Effectiveness of radiofrequency ablation therapy for patients with unresected Stage IA non-small cell lung cancer

Approximately 20% of patients with resectable non-small cell lung cancer (NSCLC) are treated nonsurgically. To compare the clinical outcomes between nonsurgical patients receiving radiofrequency ablation (RFA) alone and those receiving no treatment (NT), we assessed RFA effectiveness in terms of survival using the surveillance, epidemiology, and end-results (SEER) database.

Using the SEER registry process, we identified 5268 patients who were ineligible for the surgical treatment between 2004 and 2015. Overall survival (OS) and cancer-specific survival (CSS) were compared between the groups using propensity score matching (PSM), inverse probability of treatment weight (IPTW), and overlap weight analysis. In addition, an exploratory analysis was conducted to determine RFA treatment effectiveness based on clinically relevant patient subsets.

Of the 5268 patients, 189 (3.6%) received RFA. The OS and CSS in these patients were significantly better than those in the NT group (P < 0.0001). RFA was associated with a 16-month median OS improvement. Both OS and CSS improved in the nonsurgical patients (hazard ratio [HR], 0.695, 95% confidence interval [CI], 0.585-0.826, P < 0.0001; HR, 0.636; 95% CI, 0.505-0.800, P < 0.0001). The 1-, 3-, and 5-year OS in the unmatched RFA and NT groups were 84.2%, 49.0%, and 29.4% vs. 62.8%, 31.1%, and 17.1%, respectively (P < 0.001). PSM, IPTW, and overlap weight analysis showed comparable results. The odds of receiving RFA decreased with larger tumor size (>1, ≤2 cm, odds ratio [OR], 0.623, 95% CI, 0.402-0.966; >2, ≤3 cm, OR, 0.300, 95% CI, 0.186-0.483) compared to tumor size s1 cm (P < 0.05).

RFA improves unresected stage IA NSCLC patient survival. Our results are limited by the retrospective nature of the study; however, we believe that our findings are noteworthy for recommending local ablative therapy.