Preoperative T and N staging of colorectal cancer: accuracy of contrast-enhanced multi-detector row CT colonography--initial experience.
OBJECTIVE
To evaluate the accuracy of contrast material-enhanced multi-detector row computed tomographic (CT) colonography for preoperative staging of colorectal cancer.


METHODS
Forty-one patients with colorectal carcinoma underwent preoperative contrast-enhanced multi-detector row CT colonography. Images were obtained in the arterial (start delay of 35 seconds) and portal venous (start delay of 70 seconds) phases. The arterial phase was focused on the suspected region of neoplasm, whereas the venous phase included the whole abdomen and pelvis. Two radiologists independently evaluated the depth of tumor invasion into the colorectal wall (T) and regional lymph node involvement (N) on transverse CT images alone and in combination with multiplanar reformations (MPRs). Disagreements were resolved by means of consensus. CT findings were compared with pathologic results, which served as the reference standard. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were assessed. Differences in accuracy for T and N staging were assessed by using the McNemar test.


RESULTS
In T staging, overall accuracy was 73% when transverse images were evaluated alone and 83% when they were evaluated in combination with MPRs. This difference was not significant. N staging was associated with an overall accuracy of 59% with transverse images alone and 80% with combined transverse and MPR images (P <.01).


CONCLUSIONS
Contrast-enhanced multi-detector row CT colonography is an accurate technique for preoperative local staging of colorectal tumors.
Department of Clinical Sciences and Bioimages, Section of Radiology, SS Annunziata Hospital, G. D'Annunzio University, Via dei Vestini, 66013 Chieti, Italy. a.filippone@rad.umich.it
Antonella
A
Filippone
Roberta
R
Ambrosini
Maurizio
M
Fuschi
Tiziana
T
Marinelli
Domenico
D
Genovesi
Lorenzo
L
Bonomo
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023881:Colonography, Computed Tomographic; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D003287:Contrast Media; D013505:Digestive System Surgical Procedures; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015588:Observer Variation; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D012680:Sensitivity and Specificity
D003287:Contrast Media