セツジョ フノウ ハイガン ニ タイスル ハイ ラジオハ ショウシャク リョウホウ : シュヨウ セイギョリツ ト カンレン インシ ナラビニ ガッペイショウ ニ カンスル ケントウ

Purpose: To retrospectively analyze the tumor control rates, factors related to tumor progression, and complications ofradiofrequency ablation therapy (RFA) in patients with unresectable primary and secondary lung cancers.Methods: Institutional review board approval and informed consent were obtained. Twenty-three patients (13 men, 10women; age range, 28-81 years; mean age, 60 years) with 94 lung nodules (17 primary and 77 secondary lung neoplasms;mean diameter 1.6 cm, range 0.5-5 cm) were treated with an internally cooled electrode (13 patients with 29 nodules,20 sessions) and an expandable electrode (10 patients with 65 nodules, 50 sessions) from September 2005 to January2009. The overall tumor control rates were estimated using the Kaplan-Meier method. Comparisons of the tumor controlrates between the subgroups were performed using the log-rank test. P<0.05 was considered a significant defference.In addition,characteristics and ablation parameters, including tumor size, needle type, and primary or secondary lung neoplasms, were also analyzed with regard to local tumor progression.Results: The median follow-up period was 13.3 months (range, 3-33 months). The overall tumor control rates were 75% at１ year and 75% at 2 years. The tumor control rate was significantly higher in small (≤2 cm) than large (>2 cm) tumors (P =0.04). There was no significant difference in the tumor control rate between the internally cooled electrode method and theexpandable electrode method (P = 0.24). There was no significant difference in the tumor control rate between primaryand secondary lung neoplasms (P = 0.24). No procedural mortality occurred, and the overall major complication rate for 70sessions was 6% (pneumothorax requiring tube drainage in 2, pleural effusion requiring tube drainage in 1, and suspectedtumor seeding in 1). The rate of pneumothorax not requiring tube drainage (a minor complication) was 33% (23/70).Conclusion: RFA may be a feasible and minimally invasive option for unresectable lung cancers, with negligible mortalityand little morbidity in properly selected candidates