Brief Articles
Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Sep 21, 2009; 15(35): 4434-4438
Published online Sep 21, 2009. doi: 10.3748/wjg.15.4434
Paraaortic lymph node metastasis in patients with intra-abdominal malignancies: CT vs PET
Mi-Jung Lee, Mi Jin Yun, Mi-Suk Park, Seung Hwan Cha, Myeong-Jin Kim, Jong Doo Lee, Ki Whang Kim
Mi-Jung Lee, Mi-Suk Park, Seung Hwan Cha, Myeong-Jin Kim, Ki Whang Kim, Department of Diagnostic Radiology, Research Institute of Radiological Science, and Institute of Gastroenterology, Yonsei University, College of Medicine, 134 Sincheon-Dong Seodaemun-Gu, Seoul 120-752, South Korea
Mi Jin Yun, Jong Doo Lee, Department of Nuclear medicine, Yonsei University, College of Medicine, 134 Sincheon-Dong Seodaemun-Gu, Seoul 120-752, South Korea
Seung Hwan Cha, Department of Diagnostic Radiology, Yonsei University, Wonju College of Medicine, Wonju 220-701, South Korea
Author contributions: Lee MJ and Park MS designed the research; Lee MJ, Park MS and Cha SH reviewed the CT images; Yun MJ and Lee JD reviewed the PET images; Lee MJ and Park MS wrote the paper; Kim MJ and Kim KW edited this paper.
Correspondence to: Mi-Suk Park, MD, Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 134 Sincheon-Dong Seodaemun-Gu, Seoul 120-752, South Korea. radpms@yuhs.ac
Telephone: +82-2-22287400 Fax: +82-2-3933035
Received: May 12, 2009
Revised: August 13, 2009
Accepted: August 20, 2009
Published online: September 21, 2009
Abstract

AIM: To compare the diagnostic accuracy of computed tomography (CT) and positron emission tomography (PET) for the preoperative detection of paraaortic lymph node (PAN) metastasis in patients with intra-abdominal malignancies.

METHODS: Sixty-six patients with intra-abdominal malignancies who underwent both CT and PET before lymphadenectomy were included in this study. Histopathologically, 13 patients had metastatic PAN, while 53 had non-metastatic PAN. The CT criteria for metastasis were: short diameter of > 8 mm, lobular or irregular shape, and/or combined ancillary findings, including necrosis, conglomeration, vessel encasement, and infiltration. The PET criterion was positive fluorodeoxyglucose (FDG) uptake. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of both modalities were compared with the pathologic findings, and the false positive and false negative cases with both CT and PET were analyzed.

RESULTS: The sensitivity, specificity, PPV, NPV, and accuracy of CT were 61.5%, 84.9%, 50%, 90% and 80.3%, respectively. For PET, the percentages were 46.2%, 100%, 100%, 88.3%, and 89.4%. Additionally, there were 8 false positive CT cases (8/53, 15.1%) and zero false positive PET cases. Of the 13 metastatic PANs, there were 5 false negative CT scans (38.5%) and 7 (53.9%) false negative PET scans.

CONCLUSION: For detecting PAN metastasis, CT is more sensitive than PET, while PET is more specific.

Keywords: Malignancy; Paraaortic lymph node; Computed tomography; Positron emission tomography; Sensitivity; Specificity