title: Intensity-modulated radiotherapy results in significant decrease in clinical toxicities compared with conventional wedge-based breast radiotherapy.
abstract: OBJECTIVE
  We have previously demonstrated that intensity-modulated radiotherapy (IMRT) with a static multileaf collimator process results in a more homogenous dose distribution compared with conventional wedge-based whole breast irradiation (WBI). In the present analysis, we reviewed the acute and chronic toxicity of this IMRT approach compared with conventional wedge-based treatment.
  
  
  METHODS
  A total of 172 patients with Stage 0-IIB breast cancer were treated with lumpectomy followed by WBI. All patients underwent treatment planning computed tomography and received WBI (median dose, 45 Gy) followed by a boost to 61 Gy. Of the 172 patients, 93 (54%) were treated with IMRT, and the 79 patients (46%) treated with wedge-based RT in a consecutive fashion immediately before this cohort served as the control group. The median follow-up was 4.7 years.
  
  
  RESULTS
  A significant reduction in acute Grade 2 or worse dermatitis, edema, and hyperpigmentation was seen with IMRT compared with wedges. A trend was found toward reduced acute Grade 3 or greater dermatitis (6% vs. 1%, p = 0.09) in favor of IMRT. Chronic Grade 2 or worse breast edema was significantly reduced with IMRT compared with conventional wedges. No difference was found in cosmesis scores between the two groups. In patients with larger breasts (> or =1,600 cm(3), n = 64), IMRT resulted in reduced acute (Grade 2 or greater) breast edema (0% vs. 36%, p <0.001) and hyperpigmentation (3% vs. 41%, p = 0.001) and chronic (Grade 2 or greater) long-term edema (3% vs. 30%, p = 0.007).
  
  
  CONCLUSIONS
  The use of IMRT in the treatment of the whole breast results in a significant decrease in acute dermatitis, edema, and hyperpigmentation and a reduction in the development of chronic breast edema compared with conventional wedge-based RT.
authors.affiliation: Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48073, USA.
authors.forename: Asif
authors.initials: A
authors.lastname: Harsolia
authors.forename: Larry
authors.initials: L
authors.lastname: Kestin
authors.forename: Inga
authors.initials: I
authors.lastname: Grills
authors.forename: Michelle
authors.initials: M
authors.lastname: Wallace
authors.forename: Shruti
authors.initials: S
authors.lastname: Jolly
authors.forename: Cortney
authors.initials: C
authors.lastname: Jones
authors.forename: Moinaktar
authors.initials: M
authors.lastname: Lala
authors.forename: Alvaro
authors.initials: A
authors.lastname: Martinez
authors.forename: Scott
authors.initials: S
authors.lastname: Schell
authors.forename: Frank A
authors.initials: FA
authors.lastname: Vicini
mesh_terms: D000208:Acute Disease; D001940:Breast / Q000473:pathology; D001941:Breast Diseases / Q000209:etiology; D001943:Breast Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D016022:Case-Control Studies; D002908:Chronic Disease; D004487:Edema / Q000209:etiology; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000209:etiology; D015412:Mastectomy, Segmental; D008875:Middle Aged; D011832:Radiation Injuries / Q000209:etiology*; D011855:Radiodermatitis / Q000209:etiology; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects*