Assessment of pulmonary function after lobectomy for lung cancer--upper lobectomy might have the same effect as lung volume reduction surgery.

OBJECTIVE Lung volume reduction surgery (LVRS) in well-selected patients with severe emphysema results in postoperative improvement in symptoms and pulmonary function. Experience with LVRS suggests that predicted postoperative FEV(1.0) may be underestimated after lobectomy in patients with lung cancer and emphysema. As most of the patients with lung cancer have more or less emphysematous changes in the lungs, we assumed that lobectomy would achieve the same effect as LVRS even in patients without chronic obstructive pulmonary disease on the pulmonary function test. We assessed changes in pulmonary function in terms of 'volume reduction effect' after lobectomy for lung cancer. METHODS Forty-three patients underwent right upper lobectomy (RUL), 38 patients left upper lobectomy (LUL), 39 patients right lower lobectomy (RLL), and 38 patients left lower lobectomy (LLL). Pulmonary function tests were performed preoperatively and 6 months to 1 year after surgery. RESULTS Percent change in FEV(1.0) after lobectomy was -6.9+/-16.1% in RUL group, -11.2+/-16.9% in LUL group, -14.7+/-9.8% in RLL group, and -12.8+/-9.5% in LLL group. We evaluated the correlation between a preoperative FEV(1.0)% of predicted and percentage change in FEV(1.0) after lobectomy. There were no significant relationships between these variables in RLL or LLL group. In contrast, there were significant negative relationships between these variables in RUL and LUL groups. Correlation coefficients were r = -0.667, p < 0.0001 for RUL and r = -0.712, p < 0.0001 for LUL. In RUL and LUL groups, patients with a higher preoperative FEV(1.0)% of predicted had a more adverse percentage change in FEV(1.0) after surgery. In addition, all 13 patients with a preoperative FEV(1.0)% of predicted <60% in RUL and LUL groups had an increase in FEV(1.0) postoperatively. Patients with a lower preoperative FEV(1.0)% of predicted had a greater 'volume reduction effect' with an increase in FEV(1.0) after upper lobectomy. CONCLUSION Upper lobectomy might have a volume reduction effect.