title: Meta-analysis of the influence of surgical margin and adjuvant radiotherapy on local recurrence after resection of sporadic desmoid-type fibromatosis.
abstract: BACKGROUND
  Extra-abdominal desmoid-type fibromatosis (DF) is a rare, locally aggressive neoplasm that is usually managed conservatively. When treatment is indicated, it typically involves surgical resection, possibly with adjuvant radiotherapy. The indications for postoperative radiotherapy and its effectiveness are unclear. The objective of this study was to estimate the effect of surgical resection margins and adjuvant radiotherapy on rates of recurrence of DF.
  
  
  METHODS
  Literature published between 1999 and 2015 was extracted from MEDLINE, Embase, Cochrane Central Registry of Trials, Web of Science and Google Scholar. Recurrence rate was analysed by meta-analysis and compared between subgroups.
  
  
  RESULTS
  Sixteen reports were included, consisting of a total of 1295 patients with DF. In patients treated by surgical resection alone, the risk of local recurrence was almost twofold higher for those with microscopically positive resection margins (risk ratio (RR) 1·78, 95 per cent c.i. 1·40 to 2·26). Adjuvant radiotherapy after surgery with negative margins had no detectable benefit on recurrence. In contrast, after incomplete surgical resection, adjuvant radiotherapy improved recurrence rates both in patients with primary tumours (RR 1·54, 1·05 to 2·27) and in those with recurrent DF (RR 1·60, 1·12 to 2·28).
  
  
  CONCLUSIONS
  DF resected with microscopically positive margins has a higher risk of recurrence. Adjuvant radiotherapy appears to reduce the risk of recurrence after incomplete surgical resection, particularly in patients with recurrent tumours.
authors.affiliation: Departments of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: M L
authors.initials: ML
authors.lastname: Janssen
authors.affiliation: Departments of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: D L M
authors.initials: DL
authors.lastname: van Broekhoven
authors.affiliation: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Centre, Nashville, Tennessee, USA.
authors.forename: J M M
authors.initials: JM
authors.lastname: Cates
authors.affiliation: Departments of Medical Library, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands.
authors.forename: W M
authors.initials: WM
authors.lastname: Bramer
authors.affiliation: Departments of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: Nuyttens
authors.affiliation: Department of Soft Tissue/Bone Sarcoma and Melanoma, IRCCS Foundation National Cancer Institute, Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Gronchi
authors.affiliation: Department of Medical Oncology and Palliative Care, University of Aix Marseille, Marseille, France.
authors.forename: S
authors.initials: S
authors.lastname: Salas
authors.affiliation: Department of Surgery, Curie Institute, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Bonvalot
authors.affiliation: Departments of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: D J
authors.initials: DJ
authors.lastname: Grünhagen
authors.affiliation: Departments of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands.
authors.forename: C
authors.initials: C
authors.lastname: Verhoef
mesh_terms: D018221:Fibromatosis, Abdominal / Q000532:radiotherapy / Q000601:surgery*; D006801:Humans; D000072662:Margins of Excision; D009364:Neoplasm Recurrence, Local / Q000209:etiology; D018714:Radiotherapy, Adjuvant; D012307:Risk Factors; D016896:Treatment Outcome