Neither FDG-PET nor CT can distinguish between a pathological complete response and an incomplete response after neoadjuvant chemoradiation in locally advanced rectal cancer: A prospective study Journal Article


Authors: Guillem, J. G.; Ruby, J. A.; Leibold, T.; Akhurst, T. J.; Yeung, H. W.; Gollub, M. J.; Ginsberg, M. S.; Shia, J.; Suriawinata, A. A.; Riedel, E. R.; Mazumdar, M.; Saltz, L. B.; Minsky, B. D.; Nash, G. M.; Paty, P. B.; Temple, L. K.; Weiser, M. R.; Larson, S. M.
Article Title: Neither FDG-PET nor CT can distinguish between a pathological complete response and an incomplete response after neoadjuvant chemoradiation in locally advanced rectal cancer: A prospective study
Abstract: OBJECTIVE:: To prospectively compare the ability of flourodeoxyglucose- positron emission tomography (FDG-PET) and computed tomography (CT) to identify a pathological complete response (pCR) in patients with rectal cancer treated by chemoradiation. BACKGROUND:: A major obstacle in pursuing nonoperative management in patients with rectal cancer after chemoradiation is the inability to identify a pCR preoperatively. METHODS:: A total of 121 patients with rectal cancer were prospectively enrolled. FDG-PET scans and helical CT scans were obtained before and after neoadjuvant chemoradiation. Consensus readings of PET and CT scans were used to classify certainty of disease (5-point confidence rating scale). The ability of PET and CT scans to accurately distinguish a pCR (ypT0) from an incomplete response (ypT1-4) was estimated using the area under the receiver operating characteristic curve (AUC). RESULTS:: Of the 121 patients, 26 (21%) had a pCR. PET and CT scans were equally inadequate at distinguishing a pCR from an incomplete response (AUC = 0.64 for both, P = 0.97). Among the 26 patients with a pCR, 14 (54%) and 5 (19%) were classified as complete responders on PET and CT scans, respectively. Among the 95 patients with an incomplete pathological response, 63 (66%) and 90 (95%) were classified as incomplete responders on PET and CT scans, respectively. None of the individual PET parameters, including visual response score, mean standard uptake value (SUVmean), maximum SUV (SUVmax), and total lesion glycolysis, accurately distinguished a pCR (AUCs = 0.57-0.73). CONCLUSIONS:: Neither PET nor CT scans have adequate predictive value to be clinically useful in distinguishing a pCR from an incomplete response and, therefore, should not be obtained for the purpose of attempting to predict a pCR after neoadjuvant chemoradiation for rectal cancer. Copyright © 2013 Lippincott Williams & Wilkins.
Keywords: adult; cancer chemotherapy; treatment outcome; treatment response; aged; aged, 80 and over; middle aged; major clinical study; cancer localization; advanced cancer; area under the curve; comparative study; neoadjuvant therapy; positron emission tomography; prospective study; prospective studies; radiopharmaceuticals; polymerase chain reaction; adenocarcinoma; computer assisted tomography; tomography, spiral computed; conservative treatment; fluorodeoxyglucose f 18; fluorodeoxyglucose f18; positron-emission tomography; response; rectal neoplasms; rectum cancer; glycolysis; roc curve; computed tomography; receiver operating characteristic; pet scanner; rectal cancer; rectum; preoperative radiotherapy; chemoradiation therapy; adjuvant chemoradiotherapy; chemoradiotherapy, adjuvant; nonoperative approach; wait and see
Journal Title: Annals of Surgery
Volume: 258
Issue: 2
ISSN: 0003-4932
Publisher: Lippincott Williams & Wilkins  
Date Published: 2013-08-01
Start Page: 289
End Page: 295
Language: English
DOI: 10.1097/SLA.0b013e318277b625
PROVIDER: scopus
PUBMED: 23187748
DOI/URL:
Notes: --- - "Export Date: 1 August 2013" - "CODEN: ANSUA" - "Source: Scopus"
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MSK Authors
  1. Leonard B Saltz
    592 Saltz
  2. Philip B Paty
    372 Paty
  3. Bruce Minsky
    263 Minsky
  4. Marc J Gollub
    109 Gollub
  5. Michelle S Ginsberg
    158 Ginsberg
  6. Madhu Mazumdar
    123 Mazumdar
  7. Henry W D Yeung
    127 Yeung
  8. Jose Guillem
    371 Guillem
  9. Tobias Leibold
    11 Leibold
  10. Jinru Shia
    459 Shia
  11. Martin R Weiser
    344 Weiser
  12. Jeannine Alberts Ruby
    8 Ruby
  13. Timothy J Akhurst
    134 Akhurst
  14. Garrett Nash
    135 Nash
  15. Larissa Temple
    178 Temple
  16. Steven M Larson
    774 Larson