|author2=Authors of integrated Creative Commons article<ref name="Beets-TanLambregts2017">{{cite journal|last1=Beets-Tan|first1=Regina G. H.|last2=Lambregts|first2=Doenja M. J.|last3=Maas|first3=Monique|last4=Bipat|first4=Shandra|last5=Barbaro|first5=Brunella|last6=Curvo-Semedo|first6=Luís|last7=Fenlon|first7=Helen M.|last8=Gollub|first8=Marc J.|last9=Gourtsoyianni|first9=Sofia|last10=Halligan|first10=Steve|last11=Hoeffel|first11=Christine|last12=Kim|first12=Seung Ho|last13=Laghi|first13=Andrea|last14=Maier|first14=Andrea|last15=Rafaelsen|first15=Søren R.|last16=Stoker|first16=Jaap|last17=Taylor|first17=Stuart A.|last18=Torkzad|first18=Michael R.|last19=Blomqvist|first19=Lennart|title=Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting|journal=European Radiology|volume=28|issue=4|year=2017|pages=1465–1475|issn=0938-7994|doi=10.1007/s00330-017-5026-2}}</ref>
}}
=== Hardware ===
* Requires an external surface coil<ref name="Beets-TanLambregts2017"/>* 1.5T or 3.0T.<ref name="Beets-TanLambregts2017"/>
=== Patient preparation ===
* Use of an enema is not routinely recommended<ref name="Beets-TanLambregts2017"/>
* Include coronal sequence parallel to the anal canal to assess the relation between tumour and anal sphincter
==== Morphology ====
Morphology<ref name="Beets-TanLambregts2017"/>
* Solid - polypoid
* Mucinous
Circunferential location within the rectal wall<ref name="Beets-TanLambregts2017"/>
* e.g. from X to X o'clock
==== Distance from anorectal junction ====
* Distance from the anorectal junction to the lower pole of the tumour<ref name="Beets-TanLambregts2017"/>
==== Tumour length ====
Although the panel agreed unanimously There is agreement that ‘some measure of tumour size’
should be reported, there was no clear consensus on a specific metric, i.e. whether this should be one-dimensional, threedimensional or a volume measurement, and if and how after CRT an estimation of the tumour volume reduction should be provided. There is no solid evidence that favours one over
another, although some authors have suggested that, specifically for assessment of chemoradiotherapeutic response, whole volume measurements may be preferable. The panel acknowledges that several options exist but from a practical point of view decided to include tumour length as the main metric in the structured report template in Fig. 1, as this was deemed to be most commonly used and more practically applicable than other metrics, with good reported measurement reproducibility.<ref name="Beets-TanLambregts2017"/>
==== T-stage ====
* MRI doesn't differentiate T1 from T2<ref name="Beets-TanLambregts2017"/>*'''T1-T2: limited to intestinal wall'''<ref name="Beets-TanLambregts2017"/>*'''T3: extramural growth''' (including growth into the internal anal sphincter muscle)<ref name="Beets-TanLambregts2017"/>** '''T3a or T3b: ≤5 mm extramural growth'''<ref name="Beets-TanLambregts2017"/>** '''T3c or T3d: >5 mm extramural growth'''<ref name="Beets-TanLambregts2017"/>* '''T4'''<ref name="Beets-TanLambregts2017"/>
**T4a: Invasion of peritoneal reflection
**T4b: Invasion of surrounding organs
Observations:<ref name="Beets-TanLambregts2017"/>
* Stranding into mesorectal fat = equivocal sign; may indicate either a T2 or T3 tumour
==== Sphincter invasion ====
This information is relevant to surgical approachFor low tumours with sphincter invasion, describe:<ref name="Beets-TanLambregts2017"/>
For low tumours with sphincter invasion, describe:<ref name="Beets-TanLambregts2017"/> Depth of invasion<ref name="Beets-TanLambregts2017"/>
* invades only the internal sphincter muscle (T3)
* also involves the external sphincter
Height of invasion<ref name="Beets-TanLambregts2017"/>
* involves only the proximal 1/3 of the complex/anal canal
=== Mesorectal fascia (and peritoneal) involvement ===
* Shortest distance betwenn tumour and MRF<ref name="Beets-TanLambregts2017"/>
** Free (>2 mm)
** Threatened/involved (≤2 mm)
*Location of the shortest distance between tumour and MRF<ref name="Beets-TanLambregts2017"/>
* Tumour location in relation to anterior peritoneal reflection<ref name="Beets-TanLambregts2017"/>
** below: MRF invasion
** above: when on anterior side = at risk for peritoneal invasion (rather than MRF invasion)
Observations:<ref name="Beets-TanLambregts2017"/>
* The anterior peritoneal reflection is a landmark that is usually recognised easily on MRI and separates the intra- and extra-peritoneal portions of the mesorectal compartment. Above the anterior peritoneal reflection, the mesorectal compartment is no longer enveloped by the mesorectal fascia on its anterior aspect. As such, anterior mesorectal fascia involvement should only be reported when below the level of the anterior peritoneal reflection.
=== Lymph nodes and tumour deposits ===
* Important risk factor for local recurrence<ref name="Beets-TanLambregts2017"/>
* Assessment of extramural vascular (or venous) invasion (EMVI) should be reported routinely, both for primary staging as well as for restaging after CRT.<ref name="Beets-TanLambregts2017"/>* EMVI is an important prognostic staging factor<ref name="Beets-TanLambregts2017"/>
== Restaging after neoadjuvant treatment ==
* Structured reporting is recommended<ref name="Beets-TanLambregts2017"/>* When considering organ preservation (watchful waiting) after CRT, MRI findings should be correlated with clinical examination (endoscopy / digital rectal examination)<ref name="Beets-TanLambregts2017"/>
=== Local tumour status ===
T2W<ref name="Beets-TanLambregts2017"/>
* '''No residual tumour mass'''
**yT4, based on growth into:
* Distance from the anorectal junction to the lower pole of the tumour (in cm)<ref name="Beets-TanLambregts2017"/>* Tumour length (in cm)<ref name="Beets-TanLambregts2017"/>
For low tumours with sphincter invasion, describe:<ref name="Beets-TanLambregts2017"/>
Depth of invasion<ref name="Beets-TanLambregts2017"/>
* invades only the internal sphincter muscle
* also involves the external sphincter
Height of invasion<ref name="Beets-TanLambregts2017"/>
* involves only the proximal 1/3 of the complex/anal canal
=== Mesorectal fascia (and peritoneal) involvement ===
* If a fatpad re-appears between the tumour and MRF after CRT, the MRF should be considered uninvolved/cleared.<ref name="Beets-TanLambregts2017"/>* Persistent stranding of tumour into the MRF should be considered an equivocal sign that may or may not indicate persistent MRF involvement<ref name="Beets-TanLambregts2017"/>
=== Lymph nodes and tumour deposits ===
Restaging after long course neoadjuvant treatment + downstaging interval<ref name="Beets-TanLambregts2017"/>
* Benign nodes: Short axis diameter <5 mm
{{Bottom}}
<references />
Beets-Tan RGH, Lambregts DMJ, Maas M, et al. Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting [published correction appears in Eur Radiol. 2018 Jan 10;:]. Eur Radiol. 2018;28(4):1465–1475. doi:10.1007/s00330-017-5026-2