What is ESD?
Endoscopic treatments for early esophageal, gastric and colon cancers, and colon polyps have been widely performed using polypectomy and EMR (endoscopic mucosal resection) techniques, which are less invasive and more organ-sparing compared with abdominal surgeries. However, excision is performed using a looped operation tool called a "snare" which allows up to 2cm of lesion to be cut out at a time. Larger lesions have either been treated with abdominal surgeries or piecemeal removal using snare by which the lesions are sometimes left behind causing relapses and incorrect judgements of pathological examinations.
Recently, new endoscopic operation tools and machines have been developed in Japan enabling larger lesions to be removed en bloc. This is called ESD (Endoscopic Submucosal Dissection).
ESDIt can be said that ESD is a more secure method compared to conventional endoscopic treatments, enabling larger lesions to be excised en bloc, leaving nothing behind, eliminating the possibilities of relapses and allowing accurate judgments of pathological examinations.
Gastrointestinal cancers treatable by ESD
The wall of the gastrointestinal tracts consists of 3 layers. Cancers first appear at the surface of the most inner mucosal layer (1st layer) and invade through the submucosa (2nd layer) and then muscularis propria (3rd layer) as they grow larger.
- Esophageal cancer → Cancer invading the upper 2/3rds of the mucosal layer (Diagram 1)
- Gastric cancer → Existing only within the mucosal layer (1st layer) (Size is limited according to the types of cancers) (Diagram 2)
- Colon cancer → Assumable invasion of less than 1000μm（1mm）into the submucosa(2nd layer) (Diagram 3)
The above cases have no possibility of metastatis to other organs and can be completely cured without any abdominal operations using ESD. ESD can specifically dissect the submucosa (2nd layer) and higher, leaving the muscularis propria (3rd layer) intact.
How ESD treatments work
The procedure is done in several steps. First, the margins of the lesion are marked by electrocautery, and then a submucosal injection is used to lift the lesion (Diagram 4-8). After which, a circumferential incision into the submucosa is made around the lesion (Diagram 9). Finally, the lesion is dissected from underlying deep layers of GI tract wall with electrocautery knife and removed (Diagram 10-13). The lesion, mainly existing in the mucosal layer (1st layer), can be completely excised along with the submucosa (2nd layer)(Diagram 14-15).
Day ESD (Out-patient surgeries for early gastric cancer and colon cancer)
As ESD demands a sensitive touch in operation, it requires a high level of expertise and experience in GI endoscopy. Dr. Mitooka has successfully operated tens of thousands colonic tumors by the conventional method (polypectomy & EMR), and 315 cases (upper 165 cases (esophagus, stomach), lower 150 cases (colon)) by ESD (as of Dec. 2010) since 2003. Colonic ESD in particular, can be performed smoothly using the special endoscopy ´EC-450RD5/M´ which Dr. Mitooka and FUJIFILM cooperatively develop.
Perforation and hemorrhage are possible complications of ESD. Perforation can be prevented by attentive procedure and hemorrhage generally occurs in 3-5% of the stomach and only 1% in the colon, allowing ESD in an outpatient setting (day ESD) according to the size and the place of the lesions.
Dr. Mitooka has developed a novel and simple technique for the complete closure of large mucosal defects after ESD with hemoclips and fishing line using a conventional one-channel endoscope (up to 3cm in diameter for gastric specimens & 5cm in diameter for colonic specimens) allowing safer ESDs. ESD is a minimally invasive operation best suited for earliest stage of cancers and premalignant lesions, so that ESD in one day is possible. For those of you in need of ESD treatments and are busy, limited for time, or wish for a new treatment in one working day, please contact us.