title: Percutaneous microwave ablation of hepatic tumors: prospective evaluation of postablation syndrome and postprocedural pain.
abstract: OBJECTIVE
  To prospectively investigate the frequency and severity of postablation syndrome (PAS) and postprocedural pain in a cohort of patients undergoing hepatic microwave ablation.
  
  
  METHODS
  From March 2009 to November 2011, 54 consecutive patients undergoing microwave ablation for liver tumors were enrolled. A questionnaire was administered to investigate PAS and pain at 1, 7, and 40 days after ablation. Four patients did not complete all three questionnaires and were excluded from the analysis. Additionally, laboratory tests with results known to significantly increase or decrease after ablation were performed, and ablation parameters were recorded. Potential predictors of PAS and pain at 1 and 7 days were evaluated by a logistic regression model.
  
  
  RESULTS
  Fifty patients underwent a single microwave ablation session, 33 for hepatocellular carcinoma (HCC) and 17 for liver metastasis. Median ablation volumes on computed tomography were 31 cm(3) for HCC and 42 cm(3) for metastasis. Sixty percent of patients experienced PAS in the first week. Aspartate aminotransferase (AST) levels after ablation were significantly associated with PAS during postprocedure days 1-7. Median visual analog scale scores for pain at the puncture site were 1 and 0.24 at 1 and 7 days, respectively. The risk of having at least moderate pain in the first week was significantly related to ablation volume and time and postablation increase in AST level.
  
  
  CONCLUSIONS
  The incidence and severity of PAS with hepatic microwave ablation is similar to that reported for radiofrequency ablation, with the best predictive factor being postablation AST level elevation. Postablation pain was best predicted by total ablation volume and AST level.
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Monza; Centre of Biostatistics for Clinical Epidemiology, University of Milano-Bicocca, Monza.
authors.forename: Anita
authors.initials: A
authors.lastname: Andreano
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Monza; Centre of Biostatistics for Clinical Epidemiology, University of Milano-Bicocca, Monza.
authors.forename: Stefania
authors.initials: S
authors.lastname: Galimberti
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Monza.
authors.forename: Elvira
authors.initials: E
authors.lastname: Franza
authors.affiliation: Department of Radiology, University of Wisconsin, Madison, Wisconsin.
authors.forename: Erica M
authors.initials: EM
authors.lastname: Knavel
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Monza.
authors.forename: Sandro
authors.initials: S
authors.lastname: Sironi
authors.affiliation: Department of Radiology, University of Wisconsin, Madison, Wisconsin.
authors.forename: Fred T
authors.initials: FT
authors.lastname: Lee
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Monza; Department of Radiology, Ospedale Valduce, via Dante 11, Como 22100, Italy. Electronic address: meloni.mariafranca@gmail.com.
authors.forename: Maria Franca
authors.initials: MF
authors.lastname: Meloni
mesh_terms: D055011:Ablation Techniques / Q000009:adverse effects*; D000368:Aged; D001219:Aspartate Aminotransferases / Q000097:blood; D015415:Biomarkers / Q000097:blood; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary / Q000601:surgery*; D016015:Logistic Models; D008297:Male; D008872:Microwaves / Q000009:adverse effects*; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010147:Pain Measurement; D010149:Postoperative Pain / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013577:Syndrome; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D001219:Aspartate Aminotransferases
keywords: ALT; AST; ECOG; Eastern Cooperative Oncology Group; HCC; IQR; OR; PAS; PS; RF; SD; VAS; alanine aminotransferase; aspartate aminotransferase; hepatocellular carcinoma; i.v.; interquartile range; intravenous; odds ratio; performance status; postablation syndrome; radiofrequency; standard deviation; visual analog scale