Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Jul 27, 2015; 7(7): 116-122
Published online Jul 27, 2015. doi: 10.4240/wjgs.v7.i7.116
Accuracy of computed tomography in nodal staging of colon cancer patients
Audrey H Choi, Rebecca A Nelson, Hans F Schoellhammer, Won Cho, Michelle Ko, Amanda Arrington, Christopher R Oxner, Marwan Fakih, Jimmie Wong, Stephen M Sentovich, Julio Garcia-Aguilar, Joseph Kim
Audrey H Choi, Hans F Schoellhammer, Won Cho, Michelle Ko, Amanda Arrington, Christopher R Oxner, Stephen M Sentovich, Julio Garcia-Aguilar, Joseph Kim, Department of Surgery, City of Hope National Medical Center, Duarte, CA 91010, United States
Rebecca A Nelson, Department of Biostatistics, City of Hope National Medical Center, Duarte, CA 91010, United States
Marwan Fakih, Department of Medical Oncology, City of Hope National Medical Center, Duarte, CA 91010, United States
Jimmie Wong, Department of Radiology, City of Hope National Medical Center, Duarte, CA 91010, United States
Author contributions: Choi AH and Nelson RA contributed equally to this work; Garcia-Aguilar J and Kim J designed the research; Choi AH, Schoelhammer HF, Cho W, Ko M, Arrington A, Oxner CR, Wong J and Garcia-Aguilar J acquired the data; Choi AH, Nelson RA, Schoelhammer HF, Cho W and Oxner CR analyzed the data; Choi AH, Nelson RA, Schoelhammer HF, Cho W and Ko M wrote the manuscript; Arrington A, Oxner CR, Fakih M, Wong J, Sentovich SM, Garcia-Aguilar J and Kim J provided critical revisions for intellectual content; all authors provided final approval of the manuscript.
Institutional review board statement: The study was reviewed and approved by the City of Hope Institutional Review Board.
Informed consent statement: N/A.
Conflict-of-interest statement: The authors have no relevant disclosures pertaining to this work.
Data sharing statement: Dataset available from the corresponding author at jokim@coh.org.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Joseph Kim, MD, Department of Surgery, City of Hope National Medical Center, 1500 East Duarte Rd, Duarte, CA 91010, United States. jokim@coh.org
Telephone: +1-626-4767100 Fax: +1-626-3018865
Received: March 3, 2015
Peer-review started: March 3, 2015
First decision: March 20, 2015
Revised: April 6, 2015
Accepted: June 9, 2015
Article in press: June 11, 2015
Published online: July 27, 2015
Abstract

AIM: To predict node-positive disease in colon cancer using computed tomography (CT).

METHODS: American Joint Committee on Cancer stage I-III colon cancer patients who underwent curavtive-intent colectomy between 2007-2010 were identified at a single comprehensive cancer center. All patients had preoperative CT scans with original radiology reports from referring institutions. CT images underwent blinded secondary review by a surgeon and a dedicated abdominal radiologist at our institution to identify pericolonic lymph nodes (LNs). Comparison of outside CT reports to our independent imaging review was performed in order to highlight differences in detection in actual clinical practice. CT reviews were compared with final pathology. Results of the outside radiologist review, secondary radiologist review, and surgeon review were compared with the final pathologic exam to determine sensitivity, specificity, positive and negative predictive values, false positive and negative rates, and accuracy of each review. Exclusion criteria included evidence of metastatic disease on CT, rectal or appendiceal involvement, or absence of accompanying imaging from referring institutions.

RESULTS: From 2007 to 2010, 64 stageI-III colon cancer patients met the eligibility criteria of our study. The mean age of the cohort was 68 years, and 26 (41%) patients were male and 38 (59%) patients were female. On final pathology, 26 of 64 (40.6%) patients had node-positive (LN+) disease and 38 of 64 (59.4%) patients had node-negative (LN-) disease. Outside radiologic review demonstrated sensitivity of 54% (14 of 26 patients) and specificity of 66% (25 of 38 patients) in predicting LN+ disease, whereas secondary radiologist review demonstrated 88% (23 of 26) sensitivity and 58% (22 of 38) specificity. On surgeon review, sensitivity was 69% (18 of 26) with 66% specificity (25 of 38). Secondary radiology review demonstrated the highest accuracy (70%) and the lowest false negative rate (12%), compared to the surgeon review at 67% accuracy and 31% false negative rate and the outside radiology review at 61% accuracy and 46% false negative rate.

CONCLUSION: CT LN staging of colon cancer has moderate accuracy, with administration of NCT based on CT potentially resulting in overtreatment. Active search for LN+ may improve sensitivity at the cost of specificity.

Keywords: Colon cancer, Lymph nodes, Clinical staging, Computed tomography, Neoadjuvant therapy

Core tip: Clinical staging to determine eligibility for neoadjuvant trials requires accurate imaging. This study compares lymph node identification on preoperative computed tomography (CT) scans by outside radiologists, a tertiary cancer center radiologist and a surgeon, mirroring referral patterns to tertiary care facilities. While re-review of CT scans by a tertiary center radiologist improved sensitivity of lymph node detection, CT staging of colon cancer demonstrated moderate accuracy overall. Our findings suggest that the administration of neoadjuvant chemotherapy based on preoperative CT staging would potentially result in overtreatment of colon cancer patients.