Treatment outcomes of percutaneous radiofrequency ablation versus adrenalectomy for adrenal metastases: a retrospective comparative study

Purpose To retrospectively evaluate the clinical outcomes of percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) in treatment of adrenal metastasis (AM), and to compare with adrenalectomy (Adx). Methods From June 2008 to August 2018, a total of 60 patients with AM treated at our hospital were retrospectively reviewed, of whom 29 treated by RFA (RFA group) and 31 by Adx (Adx group). The technical success, local tumor progression (LTP) and overall survival (OS) after the treatment were evaluated and compared. Results In RFA group, the first technical success was 72.4% and the second technical success was 86.2%. In Adx group, all the AMs were successfully resected. After 24.5 ± 19.1 months follow-up period, a total of 8 patients (6 in RFA group and 2 in Adx group) were detected LTP. The 1-, 2- and 3- LTP rates after treatment were 17.1%, 30.9% and 44.7% in RFA group, and 6.5%, 6.5% and 6.5% in Adx group, respectively ( P = 0.028). However, for AM ≤ 5 cm, the LTP between the two groups were comparable ( P = 0.068). The 1-, 2- and 3- OS rates after treatment for AM were 85.0%, 42.4% and 27.8% in RFA group, and 93.0%, 66.1% and 52.3% in Adx group, respectively ( P = 0.057). RFA offered shorter treatment time (23.6 ± 16.9 vs. 155.6 ± 58.8 min, P < 0.001), shorter hospital stay (7.8 ± 3.9 vs. 15.0 ± 4.9 days, P < 0.001), and lower hospital cost ($3405.7 ± 1067.8 vs. $5248.0 ± 2261.3, P = 0.003) than Adx. Conclusion In comparison with Adx, percutaneous US-guided RFA, as an alternative treatment, is feasible and effective in controlling AM, especially in AM ≤ 5 cm in diameter.