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Page 2 of 7 Kunkel et al. Mini-invasive Surg 2020;4:27 I http://dx.doi.org/10.20517/2574-1225.2020.05

Figure 1. Timeline depicting of the evolution of rectal cancer. APR: abdominoperineal resection; TEM: transanal endoscopic microsurgical;
TME: total mesorectal excision; TATA: transanal abdominal transanal; FTLE: full thickness local excision; SP: single port; NOTES: natural
orifice transluminal endoscopic surgery; TAMIS: transanal minimally invasive surgery; taTME: transanal total mesorectal excision; XRT:
radiation; ATA: abdominal transanal; IMA: inferior mesenteric artery

century. However, local recurrence (LR) rates of 20%-40% in the 1970s and 1980s and a desire to extend
[2]
sphincter preservation led to critical advances in rectal cancer management .

Improved operative approaches and high dose preoperative radiation were shown to reduce the rates of LR
[3]
[4]
in rectal cancers over the latter half of the 20th century . In 1982, Heald and Ryall sharpened the focus
on precision and proper surgical technique by performing meticulous dissection of the mesorectum and
formulating the term total mesorectal excision (TME). TME has since become a fundamental principle in
rectal cancer surgery and proved to reduce local recurrence rates.

[5]
Prior to this, in 1976, Mohiuddin et al. embarked upon the first program in the world that offered
sphincter preservation following high dose radiation therapy in the preoperative setting. It was quickly
realized that the irradiated rectal cancer was often so downstaged that sphincter preservation could
be expanded. A challenge existed in the diminished size, making the tumor difficult to reliably palpate
intraoperatively, hence leading to difficult determination of the distal tumor margin. To address these two
problems of extending sphincter preservation and assuring an adequate distal margin, a new operative
[6]
technique was conceived. In 1984, Marks et al. developed the transanal abdominal transanal (TATA)
proctosigmoidectomy with coloanal anastomosis. The operation commences by incising the rectum in a full
thickness fashion at the level of the dentate line and continuing the dissection cephalad. The rectal lumen
is oversewn in a watertight fashion. In this manner, a known distal margin to the tumor is established and
a total proctosigmoidectomy is then accomplished from an abdominal approach. This resection is followed
by a direct coloanal anastomosis using healthy, non-radiated tissue from the descending colon, and avoids
the need for a permanent colostomy. Contrary to the standard treatment of cancers in the distal third of
the rectum, which requires navigation through the narrow confines of the deep pelvis, the TATA procedure
avoids the need to apply a stapler from above. An underemphasized benefit of this approach is that the
most difficult part of the operation is carried out transanally, at the beginning of the operation. In addition
[7]
to preserving sphincter function, Marks et al. was able to reduce the local recurrence rate to 9% in a time
where local recurrence was reported to be 25%. The TATA procedure was shown to provide an oncologically
[7]
safe sphincter preserving procedure for patients that otherwise would have received an APR .