title: Intensity modulated radiotherapy in early stage Hodgkin lymphoma patients: is it better than three dimensional conformal radiotherapy?
abstract: BACKGROUND
  Cure rate of early Hodgkin Lymphoma are high and avoidance of late toxicities is of paramount importance. This comparative study aims to assess the normal tissue sparing capability of intensity-modulated radiation therapy (IMRT) versus standard three-dimensional conformal radiotherapy (3D-CRT) in terms of dose-volume parameters and normal tissue complication probability (NTCP) for different organs at risk in supradiaphragmatic Hodgkin Lymphoma (HL) patients.
  
  
  METHODS
  Ten HL patients were actually treated with 3D-CRT and all treatments were then re-planned with IMRT. Dose-volume parameters for thyroid, oesophagus, heart, coronary arteries, lung, spinal cord and breast were evaluated. Dose-volume histograms generated by TPS were analyzed to predict the NTCP for the considered organs at risk, according to different endpoints.
  
  
  RESULTS
  Regarding dose-volume parameters no statistically significant differences were recorded for heart and origin of coronary arteries. We recorded statistically significant lower V30 with IMRT for oesophagus (6.42 vs 0.33, p = 0.02) and lungs (4.7 vs 0.1 p = 0.014 for the left lung and 2.59 vs 0.1 p = 0.017 for the right lung) and lower V20 for spinal cord (17.8 vs 7.2 p = 0.02). Moreover the maximum dose to the spinal cord was lower with IMRT (30.2 vs 19.9, p <0.001). Higher V10 with IMRT for thyroid (64.8 vs 95, p = 0.0019) and V5 for lungs (30.3 vs 44.8, p = 0.03, for right lung and 28.9 vs 48.1, p = 0.001 for left lung) were found, respectively. Higher V5 and V10 for breasts were found with IMRT (V5: 4.14 vs 20.6, p = 0.018 for left breast and 3.3 vs 17, p = 0.059 for right breast; V10: 2.5 vs 13.6 p = 0.035 for left breast and 1.7 vs 11, p = 0.07 for the right breast.) As for the NTCP, our data point out that IMRT is not always likely to significantly increase the NTCP to OARs.
  
  
  CONCLUSIONS
  In HL male patients IMRT seems feasible and accurate while for women HL patients IMRT should be used with caution.
authors.affiliation: Departments of Radiotherapy, Sant'Andrea Hospital, Via di Grottarossa 1035/1039, 00189, Rome, Italy.
authors.forename: Vitaliana
authors.initials: V
authors.lastname: De Sanctis
authors.forename: Chiara
authors.initials: C
authors.lastname: Bolzan
authors.forename: Marco
authors.initials: M
authors.lastname: D'Arienzo
authors.forename: Stefano
authors.initials: S
authors.lastname: Bracci
authors.forename: Alessandro
authors.initials: A
authors.lastname: Fanelli
authors.forename: Maria Christina
authors.initials: MC
authors.lastname: Cox
authors.forename: Maurizio
authors.initials: M
authors.lastname: Valeriani
authors.forename: Mattia F
authors.initials: MF
authors.lastname: Osti
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Minniti
authors.forename: Laura
authors.initials: L
authors.lastname: Chiacchiararelli
authors.forename: Riccardo Maurizi
authors.initials: RM
authors.lastname: Enrici
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006689:Hodgkin Disease / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D058958:Organs at Risk / Q000528:radiation effects*; D011379:Prognosis; D011832:Radiation Injuries / Q000517:prevention & control*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal; D050397:Radiotherapy, Intensity-Modulated; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D055815:Young Adult