title: Intensity modulated radiotherapy in abdominal malignancies: our experience in reducing the dose to normal structures as compared to the gross tumor.
abstract: OBJECTIVE
  A better understanding of appropriate sequencing and use of multimodality approach in the management and subsequent improvement in overall survival mandates a vigil on quality of life issues. Intensity modulated radiotherapy (IMRT) is a powerful tool, which might go a long way in reducing radiation doses to critical structures and thereby reduce long term morbidities. The purpose of this paper is to evaluate the impact of IMRT in reducing the dose to the critical normal tissues while maintaining the desired dose to the volume of interest for abdominal malignancies.
  
  
  METHODS
  During the period January 2002 to March 2004, 11 patients of various sites of malignancies in the abdominal region were treated using physical intensity modulator based IMRT. Plans of these patients treated with IMRT were analyzed using dose volume histograms.
  
  
  RESULTS
  An average dose reduction of the mean values by 50% to the liver, 57% to the right kidney, 56% to the left kidney, 66% to the cord and 27% to the bowel, with respect to the GTV could be achieved with IMRT. The two-year disease free survival was 79% and two-year overall survival was 88%. The average number of IMRT fields used was six.
  
  
  CONCLUSIONS
  IMRT with inverse planning enabled us to achieve desired dose distribution, due to its ability to provide sharp dose gradients at the junction of tumor and the adjacent critical organs.
authors.affiliation: Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi-110 085, India. t_kataria@rediffmail.com
authors.forename: Tejinder
authors.initials: T
authors.lastname: Kataria
authors.forename: Sheh
authors.initials: S
authors.lastname: Rawat
authors.forename: S N
authors.initials: SN
authors.lastname: Sinha
authors.forename: P S
authors.initials: PS
authors.lastname: Negi
authors.forename: Charu
authors.initials: C
authors.lastname: Garg
authors.forename: N K
authors.initials: NK
authors.lastname: Bhalla
authors.forename: R K
authors.initials: RK
authors.lastname: Munjal
mesh_terms: D000008:Abdominal Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome