In the early 1980s, German scholar Buess first reported on Transanal Endoscopic Microsurgery (TEM, Transanal Endoscopic Microsurgery). Over the past decades, through the continuous application and innovation of colleagues in the medical field, as well as the continuous emergence of new technologies and equipment, TEM has developed rapidly and surgical techniques have become increasingly mature, and it has gradually become the first choice for colorectal surgical local resection.

For the surgical treatment of low rectal and anal canal tumors, clinicians have adopted the method of local resection through the anus very early. Although this method is simple, safe, less traumatic, and quick to recover, the lesions that it can handle are very limited, and are limited to the lower rectum and anal canal.

In traditional transanal resection, the surgical field of view is difficult to fully expose and the operation space is narrow, which greatly affects the completeness of surgical resection, resulting in a high rate of local recurrence of low intestinal tumors. 

With the advent of TEM technology, it is possible to direct access to the lesion with a slight injury, especially for mid-to-high rectal surgery that could not be done through the anus in the past.  Clinical practice has shown that TEM can be used for submucosal resection or full-thickness resection to radically treat early rectal cancer and rectal adenomas within 20 cm from the anal margin. The surgical wound can be sutured directly after the tumor is removed, and it can also complete the ring intestine. Segmental resection of cavity lesions and reconstruction of the digestive tract.

TEM provides a safe and effective method for the treatment of benign rectal adenoma and early rectal cancer. This minimally invasive surgery method combines the advantages of endoscopy, laparoscopy and microsurgery, has a lower complication rate and shorter postoperative hospital stay, and can avoid the implementation of enterostomy to the greatest extent. I believe that with the continuous improvement of surgical procedures by surgeons, TEM surgery will play a greater role in clinical practice.