title: Local recurrence after laparoscopic radiofrequency thermal ablation of hepatic tumors.
abstract: BACKGROUND
  Since we first described laparoscopic radiofrequency ablation (LRFA) of liver tumors, several reports have documented technical and safety aspects of this procedure. Little is known, however, about the long-term follow-up of such patients.
  
  
  METHODS
  From January 1996 to February 1999, we performed LRFA on 250 liver tumors in 66 patients. Triphasic spiral computed tomographic scanning was obtained preoperatively and at 1 week, and every 3 months postoperatively. Lesion diameter was measured in the x- and y-axes and the volume estimated; 181 lesions in 43 patients for whom computed tomographic scans available were included in the study. The tumor types were as follows: 64 metastatic adenocarcinomas, 79 neuroendocrine metastases, 27 other metastases, and 11 primary liver tumors.
  
  
  RESULTS
  One week postoperatively, the ablated zone was larger than the original tumor in 178 of 181 lesions, which suggests ablation of the tumor and a margin of normal liver tissue. A progressive decline in lesion size was seen in 156 (88%) of 178 lesions, followed for at least 3 months (mean, 13.9 months; range, 4.9-37.8 months), which suggests resorption of the ablated tissue. Fourteen definite local treatment failures were apparent by increase in size and change in computed tomographic scan appearance, and eight lesions were scored as failures because of multifocal recurrence that encroached on ablated foci (22 total recurrences). Predictors of failure include lack of increased lesion size at 1 week (2 of 3 such lesions failed), adenocarcinoma or sarcoma (18 of 22 failures; P < .05), larger tumors (failures, M = 18 cm3 vs. successes, M = 7 cm3; P < .005) and vascular invasion on laparoscopic ultrasonography. By size criteria, 17 of 22 failures were apparent by 6 months. Energy delivered per gram of tissue was not significantly different (P = .45).
  
  
  CONCLUSIONS
  LRFA has a 12% local failure rate, with larger adenocarcinomas and sarcomas at greatest risk. Failures occur early in follow-up, with most occurring by 6 months. LRFA seems to be a safe and effective treatment technique for patients with primary and metastatic liver malignancies.
authors.affiliation: Department of Surgery, University of California San Francisco, USA.
authors.forename: A
authors.initials: A
authors.lastname: Siperstein
authors.forename: A
authors.initials: A
authors.lastname: Garland
authors.forename: K
authors.initials: K
authors.lastname: Engle
authors.forename: S
authors.initials: S
authors.lastname: Rogers
authors.forename: E
authors.initials: E
authors.lastname: Berber
authors.forename: A
authors.initials: A
authors.lastname: Foroutani
authors.forename: A
authors.initials: A
authors.lastname: String
authors.forename: T
authors.initials: T
authors.lastname: Ryan
authors.forename: P
authors.initials: P
authors.lastname: Ituarte
mesh_terms: D000230:Adenocarcinoma / Q000601:surgery; D006528:Carcinoma, Hepatocellular / Q000601:surgery; D018278:Carcinoma, Neuroendocrine / Q000000981:diagnostic imaging / Q000601:surgery; D017115:Catheter Ablation; D005500:Follow-Up Studies; D006801:Humans; D010535:Laparoscopy; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D011788:Quality of Life; D014057:Tomography, X-Ray Computed; D017211:Treatment Failure