title: The effect of amifostine or IMRT to preserve the parotid function after radiotherapy of the head and neck region measured by quantitative salivary gland scintigraphy.
abstract: OBJECTIVE
  In this retrospective study, two approaches to preserve the parotid function after radiotherapy (RT) were compared: application of the radioprotective agent amifostine during RT and parotid-sparing intensity-modulated radiotherapy (IMRT).
  
  
  METHODS
  Patients were qualified for this analysis if (1) both parotid glands received a radiation dose of >or=50Gy using conventional radiotherapy techniques (cRT) or if they received a parotid-sparing IMRT as alternative, if (2) salivary gland scintigraphies before and after RT were performed, and if (3) a normal parotid function was present before RT. Quantitative salivary gland scintigraphy was used to assess the parotid gland function.
  
  
  RESULTS
  Altogether 275 salivary gland scintigraphies of 100 patients were analyzed. The mean relative tracer uptake (DeltaU) of patients treated with cRT, cRT with amifostine and IMRT 1-12 months after RT was 0.59 (95%CI 0.54-0.65), 0.67 (95%CI 0.59-0.76), and 0.93 (95%CI 0.78-1.07), respectively. The mean relative DeltaU 13-47 months after RT was 0.40 (95%CI 0.32-0.49), 0.60 (95%CI 0.48-0.71), and 0.92 (95%CI 0.56-1.28). At 1-12 months after RT, ANOVA testing with post-hoc comparison using the Bonferroni correction showed a significant difference between IMRT and cRT (p<0.001) or IMRT and amifostine (p<0.01). The difference between amifostine and cRT was not significant during the first year. At 13-47 months after RT, the difference between cRT and amifostine was significant (p=0.02).
  
  
  CONCLUSIONS
  Our data suggest that both amifostine and IMRT are able to partially preserve the parotid function after radiotherapy. The effect of IMRT appeared to be much greater.
authors: Department of Radiation Oncology, University Hospital Hamburg-Eppendorf (UKE), Germany. volker.rudat@gmail.com
authors: Volker
authors: V
authors: Rudat
authors: Mark
authors: M
authors: Münter
authors: Dirk
authors: D
authors: Rades
authors: Knut A
authors: KA
authors: Grötz
authors: Amira
authors: A
authors: Bajrovic
authors: Uwe
authors: U
authors: Haberkorn
authors: Winfried
authors: W
authors: Brenner
authors: Jürgen
authors: J
authors: Debus
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004999:Amifostine / Q000627:therapeutic use*; D005260:Female; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000000981:diagnostic imaging* / Q000528:radiation effects*; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000627:therapeutic use*; D011877:Radionuclide Imaging; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D014987:Xerostomia / Q000517:prevention & control*
chemical_list: D011837:Radiation-Protective Agents; D004999:Amifostine