Lung cancer on the side of thoracoplasty performed 34 years earlier for pulmonary tuberculosis ; Results of respiratory function tests before and after lobectomy

Abstract

A 68-year-old man was referred to our department on Sept. 6, 1994, because his chest-X-ray film showed a mass shadow (4 cm in diameter) in the right lung suspected to be primary lung cancer. His right thorax had been deformed by thoracoplasty for pulmonary tuberculosis 34 years earlier. His preoperative lung function tests were : FVC = 1, 94 l, %FVC= 58.7%, FEU_1.0 = 0.96 l, FEV_1.0% =43.4%. Arterial blood gas analysis results were : PaCO₂= 48.1 mmHg, PaO₂= 77.0 mmHg at room air. Exercise respiratory function tests were : Vo₂max = 840 ml/mm, Vco₂= 800 ml/mm, and AT (anaerobic threshold) =15.3 ml/mm/kg. Lung perfusion scanning showed different distributions (left : right = 59.1% : 40.9%). Right lower lobectomy and mediastinal lymphnode sampling were performed. Severe adhesion of the pleura was observed and made the operation difficult. The operation time was 5 hours and intraoperative hemorrhage was 2, 300 ml. Pathological examination revealed moderately differentiated adenosquamous carcinoma and a pulmonary metastasis in the same lobe. The postoperative course was uneventful.
His postoperative lung function was examined one month and ten months after the operation. There was little change one month after the operation : FVC= 1.41 l, %FVC = 42.7%, FEV_1.0 = 0.90 l, FEV_1.0% =63.8%, PaCO₂=45.5 mmHg, PaO₂= 76.4 mmHg at room air and Vo₂max= 562 ml/min, Vco₂= 555 ml/min, and AT =10.3 ml/min/kg. However, lung perfusion scanning showed a different distribution (left : right= 91.8% : 8.2%). The results of the function tests can be divided into two group. The fist group are FEV_1.0 PaCo₂, and PaO₂, which were little changed after the operation. In the second group are FVC, VO₂max, Vco₂, AT, and lung perfusion, which changed at least 20% ; the degree of change seemed to correspond to the volume of resected lung. The patient's performance status (PS) and quality of life (QOL), which were conserved after the operation, seemed to be based on FEV_1.0, PaCo₂ and PaO₂.
In this patient lung resection on the side of impaired lung function caused little change of FEV_1.0 PaCO₂ and PaO₂, so preservation of his PS and QOL was possible.