Endoscopic Submucosal Dissection (ESD)

Endoscopic Submucosal Dissection (ESD) is an advanced, minimally invasive endoscopic procedure used to excise early-stage tumours or complex precancerous lesions of the oesophageal lining. Although traditional surgical procedures may include removing a portion of the oesophagus, ESD allows doctors to excise diseased tissue through the inner lining using an endoscope. The time spent on recovery is also minimised because the procedure preserves the organ's normal swallowing function and reduces damage.

This article will discuss the clinical benefits of ESD, the technical accuracy of the dissection procedure, and a comprehensive standard of care at Gleneagles Hospitals to ensure optimal therapeutic outcomes.

The oesophagus has several layers: the innermost mucosa is covered by the middle submucosa, and the outer layer is covered by the muscular layer. The oesophageal cancer is not metastatic but usually starts in the mucosa at an early stage. If the disease involves the submucosa but has not reached the deep muscle, ESD may be a suitable treatment strategy.

ESD is a more advanced version of endoscopic resection. During the procedure, a professional uses a flexible endoscope with a high-quality camera and microscopic surgical blades. In contrast to less advanced resection techniques, ESD involves a comprehensive dissection of submucosal tissue. This allows the doctor to remove a large area of diseased tissue in a single "en bloc" (all at once) specimen. It is important that the tumour is removed intact so pathologists can assess the margins accurately.

ESD is critical in the early detection and treatment of oesophageal cancer, particularly when the disease is confined to the mucosa or superficial submucosa.

The primary goal of the treatment during this stage is to eliminate the tumour without injuring the oesophagus. ESD does this by providing a focused treatment in which there is no necessity to undergo a pivotal operation like oesophagectomy.

The process is particularly useful in the case when:

• The tumour is localised and small.
• No signs of severe invasion of the muscular layer.
• Spread to lymph nodes is low.

Endoscopic Submucosal Dissection (ESD) can be utilised as a medical treatment in well-selected individuals. It can also help to avoid more invasive treatments and their associated risks.

The process typically lasts one to three hours, depending on the size and complexity of the lesion.

• Mapping: The doctor uses specialist dyes or high-definition images to identify the exact borders of the cancer.
• Lifting: A sterile fluid is injected into the submucosal layer. This pushes the cancer away from the underlying muscle, allowing for a safe dissection.
• Cutting: The doctor uses an electrosurgical knife to cut through the mucosa around the tumour.
• Dissection: The physician carefully separates the submucosal fibres, gradually removing the cancerous tissue along with the submucosal layer beneath it.
• Retrieval: The lesion is extracted intact and sent to the laboratory for a thorough microscopic analysis.

Since ESD does not involve any external chest or abdominal incisions, the post-surgical approach is significantly less aggressive than traditional oesophageal surgery.

• Inpatient Observation: Patients are often kept in the hospital for one to two nights. This allows the nursing team to monitor for any signs of bleeding and ensure that the patient is safe to swallow.
• Pain Management: The majority of patients have moderate pain or a sore throat, which is easily treated with ordinary medications.
• Dietary Progression: The doctor recommends a certain dietary plan. To ensure the treated area is fully healed, the patient usually starts with clear liquids and progresses to soft foods around the first week of therapy.
• Healing Monitoring: The oesophageal lining begins to regenerate almost immediately. An endoscopic follow-up is usually performed after a few months to ensure that the region has healed with normal tissue.

Endoscopic Submucosal Dissection has several significant benefits to patients with diagnosed oesophageal cancer, in the early stage.

• Higher Cure Rates: Cure rates are higher because the tumour is resected as one piece, and this technique achieves a higher rate of complete resection (so-called R0), with no cancer cells remaining along the margins.
• Organ Preservation: This process also aids in preserving the oesophagus, which is critical, as it prevents long-term digestive and nutritional complications commonly experienced post-esophagectomy.
• Reduced Complications: The risks of wound infections, lung complications, and cardiac strain are considerably lower than with traditional open surgery.
• Accurate Pathology: The intact sample allows pathologists to report the most exact stage of cancer, which is crucial in planning future care.

Although specialised centres, such as Gleneagles Hospitals, have a very low risk of complications during the ESD procedure, the medical team explains the possible risks to each patient.

• Delayed Bleeding: The resection site may experience mild bleeding. It is usually managed immediately during the procedure, using a thermal probe or a metal clip.
• Perforation: A small tear can be created due to the dissection around the muscle layer. Surgery is not usually necessary, as small perforations can often be closed immediately using endoscopic clips.
• Stricture Formation: When a significant percentage of the oesophageal circumference is removed, scar tissue may result in constriction (stricture) during the healing process. If it occurs, it is addressed with simple endoscopic dilation.

At Gleneagles Hospitals, they provide an exclusive facility to perform interventional endoscopy, and that includes:

• Experienced Endoscopists: Doctors who have been trained in advanced techniques of submucosal dissection.
• Advanced Technology: The presence of the existing types of electrosurgical knives and the Narrow Band Imaging (NBI) to map tumours.
• Multidisciplinary Team: Close collaboration between the pathologists, oncologists and surgeons to offer successful cancer care.
• Comprehensive Care: A focus on patient comfort, from pre-operative education to long-term follow-up and monitoring.