Occult Carcinoma of the Bronchus

The term “occult carcinoma” is applied to those patients with carcinoma of the bronchus at an in situ or early invasive stage who have carcinoma cells in their sputum but have no recognizable evidence of tumour in the chest radiograph. In eight such patients at the Toronto General Hospital, the lesion was localized and treatment instituted. Our experience with these eight patients can be compared with that of 27 patients described in two similar studies. The lesions were commonly symptomatic. Localization, although sometimes difficult, was accomplished using information obtained during bronchoscopy and bronchography. The prognosis following adequate resection appeared excellent. No patient died of carcinoma during the post-treatment follow-up period, which was continued for a minimum of 18 months. Pathological evidence indicates that bronchial carcinoma at this occult stage can be diagnosed cytologically, is rarely multifocal and, as a localized neoplasm, is amenable to curative therapy.     

Carcinoma of Bronchus and the Smoking Habit in Rhodesian Africans

Comparison of the smoking habits of 32 adult male Africans with carcinoma of the bronchus and 32 controls showed that 87.5% of the patients with lung cancer were cigarette smokers compared with only 22% of the controls. The distribution of histological types of growth confirmed findings by other workers.The absence of atmospheric pollution in Rhodesia makes it likely that cigarette-smoking is the most important causative factor in the aetiology of lung cancer among Rhodesian Africans. Further work is needed to determine the level of consumption of cigarettes and type of smoking habits which lead to a serious risk of cancer.     

Scintillation Scanning of Lungs in Preoperative Assessment of Carcinoma of Bronchus

Lung scans with the use of macroaggregated human serum albumin labelled with technetium-99m were carried out in 52 patients before thoracotomy.Forty-three patients had carcinoma of the bronchus. Tumours less than 2 cm. in diameter on the chest radiograph were not detected. Larger tumours showed defects in perfusion, ranging in size from the mass seen on the chest radiograph to almost absent perfusion of the entire lung. The extent of the defect in perfusion was closely related to involvement of the pulmonary vessels at the hilum by distortion, compression, or invasion by the tumour. Bronchial obstruction played a less important part in producing the defects.The larger the defect in perfusion the greater was the involvement of the hilar and mediastinal structures and the more extensive was the surgery required. When perfusion of the affected lung was less than one-third of the total the tumour was found to be unresectable.