Comparison of therapeutic results from radiofrequency ablation and stereotactic body radiotherapy in solitary lung tumors measuring 5 cm or smaller.

Ochiai, Satoru; Yamakado, Koichiro; Kodama, Hiroshi; Nomoto, Yoshihito; Ii, Noriko; Takaki, Haruyuki; Sakuma, Hajime

BACKGROUNDS This retrospective study was conducted to compare the clinical outcomes of radiofrequency ablation (RFA) with those of stereotactic body radiotherapy (SBRT) in patients with lung tumors. METHODS Local tumor progression, adverse events, and overall survival were compared in patients who underwent either RFA or SBRT for a single lung tumor measuring 5 cm or smaller. This study was approved by the institutional review boards of two institutions. Informed consent was waived. RESULTS During September 2009 to June 2012, 48 patients [30 males and 18 females, with a mean age ± standard deviation (SD) of 75.0 ± 7.5 years] underwent RFA at one institution and 47 patients (21 males and 26 females, with a mean age ± SD of 77.0 ± 7.5 years) underwent SBRT in another. The mean maximum tumor diameter ± SD was 2.0 ± 0.8 cm (range 0.6-3.9 cm) in the RFA group, and 2.1 ± 0.9 cm (range 0.8-4.7 cm, p = 0.539) in the SBRT group. The RFA and SBRT groups showed similar 3-year local tumor progression [9.6%, 95% confidence interval (CI) 3.6-23.9% vs. 7.0%, 95% CI 0.2-20.2%, p = 0.746] and overall survival rates (86.4%, 95% CI 69.2-94.3% vs. 79.6%, 95% CI 60.6-90.1%, p = 0.738). No factor significantly affected local tumor progression. A maximum tumor size of 2 cm was identified as a prognostic factor in both univariate and multivariate analyses. No death was related to treatment procedures. Major complication rates (Grade 3 adverse events) of the RFA (10.4%, 5/48) and SBRT (8.5%, 4/47, p > 0.999) groups were similar. CONCLUSION For lung tumor patients, lung RFA provided local tumor control and survival that were similar to those achieved using SBRT, with equal safety.