Preoperative staging of rectal cancer using magnetic resonance imaging with external phase-arrayed coils.
OBJECTIVE
Rectal cancer can be accurately staged preoperatively by magnetic resonance imaging (MRI) with external phase-arrayed coils.


METHODS
Comparison of MRIs with pathologic staging.


METHODS
University hospital.


METHODS
Twenty-eight consecutive patients with biopsy-proven rectal cancer who did not undergo irradiation.


METHODS
Patients underwent imaging using a 1.5-T MRI scanner with external phase-arrayed surface coils. Streaking of the perirectal fat and disruption of the bowel wall margin were interpreted as transmural invasion. Lymph nodes were defined as metastatic when they had a diameter of at least 0.5 cm. Tumors were staged according to the TNM staging system (American Joint Committee on Cancer guidelines) as confined to the bowel wall (T1-T2) and invading through the bowel wall (T3-T4). Patients underwent anterior resection (n = 15), abdominoperineal resection (n = 11), or local excision (n = 2).


METHODS
Calculation of sensitivity, specificity, and accuracy for invasion through the bowel wall and lymph node status.


RESULTS
Sensitivity of MRI in detecting invasion through the bowel wall was 89% (16/18), specificity was 80% (8/10), and accuracy was 86% (24/28). Sensitivity for malignant lymphadenopathy was 67% (8/12), specificity was 71% (10/14), and accuracy 69% (18/26).


CONCLUSIONS
Although more costly and not as accurate as endoscopic ultrasound, MRI with phase-arrayed coils had excellent sensitivity at detecting transmural penetration of rectal cancer.
Gagliardi
Giuseppe
G
Department of Surgical Oncology, School of Medicine, Yale University, 333 Cedar St, New Haven, CT 06520, USA.
Bayar
Sancar
S
Smith
Robert
R
Salem
Ronald R
RR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000295:instrumentation; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D012007:Rectum / Q000473:pathology*; D012680:Sensitivity and Specificity