Purpose: Lung cancer is the most common cause of cancer death in both men and women in our country. It has been estimated that there will be 6,000 lung cancer deaths every year in Greece. However, many patients with bronchogenic carcinoma also have coexistent obstructive lung disease. In these patients, preoperative prediction of functional status after lung resection is mandatory. The aim of our study was to determine the effect of lung resection on postoperative spirometric lung function.
Patients and methods: 112 patients underwent spirometric pulmonary tests preoperatively, and at 3 and 6 months after their operation. The predicted postoperative forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) were calculated using the formula of Juhl and Frost: predicted postoperative FEV1 (or FVC)=preoperative FEV1(or FVC) x[1-(S x 0.0526)], where S=number of segments resected. Statistical significance was defined as a p value < 0.05.
Results: The functional percentage losses at 6 months for lobectomies and pneumonectomies were 7.34% and 34.89% for FVC and 7.72%; and 32.53% for FEV, respectively. The linear regression analysis derived from the correlation between predicted and measured FEV1 resulted in 2 equations for lobectomy and pneumonectomy. The first, for lobectomy, was: FEV1POSTOP=0.00211 + 0.896660 x FEV1PREOP; and the second, for pneumonectomy, was: FEV1POSTOP=0.145 + 0.65318 x FEV1PREOP.
Conclusion: We conclude that our formulas are a reliable method for predicting postoperative respiratory function of the patients with lung cancer.