Staging rectal cancer with MRI
With the advent of powerful gradient coil systems and high-resolution surface coils, magnetic resonance imaging (MRI) has come into tis own in being able to assess the relationship of a rectal tumor to surrounding organs and tissues. MRI is currently the only imaging modality that is highly accurate in predicting whether or not it is likely that a tumor can be resected without leaving cells behind and, therefore, provides important information for planning effective surgery versus chemotehrapy and radiation, especially in patients with advanced rectal cancer. It enables selection of surgery versus chemotherapy and radiation as treatment for localized rectal cancer.
MRI is recommended in selected cases by the European Guideline. One notable difference between this NICE guideline and the American NCCN guidelines is the use of ultrasound versus magnetic resonance imaging (MRI) for rectal cancer staging. In the US ultrasound is used more frequently for staging it and has advantages for discerning early and small cancers. Nevertheless, staging with MRI should still be considered medically appropriate even in the USA.
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