Related Experiment Videos
MRI of recurrent rectosigmoid carcinoma
J Markus1, B Morrissey, C deGara
1Department of Diagnostic Imaging, Henderson General Division, Hamilton, Ontario, Canada.
Abdominal Imaging
|May 1, 1997
Summary
This study identifies key MRI features to differentiate recurrent rectosigmoid carcinoma from scar tissue. High T2 signal, round margins, and significant contrast enhancement accurately detect recurrence.
Area of Science:
- Radiology
- Oncology
- Gastroenterology
Background:
- Distinguishing recurrent rectosigmoid carcinoma from postoperative fibrosis is clinically important.
- Magnetic Resonance Imaging (MRI) is frequently used for postoperative surveillance.
Purpose of the Study:
- To identify the most reliable MRI criteria for differentiating recurrent rectosigmoid carcinoma from benign postoperative fibrosis.
Main Methods:
- Prospective evaluation of 22 patients with suspected recurrent rectosigmoid carcinoma.
- Utilized T2-weighted and contrast-enhanced T1-weighted MRI sequences.
- Correlated MRI findings (T2 signal, margin shape, contrast enhancement) with histology and follow-up.
Main Results:
- A combination of high T2 signal, round margins, and >40% contrast enhancement achieved 92% accuracy.
- This combination demonstrated 100% sensitivity and 85% specificity for detecting recurrence.
- Specificity increased to 100% in patients over one year post-surgery.
Conclusions:
- High signal intensity on T2-weighted images is a crucial indicator.
- Round mass margins and significant contrast enhancement (>40%) are key differentiating features.
- These MRI criteria reliably distinguish recurrent rectosigmoid carcinoma from benign postoperative changes.