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Locally extensive but nonmetastatic cancers of the upper aerodigestive tract on occasion may require resection. Tumors of the larynx, cervical trachea, hypopharynx, cervical esophagus, and thyroid can be exenterated with a pharyngolaryngotracheoesophagectomy as primary therapy. It also can be used as salvage after failed primary therapy, treatment of locally recurrent tumor, treatment of benign complications of successful primary therapy, or long-term palliation. The enormity of these procedures is overshadowed by the likely possibility of limited survival, the potential for significant complications, and the expected negative impact on quality of life. However, in curatively resected and properly reconstructed patients, the long-lasting effects are little more than those experienced by the laryngectomy patient. |
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PREOPERATIVE EVALUATION AND PREPARATION Distant metastatic disease is excluded by PET/CT and disease-specific imaging (e.g., thyroid scanning for differentiated thyroid cancers). Regional nodal metastases are frequently detected by physical examination and confirmed by cytologic evaluation of fine-needle aspiration specimens. However, cervical ultrasonography may be necessary to better examine and determine regional nodal status. Local extent of the primary tumor is critical in deciding resectability but frequently is underestimated by preoperative testing. Regardless, local invasion should be evaluated in particular to identify carotid, vertebral body, and mediastinal involvement. This may require multiple imaging modalities (e.g., angiography, MRI, fine-cut CT scanning, barium esophagram, and bone scan). The proximal and distal extents of the tumor are assessed by oropharyngoscopy, bronchoscopy, and esophagoscopy (i.e., panendoscopy). These endoscopic procedures are accompanied by appropriate biopsy of the tumor and its margins. The skin and subcutaneous tissue that overlie and are in the vicinity of the primary tumor must be examined to exclude malignant invasion or severe radiation damage, if radiation was administered previously. The reconstruction must be planned and prospective organs of replacement and reconstruction evaluated. Vascular insufficiency secondary to smoking or accelerated atherosclerosis may necessitate angiographic assessment of these organs and tissues. Gastroscopy and colonoscopy are essential to exclude intrinsic disease if the stomach or colon is being contemplated for replacement. The tissue planned for pedicled or free flaps must be assessed and alternatives considered and evaluated. A mediastinal tracheostomy may be necessary for reconstruction if there is a significant length of tracheal involvement. This may require division of the innominate artery to avoid postoperative arterial erosion and ensuing hemorrhagic complications. Therefore, angiographic assessment of the cerebral blood supply and patency of the circle of Willis is mandatory if mediastinal tracheostomy and division of the innominate artery are planned. As in all patients undergoing airway and esophageal surgery, cardiopulmonary assessment is essential. Comorbidities must be evaluated and managed optimally preoperatively. During this time, the nutritional status and fitness of the patient are maximized. |
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THE OPERATION Preparation and Positioning The patient is placed in the supine position. Arterial line, oxygen saturation probe, and venous catheter placements are guided by the possibility of division of the innominate artery and sacrifice of the left innominate vein. Similarly, electrocardiographic pad placement may be affected by the resection of the primary tumor or harvesting of reconstructive flaps. Electroencephalographic leads may be placed for monitoring if there is concern about resection compromising cerebral perfusion. Techniques and equipment necessary for endotracheal intubation will be determined by the primary tumor and the presence of an established tracheostomy. Provisions must be made for cross-table ventilation during surgery. The operative field is prepared and draped from the chin to the suprapubic abdomen and lateral to the midaxillary line bilaterally. The thigh and arm and forearm may be included in the field if they are to be used for flap harvesting or skin grafting. Exploration The operation starts with a collar incision placed above the sternal notch and positioned such that it may be extended, if necessary, laterally over the clavicles and inferiorly over the manubrium (Fig. 58-1). If a tracheostomy exists, the stoma should be included in the incision. Invaded or radiation-damaged skin is excluded from the flaps, excised, and left attached to the tumor. The superior subcutaneous flap is raised above the hyoid bone; the inferior flap is lifted up to the sternal notch. Superior invasion and invasion of the mediastinum are assessed during this mobilization. If uninvolved, the strap muscles are separated in the midline. If invaded, they are divided and left attached to the primary tumor. Lateral dissection determines if the carotid sheath is involved by the tumor. The prevertebral space is developed to ensure that the resection can be completed posteriorly. These steps confirm tumor resectability, and to this point, no irreversible steps have been taken.
Resection The resection begins inferiorly. If a mediastinal tracheostomy is necessary, the incision is extended in the midline inferiorly over the manubrium. Lateral myocutaneous flaps are raised off the bony chest wall, and the manubrium is excised along with the first and second cartilages and the clavicular heads (breastplate). The level of tracheal division is selected. The trachea is mobilized circumferentially at this site, and lateral dissection is restricted below this point. Lateral traction sutures are placed in the tracheal wall one cartilage below the anticipated position of the tracheal transection (Fig. 58-2). These sutures stabilize the trachea and facilitate tracheal intubation during cross-field ventilation. Once the trachea has been divided and distal intubation obtained, the tracheal margin is sent for frozen-section analysis. Some thyroid and airway tumors (e.g., adenoid cystic carcinoma) may not involve or may minimally invade the esophagus, permitting esophageal preservation without compromising the resection. In patients requiring cervical exenteration, the point of esophageal transection is determined. The extent of the primary tumor and the method and organ of esophageal reconstruction will dictate this level. If a free flap is being used for reconstruction, the esophagus is divided in the low neck, and this margin is sent for frozen-section analysis.
