Accuracy of high-resolution MRI with lumen distention in rectal cancer staging and circumferential margin involvement prediction.
OBJECTIVE
To evaluate the accuracy of magnetic resonance imaging (MRI) with lumen distention for rectal cancer staging and circumferential resection margin (CRM) involvement prediction.


METHODS
Seventy-three patients with primary rectal cancer underwent high-resolution MRI with a phased-array coil performed using 60-80 mL room air rectal distention, 1-3 weeks before surgery. MRI results were compared to postoperative histopathological findings. The overall MRI T staging accuracy was calculated. CRM involvement prediction and the N staging, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed for each T stage. The agreement between MRI and histological results was assessed using weighted-kappa statistics.


RESULTS
The overall MRI accuracy for T staging was 93.6% (k = 0.85). The accuracy, sensitivity, specificity, PPV and NPV for each T stage were as follows: 91.8%, 86.2%, 95.5%, 92.6% and 91.3% for the group ≤ T2; 90.4%, 94.6%, 86.1%, 87.5% and 94% for T3; 98,6%, 85.7%, 100%, 100% and 98.5% for T4, respectively. The predictive CRM accuracy was 94.5% (k = 0.86); the sensitivity, specificity, PPV and NPV were 89.5%, 96.3%, 89.5%, and 96.3% respectively. The N staging accuracy was 68.49% (k = 0.4).


CONCLUSIONS
MRI performed with rectal lumen distention has proved to be an effective technique both for rectal cancer staging and involved CRM predicting.
Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy. ; Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Elsa
E
Iannicelli
Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy. ; Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Sara
S
Di Renzo
Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Mario
M
Ferri
Department of Clinical and Molecular Sciences, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Emanuela
E
Pilozzi
Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy. ; Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Marco
M
Di Girolamo
Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy. ; Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Alessandra
A
Sapori
Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Vincenzo
V
Ziparo
Radiology Institute, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy. ; Department of Surgical and Medical Sciences and Translational Medicine, Faculty of Medicine and Psychology, University of Rome, Sapienza, Sant'Andrea Hospital, Rome 00189, Italy.
Vincenzo
V
David
D000328:Adult; D000368:Aged; D000388:Air; D004106:Dilatation / Q000379:methods; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery; D012007:Rectum / Q000473:pathology*; D012680:Sensitivity and Specificity
Rectum MR; Rectum NEOPLASM; Rectum staging