Is staging mediastinoscopy necessary before stereotactic body radiotherapy for inoperable early stage lung cancer?

Patients with stage I non-small lung cancer (NSCLC) who are managed with stereotactic body radiotherapy (SBRT) do not routinely undergo mediastinal lymph node sampling, although a significant proportion of these patients can harbor metastatic subclinical mediastinal disease. For instance, results of a retrospective analysis by Sarwate et al., in which 59 patients with medically inoperable NSCLC, had pathologic mediastinal staging prior to SBRT consideration, indicated that 16% of patients had positive mediastinal disease, which prompted alternative treatment options (1).