Background: There is little information on the clinical characteristics and outcomes of patients with surgically resected, incidentally detected lung cancers. Our hypothesis was that among patients with surgically resected non-small cell lung cancer (NSCLC), incidentally detected cancers were common, were less likely to require pneumonectomy, and were associated with better stage-adjusted survival.
Methods: Two hundred seventy-four patients with NSCLC who underwent surgical resection between 1999 and 2004 were studied. The clinical characteristics of patients with incidentally detected and symptomatic NSCLC were compared. A proportional hazards model was used to compare the stage-adjusted mortality rate of patients with incidentally detected and symptomatic NSCLC.
Results: One hundred patients (36%) had incidentally detected NSCLC. Patients with incidentally detected NSCLC had smaller and earlier-stage cancers, were less likely to undergo pneumonectomy (3% versus 13%, p = 0.005), and were more likely to have bronchioloalveolar carcinoma (15% versus 5%, p = 0.003). Patients with incidentally detected cancers had a stage-adjusted hazards ratio (HR) of mortality of 0.9 compared with symptomatic patients (0.6-1.4, p = 0.64). Patients with cancers detected incidentally on computed tomography (CT) had a stage-adjusted HR of 0.5 (0.2-1.5, p = 0.15).
Conclusions: Early-stage NSCLC is commonly detected incidentally. Patients with incidentally detected lung cancers are more likely to have bronchioloalveolar carcinoma histology, less likely to undergo pneumonectomy, and overall have similar stage-adjusted survival compared with symptomatic patients. Patients with cancers detected incidentally by CT scan may have better stage-adjusted survival, but our study was not sufficiently powered to detect this effect.