title: Malignant triton tumors--complete surgical resection and adjuvant radiotherapy associated with improved survival.
abstract: BACKGROUND
  Malignant triton tumors (MTT) are a rare form of peripheral nerve sheath tumors that follows a particularly aggressive course. Given its rarity, only case reports and small series of patients have been published.
  
  
  METHODS
  A Pubmed search was conducted (1966-2009) using the terms "triton tumor," "rhabdomyosarcoma," and "malignant peripheral nerve sheath tumor." The reference lists of retrieved articles were searched. Cases were included when the diagnosis was clear, the patient underwent surgery, and follow-up data were available. Univariate and multivariate analyses were conducted for predictors of positive resection margin, local recurrence/progression, development of metastases, and mortality.
  
  
  RESULTS
  A total of 124 cases were included. The overall 5-year survival was 14% and the median time to death was 13 months. The overall local recurrence/progression rate was 50% and the median time to recurrence/progression was 6 months. On multivariate Cox proportional hazards analysis, positive margin status (HR 2.2, P = 0.01), local recurrence/progression (HR 3.1, P = 0.003), and development of metastases (HR 2.6, P = 0.003) were associated with mortality. Adjuvant radiotherapy was associated with improved survival (HR 0.4, P = 0.005).
  
  
  CONCLUSIONS
  Complete surgical resection and adjuvant radiotherapy should be the cornerstones of treatment for MTT.
authors.affiliation: Division of Surgical Oncology, Tom Baker Cancer Centre, University of Calgary, Calgary, Alberta, Canada. yarrow.mcconnell@albertahealthservices.ca
authors.forename: Yarrow J
authors.initials: YJ
authors.lastname: McConnell
authors.forename: Carman A
authors.initials: CA
authors.lastname: Giacomantonio
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D017024:Chemotherapy, Adjuvant; D016009:Chi-Square Distribution; D015986:Confounding Factors, Epidemiologic; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D018317:Nerve Sheath Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D009456:Neurofibromatosis 1 / Q000401:mortality / Q000628:therapy; D016016:Proportional Hazards Models; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome