title: Long-Term Survival after Radiofrequency Ablation of Lung Oligometastases from Five Types of Primary Lesions: A Retrospective Evaluation.
abstract: OBJECTIVE
  To conduct a retrospective evaluation of long-term survival after radiofrequency (RF) ablation for lung oligometastases from 5 types of primary lesions.
  
  
  METHODS
  The study population consisted of 123 patients with lung oligometastases from colorectal cancer (CRC), non-small-cell lung cancer, hepatocellular carcinoma, esophageal cancer, and renal-cell carcinoma treated with RF ablation. Lung oligometastases were defined as 1-5 metastases confined to the lung while the primary cancer and other metastases were eradicated. Overall survival (OS) and recurrence-free survival (RFS) were estimated for the overall study population and for patients with each type of primary lesion. The OS and RFS rates were compared with those of the patients with any of the other four primary lesion types. Finally, various variables were analyzed to determine what factors influenced OS and RFS.
  
  
  RESULTS
  The median follow-up was 45.7 months, and the 5-year OS and RFS rates for all 123 patients were 62% and 25%, respectively. The OS time for patients with metastases from CRC was significantly longer (P = .042); it was significantly shorter (P = .022) in patients with metastases from esophageal cancer. Longer disease-free interval was significantly (P = .015) associated with better OS. There was no variable significantly associated with OS and RFS on multivariate analyses.
  
  
  CONCLUSIONS
  Data from this single-center study appear promising in terms of long-term survival after RF ablation of lung oligometastases from 5 primary lesions.
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Omae
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan. Electronic address: takaoh@tc4.so-net.ne.jp.
authors.forename: Takao
authors.initials: T
authors.lastname: Hiraki
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Gobara
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Iguchi
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Fujiwara
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Matsui
authors.affiliation: Department of General Thoracic Surgery, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Toyooka
authors.affiliation: Department of Gastroenterological Surgery, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nagasaka
authors.affiliation: Department of Radiology, Okayama University Medical School, 2-5-1 Shikatacho, Kita-ku, Okayama 700-8558, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Kanazawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000009:adverse effects / Q000401:mortality; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D017741:Survivors; D013997:Time Factors; D016896:Treatment Outcome