Reply to A.V. Louie et al
Authors: Hiran C. Fernando
Journal: Journal of Clinical Oncology (2014)

I read with interest the comments by Louie et al 1 regarding our report 2 describing the results of a randomized trial of sublobar resection (SR) with or without brachytherapy for stage I lung cancer.Their comments addressed three areas to which I would like to respond.First, they discussed the value of lymph node staging in high-risk patients undergoing surgery and requested information about the adequacy of staging nodal disease in our study. 2This was in fact reported in an earlier analysis. 3Among 210 evaluable patients for whom data were available for that secondary analysis, 64% underwent a video-assisted thoracoscopic surgery (VATS) resection and 36% an open resection.Segmentectomy was only performed in 27% of patients and wedge resection in 73%.There were no differences between the degree of nodal evaluation among patients treated with VATS or thoracotomy.However, significant differences were observed between patients who underwent a segmental or wedge resection in terms of nodal upstaging (9% v 1%) and number of lymph node stations sampled (three v one), respectively.Considering that only credentialed surgeons participated in the study, we were disappointed to see that 41% of patients treated with wedge resection had no lymph node sampling at all, compared with 2% of those treated with segmentectomy.It should be emphasized that the type of lymph node dissection performed was not mandated in the study, because this was deemed a high-risk operable population.A second point raised in their comments was the impact of treatment-related mortality and morbidity in high-risk patients treated with SR, which the authors perhaps use as an argument in favor of stereotactic ablative radiotherapy (SABR).Probably the most influential multicenter trial in North America for SABR in high-risk stage lung cancer is RTOG (Radiation Therapy Oncology Group) 0236. 4 This study involved 55 patients deemed medically inoperable.Conversely, in Z4032, eligible patients were those deemed high risk for lobectomy but still considered operable.It is noteworthy that in an analysis of selection criteria for these two National Cancer Institute studies of stage I lung cancer, pretreatment forced expiratory volume in 1 second (61.3% v 53.8%) and carbon monoxide diffusing capacity (61.6% v 43.7%) were superior for SABR patients compared with those undergoing surgery. 5This demonstrates that patients are not comparable between clinical trials.There was no treatment-related mortality after SABR in RTOG 0236, but 30-and 90-day mortality rates were also low, at 1.4% and 2.7%, after SR in Z4032. 4,6Not unexpectedly, grade Ն 3 adverse events occurred in a lower percentage of SABR patients compared with those undergoing SR (16.3% v 30.6%) when these two studies are compared.It is reasonable to consider these numbers when counseling patients.Third, in the conclusion of their letter, Louie et al 1 argue that SABR should be considered a primary modality for high-risk patients.I strongly disagree with this statement.A number of studies now support the role of SABR as the gold standard for medically inoperable patients, but this does not translate to SABR being considered the primary modality for high-risk operable patients currently treated