Gastroenterology and Hepatology – Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection
Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection for the Safe and Effective Removal of Cancerous or Potentially Cancerous Lesions from the Gastrointestinal Tract
With advances in endoscopic equipment and techniques, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have become established treatments for the safe and effective removal of mucosal lesions of the esophagus, stomach, duodenum and colon. The effective resection of these lesions allows for the endoscopic cure and/or definitive staging of gastrointestinal, mucosal, neoplastic lesions in these respective organs. EMR and ESD are now routinely performed at many large volume referral medical centers such as Penn State Health Milton S. Hershey Medical Center and have changed the management of these lesions throughout the gastrointestinal tract by allowing effective resection without the need for major surgery. Indications for EMR and ESD include:
- Mucosal lesions of the esophagus (cancerous or potentially cancerous) including nodules or masses within Barrett’s Esophagus and short segment Barrett’s Esophagus with dysplasia.
- Gastric mucosal lesions.
- Duodenal lesions, including ampullary lesions requiring ERCP assisted ampullectomy.
- Adenomatous colon and rectal lesions which are not amendable to safe or complete removal during a screening a colonoscopy.
- Limited gastric and rectal carcinoid tumors.
- In highly selected cases, submucosal tumors may be resected by EMR or ESD with good results.
These procedures are highly effective and should result in endoscopic cure in amenable and properly staged lesions. Cure can be expected in a high percentage of cancerous lesions in the upper GI tract which have a stage of T1a and less (cancerous tissue does not invade through the muscularis mucosa). The criteria for endoscopic curative treatment of colon and rectal lesions has recently been proposed to be expanded to include lesions with limited submucosal invasion without certain high risk features.* However, any cancer with more advanced or high risk features should be managed in a multidisciplinary fashion in conjunction with surgical and medical specialist, radiologists, and pathologists as is the case at Milton S. Hershey Medical Center. More advanced lesions should be effective staged, and should receive consideration of more aggressive treatments, such as major surgery.
A variety of techniques are used in EMR for complete removal of lesions depending on the nature of the tumor and its location. Typically at Milton S. Hershey Medical Center, injection of an EMR cocktail of either normal saline or hydroxy propyl methylcellulose with dilute epinephrine and methylene blue is used to separate the lesions from the important muscularis propria, allowing better visualization and prevention of entrapment or damage to the muscularis propria by separating it from the resection plane and any thermal or mechanical injury which could occur. ESD is a more aggressive technique using recently available tools to perform a dissection through the submucosal dissection plane and removing an entire lesion en block. This allows a thorough resection of larger flat lesions with more definitive histological assessments and lesion removal. However, this method is more technically demanding and time consuming with a slightly increased rate of complications. However, ESD is considered in select cases at Milton S. Hershey Medical Center where en block or a deeper resection is required.
The benefits of EMR and ESD outweigh the risks when performed in a high volume center with an appropriate team including skilled interventional endoscopists who have the correct equipment and procedure volume, such as Milton S. Hershey Medical Center. However, complications can occur and should be explained to the patient when considering these options. Complications include bleeding which occurs in 5-10% of cases.** Sixty-five percent of these bleeding episodes will occur within 24 hours of EMR, and patients may be kept for that period of time for observation at Milton S. Hershey Medical Center. Perforation has been known to occur in approximately 1% of EMR procedures and approximately 2-5% of cases for ESD. The estimated rates of lesion recurrence after EMR is estimated at 1 to 11%, and is felt to be less in ESD.*** In order to prevent incomplete EMR and ESD, it is important for referring physicians to know that previous failed attempts at lesion removal using electrocautery will increase the technical difficulty of EMR and increase the risk of incomplete lesion removal and/or complications. If a lesion is identified during a screening procedure and is not felt to be appropriate for complete removal during the screening procedure, it is best to leave the lesion alone, mark it appropriately, and consider biopsy of the periphery (if histological confirmation is required) and then refer for EMR or ESD.
In order to assure abnormal tissue is not been left behind, patients will be brought back in 3-6 months for a repeat colonoscopy and possible argon photo ablation of any abnormal tissue that has been left behind. If necessary, an early surveillance colonoscopy will be done in one year’s time. At that point, the patients will typically be referred back to their referral physicians to reenter a routine surveillance program. Referral physician should feel free to call the office for discussion and any referral for this procedure can easily be done using the Open Access Form which is available by calling 717-531-8364. This form should be accompanied by the original procedure report and/or pathology report from the outside institution.
* Journal of Gastroenterology and Hepatology 27 (2012) page 1057-1062.
** Metz, et al. Endoscopy, 2011.
***Endoscopy, 2011 November (43): page 941