title: Analysis by MRI of residual tumor after radiofrequency ablation for early stage breast cancer.
abstract: OBJECTIVE
  The objective of our study was to evaluate the effectiveness of MRI in the detection of possible residual lesions after radiofrequency ablation (RFA) in the treatment of breast cancer.
  
  
  METHODS
  We prospectively evaluated 14 patients who had undergone ultrasound-guided core biopsies diagnostic of invasive ductal carcinoma (IDC; range of diameters, 1.0-3.0 cm) and then ultrasound-guided percutaneous RFA with sentinel node biopsy as the primary treatment. Breast MRI was performed 1 week before RFA to evaluate tumor extension and again 3 weeks after RFA to verify the presence of possible residual lesions. Conventional surgical resection of the tumors was performed 1 week after RFA. The MRI findings were compared with histopathologic analyses to confirm the presence or absence of residual tumor.
  
  
  RESULTS
  There was no residual enhancement in seven lesions on the postablation breast MRI scans. These findings were confirmed by negative histopathologic findings in the surgical specimens. The MRI scans of five patients showed small areas of irregular enhancement that corresponded to residual lesions. In the two remaining patients, we observed enhancement of almost the entire lesion, indicating that RFA had failed.
  
  
  CONCLUSIONS
  Breast MRI is effective in detecting residual lesions after RFA in patients with IDC.
authors.affiliation: Department of Diagnostic Imaging, Federal University of Sao Paulo, Rua Napoleão de Barros, 800, Vila Clementino, Sao Paulo 04024-000, Brazil. vanvilar76@gmail.com
authors.forename: Vanessa Sales
authors.initials: VS
authors.lastname: Vilar
authors.forename: Suzan Menasce
authors.initials: SM
authors.lastname: Goldman
authors.forename: Marcos Desidério
authors.initials: MD
authors.lastname: Ricci
authors.forename: Katia
authors.initials: K
authors.lastname: Pincerato
authors.forename: Helio
authors.initials: H
authors.lastname: Oliveira
authors.forename: Thiago Giansante
authors.initials: TG
authors.lastname: Abud
authors.forename: Sergio
authors.initials: S
authors.lastname: Ajzen
authors.forename: Edmund Chada
authors.initials: EC
authors.lastname: Baracat
authors.forename: Jacob
authors.initials: J
authors.lastname: Szejnfeld
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology* / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods*; D003287:Contrast Media; D004566:Electrodes; D004867:Equipment Design; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008536:Meglumine; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000473:pathology*; D009942:Organometallic Compounds; D011446:Prospective Studies; D021701:Sentinel Lymph Node Biopsy; D018084:Ultrasonography, Interventional
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D008536:Meglumine; C072417:gadoterate meglumine