Objectives: The aim of the present study was to evaluate the feasibility and diagnostic value of repeat mediastinoscopy as part of the response-evaluation protocol of 2 phase II multimodality studies for either stage IIIA/B non-small cell lung cancer or small cell lung cancer.
Methods: From January 1991 through December 1998, 104 patients (79 men and 25 women) with stage IIIA/B non-small cell lung cancer (84 patients) or small cell lung cancer (17 patients) were enrolled in 2 different multimodality trials and underwent remediastinoscopy after induction chemoradiotherapy. The median age was 56 years (range, 34-72 years). Sensitivity, specificity, accuracy, and predictive values of remediastinoscopy were calculated by using standard definitions.
Results: Remediastinoscopy was feasible in 98% of cases. Mortality was nil, and morbidity very low (1.9%). Lymph node downstaging (N0) was observed in 84 patients, persisting N2 disease was observed in 15 patients, and N3 disease was observed in 5 patients. Sensitivity was 61%, specificity was 100%, and accuracy was 88%. Positive predictive and negative predictive values reached 100% and 85%, respectively. According to the results of remediastinoscopy, 81 patients underwent surgical intervention, 3 refused the operation, and an unnecessary thoracotomy could be avoided in the remaining 20.
Conclusions: Remediastinoscopy provides a histologic proof of mediastinal downstaging with high diagnostic accuracy, is technically feasible with low morbidity, and still remains a valuable tool, even in an era of highly sophisticated imaging and endoscopic procedures. Persisting nodal disease at repeat mediastinoscopy carries a poor survival in the majority of cases because of occult metastases, so that indication for surgical intervention in such an unfavorable group of patients should be evaluated very carefully.