Acute exacerbation of idiopathic interstitial pneumonia complicated by lung cancer, caused by treatment for lung cancer

In 64 patients with lung cancer complicated by idiopathic interstitial pneumonia (IIP), we retrospectively studied the outcome of the treatment for lung cancer and clinical features of acute exacerbation of IIP after treatment for lung cancer. The incidence of acute exacerbation of IIP was 8.7% (2 of 23 patients) after anticancer chemotherapy, 14.3% (2 of 14 patients) after operation, and 25% (2 of 8 patients) after radiation therapy. Serum C-reactive protein level was significantly higher in the patients who developed acute exacerbation of IIP than in those who did not (CRP=5.12±2.27, 2.26±2.29, respectively). On the contrary, there were no differences in the levels of serum lactate dehydrogenase, white blood cell count, erythrocyte sedimentation rate, PaO2, and %VC between the two groups. Pathologic presentations of surgically resected lungs did not show significant differences in the activity of IIP between the two groups. Five of 6 patients who developed acute exacerbation of IIP died within 3 months after the treatment for lung cancer. We conclude that we should evaluate the activity of IIP more precisely using new markers for activity of IIP and on that basis select patients to be treated for lung cancer. (author)