title: Phase I-II study of hypofractionated simultaneous integrated boost using volumetric modulated arc therapy for adjuvant radiation therapy in breast cancer patients: a report of feasibility and early toxicity results in the first 50 treatments.
abstract: BACKGROUND
  To report results in terms of feasibility and early toxicity of hypofractionated simultaneous integrated boost (SIB) approach with Volumetric Modulated Arc Therapy (VMAT) as adjuvant treatment after breast-conserving surgery.
  
  
  METHODS
  Between September 2010 and May 2011, 50 consecutive patients presenting early-stage breast cancer were submitted to adjuvant radiotherapy with SIB-VMAT approach using RapidArc in our Institution (Istituto Clinico Humanitas ICH). Three out of 50 patients were irradiated bilaterally (53 tumours in 50 patients). All patients were enrolled in a phase I-II trial approved by the ICH ethical committee. All 50 patients enrolled in the study underwent VMAT-SIB technique to irradiate the whole breast with concomitant boost irradiation of the tumor bed. Doses to whole breast and surgical bed were 40.5 Gy and 48 Gy respectively, delivered in 15 fractions over 3 weeks. Skin toxicities were recorded during and after treatment according to RTOG acute radiation morbidity scoring criteria with a median follow-up of 12 months (range 8-16). Cosmetic outcomes were assessed as excellent/good or fair/poor.
  
  
  RESULTS
  The median age of the population was 68 years (range 36-88). According to AJCC staging system, 38 breast lesions were classified as pT1, and 15 as pT2; 49 cases were assessed as N0 and 4 as N1. The maximum acute skin toxicity by the end of treatment was Grade 0 in 20/50 patients, Grade 1 in 32/50, Grade 2 in 0 and Grade 3 in 1/50 (one of the 3 cases of bilateral breast irradiation). No Grade 4 toxicities were observed. All Grade 1 toxicities had resolved within 3 weeks. No significant differences in cosmetic scores on baseline assessment vs. 3 months and 6 months after the treatment were observed: all patients were scored as excellent/good (50/50) compared with baseline; no fair/poor judgment was recorded. No other toxicities or local failures were recorded during follow-up.
  
  
  CONCLUSIONS
  The 3-week course of postoperative radiation using VMAT with SIB showed to be feasible and was associated with acceptable acute skin toxicity profile. Long-term follow-up data are needed to assess late toxicity and clinical outcomes.
authors.affiliation: Radiotherapy and radiosurgery, Humanitas Cancer Center, Istituto Clinico Humanitas, Rozzano, Milano, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Scorsetti
authors.forename: Filippo
authors.initials: F
authors.lastname: Alongi
authors.forename: Antonella
authors.initials: A
authors.lastname: Fogliata
authors.forename: Sara
authors.initials: S
authors.lastname: Pentimalli
authors.forename: Pierina
authors.initials: P
authors.lastname: Navarria
authors.forename: Francesca
authors.initials: F
authors.lastname: Lobefalo
authors.forename: Carlos
authors.initials: C
authors.lastname: Garcia-Etienne
authors.forename: Alessandro
authors.initials: A
authors.lastname: Clivio
authors.forename: Luca
authors.initials: L
authors.lastname: Cozzi
authors.forename: Pietro
authors.initials: P
authors.lastname: Mancosu
authors.forename: Giorgia
authors.initials: G
authors.lastname: Nicolini
authors.forename: Eugenio
authors.initials: E
authors.lastname: Vanetti
authors.forename: Marco
authors.initials: M
authors.lastname: Eboli
authors.forename: Carlo
authors.initials: C
authors.lastname: Rossetti
authors.forename: Arianna
authors.initials: A
authors.lastname: Rubino
authors.forename: Andrea
authors.initials: A
authors.lastname: Sagona
authors.forename: Stefano
authors.initials: S
authors.lastname: Arcangeli
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gatzemeier
authors.forename: Giovanna
authors.initials: G
authors.lastname: Masci
authors.forename: Rosalba
authors.initials: R
authors.lastname: Torrisi
authors.forename: Alberto
authors.initials: A
authors.lastname: Testori
authors.forename: Marco
authors.initials: M
authors.lastname: Alloisio
authors.forename: Armando
authors.initials: A
authors.lastname: Santoro
authors.forename: Corrado
authors.initials: C
authors.lastname: Tinterri
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology / Q000532:radiotherapy*; D018275:Carcinoma, Lobular / Q000473:pathology / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D011832:Radiation Injuries / Q000209:etiology*; D018714:Radiotherapy, Adjuvant; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*