Regional lung function in long-term survivors after chemotherapy for small cell lung cancer.

In order to evaluate the regional lung function in patients with small cell lung cancer with long-term survival, we measured the regional lung function in 17 patients. We studied the patients with 81m-krypton ventilation scans and 99m-technetium perfusion scans, as well as measurements of static lung volumes (VC, RV, TLC), flow volume indices (FEV1, FVC, MEF50), and carbon monoxide diffusing capacity (DLCO). We found both the ventilation and the perfusion of the affected lung to be slightly but significantly lower (P less than 0.05), while no obvious ventilation or perfusion defects could be identified at the former tumor site. The static volumes of the lungs, the FVC and the FEV1 were within predicted normal values, while a significant decrease was seen in the PEF, MEF50, and DLCO. It is concluded that patients with small cell lung cancer who obtain complete remission with normalization of the chest X-ray and long-term survival after 18 months of intensive chemotherapy also have a nearly normal lung function.