Thorax 1988;43:496 Spontaneous pneumothorax due to metastatic carcinoma of the rectum

Spontaneous pneumothorax is a rare complication of both primary and secondary malignant tumours of the lung. We report the first case caused by metastatic carcinoma of the rectum. Case report A 59 year old man presented with left sided chest pain of sudden onset. He gave a six month history of dry cough with one episode of haemoptysis. Ten years previously he had undergone an abdominoperineal resection for a Duke's C adenocarcinoma of the rectum. A spontaneous pneumo-thorax was diagnosed and confirmed by a chest radiograph which also suggested a left hilar abnormality (figure). The pneumothorax was managed by intercostal chest drainage but the lung failed to re-expand. Bronchoscopy showed a tumour in the left main bronchus close to its bifurcation. Biopsy of this lesion revealed a poorly differen-tiated adenocarcinoma. Other investigations showed no contraindication to resection. At operation the left lung was found to be totally collapsed with a 4 x 5 cm tumour in the lower lobe, infiltrating close to the visceral pleura at the base. As the tumour extende