title: Local Excision Techniques for Rectal Cancer After Neoadjuvant Chemoradiotherapy: What Are We Doing?
abstract: BACKGROUND
  Recent evidence shows that the majority of rectal cancers demonstrate occult tumor scatter after neoadjuvant chemoradiotherapy that can extend for several centimeters under adjacent normal-appearing mucosa beside the residual mucosal abnormality or scar.
  
  
  OBJECTIVE
  This systematic review aimed to determine all of the published selection criteria and technical descriptions for local excision to date with regard to this phenomenon.
  
  
  METHODS
  PubMed, MEDLINE, and Embase were searched using the following key words: rectal cancer, local excision, radiotherapy, and neoadjuvant.
  
  
  METHODS
  Studies that assessed local excision of rectal cancer after neoadjuvant chemoradiotherapy were included. Duplicate series were excluded from final analysis.
  
  
  METHODS
  All of the data points were tabulated and analyzed using Microsoft Excel.
  
  
  METHODS
  Criteria for patient selection, surgical technique, clinical restaging, pathologic assessment, and indications for completion surgery were analyzed.
  
  
  RESULTS
  After exclusions, data from 25 studies that in total evaluated local excision in 1001 patients were included. Compared with the single accepted technique of total mesorectal excision, described techniques for local excision after neoadjuvant therapy demonstrate significant variability in many critical technical issues, such as marking/tattooing original tumor margins before neoadjuvant therapy, using pretreatment tumor size/stage as exclusion criteria, and specifically stating lateral excision margins. Where detailed, the majority of local recurrences occurred in patients with clear pathological margins, yet significant variation existed for pathological assessment and reporting, with few studies detailing R status and some not reporting margin status at all. Significant variability also existed for adverse tumor features that mandated completion surgery, and, importantly, many series describe patients refusing completion surgery where indicated.
  
  
  CONCLUSIONS
  We were unable to perform meta-analysis because studies lacked sufficient methodologic homogeneity to synthesize.
  
  
  CONCLUSIONS
  The observations from this study prompt additional study, standardization of technique, and cautious use of local excision of rectal cancer in the setting of neoadjuvant chemoradiotherapy.
authors.affiliation: 1 Department of Surgery, Royal Liverpool and Broadgreen University Hospitals National Health Service Trust, Liverpool, United Kingdom 2 Epsom and St Helier University Hospitals National Health Service Trust, London, United Kingdom 3 Angelita and Joaquim Gama Institute and School of Medicine, University of São Paulo, São Paulo, Brazil 4 Marks Colorectal Associates, Lankenau Hospital, Philadelphia, Pennsylvania, USA 5 Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology, Warsaw, Poland 6 Pelican Cancer Centre, Basingstoke, United Kingdom.
authors.forename: Fraser McLean
authors.initials: FM
authors.lastname: Smith
authors.forename: Abdul
authors.initials: A
authors.lastname: Ahad
authors.forename: Rodrigo Oliva
authors.initials: RO
authors.lastname: Perez
authors.forename: John
authors.initials: J
authors.lastname: Marks
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Bujko
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Heald
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D059248:Chemoradiotherapy; D013505:Digestive System Surgical Procedures / Q000379:methods*; D006801:Humans; D000072662:Margins of Excision; D008643:Mesentery / Q000601:surgery*; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000601:surgery*