Learning objectives
To provide an educational and pictorial review of the magnetic resonance imaging (MRI) findings of rectal carcinoma,
illustrated with cases of our institution.
To highlight the main pitfalls in MRI rectal cancer staging.
Background
Rectal cancer is one of the major causes of cancer-related mortality worldwide.
Imaging plays a central role in the pre-treatment evaluation of pathology-proven tumors,
providing loco-regional (MRI) and distant staging (CT).
MRI has established itself as the primary and decisive non-invasive method for loco-regional staging in patients with rectal cancer,
mainly due to its sharp contrast and high soft tissue resolution on T2-weighted imaging[1-4].
MRI can depict very precisely the interface between the rectal muscularis propria and the mesorectal fat,
very important for local staging...
Findings and procedure details
In this section,
we review MRI technique,
along with illustrations of important anatomic MRI landmark,
key MRI findings for different local stages of rectal adenocarcinoma are described and illustrated with cases from our institution.
MRI Technique
In our institution rectal cancer staging is performed in a 1.5T MR scanner,
using a 10ch torso coil,
with no prior patient preparation (unless fasting for the last 4 hours) and scopolamine intravenous administration.
Our standard rectal cancer staging MRI protocol consists of T2 weighted-images in direct axial and...
Conclusion
MRI is the modality of choice for staging and treatment planning of rectal cancer.
Familiarity with key radiological MRI features,
along with the main pitfalls and knowledge of rectal cancer local staging is important to correctly stage and accurately report,
so appropriate treatment options can be considered.
References
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Martling A,
Holm T,
Bremmer S (2003) Prognostic value of preoperative magnetic resonance imaging of the pelvis in rectal cancer.
Br J Surg 90 (11):1422–1428
2.
Brown G,
Davies S,
Williams GT et al.
(2004) Effectiveness of preoperative staging in rectal cancer: digital rectal examination,
endoluminal ultrasound or magnetic resonance imaging? Br J Cancer 91(1):23–29
3.
LeBlanc J (2007) Imaging and management of rectal cancer.
Nat Clin Pract Gastroenterol Hepatol 4(12):665–676
4.
Smith N,
Brown G et al.
(2008) Preoperative staging in rectal cancer....