title: Analysis of local recurrences after transanal endoscopic microsurgery for low risk rectal carcinoma.
abstract: OBJECTIVE
  Rates of local recurrence (LR) after transanal endoscopic microsurgery (TEM) for rectal carcinoma vary; the reasons remain unclear. We analyzed LR after TEM for low-risk pT1 (G1/2/X, L0/X) rectal carcinoma to investigate the influence of completeness of resection and occult lymph node metastasis on risk of LR.
  
  
  METHODS
  LR location and stage, completeness of resection of primary carcinoma (minimal distance between tumor and resection line ≤1 mm vs >1 mm), and incidence of involved lymph nodes in resected LR specimens were collected, and tumor characteristics of LR were compared with primary carcinoma. Distant metastasis and overall and cancer-specific survival were determined.
  
  
  RESULTS
  LR developed in 14 patients; in 2/4 with R1/X resection, in 3/8 (38%) with clear margins (R0) but a minimal distance of ≤1 mm, and in 9/88 (10%) with formally complete resection. Six of nine patients with formally complete resection underwent radical surgery for LR; in five out of these six, lymph nodes were not involved. In 5/14 patients, LR was poorly differentiated compared to primary carcinoma. Main LR causes were incomplete tumor resection or tumor persistence after formally complete resection. Overall (p = 0.008) and cancer-specific (p < 0.001) survival was lower in LR patients compared to non-LR patients, even if lymph nodes were uninvolved.
  
  
  CONCLUSIONS
  The results suggest that most LRs after TEM for low-risk rectal cancer were caused by residual tumor at the previous excision site and not by undetected lymph node metastases. By improved standardization of surgical techniques to ensure complete resection of carcinomas and thorough pathological assessments, most LRs seem to be avoidable.
authors.affiliation: Department of General and Abdominal Surgery, University Medical Centre of the Johannes Gutenberg-University, Langenbeckstr. 1, 55131, Mainz, Germany. Junginger@uni-mainz.de.
authors.forename: Theodor
authors.initials: T
authors.lastname: Junginger
authors.affiliation: Department of General and Abdominal Surgery, University Medical Centre of the Johannes Gutenberg-University, Langenbeckstr. 1, 55131, Mainz, Germany.
authors.forename: Ursula
authors.initials: U
authors.lastname: Goenner
authors.affiliation: Department of General, Visceral and Vascular Surgery, Catholic Hospital Mainz, Mainz, Germany.
authors.forename: Mirjam
authors.initials: M
authors.lastname: Hitzler
authors.affiliation: Department of Heart, Chest and Vascular Surgery, University Medical Centre of the Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Tong T
authors.initials: TT
authors.lastname: Trinh
authors.affiliation: Department of General, Visceral and Vascular Surgery, Catholic Hospital Mainz, Mainz, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Heintz
authors.affiliation: Institute of Pathology, University Medical Centre of the Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Roth
authors.affiliation: Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Centre of the Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Blettner
authors.affiliation: Institute of Medical Biostatistics, Epidemiology and Informatics, University Medical Centre of the Johannes Gutenberg-University, Mainz, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wollschlaeger
mesh_terms: D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D012307:Risk Factors; D000067369:Transanal Endoscopic Microsurgery
keywords: Causes of local recurrence; Local recurrence; Low-risk rectal carcinoma; Transanal endoscopic microsurgery