Preoperative chemo-radiation-induced ulceration in patients with esophageal cancer: a confounding factor in tumor response assessment in integrated computed tomographic-positron emission tomographic imaging.
OBJECTIVE
Positron emission tomography can be useful in predicting response of esophageal cancer after preoperative chemo-radiation therapy (CRT). We evaluated the use of integrated computed tomography (CT)-PET among patients with esophageal cancer being considered for resection after CRT.


METHODS
Three reviewers blinded to clinical and pathologic staging retrospectively reviewed the CT-PET scans of patients with esophageal cancer after preoperative CRT who underwent esophagectomy. [F]-fluoro-2-deoxy-D-glucose uptake for residual malignancy was determined by visual analysis and semi-quantitatively when standardized uptake value (SUV) was > or =4.


RESULTS
Forty-two patients underwent esophageal resection. Using visual analysis, CT-PET had a sensitivity of 47% and specificity of 58% in detecting residual malignancy. Using semi-quantitative analysis, 19 patients had a SUV > or =4 in the region of the primary esophageal tumor and were interpreted as having residual malignancy (sensitivity 43%, specificity 50%). Of these 19, six had complete pathologic response to CRT. These false-positive results, due to therapy-induced ulceration detected at endoscopy, limit the use of CT-PET alone in detecting residual malignancy. Similarly, sensitivity (25%) and specificity (73%) of endoscopy/biopsy in detecting residual malignancy were poor. However, the accuracy of CT-PET in detecting residual malignancy was improved when combined with endoscopic findings. In the absence of ulceration at endoscopy, 8 of 8 patients with SUV > or =4 after chemo-radiation had residual malignancy at surgery.


CONCLUSIONS
CRT-induced ulceration results in false-positive results on CT-PET and precludes accurate detection of residual esophageal tumor. However, CT-PET in combination with endoscopy is useful in identifying patients with a high risk of residual tumor post-CRT.
Erasmus
Jeremy J
JJ
Department of Diagnostic Imaging, University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. jerasmus@di.mdacc.tmc.edu
Munden
Reginald F
RF
Truong
Mylene T
MT
Ho
Jeremy J
JJ
Hofstetter
Wayne L
WL
Macapinlac
Homer A
HA
Correa
Arlene M
AM
Wu
Tsung-Teh
TT
Bruzzi
John F
JF
Marom
Edith M
EM
Sabloff
Bradley S
BS
Ajani
Jaffer A
JA
Komaki
Ritsuko
R
Liao
Zhongxing
Z
Lee
Jeffrey H
JH
Fukami
Norio
N
Bresalier
Robert
R
Swisher
Stephen G
SG
D000328:Adult; D000368:Aged; D003131:Combined Modality Therapy / Q000009:adverse effects; D004935:Esophageal Diseases / Q000209:etiology*; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D016629:Esophagectomy; D004945:Esophagoscopy; D005189:False Positive Reactions; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014456:Ulcer / Q000209:etiology*
D019788:Fluorodeoxyglucose F18