**1. Introduction**

#### **1.1. History**

Wolff and Shinya published their experience with *therapeutic* colonoscopy in September 1969 in JAMA [2], three months after they had commenced to perform diagnostic fiber colonoscopy. Since then, this has become an increasingly significant arm of minimally invasive colorectal surgery, complementing, even possibly replacing procedures that were once performed using "open" surgical techniques. [1-3]

Following the introduction of the fiber-optic colonoscopy for diagnostic evaluation of the lower gastrointestinal tract, enabling all parts of the colon to the assessed under direct vision and instrumentation as reported by Deyhle and Demling in 1971, and Sakai in 1972, [4-5] mastery of these techniques by Williams and colleagues have enabled therapeutic interven‐ tions to be performed endoscopically. [6]

Propelling this "endoscopic therapy" movement is the increasing evidence of the "adenomacarcinoma" polyp-cancer sequence introduced by Morson and Bussey from 1968 to 1970. [7] This fundamental concept has enabled a form of prevention of colorectal cancer by endoscopic removal of precursor lesions and is the basis of colonoscopic screening for colorectal cancer, resulting in the effective cessation to their progression to cancer.
