Survival Outcomes of RFA, SBRT, or Sublobar Resection for Patients with Clinical Stage I NSCLC

Survival Outcomes of Treatment with Radiofrequency Ablation, Stereotactic Body Radiotherapy, or Sublobar Resection for Patients with Clinical Stage I Non–Small-Cell Lung Cancer: A Single-Center Evaluation

Clinical question
Is there a difference in outcome of patients with stage I non-small cell lung cancer (NSCLC) who underwent either radiofrequency (RF) ablation, stereotactic body radiotherapy (SBRT), or sub-lobar resection (SLR)?

Take-away point
SLR achieved the longest survival. However, after statistical adjustment, there were no significant outcome differences in over all survival (OS) and progression-free survival (PFS) among the treatment groups except in 1 model. RF ablation or SBRT may be used as alternative treatments in select patients with early stage NSCLC.

Reference
Iguchi T, Hiraki T, Matsui Y, et al. Survival Outcomes of Treatment with Radiofrequency Ablation, Stereotactic Body Radiotherapy, or Sublobar Resection for Patients with Clinical Stage I Non-Small-Cell Lung Cancer: A Single-Center Evaluation. J Vasc Interv Radiol. 2020;31(7):1044-1051.

Click here for abstract

Study design
Retrospective, single center

Funding Source
None reported.

Setting
Academic Hospital, Okayama, Japan.

Summary

A retrospective study which compared the 5 year overall and progression free survival rate of 289 patients with stage I NSCLC who underwent SLR (n=193), or either RF ablation (n=38) or SBRT (n=58), when they refused surgery or were deemed poor surgical candidates. Patients in the SLR grouped achieved the longest OS and PSF according to Kaplan-Meier curves. However after propensity score correction, there were no significant differences in either OS (P=0.701) or PSF (P=0.091) rates based on the Kaplan-Meier curves.

The reported survival rates of the SLR group were longer compared to the RF and SBRT groups. The 5 year OS of RF ablation, SBRT, and SLR were 25% to 61%, 25% to 83%, and 60.5% to 89.6% respectively. The median survival time of RF ablation, SBRT, and SLR were 29 to 67 months, 39-62 months, and not reached or 7.8 years, respectively. The median hospital stays for RF ablation, SBRT, and SLR were 6.5, 6, and 16 days, respectively. No adverse events (AEs) of grade 3 or higher occurred in either RF ablation or SBRT groups compared to the eight grade 3 and three grade 4 AEs with in the SLR group.

The results of this study further emphasized that RF ablation or SBRT may be used as alternative methods of treatment in select patients with early stage NSCLC.

Commentary

The increased utilization of CT imaging has led to earlier diagnosis of primary lung cancer, and where reduction surgery (such as SLR) has been the treatment of choice for small, localized and peripheral lesions. Some patients – the elderly, those with end-organ disease and medical comorbidities – are not good surgical candidates. RF ablation and SBRT are alternative treatments with shorter hospitalizations and comparable survival rates to that of surgery. The main limitations in this study were the retrospective design, small cohort, single center, and irregularity of follow up protocols. Additionally, there were missing PF testing data (one of the 14 independent variables used to calculate the propensity score), especially among the RF ablation group, although the authors did identify FEV1 as a confounding variable after hazard models were adjusted. Selection bias for stratification was also identified, as, for example, patients with interstitial pneumonia are known to be ill suited for RFA or SBRT treatment. Other factors, such as insurance coverage, amenability to repeat treatment, and tumor characteristics, should be considered, as they can impact the appropriateness of each procedure. However, large, multi-centered randomized controlled trials could better compare these interventions in the future.

Post Author
Ashkan Berenji, DO
Diagnostic and ESIR Resident, PGY-3
Baylor College of Medicine
@BerenjiAshkan