title: Comparison of FDG PET/CT and MRI in lymph node staging of endometrial cancer.
abstract: OBJECTIVE
  Endometrial cancer is the most frequent cancer occurring in the female genital tract in the Western countries. Because surgical staging is currently the standard, noninvasive techniques that accurately identify lymph node (LN) metastases would be beneficial by reducing costs and complications. The purpose of our study is to compare the diagnostic accuracy of 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) with that of magnetic resonance imaging (MRI) for detecting LN metastases in the preoperative staging of endometrial cancer.
  
  
  METHODS
  Two hundred eighty-seven consecutive patients with endometrial cancer underwent preoperative PET/CT and MRI for staging. The malignancy criteria for LNs were a short diameter of 1 cm or more by MRI and focally increased (18)F-FDG uptake by PET/CT. After evaluating PET/CT and MRI separately, morphologic and functional image findings were compared with the histological findings regarding LN metastasis for all patients. PET/CT and MRI images were classified on the basis of histological findings as true-positive, true-negative, false-positive, or false-negative. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated.
  
  
  RESULTS
  Histologic examination revealed LN metastases in 51 patients (17.8%). The maximal standardized uptake values (SUVmax) of the primary lesions by PET/CT ranged from 1.4 to 37.7, with a mean value of 9.3, whereas those of the metastatic LNs ranged from 2.0 to 22.5 with a mean of 7.3. On a per-patient basis, node staging resulted in sensitivities of 70.0% with (18)F-FDG PET/CT and 34.0% with MRI, and specificities of 95.4 % with PET/CT and 95.0% with MRI. The NPV of PET/CT was 94.3%, and that of MRI was 87.2%. On a lesion base analysis, sensitivity of PET/CT was 79.4% while that of MRI was 51.6%. In detecting distant metastasis, the sensitivity, specificity, accuracy, PPV, and NPV of PET/CT were 92.9, 98.9, 98.6, 81.3, and 99.6%, respectively.
  
  
  CONCLUSIONS
  Diagnostic performance of FDG PET/CT was better than MRI for detecting metastatic lymph nodes in patients with endometrial cancer both by patient basis and lesion basis analyses. Due to high NPV, FDG PET-CT could aid in selecting candidates for lymphadenectomy.
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Korea.
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Korea.
authors.forename: Arthur
authors.initials: A
authors.lastname: Cho
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Korea.
authors.forename: Mijin
authors.initials: M
authors.lastname: Yun
authors.affiliation: Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Institute of Women's Life Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Tae
authors.initials: YT
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul, 120-752, Korea. mdkwj@yuhs.ac.
authors.forename: Won Jun
authors.initials: WJ
authors.lastname: Kang
mesh_terms: D000328:Adult; D000368:Aged; D016889:Endometrial Neoplasms / Q000175:diagnosis* / Q000473:pathology* / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D064847:Multimodal Imaging; D009367:Neoplasm Staging / Q000379:methods*; D049268:Positron-Emission Tomography; D057234:Preoperative Period; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: 18F-fluoro-2-deoxy-D-glucose positron emission tomography; Endometrial cancer; Lymph node; Staging