title: CT-guided conformal cryoablation for peripheral NSCLC: initial experience.
abstract: OBJECTIVE
  To study the feasibility of CT-guided and monitored percutaneous conformal cryoablation of Non-Small Cell Lung Cancer for patients who are not suitable for surgical resection.
  
  
  METHODS
  CT-guided percutaneous conformal cryoablation was performed on 46 patients with peripheral Non-Small Cell Lung Cancer. Patients with tumor sizes less than 3 cm in diameter were treated with double-needle clamping cryoablation, while the patients with 3-5 cm tumor sizes were treated with multiple-needle conformal cryoablation. CT was used to monitor the extent of cryoablation during the procedures. At month 1, 3, 6, 12, and 24 post-procedure, enhanced CT scans and/or PET-CT scans were performed to evaluate the impact of the therapy.
  
  
  RESULTS
  The average tumor CT values were 32±10 HU and -21±8 HU before and after cryoablation, respectively. The largest diameters of the lesions at month 1, 3, 6, 12, and 24 post-procedure were 2.63±0.56 cm, 1.93±0.51 cm, 1.55±0.39 cm, 1.43±0.40 cm, and 1.38±0.38 cm, respectively, in patients with tumor diameter less than 3 cm, and 3.63±0.39 cm, 2.98±0.31 cm, 2.62±0.32 cm, 2.54±0.34 cm, and 2.56±0.37 cm respectively in patients with the tumor diameters between 3 and 5 cm. At the 24th month, there were 36 cases of complete response (83.7%), 7 cases of partial response (16.3%), and no cases of stable disease or progressive disease. 3 patients died due to multiple metastases.
  
  
  CONCLUSIONS
  CT-guided percutaneous conformal cryoablation is a safe, effective, and minimally invasive therapeutic method for peripheral lung cancer.
authors.affiliation: Department of Radiology, Chinese PLA General Hospital, Beijing 100853, China. Zhangxiao1732@sina.com.cn
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhang
authors.forename: Jinlin
authors.initials: J
authors.lastname: Tian
authors.forename: Lei
authors.initials: L
authors.lastname: Zhao
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Kacher
authors.forename: Xuyang
authors.initials: X
authors.lastname: Ma
authors.forename: Shurong
authors.initials: S
authors.lastname: Liu
authors.forename: Chao
authors.initials: C
authors.lastname: Ren
authors.forename: Yue-Yong
authors.initials: YY
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000601:surgery*; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011859:Radiography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome