title: Stereotactic body radiation therapy for abdominal targets using volumetric intensity modulated arc therapy with RapidArc: feasibility and clinical preliminary results.
abstract: OBJECTIVE
  To report early clinical experience in stereotactic body radiation therapy (SBRT) delivered using volumetric intensity modulated arc therapy with RapidArc (RA) in patients with primary or metastatic tumours at abdominal sites.
  
  
  METHODS
  Thirty-seven consecutive patients were treated using RA. Of these, 16 had primary or metastatic liver tumours, nine had pancreatic cancer and 12 a nodal metastasis in the retro-peritoneum. Dose prescription varied from 45 to 75 Gy to the Clinical Target Volume in 3 to 6 fractions. The median follow-up was 12 months (6-22). Early local control and toxicity were investigated and reported.
  
  
  RESULTS
  Planning objectives on target volumes and organs at risk were met in most cases. Delivery time ranged from 2.8 ± 0.3 to 9.2 ± 2.4 minutes and pre-treatment plan verification resulted in a Gamma Agreement Index from 95.3 ± 3.8 to 98.3 ± 1.7%. At the time of analysis, local control (freedom from progression) at six months, was assessable in 24 of 37 patients and was achieved in 19 patients with a crude rate of 79.2%. Seven patients experienced treatment-related toxicity. Three patients experienced a mild and transient G1 enteritis and two showed a transient G1 liver damage. Two had late toxicity: one developed chronic enteritis causing G1 diarrhoea and G1 abdominal pain and one suffered at three months a G3 gastric bleeding. No patients experienced G4 acute toxicity.
  
  
  CONCLUSIONS
  SBRT for abdominal targets delivered by means of RA resulted to be feasible with good early clinical results in terms of local control rate and acute toxicity profile. RA allowed to achieve required target coverage as well as to keep within normal tissue dose/volume constraints.
authors.affiliation: IRCCS Istituto Clinico Humanitas, Rozzano (Milano), Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Scorsetti
authors.forename: Mario
authors.initials: M
authors.lastname: Bignardi
authors.forename: Filippo
authors.initials: F
authors.lastname: Alongi
authors.forename: Antonella
authors.initials: A
authors.lastname: Fogliata
authors.forename: Pietro
authors.initials: P
authors.lastname: Mancosu
authors.forename: Piera
authors.initials: P
authors.lastname: Navarria
authors.forename: Simona
authors.initials: S
authors.lastname: Castiglioni
authors.forename: Sara
authors.initials: S
authors.lastname: Pentimalli
authors.forename: Angelo
authors.initials: A
authors.lastname: Tozzi
authors.forename: Luca
authors.initials: L
authors.lastname: Cozzi
mesh_terms: D000005:Abdomen / Q000528:radiation effects*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000532:radiotherapy*; D011379:Prognosis; D016634:Radiosurgery; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D015996:Survival Rate