title: Recurrence after microwave ablation of liver malignancies: a single institution experience.
abstract: BACKGROUND
  Microwave ablation (MWA) is increasingly used to achieve local control for liver tumours. This study sought to examine a monocentric experience with MWA, with a primary hypothesis that primary tumour histology was a significant predictor of early recurrence.
  
  
  METHODS
  Retrospective single-institution review identified consecutive patients with liver tumours treated by MWA. Cox proportional hazards models assessed significance of prognostic variables.
  
  
  RESULTS
  Seventy-two patients (43 female, 60%) underwent 83 MWA procedures for 157 tumours. Tumour histologies included hepatocellular cancer (10 operations), colorectal metastases (39), metastatic carcinoid (20) and other (14). The median tumour size was 2.0 cm. A concomitant liver resection was performed in 50 cases (60%). Crude peri-operative morbidity and mortality rates were 16% and 1%, respectively. The median follow-up was 16 months. Ablations were complete for 149 out of 157 tumours (95%). The median overall and recurrence-free survivals were 36 and 18 months, respectively. There was no difference in time to recurrence between the primary tumour types. In multivariable models, recurrence-free survival was independently associated with the use of neoadjuvant [hazard ratio (HR): 2.90, 95% confidence interval (CI): 1.09-7.76, P = 0.034] and adjuvant chemotherapy (HR: 0.36, 95% CI: 0.15-0.82, P = 0.016).
  
  
  CONCLUSIONS
  MWA is a safe and feasible approach for local control of liver tumours. While chemotherapy administration was associated with time to recurrence after MWA, larger studies are needed to corroborate these findings.
authors: Division of Surgical Oncology, Department of Surgery, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Ryan T
authors: RT
authors: Groeschl
authors: Ray K
authors: RK
authors: Wong
authors: Edward J
authors: EJ
authors: Quebbeman
authors: Susan
authors: S
authors: Tsai
authors: Kiran K
authors: KK
authors: Turaga
authors: Sam G
authors: SG
authors: Pappas
authors: Kathleen K
authors: KK
authors: Christians
authors: Eric J
authors: EJ
authors: Hohenwalter
authors: Sean M
authors: SM
authors: Tutton
authors: William S
authors: WS
authors: Rilling
authors: T Clark
authors: TC
authors: Gamblin
mesh_terms: D055011:Ablation Techniques; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008872:Microwaves / Q000627:therapeutic use; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology* / Q000473:pathology; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome