Esophageal Intervention in Malignant and Benign Esophageal Disease

Benign Esophageal Strictures

Benign strictures of the esophagus occur as the result of collagen deposition and fibrous tissue formation stimulated by esophageal injury. Peptic strictures, caused by esophageal exposure to gastric acid, account for 70% to 75% of benign esophageal strictures. Other common causes of benign strictures include Schatzki ring, ingestion of corrosive agents (including certain medications), external-beam radiation therapy, sclerotherapy, photodynamic therapy, reaction to a foreign body, infectious esophagitis, and surgical trauma.

Corrosive Strictures

Corrosive strictures can be either diffuse or local. With diffuse corrosive strictures, strong alkali or strong acid (if the concentration, volume, and duration of contact are sufficient) can lead to necrosis, which may be deep and extend over a considerable area, sometimes leading to perforation. Within 3 weeks, fibrous scarring develops and leads to stricture formation, which is graded as follows:

• • Grade I: shelf strictures involving a short segment but not circumferential

  • Grade II: annular strictures less than 1 cm in length

  • Grade III: dense annular strictures less than 1 cm long extended through all layers

  • Grade IV: tubular strictures with periesophageal adhesions

Various tablets cause esophagitis locally if they adhere to the mucosa. This sometimes progresses to local stricture formation by fibrous scarring. Local strictures after corrosive tablet ingestion are usually short and not dense. They are easily dilated and may require only one course of bougienage or balloon dilation. Strictures caused by liquid corrosives may be more difficult to manage and are dealt with according to their grade. Grades I, II, and most of III can be treated by intermittent dilation, beginning 3 weeks after the injury. Dilation carried out earlier often leads to perforation. Initially, weekly dilations are necessary, but the treatment interval can be gradually prolonged if there is a good response. Tough grade III strictures and most long grade IV strictures may be difficult and hazardous to dilate, and as a result surgery may be necessary.

Achalasia

Achalasia is an esophageal motor disorder characterized by increased lower esophageal sphincter (LES) pressure, diminished to absent peristalsis in the distal portion of the esophagus, and lack of a coordinated LES relaxation in response to swallowing.

Primary achalasia is the most common subtype and is associated with loss of ganglion cells in the esophageal myenteric plexus. These important inhibitory neurons induce LES relaxation and coordinate proximal-to-distal peristaltic contraction of the esophagus. LES pressure and relaxation are regulated by excitatory (e.g., acetylcholine, substance P) and inhibitory (e.g., nitric oxide, vasoactive intestinal peptide) neurotransmitters. Patients with achalasia have an imbalance in excitatory and inhibitory neurotransmission. The result is a hypertensive, nonrelaxing esophageal sphincter.

Secondary achalasia, which is relatively uncommon, is caused by conditions other than intrinsic disease of the esophageal myenteric plexus, such as certain malignancies, diabetes mellitus, and Chagas disease.

Epidermolysis Bullosa

Epidermolysis bullosa (EB) is a very rare skin fragility disorder characterized by blister formation after minor mechanical trauma. The clinical subset varies from only mild skin reactions to severe, mutilating deformities such as pseudosyndactyly and fatal forms, depending on the genotypic subtype of the disease. In severe types, gastrointestinal, urologic, and corneal abnormalities have been also noted. In general, two major categories are recognized: inherited (IEB) and acquisita (EBA). The inherited type is more common and can be divided into four principal types: EB simplex, dystrophic EB, junctional EB, and Kindler syndrome. It is calculated that IEB affects 1 to 3 births in every 100,000 live births; nearly 5,000 patients in the United Kingdom suffer from the disease. EBA is an autoimmune primary blistering disease associated with immunoglobulin G autoantibodies against type VII collagen, the basal membrane zone of the skin and the malpighian mucosa. Collagen VII is a major component of esophageal epithelium, so high-grade esophageal strictures resulting in severe dysphagia and malnutrition are noted in various EB subtypes. Esophageal involvement is more frequent in the recessive dystrophic EB subtype; almost 70% of these patients will develop at least one esophageal stricture by the age of 25.

Esophageal Varices

Esophageal varices detected before the first hemorrhage are usually treated with oral β-adrenergic blocking agents. If varices are of a high endoscopic grade, sclerotherapy or variceal ligation may be performed. In the setting of acute esophageal variceal hemorrhage, control of bleeding can be accomplished endoscopically in 80% to 90% of patients. Radiologic interventions employed in the treatment of esophageal varices include transjugular intrahepatic portocaval shunt, embolization of the varices, or both.

Esophageal Strictures in Children

Esophageal strictures occur in 40% of children after surgical repair of esophageal atresia. The main causes are fibrosis subsequent to natural healing, size difference of the two anastomosed segments, tension, and gastroesophageal reflux. Leaks, as well as use of a two-layer anastomosis and/or silk sutures, increase the likelihood of stricture formation. Dilation is 90% effective, but strictures that do not respond to repeated dilation can be treated by temporary stenting—a technique still under evaluation—or by repeated surgery.

Esophageal atresia is a condition in which the proximal and distal portions of the esophagus do not communicate. The upper segment of the esophagus is a dilated blind-ending pouch with a hypertrophied muscular wall. This pouch typically extends to the level of the second to fourth thoracic vertebrae. The distal esophageal portion has a small diameter and a thin muscular wall; it extends a variable distance above the diaphragm.

Tracheoesophageal fistula is an abnormal communication between the trachea and esophagus. When associated with esophageal atresia, the fistula most commonly occurs between the distal esophageal segment and the trachea, just above the carina.

The frequency and severity of complications after repair of esophageal atresia are related to the extent of the repair required, with primary anastomosis and fistula closure being associated with fewer complications than esophageal replacement. The most common complications are anastomotic leak, recurrent fistula, stricture, and gastroesophageal reflux.

Malignant Esophageal Strictures

The main indications for esophageal stenting in malignant disease are as follows:

• • Intrinsic esophageal obstruction

  • Tracheoesophageal fistula. Spontaneous malignant fistulas between the esophagus and major airways occur as a result of local tumor invasion from the esophagus or tracheobronchial tree ( Fig. 88.1 ) or may be secondary to surgery or esophageal stent placement. Esophageal leaks or perforations are usually iatrogenic after esophageal dilation or surgery, but may also be caused by local tumor invasion. Leaks and fistulas in benign disease should not be stented because leakage occurs around the stent. In many such cases there is spontaneous healing. However, without definitive treatment malignant lesions will not heal, and most patients die of malnutrition and thoracic sepsis within weeks. Until recently, therapy for malignant leaks and fistulas has been unsatisfactory. Attempted surgical repair has a high morbidity and mortality. Parenteral nutrition or feeding via gastrostomy may be used, but continuing leakage of esophageal contents results in mediastinitis in many patients. Attempts to seal the esophageal defect with plastic stents have historically been ineffective. Covered self-expanding metallic stents are the first treatment of choice in patients with malignant leaks and fistulas because the metallic stent expands to the diameter of the esophagus and the covering material seals the defect.

    

  • Extrinsic esophageal compression by primary or secondary mediastinal tumors

  • Esophageal perforation, usually iatrogenic, from direct endoscopic trauma or after stricture dilation

  • Symptomatic gastroesophageal anastomotic leaks

  • Anastomotic tumor recurrence after surgery

Materials and Equipment

• Water-soluble nonionic contrast medium

• Tilting fluoroscopic table

• Monitoring equipment (pulse oximeter, blood pressure, and pulse measurement)

• Suction equipment

• Oxygen

• Radiopaque ruler

• Lidocaine spray

• Mouth guard

Catheters and Guidewires

• Biliary manipulation catheter

• Multipurpose 6F, 100-cm catheter

• 0.035-inch Bentson guidewire

• 0.035-inch hydrophilic wire (Terumo Medical Corp., Somerset, NJ)

• 260-cm, 0.035-inch stiff exchange wire

Balloons

• 14- and 18-mm diameter (MediTech/Boston Scientific, Natick, MA), 30- and 40-mm balloons (Rigiflex [Boston Scientific])