Total mesorectal excision (TME)--twenty years on

Area of Science:

• Colorectal Surgery
• Surgical Oncology
• Oncology

Background:

• Total mesorectal excision (TME) principles for rectal cancer were established 20 years ago.
• Superior outcomes were initially linked to complete mesorectal excision, preference for anterior resection, use of cytotoxic solutions, and surgical specialization.
• A review examines 20 years of evidence supporting these TME tenets.

Purpose of the Study:

• To review and evaluate the evidence supporting the key principles of total mesorectal excision (TME) for rectal cancer over the past two decades.
• To assess the role of mesorectal metastases, surgical technique variations, adjuvant therapies, and surgeon specialization in rectal cancer outcomes.

Main Methods:

• A comprehensive Medline search was conducted.
• Studies focused on mesorectal metastases, anterior resection vs. abdominoperineal resection, exfoliated tumor cells, and rectal cancer surgery specialization were included.

Main Results:

• Mesorectal metastases (up to 5 cm from tumor) are present in pT3/pT4 tumors, indicating poorer prognosis.
• TME improves outcomes in mid/low rectal cancers; its role in upper rectal/rectosigmoid cancers is debated.
• Anterior resection superiority over abdominoperineal resection is not definitively proven; cytotoxic irrigation may reduce anastomotic recurrence; specialized rectal cancer surgery lowers morbidity, mortality, and recurrence rates while increasing sphincter preservation.

Conclusions:

• The foundational principles of total mesorectal excision (TME) proposed 20 years ago are largely supported by subsequent research.
• Evidence confirms the importance of complete mesorectal excision, specialized surgical practice, and potentially adjuvant measures in improving rectal cancer outcomes.