Laparoscopic Lower Rectal Cancer Resection with Transanal Specimen Extraction (NOSES IA and NOSES IB)
NOSES I is mainly suitable for patients with small tumors located in the lower rectum. NOSES I has no differences regarding lymph node dissection or extent of resection when compared with the conventional laparoscopic radical resection of rectal cancer. The main differences distinguishing conventional laparoscopy and NOSES I are digestive tract reconstruction and specimen extraction. The main operating procedures of NOSES I include transanal specimen extraction, extraabdominal specimen removal, and totally laparoscopic anastomosis between the sigmoid colon and rectum. In addition, this technique may decrease positive lower tumor margin by allowing improved visualization of the relationship between inferior tumor edge and the dentate line. It may also improve the possibility of ultra-low anastomosis. At present, NOSES I includes two approaches of digestive tract reconstruction, namely, NOSES IA and NOSES IB. There are some slight differences between two approaches. NOSES IA involves the application of non-touch technique, but NOSES IB does not involve the non-touch technique. Therefore, the indication of NOSES IB is wider than NOSES IA. Both of the approaches show good radical effect, fast recovery, and favorable cosmetic results.