Impact of Preoperative Endoscopic Ultrasound on Non-small Cell Lung Cancer Staging

Abstract

To determine if the addition of preoperative endoscopic ultrasound (EUS) to non-small cell lung cancer staging can reduce the proportion of patients in whom malignant mediastinal lymph nodes (inoperable disease) are discovered at surgery. All patients with lung cancer who underwent mediastinoscopy or thoracotomy for cancer diagnosis, staging, or treatment from 1999 to 2005 were identified. Patients who had undergone preoperative EUS were designated as the EUS group. The control group was composed of similar patients who had not undergone preoperative EUS, and were frequency matched to those in the EUS group in a 3:1 ratio by preoperative cancer stage. The proportion of patients in whom malignant mediastinal lymph nodes were diagnosed at surgery was the primary outcome. Forty-four patients (average age, 67.8 years) met criteria for the EUS group, and 132 patients (average age, 67.4 years) were selected as control subjects. Overall, in the EUS group, 3 of 44 patients (6.8%) were found to have malignant mediastinal lymph nodes at surgery, compared with 41 of 132 patients (31.1%) in the control group (p = 0.003). In patients undergoing thoracotomy for cancer resection, 3% in the EUS group, compared with 20% in the control group, were found to have malignant mediastinal lymph nodes at surgery (p = 0.01). There was also a trend toward lower yield of mediastinoscopy done for cancer diagnosis or staging in the EUS group (p = 0.08). Preoperative EUS in lung cancer patients may reduce unnecessary surgery at which advanced inoperable disease is discovered.