The Value Of MRI In Predicting T Staging Of Rectal Cancer And Circumferential Resection Margin

Objectives: To assess the value of MRI in predicting T staging of rectal cancer and circumferential resection margin.Methods: From October 2014 to March 2015, forty five patient pathologically confirmed rectal cancer with pathologically confirmed in the first Affiliated Hospital of Fujian Medical University, including 28 males and 17 females, aged 32-79 years, mean age of 61.60 years of age and clinical manifestations were stool and change in bowel habits. Use Siemens Avanto 3.0 T superconductive MR scanner and pelvic phased-array coil to scan whole pelvic and assess T staging of rectal cancer and circumferential resection margin status with applying turbo spin-echo(TSE) sequence. All patients were treated with surgery after MRI examination, operation in accordance with the principles of total mesorectal excision(TME), of which 36 patients underwent Dixon surgery,8 patients underwent Miles surgery, patients underwent Hartmann surgery. The MRI results were compared with pathological results to assess MRI for the predictive value of T staging and circumferential margin.Results: Thirty two cases were assessed correctly by MRI for T stage. Nine cases who were pathologically diagnosed as T1-2 stage were reported highly as T3 stage by MRI. Two cases who were pathologically diagnosed as T3 stage were reported highly as T4 stage.One with T4 stage tumor were reported lowly as T3 stage by MRI. One with T3 stage tumor was reported lowly as T1 stage by MRI. The overall MRI diagnostic accuracy for T stage was 71.1%(32/45),T1-2 stage was 90.9%(10/11), T3 stage was 62.9%(17/27), T4 stage was 71.4%(5/7). The results were statistic analyzed by Kappa test and the value of Kappa was 0.526 so that both have moderate consistency for T staging. Forty two cases were assessed correctly by MRI for circumferential resection margin status. Three with positive circumferential resection margin were reported lowlyas negative by MRI. The diagnostic accuracy for circumferential resection margin was 93.3%(42/45),the sensitivity was 100%(7/7),the specificity 92.1%(35/38), the positive predictive value 70.0%(7/10),the negative predictive value 100.0%(35/35). The results were statistic analyzed by Kappa test and the value of Kappa was 0.784 so that both has excellent consistency for diagnosing circumferential resection margin.Conclusions: MRI can predict T stage of rectal cancer and have a excellent accuracy in diagnosing circumferential resection margin status.