title: Role of PET/CT in treatment planning for head and neck cancer patients undergoing definitive radiotherapy.
abstract: BACKGROUND
  In this study, we aimed to investigate the benefits of 18F-deoxyglucose positron emission tomography/computed tomography (FGD-PET/CT) imaging for staging and radiotherapy planning in patients with head and neck cancer undergoing definitive radiotherapy.
  
  
  METHODS
  Thirty-seven head and neck cancer patients who had undergone definitive radiotherapy and PET/CT at the Uludag University Medical Faculty Department of Radiation Oncology were investigated in order to determine the role of PET/CT in staging and radiotherapy planning.
  
  
  RESULTS
  The median age of this patient group of 32 males and 5 females was 57 years (13-84years). The stage remained the same in 18 cases, decreased in 5 cases and increased in 14 cases with PET/CT imaging. Total gross tumor volume (GTV) determined by CT (GTVCT-Total) was increased in 32 cases (86.5%) when compared to total GTV determined by PET/CT (GTVPET/CT-Total). The GTV of the primary tumor determined by PET/CT (GTVPET/CT) was larger in 3 cases and smaller in 34 cases compared to that determined by CT (GTVCT). The GTV of lymph nodes determined by PET/CT (GTVLNPET/CT) was larger in 20 cases (54%) and smaller in 12 cases (32.5%) when compared to GTV values determined by CT (GTVLNCT). No pathological lymph nodes were observed in the remaining five cases with both CT and PET/ CT.
  
  
  CONCLUSIONS
  We can conclude that PET/CT can significantly affect both pretreatment staging and assessed target tumor volume in patients with head and neck cancer. We therefore recommend examining such cases with PEC/CT before treatment.
authors.affiliation: Department of Radiation Oncology, Diyarbakir Gazi Yasargil Education and Research Hospital, Diyarbakir, Turkey E-mail : onurilyasoglu131202@yahoo.com.
authors.forename: Sonay
authors.initials: S
authors.lastname: Arslan
authors.forename: Candan Demiroz
authors.initials: CD
authors.lastname: Abakay
authors.forename: Feyza
authors.initials: F
authors.lastname: Sen
authors.forename: Ali
authors.initials: A
authors.lastname: Altay
authors.forename: Tayyar
authors.initials: T
authors.lastname: Akpinar
authors.forename: Ahmet Siyar
authors.initials: AS
authors.lastname: Ekinci
authors.forename: Onur
authors.initials: O
authors.lastname: Esbah
authors.forename: Nuri
authors.initials: N
authors.lastname: Uslu
authors.forename: Kezban Esra
authors.initials: KE
authors.lastname: Kekilli
authors.forename: Lutfi
authors.initials: L
authors.lastname: Ozkan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000532:radiotherapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18