Long-term effect of COPD on patients with lung cancer

Abstract

18077 Background: Despite the association between chronic obstructive pulmonary disease (COPD) and lung cancer, their inter-relationship has not been studied. Their pathogenesis suggests that they may be a continuum of a single disease. The effect of COPD on outcomes in lung cancer has been primarily studied in surgical candidates in the peri-operative period, however long-term effects are unclear. We proposed to study the influence of COPD on overall survival in this patient population. Methods: After IRB approval a retrospective chart review was performed on patients with stage I and II, non-small cell lung carcinoma (NSCLC) diagnosed from 1994 through 2005. Data including demographics, smoking, treatment given, pulmonary function tests (PFTs) and survival were collected. Patients were classified as having COPD based on FEV1/FVC ratio of < 70%, and further graded by the percentage of predicted FEV1 value. Overall survival was computed by multiple linear regression and the p-value was calculated using the chi-square test. Results: Of the 399 patients with early stage NSCLC, 107 had PFTs evaluated before treatment of the cancer. Of these 42 (39%) did not have COPD, while 65 (61%) had COPD. Patients with COPD presented with a later stage (IB or II) as compared to those without COPD. After adjusting for age, stage, histology, treatment or smoking history, there was no difference in the overall survival among the two groups. The probability of 2-year overall survival for patients with mild, moderate, severe and very severe COPD was 100%, 79%, 77% and 62% respectively, compared with 72% for those without COPD. (p = 0.64). Conclusions: Patients with COPD presented with a later stage (IB or II) as compared to those without COPD. Despite this there was a trend toward an improvement in overall survival in patients with mild to moderate COPD that underwent surgical resection. This may be related, in part, to the beneficial effects of volume reduction of the diseased lung. The data are limited by low power that may have led to insignificant results. Further larger studies are required to better assess the relationship between COPD and lung cancer and its long term effects. No significant financial relationships to disclose.