title: Superficial myxofibrosarcoma: assessment of recurrence risk according to the surgical margin following resection. A series of 21 patients.
abstract: BACKGROUND
  Superficial myxofibrosarcomas are malignant connective tissue tumors, whose very frequent recurrence influences the local and vital prognosis. Even when resection seems to be macroscopically complete it is very often microscopically contaminated. The aim of this study was to evaluate recurrence in relation to the surgical margins and to compare, when possible, tumor size, evaluated clinically and macroscopically by the pathologist.
  
  
  METHODS
  This was a single center study of 21 patients, mean age 67 years old, treated for superficial myxofibrosarcoma. The number, date and location of recurrence were collected for each patient. A clinical and pathological measurement was made of the longest axis of the tumor in each case of recurrence.
  
  
  RESULTS
  Fifty-seven percent of patients presented with recurrent tumors. The mean number of recurrences was 1.4 per patient (1-8). The surgical margins were wide in four cases, marginal in two cases and incomplete/intralesional in 15 other patients with a rate of recurrence of 25, 50 and 67% respectively. The size evaluated during the preoperative clinical examination (14 cases) was underestimated by a mean 2.4 cm compared to the macroscopic pathology assessment. The preoperative size on MRI (5 cases) was also underestimated by a mean 1.3 cm.
  
  
  CONCLUSIONS
  Superficial myxofibrosarcomas are tumors that are difficult to resect completely because they are infiltrative, a feature that is often underestimated before surgery. Surgical treatment of this entity requires a much larger surgical margin than that suggested by the preoperative clinical and MRI evaluations. In case of incomplete resection, revision scar surgery should systematically be performed.
  
  
  METHODS
  Level IV. Retrospective study.
authors.affiliation: Department of Orthopaedic oncologic Surgery, Descartes Sorbonne Paris University, Cochin Hospital, Paris Public Assistance Hospital Group, Paris Cité, 27, rue du Faubourg-Saint-Jacques, 75014 Paris, France. g.riouallon@gmail.com
authors.forename: G
authors.initials: G
authors.lastname: Riouallon
authors.forename: F
authors.initials: F
authors.lastname: Larousserie
authors.forename: E
authors.initials: E
authors.lastname: Pluot
authors.forename: P
authors.initials: P
authors.lastname: Anract
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018223:Dermatofibrosarcoma / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis / Q000453:epidemiology*; D012189:Retrospective Studies