title: Role of positron emission tomography-computed tomography in the management of anal cancer.
abstract: OBJECTIVE
  Pre- and post-treatment staging of anal cancer are often inaccurate. The role of positron emission tomograpy-computed tomography (PET-CT) in anal cancer is yet to be defined. The aim of the study was to compare PET-CT with CT scan, sentinel node biopsy results of inguinal lymph nodes, and anal biopsy results in staging and in follow-up of anal cancer.
  
  
  METHODS
  Fifty-three consecutive patients diagnosed with anal cancer underwent PET-CT. Results were compared with computed tomography (CT), performed in 40 patients, and with sentinel node biopsy (SNB) (41 patients) at pretreatment workup. Early follow-up consisted of a digital rectal examination, an anoscopy, a PET-CT scan, and anal biopsies performed at 1 and 3 months after the end of treatment. Data sets were then compared.
  
  
  RESULTS
  At pretreatment assessment, anal cancer was identified by PET-CT in 47 patients (88.7%) and by CT in 30 patients (75%). The detection rates rose to 97.9% with PET-CT and to 82.9% with CT (P=.042) when the 5 patients who had undergone surgery prior to this assessment and whose margins were positive at histological examination were censored. Perirectal and/or pelvic nodes were considered metastatic by PET-CT in 14 of 53 patients (26.4%) and by CT in 7 of 40 patients (17.5%). SNB was superior to both PET-CT and CT in detecting inguinal lymph nodes. PET-CT upstaged 37.5% of patients and downstaged 25% of patients. Radiation fields were changed in 12.6% of patients. PET-CT at 3 months was more accurate than PET-CT at 1 month in evaluating outcomes after chemoradiation therapy treatment: sensitivity was 100% vs 66.6%, and specificity was 97.4% vs 92.5%, respectively. Median follow-up was 20.3 months.
  
  
  CONCLUSIONS
  In this series, PET-CT detected the primary tumor more often than CT. Staging of perirectal/pelvic or inguinal lymph nodes was better with PET-CT. SNB was more accurate in staging inguinal lymph nodes.
authors.affiliation: Digestive and Colorectal Surgical Department, Centre of Minimal Invasive Surgery, University of Turin, Molinette Hospital, Turin, Italy. mistrangelo@katamail.com
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Mistrangelo
authors.forename: Ettore
authors.initials: E
authors.lastname: Pelosi
authors.forename: Marilena
authors.initials: M
authors.lastname: Bellò
authors.forename: Umberto
authors.initials: U
authors.lastname: Ricardi
authors.forename: Enrica
authors.initials: E
authors.lastname: Milanesi
authors.forename: Paola
authors.initials: P
authors.lastname: Cassoni
authors.forename: Massimo
authors.initials: M
authors.lastname: Baccega
authors.forename: Claudia
authors.initials: C
authors.lastname: Filippini
authors.forename: Patrizia
authors.initials: P
authors.lastname: Racca
authors.forename: Adriana
authors.initials: A
authors.lastname: Lesca
authors.forename: Fernando H
authors.initials: FH
authors.lastname: Munoz
authors.forename: Gianluca
authors.initials: G
authors.lastname: Fora
authors.forename: Andrea
authors.initials: A
authors.lastname: Skanjeti
authors.forename: Francesca
authors.initials: F
authors.lastname: Cravero
authors.forename: Mario
authors.initials: M
authors.lastname: Morino
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000473:pathology; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001005:Anus Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D002295:Carcinoma, Transitional Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D051517:Digital Rectal Examination; D005189:False Positive Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D005472:Fluorouracil / Q000008:administration & dosage; D005500:Follow-Up Studies; D006801:Humans; D007264:Inguinal Canal; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage; D064847:Multimodal Imaging / Q000706:statistics & numerical data*; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography; D011351:Proctoscopy / Q000706:statistics & numerical data; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy / Q000706:statistics & numerical data*; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D016685:Mitomycin; D005472:Fluorouracil