Dr Brown and colleagues from England assessed the accuracy of preoperative staging of rectal cancer.
The investigative team used magnetic resonance imaging to predict surgical circumferential resection margins.
The team conducted prospective observational study of rectal cancers treated by colorectal multidisciplinary teams between 2002 and 2003.
The investigators evaluated data from 11 colorectal units in four European countries.
The team evaluated 408 consecutive patients presenting with all stages of rectal cancer.
|87% of patients had a clear circumferential resection margin|
|British Medical Journal|
The patients underwent magnetic resonance imaging before total mesorectal excision surgery and histopathological assessment of the surgical specimen.
The main outcome was accuracy of magnetic resonance imaging in predicting a curative resection.
Curative resection was determined with the histological yardstick of presence or absence of tumour at the margins of the specimen.
The investigators found that 87% of patients had a clear circumferential resection margin.
Specificity for prediction of a clear margin by magnetic resonance imaging was 92%.
High resolution scans were technically satisfactory in 93%.
The investigators histopathologically graded surgical specimens as complete or moderate in 80%, and the median lymph node harvest was 12.
The team observed that magnetic resonance imaging predicted clear margins in 349 patients.
At surgery 327 had clear margins.
Dr Brown's team concludes, “High resolution magnetic resonance imaging accurately predicts whether the surgical resection margins will be clear or affected by tumor.”
“This technique can be reproduced accurately in multiple centres to predict curative resection.”
“It also warns the multidisciplinary team of potential failure of surgery, thus enabling selection of patients for preoperative treatment.”