Endoscopy has increased the detection of early neoplastic lesions of the gastrointestinal tract (GIT) known as gastrointestinal superficial lesions.
Endoscopic resection is adequate in patients with early gastrointestinal cancer with limited or completely nil submucosal involvement. Endoscopic resections are mainly used for high- and low-grade dysplasia. Most lesions can be treated using endoscopic mucosal resection (EMR), however unsuitable for lesions greater than 20mm in size. Endoscopic submucosal dissection (ESD) allows to achieve an ‘en bloc’ resection of the lesions, irrespective of the size of the tumor.
Endoscopic resection is indicated for esophageal cancers with no risk of lymph node invasion. The size of the lesion is the main criterion for the choice of the procedure.
Barrett’s esophagus: EMR is the gold standard for endoscopic excision in Barrett’s esophagus; the main limitation is piecemeal resection with EMR, which makes histopathological assessment difficult, and the risk of recurrence and residual tumor is high. ESD should be considered for lesions greater than 15mm, poorly lifting tumors, and those at risk for submucosal invasion.
The lesions which should be considered for endoscopic resection because of a very low risk of lymph node metastasis are the following:
- non-invasive neoplasia (dysplasia) independently of size;
- intramucosal differentiated-type adenocarcinoma, without ulceration (size ≤2cm absolute indication, >2cm expanded indication);
- intramucosal differentiated-type adenocarcinoma, with ulcer, size ≤3cm (expanded indication);
- intramucosal undifferentiated-type adenocarcinoma, size ≤2cm (expanded indication);
- differentiated-type adenocarcinoma with superficial submucosal invasion.
EMR was the first treatment alternative to surgery for early gastric cancer. However, EMR is associated with a high recurrence rate (30%) according to some studies.
ESD for early gastric cancers has higher ‘en bloc’ resection rates, histologically complete resection rates, and low recurrence rates. ESD though is associated with longer operative times.
The use of endoscopic resection in the duodenum and the small bowel is limited because of a high risk of perforations. EMR standard or piecemeal resections can be used for superficial lesions with perforation rates less than 5%.
EMR represents a highly effective treatment for lesions of the colon less than 20mm in diameter. Piecemeal EMR for larger lesions reduces the quality and reliability of histopathological findings.
In the rectum, the indications for ESD may be extended for all large (>20mm), non-granular (NG) or granular lesions, or mixed laterally spreading tumors (LSTs) (>20-30mm).
ESD can be considered for the removal of colonic and rectal lesions with a high suspicion of limited submucosal invasion, which is based on two main criteria, namely a depressed morphology and an irregular or non-granular surface pattern, particularly if the lesions are larger than 20 mm.
EMR should be the first option for the following:
- superficial lesion in Barrett’s esophagus;
- small gastric lesion