Sputum screening for lung cancer in radon exposed uranium miners: a comparison of semi-automated sputum cytometry and conventional cytology.

Preparing for a prospective study on early lung cancer, correlation between semi-automated sputum cytometry (ASC) and conventional cytology (CY) was examined in 1517 former uranium miners with posterior-anterior and lateral chest roentgenograms. A hundred and twenty sputum specimens were classified as suspicious (grade II) and another 18 as highly suspicious (grade III) by ASC. Within grade III group, 9 samples were classified by CY as tumor cell positive, 7 severe, and 1 mild and 1 moderate dysplasias. In the group of grade II ASC, 7 were tumor cell positive, 27 classified as severe dysplasia or CIS, 20 as moderate and 19 as mild dysplasia. Twenty seven contained metaplasias and 18 were normal or inflammatory. Of the 1358 samples classified as benign (grade I) by ASC, only 5 samples were classified by CY as severe dysplasia, 6 as moderate and 34 as mild dysplasia, 173 as metaplasia, the others were normal or inflammatory. Twenty one samples were judged as inadequate for ASC and CY. At present, 23 tumors were found in final diagnosis. Sensitivity of ASC was 87% at a specificity of 92%, while CY, at high grade alterations as a threshold, had a sensitivity of 83% at 97% specificity. We conclude that, along with modern radiological procedures and molecular biological markers, ASC and CY should be included in a controlled prospective randomized study on early lung cancer.

Tracheobronchial obstruction due to silicosis.

Broncholithiasis can result in airway obstruction through the erosion of calcified lymph nodes into the bronchial lumen or by extrinsic compression of the tracheobronchial tree. We report an unusual case of broncholithiasis in a patient with silicosis who developed airway obstruction from endobronchial polypoid masses of granulation tissue adjacent to calcified mediastinal lymph nodes. The production of granulation tissue may have been the result of broncholiths in the early stages of erosion into the tracheobronchial tree. Efforts to ablate the endobronchial polyps using YAG laser phototherapy were only temporarily successful and surgical removal of the calcified mediastinal lymph nodes was required to halt further polyp growth. Surgical specimens grew Mycobacterium avium-intracellulare (MAI), a common pathogen in patients with silicosis. MAI may have contributed to the local inflammatory milieu provoking the exuberant tissue response.

Long-term follow-up observations of the therapeutic effect of PVNO on human silicosis.

The effect of PVNO treatment on human silicosis was observed in 7 cases over a period of 9 years lasting from 1965 to 1974. The drug was given intramuscularly and by way of inhalation, respectively. The comparison of the radiographs taken before, during and 3 years after the administration of PVNO showed that during treatment the tendency of fibrotic progression was delayed in 4 cases while 2 cases were slightly progressive, and one was markedly progressive, 3 years after discontinuation of the PVNO treatment, only one case remained stable, two cases were slightly and 4 cases markedly progressive. These observations indicate that PVNO treatment may have an effect on the delay and control of silicosis progression in a portion of patients, but after discontinuation of the treatment further progression is possible.

Silicosis in workers dealing with tonoko: case reports and analyses of tonoko.

We found three cases of pneumoconiosis among those workers who had been dealing with tonoko (a mineral powder) for more than ten years at a shop making wooden furniture in Sendai, Japan. In the factory the workers were exposed to tonoko dust and had been inhaling it for a long time. Until now, this disease has not been found in employees of furniture factories; and, furthermore, tonoko has not been regarded as a harmful material. Tonoko is a very fine mineral powder used widely in Japan for filling the grains of surfaces of wooden products. The three workers had scanty clinical symptoms; however, their chest x-ray films revealed disseminated nodulations throughout both pulmonary fields. One of the workers suffered from the complication of active pulmonary tuberculosis. Some of the analyses revealed that tonoko contained about 50% quartz. Accordingly, the disease is strongly suspected to be a sort of silicosis caused by inhalation of tonoko dust.