Esophageal Surgery

Define achalasia. What are the classic findings of esophageal achalasia?

Achalasia is a primary motility disorder of the esophagus characterized by a loss of enteric neurons leading to absence of peristaltic waveform in the body and impaired relaxation of the lower esophageal sphincter (LES) in response to swallowing. The condition is relatively rare, occurring at an incidence of 0.5 to 1 per 100,000 of the population per year, yet it is the most commonly diagnosed primary esophageal motility disorder. Peak incidence is between 20 and 50 years of age, and it typically has an insidious onset.

What are the most common symptoms of achalasia?

The nonrelaxing LES causes a functional outflow obstruction to the lower esophagus, resulting in progressive dysphagia, regurgitation, weight loss, and chest pain.

What is pseudoachalasia? How is it diagnosed?

Pseudoachalasia, or secondary achalasia, is an esophageal motility disorder caused by a distal esophageal obstruction from an infiltrating tumor that may directly intrinsically or extrinsically compress the esophagus Patients exhibit symptoms typical of achalasia, including dysphagia, regurgitation, chest pain, and weight loss. Conventional manometry, endoscopy, and radiologic examination cannot distinguish pseudoachalasia from achalasia. Endoscopy helps rule out the possibility of pseudoachalasia but cannot diagnose a mural or extramural tumor. When this is suspected, based on a history of substantial weight loss (more than 20 lb in 6 months), endoscopic ultrasonography or computed tomography is recommended. The main distinguishing feature is the complete reversal of pathologic motor phenomena following successful therapy of the underlying disorder.

What is vigorous achalasia?

Vigorous achalasia is a variant of achalasia in which the esophageal body responds to a swallow with normal or less often high-amplitude contractions that may be multiphasic, but as with classic achalasia, there are no progressive peristaltic waves. Patients with vigorous achalasia are usually younger and have chest pain as a prominent symptom. Additionally, in vigorous achalasia the LES pressure is higher and repetitive waves are more common than in classic achalasia. Most investigators believe that vigorous achalasia is an early form of the disease that presents in some patients.

What are the nonsurgical options for treatment of achalasia?

• Smooth muscle relaxants (nitrates, calcium channel blockers)

• Botulinum toxin

• Pneumatic dilatation of the LES

What are the basic components of laparoscopic Heller myotomy for achalasia?

Surgical treatment of achalasia consists of a longitudinal myotomy of the distal esophagus and gastroesophageal (GE) junction, first described by Ernest Heller in 1913. Most myotomies were performed through the chest before the advent of minimally invasive surgery. The transabdominal laparoscopic approach is currently the procedure of choice with good long-term results in 84% to 94% of patients.

Five trocars are placed in the upper abdomen in an arrangement similar to that of a laparoscopic antireflux operation. A myotomy roughly 6 to 8 cm in length is performed, 3 cm below the GE junction. The myotomy is carried down to the level of the mucosa. Intraoperative manometry is then used to confirm successful ablation of the pathologic high-pressure zone. A partial fundoplication is performed after the completion of the myotomy around a 52-Fr bougie. There is a general consensus that a complete 360-degree wrap may cause significant obstruction at the distal end of the esophagus and lead to worsening of esophageal function in patients with already impaired peristalsis. The Toupet fundoplication (partial posterior wrap) and Dor fundoplication (partial anterior wrap) are equally popular among surgeons. With the addition of a Dor antireflux wrap, the incidence of gastroesophageal reflux disease (GERD) decreases from 47.6% to 9.1%. A randomized trial compared Heller myotomy and Dor fundoplication with Heller myotomy and Nissen fundoplication; the recurrence rate in the Nissen group was significantly higher than the Dor group (15% vs. 2.8%, respectively) supporting the addition of Dor fundoplication to the Heller myotomy as the preferred method to prevent GERD. Patients with mild to moderate reflux after addition of a potential fundoplication can be easily managed medically.

How do long-term results of Heller myotomy compare with mechanical esophageal dilatation?

On the basis of excellent results with laparoscopic Heller myotomy, it is largely considered the optimal treatment for severe symptoms of achalasia. Several large retrospective series have compared the two treatments and favor operative myotomy over pneumatic dilatation. With the introduction of the minimally invasive approach, the historical concerns about the morbidity associated with open surgical techniques have essentially disappeared and the morbidity and mortality of both surgical and nonsurgical options are now nearly identical. The long-term success and safety of laparoscopic myotomy have completed the shift in favor of surgery as the primary therapeutic option for patients with achalasia. However, a recent randomized controlled trial that compared laparoscopic Heller myotomy (with Dor fundoplication added) with pneumatic dilatation revealed that the two techniques are equally effective in a 2-year follow up.

Describe the complications of Heller myotomy.

The most common complication of a surgical myotomy is esophageal perforation, which is reported in 0% to 4.6% of patients. Previous pneumatic dilatation and botulinum toxin injection increase the technical difficulty in performing a myotomy and may increase the rate of perforation. Mucosal injuries detected during surgery may be repaired primarily. An unrecognized esophageal perforation may present as persistent fever, tachycardia, or left-sided pleural effusion. These patients require close observation and may need reoperation if conservative measures fail.

Early postoperative dysphagia results usually from an incomplete myotomy, whereas causes of late dysphagia also include healing of the myotomy or, more rarely, a reflux-induced peptic stricture. Incomplete myotomy responds usually to extension of the myotomy. However, in patients in whom the first myotomy was complete, a second myotomy is less likely to be successful and such patients may require esophageal resection.

Summarize the treatment algorithm for patients with achalasia.

In summary, the treatment options for achalasia are initially medical (nitrates, calcium channel blockers), botulinum toxin injection, and pneumatic dilation. Surgical treatment (laparoscopic Heller myotomy, with Dor fundoplication) is reserved for patients with severe symptoms.

Patients who are unwilling to undergo any procedure should be treated with medications. Botulinum toxin injection should be reserved for patients who are unable to tolerate surgery because of significant comorbidities, or patients whose clinical presentation is complicated, putting the diagnosis of achalasia in doubt.

Overall, younger patients may choose early surgical intervention to avoid the need for multiple pneumatic dilatations. The decision for either of these two approaches will eventually be based on the medical specialist’s experience and the patient’s preference. Peroral endoscopic myotomy has also been gaining popularity as a means of treating achalasia.

What is the association between achalasia and esophageal cancer?

Patients with achalasia are thought to be at increased risk for the development of squamous cell carcinoma, with risk as high as 140-fold reported . The risk is elevated because of food retention, chronic chemical irritation, and bacterial growth, as well as the associated esophagitis and Barrett’s formation, the latter resulting in adenocarcinoma. Tumors develop at an age 10 years younger than in the general population and carry a worse prognosis because of late diagnosis. The effect of surgical treatment on the incidence of cancer is not known and surveillance endoscopy is recommended every 2 years .

What is the incidence of esophageal cancer?

Cancer of the esophagus accounts for 1% of all newly diagnosed cancers in the United States, and the incidence has continued to rise in the last 30 years. An estimated 13,000 new cases of carcinomas of the esophagus were diagnosed in men and 3500 new cases in women in 2009. Approximately 11,500 men and 3000 women will die from the disease. It is seven times more common in men than women and is the seventh leading cause of death from cancer among men. Whereas squamous cell carcinoma accounted for most cancers of the esophagus 40 years ago, adenocarcinoma now represents more than 70% of such tumors in the United States. This is primarily caused by the striking increase in incidence of adenocarcinoma among white men older than 60 years. The cause for the rising incidence and changing demographics is unknown, although part of the rise is due to the increasing incidence of Barrett’s esophagus and resulting adenocarcinoma in the distal esophagus.

What are the risk factors of esophageal cancer?

Risk factors for squamous cell carcinoma include tobacco use and excessive alcohol consumption, which appear to have a synergistic effect in its pathogenesis. Additionally, N-nitroso food compounds, achalasia, caustic injury, low socioeconomic status, and prior thoracic irradiation have been associated with an increased risk of the disease. Risk factors for the development of distal esophageal adenocarcinoma are less clear. The presence of Barrett’s esophagus is associated with an increased risk of developing adenocarcinoma, and recently a population-based case-control study from Sweden has demonstrated that symptomatic chronic GE reflux is also a risk factor.

Describe the relationship of Barrett’s esophagus to esophageal cancer.

Barrett’s columnar-lined esophagus is an acquired condition of the distal esophagus occurring in 10% to 15% of individuals with chronic GE reflux and in 6.8% of the general population. The incidence of adenocarcinoma increases nearly fortyfold in patients with Barrett’s esophagus. It is estimated that 5% of patients with Barrett’s esophagus will eventually develop invasive cancer , and patients with histologically proven Barrett’s esophagus require lifelong surveillance with endoscopic four-quadrant biopsies every 2 cm (1 cm if known dysplasia) because of this risk. It is also important that two different pathologists review the slides to increase the yield of the histologic diagnosis per the American Gastroenterological Association 2011 guidelines. It is generally believed that disease progresses from Barrett’s metaplasia to low-grade dysplasia to high-grade dysplasia (HGD) to adenocarcinoma.

Can Barrett’s esophagus regress after antireflux therapy?

Recent publications have suggested that curtailing reflux may decrease the tendency of GERD patients without Barrett’s epithelium to develop Barrett’s esophagus. In addition, reflux control may diminish the tendency toward dysplastic or malignant degeneration of existing Barrett’s epithelium. That can be accomplished by either medical or surgical management, with the latter shown to be more effective. This effect is manifested by:

• Inducing actual regression of dysplastic to nondysplastic Barrett’s epithelium

• Stabilizing the Barrett’s epithelium in a nondysplastic state

• Allowing a return to normal squamous epithelium

The majority of regression occurs within 5 years after surgery.

Discuss the surgical management of patients with HGD.

