Recurrent rectal cancer: diagnosis with dynamic MR imaging.
OBJECTIVE
To evaluate whether dynamic magnetic resonance (MR) imaging can increase the diagnostic accuracy in suspected local recurrence of rectal carcinoma.


METHODS
Eighteen patients (seven men, 11 women, aged 26-78 years) with 19 suspect lesions were examined. T1-weighted (pre- and postcontrast) and T2-weighted spin-echo images were read by three observers. Computed tissue-specific enhancement parameters were obtained and displayed on gray-scale images (pharmacokinetic mapping).


RESULTS
Reading of the spin-echo images yielded a sensitivity of 91%-100% (confidence interval, 67%, 100%), a specificity of 29%-43% (12%, 67%), and an accuracy of 71%-75% (48%, 91%). Analysis of the MR data showed greater (P = .0038) and faster (P = .0018) enhancement of malignant lesions (n = 12) compared with benign lesions (n = 7).


CONCLUSIONS
Pharmacokinetic mapping of dynamic MR imaging data allows in vivo insight into tissue physiopathology, helping differentiate benign from malignant pelvic lesions in rectal cancer.
Müller-Schimpfle
M
M
Research Program Radiological Diagnostics and Therapy, German Cancer Research Center, Heidelberg.
Brix
G
G
Layer
G
G
Schlag
P
P
Engenhart
R
R
Frohmuller
S
S
Hess
T
T
Zuna
I
I
Semmler
W
W
van Kaick
G
G
D000328:Adult; D000368:Aged; D003287:Contrast Media; D003937:Diagnosis, Differential; D004338:Drug Combinations; D005260:Female; D005682:Gadolinium; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000453:epidemiology; D009942:Organometallic Compounds; D004369:Pentetic Acid / Q000031:analogs & derivatives; D011237:Predictive Value of Tests; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D012680:Sensitivity and Specificity
D003287:Contrast Media; D004338:Drug Combinations; D009942:Organometallic Compounds; D008536:Meglumine; D004369:Pentetic Acid; D005682:Gadolinium; D019786:Gadolinium DTPA