title: Radiation therapy for aggressive fibromatosis (desmoid tumors): results of a national Patterns of Care Study.
abstract: OBJECTIVE
  After a general Patterns of Care Study (PCS) the German Cooperative Group on Radiotherapy for Benign Diseases (GCG-BD) initiated a multicenter cohort study to analyze the radiation therapy practice for aggressive fibromatosis.
  
  
  METHODS
  In 2002 a PCS was conducted in all German radiotherapy (RT) institutions by mailing a standardized structured questionnaire, to assess patients accrual, number, pretreatment, treatment indications, RT, and target volume concepts for irradiation in aggressive fibromatosis. In addition, the treatment outcome of individual patients was evaluated. The PCS was structured and analyzed according to the model for quality assessment by Donabedian in three major components: structure, process, and outcome evaluation.
  
  
  RESULTS
  A total of 101 institutions returned the questionnaire: 52.7% reported satisfactory clinical data and experience for inclusion in this analysis. A total accrual rate of 278 patients per year was reported with median number of 2 cases (1-7 cases) per institution. Satisfactory data for a long-term clinical evaluation was reported for 345 patients from 19 different institutions. The applied total doses ranged between 36 and 65 Gy (median, 60 Gy). The local control rate was 81.4% in primary RT for unresectable tumors and 79.6% in postoperative RT. No acute or late radiation toxicities > Grade 2 (RTOG) were observed. No clear dose-response relationship could be established, but there was a tendency toward a lower local control rate in patients with a higher number of operative procedures before RT and patients treated for recurrent aggressive fibromatosis.
  
  
  CONCLUSIONS
  This study comprises the largest database of cases reported for RT in aggressive fibromatosis. Radiotherapy provides a high local control rate in the postoperative setting and in unresectable tumors. This PCS may serve as a starting point for a national or international prospective multicenter study or registry, or both.
authors.affiliation: Department of Radiotherapy, Münster University Hospital, Albert-Schweitzer-Strasse 33, 48129 Münster, Germany. omicke@benign-news.de
authors.forename: Oliver
authors.initials: O
authors.lastname: Micke
authors.forename: M Heinrich
authors.initials: MH
authors.lastname: Seegenschmiedt
mesh_terms: D005260:Female; D018222:Desmoid Tumors / Q000532:radiotherapy*; D005858:Germany; D019538:Health Care Surveys; D006801:Humans; D008297:Male; D011879:Radiotherapy Dosage; D013223:Statistics as Topic; D011795:Surveys and Questionnaires; D016896:Treatment Outcome