HGD is defined as the detection in the Barrett’s epithelium of epithelial abnormalities that could equally be described as carcinoma in situ (markedly enlarged nuclei at the surface, pronounced pleomorphism and focal loss of nuclear polarity). Many large surgical series document that following esophageal resection, between 20% and 40% of patients with Barrett’s esophagus who have severe dysplasia will be found to actually have invasive carcinoma in the specimen . Although this does not imply that the majority of the patients will have invasive carcinoma, the inability to reliably distinguish the two groups preoperatively means that every patient with HGD should be thought of as having a probable carcinoma. In addition, the likelihood of developing cancer in the first 3 to 5 years once severe dysplasia has been identified is 25% to 50%. This increases to 80% risk of adenocarcinoma development in 8 years. Therefore the finding of HGD is an extremely strong indication for surgical resection. Although there are recommendations for less invasive therapy modalities, as ablation (photodynamic therapy, cryotherapy, radiofrequency [RF] ablation) and endoscopic mucosal resection, the most definitive treatment is esophagectomy. The latter is challenged with increased morbidity and mortality rates. Recently minimally invasive approaches as vagal sparing esophagectomy have gained popularity for treatment of HGD to decrease the rates of morbidity and mortality associated with resection.

What are the surgical approaches to the patient with esophageal cancer?

Surgery is the primary treatment modality for esophageal cancer. In the United States, esophageal resection is most commonly performed, using one of the following approaches:

• Transhiatal esophagectomy involves both a midline laparotomy and left cervical incision. The short gastric and left gastric arteries are ligated, whereas the right gastric artery and right gastroepiploic arcade are carefully preserved to allow a well vascularized gastric conduit to reach to the neck. The esophagus is resected through the abdominal and neck incisions. A cervical GE anastomosis is performed through the cervical incision. The main advantage of this approach is avoidance of a thoracic anastomosis because a cervical leak carries much less morbidity than for a thoracic leak.

• Ivor-Lewis esophagectomy requires a midline laparotomy and a right posterolateral thoracotomy. En bloc resection is performed from the hiatus to the apex of the chest just above the azygos vein. A GE anastomosis is performed in the right chest.

• Multi-incision esophagectomy is performed less often and requires a midline laparotomy, right thoracotomy, and cervical incision.

• Left thoracoabdominal esophagectomy involves one incision extended across the abdomen and posterolateral chest for en block resection of the GE junction.

• Minimally invasive esophagectomy involves right thoracoscopic esophageal and lymph node bearing tissue mobilization, laparoscopic mobilization of the stomach, and a high intrathoracic or cervical anastomosis.

Regardless of the incision approach, the same operative procedure is performed, that is, esophagogastrectomy with regional lymph node resection. Although each approach has its proponents, transhiatal esophagectomy is the most common procedure performed, with a decreased incidence of pulmonary complications, the reduced morbidity and mortality of an anastomotic leak, and no evidence that a radical lymphadenectomy benefits overall survival cited as the most compelling arguments.

When is neoadjuvant therapy appropriate in the treatment of patients with esophageal carcinoma?

At most institutions, neoadjuvant treatment is currently recommended for stage III esophageal cancer or greater. There are different modalities of neoadjuvant therapy for esophageal cancer treatment, including either radiation alone (dose used 50 Gy), chemotherapy alone (chemotherapeutic agents used are cisplatin, 5-fluorouracil, carboplatin, paclitaxel, etoposide, or epirubicin), or chemoradiation prior to surgery. Preoperative radiation alone was found to have no significant benefit compared with surgery alone. Clinical trials have shown that neoadjuvant chemoradiation or chemoradiation were found to have statistically significant benefits for survival compared with surgery alone . Chemotherapy versus chemoradiation have been compared in clinical trials but no statistical difference was shown. Potential advantages of neoadjuvant therapy include cancer down-staging, increased resectability, and reduction in micrometastasis. In addition, the chemotherapeutic agents used all possess radiosensitizing properties. However, more studies are needed to verify the effectiveness of this treatment strategy.

Describe nonsurgical options for treatment of esophageal cancer.

Nonsurgical options for treatment of esophageal cancer can be divided into interventions for palliation and those for cure. Precancerous lesions or superficial cancers confined to the mucosa without evidence of metastatic spread can be cured with local therapy. Appropriate candidates include patients with limited HGD and carcinoma in situ associated with Barrett’s esophagus. In these cases, alternative therapies, such as endoscopic mucosal resection, endoscopically applied laser, photodynamic therapy, or argon plasma coagulation, are ablative therapies that have been curative in certain cases. When curative treatment is not possible, in addition to systemic chemotherapy, palliative care measures have included external beam radiation, endoluminal brachytherapy, endoluminal stenting, laser ablation, and photodynamic therapy.

What is the survival of patients with esophageal cancer?

The overall 5-year survival in patients with esophageal cancer is reported between 13% and 17%. Those patients with stage I disease have an excellent 5-year survival, approximately 80%. The 5-year survival for stage II and stage III disease is 20% to 30% and 10%, respectively. Those with stage IV disease live rarely beyond 18 months. Unfortunately, most esophageal cancers present at later stages with locally advanced disease or metastases, when cure is not possible and palliation is the only treatment option.