Magnetic resonance imaging in rectal cancer: A surgeon’s perspective

Table 4 Post long course chemoradiotherapy magnetic resonance imaging 2-Parameters are assessed on post treatment magnetic resonance images

	Pre treatment	Post treatment
Height of tumor from anal verge
Length of tumor
Tumor stage (sub stage based on extramural spread)
Nodal spread
Nodes pelvic sidewall
Involvement peritoneal reflection
Distance to potential CRM
Depth of maximum extramural spread (distance from outer edge of muscularis propria) tumor and fibrosis separately
Extramural venous invasion

MRI tumor regression grade, Grade V: No response (same as original tumor); Grade IV: Slight response (litte area of fibrosis/mucin, mostly tumor); Grade III: Moderate response (more than 50% fibrosis, mucin but mostly tumor); Grade II: Good response (dense fibrosis, no obvious residual tumor); Grade I: Radiological complete response (no evidence of ever treated tumor); CRM: Circumferential resection margin.