TaTME	Transanal total mesorectal excision
APE	Abdominoperineal extirpation
AR	Anterior resection
R1	Microscopic presence of tumor cells at the distal or circumferential resection margins or within a lymph node < 1 mm from the mesorectal fascia of the excised specimen
CRM [+]	Circumferential resection margin of the excised specimen [presence of tumor cells within 1 mm from the excised non-peritonealised surface of the rectum]
DRM [+]	Distal resection margin of the excised specimen [presence of tumor cells within 1 mm from the excised distal end of the specimen]
Quality of TME specimen	Using the Quirke grading system for completeness of mesorectal dissection, each TME specimen is graded as having either an intact mesorectum, minor or major defects.17
TNM-stage	Classification of colorectal carcinoma (tumor, lymph nodes, metastasis)
ARJ	Anorectal junction (located approximately 3 cm proximal from AV)
AV	Anal valve
EMVI	Extra-mural vascular invasion (sign seen on MRI-imaging)
Clavien–Dindo classification	Ranking classification of postoperative complications, based on the therapy used for that specific complication
1	Any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic and radiological interventions
2	Requiring pharmacological treatment with drugs other than such allowed for grade I complications
3a	Requiring surgical, endoscopic or radiological intervention not under general anesthesia
3b	Requiring surgical, endoscopic or radiological intervention under general anesthesia
4	Life-threatening complication requiring IC/ICU-management
5	Death of a patient

Source http://www.assessurgery.com/clavien-dindo-classification/