title: Detection of extra-regional tumour recurrence with18F-FDG-PET/CT in patients with recurrent gynaecological malignancies being considered for radical salvage surgery.
abstract: OBJECTIVE
  To compare the detection rate of extra-regional metastases in patients with recurrent gynaecological malignancies being considered for radical salvage surgery with combined 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) compared to conventional imaging.
  
  
  METHODS
  A retrospective review was performed of all patients in a provincial database with recurrent gynaecological malignancies being considered for pelvic exenteration that underwent restaging with CT/PET between March 2011 and October 2014. Findings on PET and conventional imaging (CT±pelvic MRI) were abstracted. Disease sites were classified according to the location (regional nodal metastases, extra-regional nodal metastases, peritoneum, or other distant sites) and diagnostic certainty (definitive or equivocal). The proportion of patients positive for extra-regional recurrence was calculated for PET and conventional imaging. In addition, the proportion of patients with indeterminate lesions only was calculated for each modality and the sites of indeterminate findings were tabulated.
  
  
  RESULTS
  There were 85 patients (median age, 50 years; range: 30-81 years) with carcinoma of cervix (n=51), endometrium (n=18), vagina (n=6), or vulva (n=10). Extra-regional recurrence was detected in 8/85 (9.4%) and 24/85 (28.2%) patients on conventional imaging and PET, respectively (p=0.0017). The greatest impact of PET compared to conventional imaging was in the detection of extra-regional nodal metastases. PET had significantly fewer examinations equivocal for extra-regional recurrence versus conventional imaging (6/85 [7.1%] and 38/85 [44.7%], respectively, p<0.001).
  
  
  CONCLUSIONS
  In patients with recurrent gynaecological malignancies being considered for radical salvage surgery, PET may identify significantly more extra-regional recurrence than conventional imaging. PET may also result in fewer equivocal lesions. The impact of these results on patient management and outcome should be confirmed in future prospective trials.
authors.affiliation: Division of Gynecology Oncology, Department of Obstetrics and Gynecology, University of Toronto, Toronto, Canada; Princess Margaret Hospital, University of Toronto, Toronto, Canada.
authors.forename: H
authors.initials: H
authors.lastname: Brar
authors.affiliation: Division of Gynecology Oncology, Department of Obstetrics and Gynecology, University of Toronto, Toronto, Canada; Princess Margaret Hospital, University of Toronto, Toronto, Canada.
authors.forename: T
authors.initials: T
authors.lastname: May
authors.affiliation: Princess Margaret Hospital, University of Toronto, Toronto, Canada; Department of Medical Imaging, University of Toronto, Toronto, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Tau
authors.affiliation: Department of Clinical Programs, Cancer Imaging Program, Cancer Care Ontario, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Langer
authors.affiliation: Department of Clinical Programs, Cancer Imaging Program, Cancer Care Ontario, Canada.
authors.forename: P
authors.initials: P
authors.lastname: MacCrostie
authors.affiliation: Department of Radiation Medicine, University of Toronto, Toronto, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Han
authors.affiliation: Princess Margaret Hospital, University of Toronto, Toronto, Canada; Department of Medical Imaging, University of Toronto, Toronto, Canada. Electronic address: ur.metser@uhn.ca.
authors.forename: U
authors.initials: U
authors.lastname: Metser
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D005833:Genital Neoplasms, Female / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D016879:Salvage Therapy; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18