Utility of mediastinoscopy in clinical stage I lung cancers at risk for occult mediastinal nodal metastases

Objective: The prevalence of mediastinal lymph node metastases is unknown for patients with clinical N0 lung cancer who are thought to be at high risk for occult nodal metastases. Further, the utility of mediastinoscopy in these patients is unknown. We performed a prospective trial to evaluate the utility of routine cervical mediastinoscopy for patients who may be at high risk of occult nodal metastases. Methods: From January 1, 2008, July 31, 2013, 90 patients with lung cancer with clinical stage T2N0 or T1N0 with standardized uptake value greater than 10 by positron emission tomography/computed tomography underwent routine cervical mediastinoscopy before lung resection. Biopsy of a minimum of 3 nodal stations at mediastinoscopy and a minimum of 4 nodal stations with lung resection was advised. The prevalence of nodal metastases at mediastinoscopy and lung resection was recorded. Results: Some 64% of patients with lung cancer were male with a mean age of 67.3 years. A total of 81 patients had clinical T2N0 and 9 patients had T1N0 with standardized uptake value greater than 10. Mean tumor size was 4.3 +/- 1.7 cm, and mean standardized uptake value was 13.5 +/- 6.8. One patient (1.1%) had occult metastases detected at mediastinoscopy. A total of 86 patients underwent surgical resection; 4 patients (4.6%) were upstaged to pN2, and 18 patients (21%) were upstaged to pN1. Of 90 patients with clinically staged N0 lung cancer by positron emission tomography/computed tomography, 5.6% (5) were upstaged to pN2 and 20% (18) were upstaged to pN1 (total nodal upstaging = 25.6%). Conclusions: Mediastinoscopy seems to have limited utility in these patients with T1 and T2 clinically staged N0 by positron emission tomography/computed tomography. Selective use of mediastinoscopy is recommended, along with thorough mediastinal lymph node evaluation in all patients at the time of lung cancer resection.