title: Solitary plasmocytoma: improvement in critical organs sparing by means of helical tomotherapy.
abstract: OBJECTIVE
  Helical tomotherapy (HT) was assessed in two patients with paramedullar solitary bone plasmocytoma. We compared doses delivered to critical organs, according HT plan or tridimensional conformal plan.
  
  
  METHODS
  One male (patient no. 1), 67 yr-old and one female (patient no. 2), 37-yr-old, with histologically, biologically and radiological confirmed paramedullar solitary plasmocytoma have been treated in our department between November 2007 and February 2008 using HT. The prescription dose was 40 Gy in 20 fractions. This HT treatment planning was compared with a routine dosimetric work that was executed for a standard conformal radiotherapy treatment planning.
  
  
  RESULTS
  Treatment tolerance was excellent, without any side effects. Both patients achieved 9-month complete remission. HT resulted in substantial critical organs sparing. For patient no. 1, dose delivered to 20% of the total intestine volume was reduced from 28 Gy for conformal radiotherapy to 13 Gy for HT. Radiation dose delivered to 20% of the left kidney was reduced from 25 Gy to 7 Gy. For patient no. 2, volume of left lung that received at least 20 Gy was 12% for conformal radiotherapy vs. 6% for HT.
  
  
  CONCLUSIONS
  For paramedullar solitary plasmocytoma, HT has the potential to significantly improve the quality of the dose distribution both in terms of better dose homogeneity within the planning target volume and more efficient sparing of critical organs.
authors.affiliation: Department of Radiation Oncology, Institut Curie, Paris, France.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Chargari
authors.forename: Youlia M
authors.initials: YM
authors.lastname: Kirova
authors.forename: Sofia
authors.initials: S
authors.lastname: Zefkili
authors.forename: Lucas
authors.initials: L
authors.lastname: Caussa
authors.forename: Malika
authors.initials: M
authors.lastname: Amessis
authors.forename: Rémi
authors.initials: R
authors.lastname: Dendale
authors.forename: François
authors.initials: F
authors.lastname: Campana
authors.forename: Alain
authors.initials: A
authors.lastname: Fourquet
mesh_terms: D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D010954:Plasmacytoma / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012272:Ribs; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy; D036542:Tomography, Spiral Computed