title: Spot scanning proton therapy in the curative treatment of adult patients with sarcoma: the Paul Scherrer institute experience.
abstract: OBJECTIVE
  To assess the safety and efficacy of spot scanning proton beam therapy (PT) in the curative treatment of soft-tissue sarcoma (STS) in adults patients.
  
  
  METHODS
  We identified 13 STS patients treated with PT between July 1998 and May 2005 in our institutional database. Tumor histology varied with the most common histologic subtypes including liposarcoma and peripheral nerve sheet tumor. All tumors were located in vicinity of critical structures, such as the spinal cord, optic apparatus, bowel, kidney, or bowel. Of the patients, 6 and 5 patients received PT either as adjuvant therapy for non-R0 resection or for recurrence, respectively. Two patients received radical PT for unresectable disease. The median prescribed dose was 69.4 CGE (CGE = proton Gy x 1.1)-Gy (range, 50.4-76.0) at 1.8 to 2 CGE-Gy (median, 1.9) per fraction. Pre-PT anthracycline-based chemotherapy was delivered to 3 patients only. No patient has been lost to follow-up (median 48.1 months, range, 19.1-100.7 months).
  
  
  RESULTS
  Of the 13 patients, all but 2 patients were alive. Local recurrence developed in 3 (23%) patients. The administered dose to these patients was < or =60 Gy-CGE. Distant control was achieved in all but 2 patients (lung metastasis), 1 of whom presented with a concomitant local recurrence. The 4-year local control and metastasis-free survival rates were 74.1% and 84.6%, respectively. Late grade > or =2 toxicity was observed in only 2 patients.
  
  
  CONCLUSIONS
  Spot scanning PT is an effective and safe treatment for patient with STS in critical locations. The observed toxicity rate was acceptable.
authors.affiliation: Center for Proton Radiation Therapy, Paul Scherrer Institute, Villigen, Switzerland. damien.weber@hcuge.ch
authors.forename: Damien C
authors.initials: DC
authors.lastname: Weber
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Rutz
authors.forename: Alessandra
authors.initials: A
authors.lastname: Bolsi
authors.forename: Eros
authors.initials: E
authors.lastname: Pedroni
authors.forename: Adolf
authors.initials: A
authors.lastname: Coray
authors.forename: Martin
authors.initials: M
authors.lastname: Jermann
authors.forename: Antony J
authors.initials: AJ
authors.lastname: Lomax
authors.forename: Eugen B
authors.initials: EB
authors.lastname: Hug
authors.forename: Gudrun
authors.initials: G
authors.lastname: Goitein
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000532:radiotherapy*; D061766:Proton Therapy; D011522:Protons / Q000009:adverse effects; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects; D012509:Sarcoma / Q000532:radiotherapy*; D013557:Switzerland; D014057:Tomography, X-Ray Computed
chemical_list: D011522:Protons