How to diagnose and manage lung cancer patients with interstitial pneumonia -Surgical management-

Abstract

Purpose. Idiopathic interstitial pneumonia (IIP) is associated with an increased risk of lung cancer. However, the contribution of anticancer therapies is unclear because these therapies, including surgery, may trigger acute exacerbation (AE), and are confounded by the progressive nature and poor prognosis of IIP. The purpose of the present study was to identify the predictors of both AE and long-term survival after surgical resection for lung cancer. Methods. We retrospectively analyzed the cases of 1,763 non-small cell lung cancer patients who underwent pulmonary resection between January 2000 and December 2009 after presenting with a clinical diagnosis of IIP at 61 institutions in Japan. Results. AE occurred in 9.3% of the patients; the mortality rate was 43.9%. A multivariate analysis identified the following seven risk factors for AE: anatomical surgical resection, male sex, a history of AE, preoperative steroid use, a high serum level of sialylated carbohydrate antigen KL-6, the usual appearance of interstitial pneumonia on CT, and a reduced percent predicted vital capacity (%VC). Unfortunately, no effective prophylactic medications could be identified. The overall 5-year survival rate was 40%, which was poorer than that in the historical control. The multivariate analysis revealed that wedge resection, %VC <80% and lower lobe cancer were predictors of poor survival. Of note, wedge resection reduced the incidence of death due to respiratory failure but resulted in a poorer long-term prognosis than lobectomy because of the higher incidence of cancer recurrence. We further developed a simple risk scoring system for predicting AE by giving weight to each of the seven risk factors. Conclusions. We identified seven risk factors for AE and three predictors of a poor prognosis after surgical resection for lung cancer associated with IIP. We further developed a simple risk scoring system for predicting AE. Using this risk scoring system, surgeons can preoperatively assess the risk of AE in each patient and may choose an appropriate surgical procedure in routine clinical practice.