title: Use of tomotherapy in treatment of synchronous bilateral breast cancer: dosimetric comparison study.
abstract: OBJECTIVE
  Synchronous malignancy in both breasts is a rare incidence. The present study aims at dosimetric comparison of conventional bitangential radiotherapy (RT) technique with conventional [field-in-field (FIF)] and rotational [Helical TomoTherapy(®) and TomoDirect™ (TD); Accuray Inc., Sunnyvale, CA] intensity-modulated RT for patients with synchronous bilateral breast cancer (SBBC).
  
  
  METHODS
  CT data sets of 10 patients with SBBC were selected for the present study. RT was planned for all patients on both sides to whole breast and/or chest wall using the above-mentioned techniques. Six females with breast conservation on at least one side also had a composite plan along with tumour bed (TB) boost using sequential electrons for bitangential and FIF techniques or sequential helical tomotherapy (HT) boost (for TD) or simultaneous integrated boost (SIB) for HT.
  
  
  RESULTS
  All techniques produced acceptable target coverage. The hotspot was significantly lower with FIF technique and HT but higher with TD. For the organs at risk doses, HT resulted in significant reduction of the higher dose volumes. Similarly, TD resulted in significant reduction of the mean dose to the heart and total lung by reducing the lower dose volumes. All techniques of delivering boost to the TB were comparable in terms of target coverage. HT-SIB markedly reduced mean doses to the total lung and heart by specifically lowering the higher dose volumes.
  
  
  CONCLUSIONS
  This study demonstrates the cardiac and pulmonary sparing ability of tomotherapy in the setting of SBBC.
  
  
  CONCLUSIONS
  This is the first study demonstrating feasibility of treatment of SBBC using tomotherapy.
authors.affiliation: 1 Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: T
authors.initials: T
authors.lastname: Wadasadawala
authors.forename: B
authors.initials: B
authors.lastname: Visariya
authors.forename: R
authors.initials: R
authors.lastname: Sarin
authors.forename: R R
authors.initials: RR
authors.lastname: Upreti
authors.forename: S
authors.initials: S
authors.lastname: Paul
authors.forename: R
authors.initials: R
authors.lastname: Phurailatpam
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D009378:Neoplasms, Multiple Primary / Q000473:pathology / Q000532:radiotherapy*; D058958:Organs at Risk; D010865:Pilot Projects; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D016896:Treatment Outcome