Detection of recurrent colorectal cancer by 18F-FDG PET/CT comparison with contrast enhanced CT scan.
OBJECTIVE
To evaluate diagnostic performance of 18F-FDG PET/CT in assessment of recurrence colorectal cancer after treatment in Siriraj Hospital.


METHODS
The authors retrospectively studied 48 treated colorectal cancer patients with suspected recurrence who underwent 18F-FDG PET/CT and contrast-enhanced CT (CECT). Clinical information, image follow-up for at least one year, and pathological reports of the patients were reviewed for gold standard


RESULTS
Recurrent or metastatic disease was found in 36 of 48 patients. Calculated sensitivity, specificity and accuracy of 18F-FDG PET/CT were 94.4%, 66.7%, and 87.5%. 18F-FDG PET/CT can reduce false positive results of CECT in six patients, thus specificity of 18F-FDG PET/CT was statistically significantly better than that of CECT. Using lesion-based analysis with 65 recurrent sites and 26 non-recurrent lesion, 18F-FDG PET/CT showed better sensitivity 87.7%, specificity 61.5%, and accuracy 80.2 than CECT without statistical significance.


CONCLUSIONS
18F-FDG PET/CT overall showed higher sensitivity, specificity, and accuracy than CECT.
Division of Nuclear Medicine, Department of Radiology, Siriraj Hospital, Mahidol University, Bangkok, Thailand. sunanta.chi@mahidol.ac.th
Sunanta
S
Chiewvit
Titiporn
T
Jiranantanakorn
Piyaporn
P
Apisarnthanarak
Potjanee
P
Kanchaanapiboon
Chompunoot
C
Hannanthawiwat
Kritaya
K
Ubolnuch
Nopparat
N
Phongsawat
Pipat
P
Chiewvit
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000628:therapy; D003287:Contrast Media; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000628:therapy; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000628:therapy; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18