosed; and no treatment has been shown to be effective. Metastatic involvement of the chest wall results from any surgical procedure; however, pain may be controlled by pleurectomy and/or external-beam radiotherapy. Of the chemotherapeutic agents tested, doxorubicin appears to be the most promising. Large, cooperative, controlled trials are needed to evaluate the usefulness of one or a combination of the treatment methods described.
Two different methods have been tested for assessing retrospectively occupational exposure to asbestos dust in 80 cases with suspected asbestos-related thoracic diseases: 1) Occupational history was recorded by an interviewer using a standardized questionnaire. The patients were divided into three groups: those obviously exposed (E), those obviously not exposed (NE) and those with an inconclusive questionnaire (IQ). 2) Ferruginous bodies were isolated from lung washing fluid and counted under the light microscope. In the questionnaire groups, the proportions positive for ferruginous bodies in lung washing fluid were as follows: E, 29/33; NE, 1/7; IQ, 17/40. In cases positive for ferruginous bodies in lung washing fluid, the median numbers of bodies per ml of fluid were: E, 11.7 (range, 0.05-31,250); NE, 0.06; IQ, 1.1 (range, 0.06-350) Since the data provided by the two methods were in good agreement (P less than 0.001) for the E and NE questionnaire groups, the presence of ferruginous bodies in lung washing fluid is considered to be a good indicator of past exposure. In the IQ group, the monitoring of ferruginous bodies in lung washing fluid demonstrated exposure to asbestos in 43% of cases.
Asbestos fibres in respiratory tissues from 29 cases diversely exposed to asbestos dusts have been characterized, sized and counted using a transmission electron microscope. Comparison of data obtained by measurement of fibres in lung parenchyma and in parietal pleura samples showed the following: -- In each case, the proportion of chrysotile fibres (as opposed to amphiboles) was higher in parietal pleura than in lung parenchyma. (The proportion of chrysotile in pleura was greater than 90% in 30 of the 40 samples.) -- Fibres encountered in parietal pleura were shorter than those in the parenchyma. -- There was no evident correlation between numerical concentrations of fibres in lung parenchyma and those in parietal pleura. This study has shown that characteristics of asbestos retention in parietal pleura cannot be derived from measurements in lung parenchyma. On the basis of the cases analysed here, who were exposed to mixed types of asbestos dust, chrysotile seems to be the asbestos type retained almost exclusively in parietal pleural tissues. These findings might be taken into account when assessing the risk of pleural diseases (especially mesothelioma) attributable to each type of asbestos fibre.
Intrapleural injections of 20 mg of various mineral fibres were made to rats. Three types of fibres (chrysotile, crocidolite and glass fibres) were untreated; other chrysotile fibres were leached to different degrees. The results show that chrysotile is the most toxic of the three: animals died sooner and presented mesotheliomas earlier. With increased leaching, toxicity and carcinogenic effect decreased. Crocidolite is less toxic than untreated chrysotile but later produces as many mesotheliomas; with glass fibres, some mesotheliomas are observed. Small groups of animals were exposed to two types of irradiation before intrapleural injection of 2 mg of chrysotile. Whole-body irradiation was delivered to a third group of animals which were given asbestos-contaminated food. The paper analyses the synergistic action of these two insults.
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A matched survey of 55 full-time workers probably exposed to asbestos in an electricity-generating power station (exposed group) and of 53 unexposed workers in an automobile plant has been conducted. The asbestos risk in the power station was confirmed by the presence of airborne fibers in the range 0.1--6000 X 10(-9) g/m3 in the air sampled during the survey period and by the presence of FB in the sputa of 32.7% of the workers. The following parameters were significantly related to asbestos exposure in the study group: FB in the sputa, localized rectitude of the diaphragm, pleural thickening, pleural calcification, and the chest pain. Moreover, for all persons studied, gastrointestinal symptoms and recent hoarsening of the voice were significantly related to the number of FB in the sputa.