title: The impact of image fusion in resolving discrepant findings between FDG-PET and MRI/CT in patients with gynaecological cancers.
abstract: This study was performed to prospectively investigate the impact of image fusion in resolving discrepant findings between fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) or X-ray computed tomography (CT) in patients with gynaecological cancers. Discrepant findings were defined as lesions where the difference between the FDG-PET and MRI/CT images was assigned a value of at least 2 on a 5-point probability scale. The FDG-PET and MRI/CT images were taken within 1 month of each other. Image fusion between FDG-PET and CT was performed by automatic registration between the two images. During an 18-month period, 34 malignant lesions and seven benign lesions from 32 patients who had undergone either surgical excision or a CT-guided histopathological investigation were included for analysis. Among these cases, image fusion was most frequently required to determine the nature and/or the extent of abdominal and pelvic lesions (28/41, 68%), especially as regards peritoneal seeding (8/41, 20%). Image fusion was most useful in providing better localisation for biopsy (16/41, 39%) and in discriminating between lesions with pathological versus physiological FDG uptake (12/41, 29%). Image fusion changed the original diagnosis based on MRI/CT alone in 9/41 lesions (22%), and the original diagnosis based on FDG-PET alone in 5/41 lesions (12%). It led to alteration of treatment planning (surgery or radiotherapy) in seven of the 32 patients (22%). In patients with gynaecological cancers, the technique of image fusion is helpful in discriminating the nature of FDG-avid lesions, in effectively localising lesions for CT-guided biopsy and in providing better surgical or radiotherapy planning.
authors.affiliation: Department of Nuclear Medicine, Chang Gung Memorial Hospital and Chang Gung University, Taipei, Taiwan.
authors.forename: Cheng-Chien
authors.initials: CC
authors.lastname: Tsai
authors.forename: Chien-Sheng
authors.initials: CS
authors.lastname: Tsai
authors.forename: Koon-Kwan
authors.initials: KK
authors.lastname: Ng
authors.forename: Chyong-Huey
authors.initials: CH
authors.lastname: Lai
authors.forename: Swei
authors.initials: S
authors.lastname: Hsueh
authors.forename: Pan-Fu
authors.initials: PF
authors.lastname: Kao
authors.forename: Ting-Chang
authors.initials: TC
authors.lastname: Chang
authors.forename: Ji-Hong
authors.initials: JH
authors.lastname: Hong
authors.forename: Tzu-Chen
authors.initials: TC
authors.lastname: Yen
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D005833:Genital Neoplasms, Female / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014055:Tomography, Emission-Computed / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18