Description

Transanal Endoscopic Microsurgery (TEM) is a minimally invasive surgical technique developed for the precise removal of rectal lesions. Introduced in the 1980s by Professor Gerhard Buess in Germany, TEM has since become an established procedure for the management of selected benign and early-stage malignant rectal tumors. Unlike conventional open or radical rectal surgery, TEM allows access to the rectum through the anal canal, eliminating the need for abdominal incisions. Principle and Technique TEM uses a specially designed rectoscope, approximately 40 mm in diameter, which provides an enlarged and stable view of the rectum. A stereoscopic binocular system ensures magnified visualization, while long, fine surgical instruments allow for delicate dissection and excision. Carbon dioxide insufflation maintains rectal distension, creating a controlled working space. The procedure enables: Full-thickness excision of rectal lesions Accurate suturing of the rectal wall Minimal trauma to surrounding tissues Indications TEM is particularly beneficial for: Benign rectal polyps not amenable to conventional endoscopic removal Early-stage rectal cancers (T1 lesions without lymph node involvement) Selected T2 lesions in patients unfit for radical surgery Local excision in high-risk patients where major surgery poses significant risks Advantages of TEM Compared with open or radical rectal surgery, TEM offers numerous advantages: Minimally invasive approach with no abdominal incision Lower morbidity and complication rates Shorter hospital stay and faster recovery Better functional outcomes with preservation of anal continence Oncological safety in carefully selected cases Limitations Despite its advantages, TEM is not suitable for all patients. Its limitations include: Restricted indication for advanced rectal cancers requiring lymphadenectomy High equipment and training requirements Steep learning curve for surgeons Potential complications such as bleeding, rectal perforation, and strictures (though rare) Outcomes Numerous studies have shown TEM to be effective, with low recurrence rates for benign lesions and acceptable oncological outcomes in early cancers when proper selection criteria are applied. The procedure has significantly reduced the need for radical resection in many cases, thus preserving quality of life for patients. Future Perspectives With technological advancements, TEM is evolving into newer techniques such as Transanal Minimally Invasive Surgery (TAMIS), which uses single-port laparoscopic devices. These innovations are further simplifying transanal surgery, expanding access, and reducing equipment costs. Conclusion Transanal Endoscopic Microsurgery (TEM) represents a landmark advancement in colorectal surgery, bridging the gap between conventional endoscopy and radical resection. By providing precise local excision with minimal invasiveness, TEM offers patients faster recovery, fewer complications, and excellent functional outcomes—making it an important tool in the armamentarium of colorectal surgeons worldwide.