title: Assessing the impact of FDG-PET in the management of anal cancer.
abstract: OBJECTIVE
  To assess the utility of FDG-PET in anal cancer for staging and impact on radiotherapy planning (RTP), response and detection of recurrent disease.
  
  
  METHODS
  Fifty histopathological anal cancer patients were reviewed between 1996 and 2006. The median age was 58 years (range 36-85) with 19 males:31females. Clinical assessment with CT was compared to PET. Impact on management, disease response, recurrence and metastases was evaluated.
  
  
  RESULTS
  The non-PET staging was Stage I(8), Stage II(18), Stage III(22), and Stage IV(2)s. The primary was strongly FDG avid in 98% with non-excised tumors compared to CT (58%). PET upstaged 17% with unsuspected pelvic/inguinal nodal disease. Pre-treatment PET identified 11 additional by involved nodal groups in 48 patients causing RTP amendments in 19%. Post-treatment PETs at median 17 weeks (range 9-28) showed complete responses in 20 (80%) and 5 (20%) partial responses (PR). PRs were biopsy positive in 2 and negative in 3. Fifteen had follow-up scans of which all nine PETs detected recurrences were pathologically confirmed.
  
  
  CONCLUSIONS
  Anal cancer is FDG-PET avid. PET upstages 17% and changes the RTP in 19%. PET can aid in anal cancer staging and identification of residual disease, recurrent/metastatic disease but warrants further prospective studies.
authors.affiliation: Radiation Oncology Centre, Austin Health, Vic., Australia.
authors.forename: Brandon T
authors.initials: BT
authors.lastname: Nguyen
authors.forename: Daryl Lim
authors.initials: DL
authors.lastname: Joon
authors.forename: Vincent
authors.initials: V
authors.lastname: Khoo
authors.forename: George
authors.initials: G
authors.lastname: Quong
authors.forename: Michael
authors.initials: M
authors.lastname: Chao
authors.forename: Morikatsu
authors.initials: M
authors.lastname: Wada
authors.forename: Michael Lim
authors.initials: ML
authors.lastname: Joon
authors.forename: Andrew
authors.initials: A
authors.lastname: See
authors.forename: Malcolm
authors.initials: M
authors.lastname: Feigen
authors.forename: Kym
authors.initials: K
authors.lastname: Rykers
authors.forename: Cynleen
authors.initials: C
authors.lastname: Kai
authors.forename: Eddy
authors.initials: E
authors.lastname: Zupan
authors.forename: Andrew
authors.initials: A
authors.lastname: Scott
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001005:Anus Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging* / Q000532:radiotherapy / Q000556:secondary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18