Rectal tumor stage: correlation of endorectal MR imaging and pathologic findings.
OBJECTIVE
To develop magnetic resonance (MR) imaging criteria for staging rectal cancer.


METHODS
Thirty-six patients with rectal tumors underwent MR imaging with an endorectal surface coil. MR images were compared with specimens from the resected tumor.


RESULTS
Rectal wall layers were reliably demonstrated. The MR imaging-determined tumor stage agreed with pathologic findings in 81% of cases. A retrospective review found the integrity of the rectal wall layers at the lesion center an accurate criterion for interpreting the local extent of the lesion. Lymph nodes as small as 2 mm were demonstrated. Although sensitive for demonstrating perirectal adenopathy, MR imaging had a specificity of only 72% for N1 disease.


CONCLUSIONS
Endorectal surface coil MR imaging shows promise for staging rectal lesions. Additional studies are necessary to further establish criteria for interpreting the images.
Schnall
M D
MD
Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia 19104.
Furth
E E
EE
Rosato
E F
EF
Kressel
H Y
HY
D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology*; D012007:Rectum / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity