title: Intraoperative Electron Radiation Therapy (IOERT) in the management of locally recurrent rectal cancer.
abstract: BACKGROUND
  To evaluate disease control, overall survival and prognostic factors in patients with locally recurrent rectal cancer after IOERT-containing multimodal therapy.
  
  
  METHODS
  Between 1991 and 2006, 97 patients with locally recurrent rectal cancer have been treated with surgery and IOERT. IOERT was preceded or followed by external beam radiation therapy (EBRT) in 54 previously untreated patients (median dose 41.4 Gy) usually combined with 5-Fluouracil-based chemotherapy (89%). IOERT was delivered via cylindric cones with doses of 10-20 Gy. Adjuvant CHT was given only in a minority of patients (34%). Median follow-up was 51 months.
  
  
  RESULTS
  Margin status was R0 in 37%, R1 in 33% and R2 in 30% of the patients. Neoadjuvant EBRT resulted in significantly increased rates of free margins (52% vs. 24%). Median overall survival was 39 months. Estimated 5-year rates for central control (inside the IOERT area), local control (inside the pelvis), distant control and overall survival were 54%, 41%, 40% and 30%. Resection margin was the strongest prognostic factor for overall survival (3-year OS of 80% (R0), 37% (R1), 35% (R2)) and LC (3-year LC 82% (R0), 41% (R1), 18% (R2)) in the multivariate model. OS was further significantly affected by clinical stage at first diagnosis and achievement of local control after treatment in the univariate model. Distant failures were found in 46 patients, predominantly in the lung. 90-day postoperative mortality was 3.1%.
  
  
  CONCLUSIONS
  Long term OS and LC can be achieved in a substantial proportion of patients with recurrent rectal cancer using a multimodality IOERT-containing approach, especially in case of clear margins. LC and OS remain limited in patients with incomplete resection. Preoperative re-irradiation and adjuvant chemotherapy may be considered to improve outcome.
authors.affiliation: Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany. F.Roeder@dkfz.de
authors.forename: Falk
authors.initials: F
authors.lastname: Roeder
authors.forename: Joerg-Michael
authors.initials: JM
authors.lastname: Goetz
authors.forename: Gregor
authors.initials: G
authors.lastname: Habl
authors.forename: Marc
authors.initials: M
authors.lastname: Bischof
authors.forename: Robert
authors.initials: R
authors.lastname: Krempien
authors.forename: Markus W
authors.initials: MW
authors.lastname: Buechler
authors.forename: Frank W
authors.initials: FW
authors.lastname: Hensley
authors.forename: Peter E
authors.initials: PE
authors.lastname: Huber
authors.forename: Juergen
authors.initials: J
authors.lastname: Weitz
authors.forename: Juergen
authors.initials: J
authors.lastname: Debus
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004583:Electrons / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000628:therapy*; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000379:methods; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology / Q000628:therapy*; D016019:Survival Analysis