The dissection proceeds superiorly. The prevertebral plane already assessed is now easily developed. Laterally, the dissection is carried along the carotid sheaths. Rarely, unilateral sacrifice of the internal jugular vein is required. If unilateral carotid excision is necessary, arterial reconstruction will be needed. If the thyroid is not involved, the isthmus is split, and one or both sides are preserved and allowed to remain in the lateral resection margins. If not radiated, this practice preserves thyroid and parathyroid function. If possible, resected parathyroid tissue that is uninvolved with primary tumor may be autotransplanted and this position marked with radiopaque clips. The superior margin of the resection is now defined. The superior border of the hyoid bone is cleared of the attachment of the mylohyoid, geniohyoid, and genioglossus muscles. Lateral muscular attachments of the larynx are divided, and the superior laryngeal neurovascular bundle is controlled and divided (Fig. 58-3). The pharynx is entered anteriorly, and the superior resection proceeds posteriorly. The epiglottis is incorporated in the resection specimen. The superior resection margin is sent for frozen-section analysis.
Reconstruction There are two main methods of pharyngoesophageal reconstruction, using either gastrointestinal transposition (i.e., stomach or colon) or microvascular free flaps (i.e., jejunum or myocutaneous). The general approach is to use gastric or colonic transposition for tumors that extend to or below the thoracic inlet and free flaps for short-length reconstructions above the thoracic inlet.1–3 However, in any one institution, the experience may be so small that one of these methods may become the reconstruction of choice. If division of the trachea is well above the sternal notch, a cervical tracheostomy stoma can be constructed. However, if tracheal division is at or below the sternal notch, or if the operation is performed for tracheal stomal recurrence, a mediastinal tracheostomy will be necessary.4,5 The anterior breastplate is excised. Erosion of the innominate artery, a major complication of mediastinal tracheostomy, can be avoided by separating the tracheal stoma from the innominate artery. If the stoma will be positioned immediately adjacent to the artery, elective division and oversewing of the ends under electroencephalographic monitoring has been reported.6However, transposing the trachea below and to the right of the innominate artery also has been used successfully to avoid this dreaded complication.7 Division of the innominate artery must be placed proximal to the carotid-subclavian bifurcation. The omentum can be used to cover anastomoses, separate innominate artery stumps, and for tracheal wrapping below the stoma.8 If there is significant soft tissue resection and wound closure is problematic, a benefit of using myocutaneous free flaps is the ability to reconstruct both gastrointestinal and soft tissue defects with the flap.9–11 |
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POSTOPERATIVE MANAGEMENT ICU care is mandatory in the initial postoperative management of cervical exenteration patients. Mechanical ventilation usually is required. A customized tracheostomy tube may be necessary for the shortened trachea in patients requiring mediastinal tracheostomy. Trauma to the tracheal stoma should be avoided by careful and secure stabilization of the tracheostomy tube. A low-pressure tracheostomy cuff will protect the edematous and potentially ischemic trachea from necrosis and stricture. Adequate humidification of the inspired air-oxygen mixture is important to minimizing pulmonary complications. Vigorous chest physiotherapy and careful pulmonary/tracheostomy care are the major focus of early postoperative care. A nasogastric tube is necessary in patients with gastric reconstruction of the pharyngoesophageal segment, who are very susceptible to regurgitation. Nutrition is provided via feeding tubes or parenterally until gastrointestinal function returns and the pharyngoesophageal replacement has healed. Regardless of parathyroid preservation during resection, careful monitoring of serum calcium and prompt management of postoperative hypocalcemia are required in all patients. The need for long-term thyroid hormone replacement should be assessed. |
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SPECIFIC COMPLICATIONS AND RESULTS A common site of complications specific to cervical exenteration is the gastrointestinal anastomosis. Varying degrees of anastomotic disruption can occur. The problem may be as simple as a transient anastomotic leak that can be managed by placing the patient on nothing by mouth, providing enteral or parenteral nutrition, and locally draining the area. In the extreme case, there can be graft necrosis necessitating removal of the reconstruction, creating a pharyngostomy, oversewing of the distal gastrointestinal tract, and constructing a feeding gastrostomy or jejunostomy. Anastomotic strictures usually are managed by repeated dilation. Universally, patients with gastric reconstruction are subject to regurgitation with coughing, reclining, or bending over. This is the result of sacrifice of the upper esophageal sphincter and the high pharyngeal location of the anastomosis. With time and specific maneuvers, such as limiting the size of meals and remaining upright for 2–3 hours after eating, this problem can be tolerated. However, this predictable functional disorder has led some to favor the colon over the stomach for gastrointestinal reconstruction after cervical exenteration. Tracheal stomal separation usually is treated conservatively, responding to debridement. Stomal stenosis can be managed with long-term placement of an indwelling tracheostomy tube. Recalcitrant stenosis will require revision of the tracheostomy and possibly conversion of a low cervical tracheostomy to a mediastinal tracheostomy. Vascular complications are common to mediastinal tracheostomy unless the steps mentioned earlier are taken to separate the stoma from the innominate artery. Cerebrovascular accidents not necessarily related to innominate artery division can complicate this extensive resection. Chylous leakage may complicate extensive dissection around the left subclavian-internal jugular veins. Conservative management using parenteral nutrition and local drainage may not be successful because of the exenteration. Reexploration with direct ligation of the lymphatic injury or thoracotomy with ligation of the thoracic duct has been used. However, there is increasing experience with the use of lymphangiography and x-ray-guided percutaneous embolization of the thoracic duct. Hepatic failure has complicated the postoperative course of patients with squamous cell carcinoma undergoing cervical exenteration. Alcohol abuse, a factor in the development of these cancers, may cause clinically unsuspected cirrhosis that is uncovered in the recovery from this extensive surgery. Pulmonary complications are a common problem in the postoperative course of these patients. Long-term survival is determined by the underlying cancer. |
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SUMMARY Cancers of the upper aerodigestive tract on occasion may require resection, typically for salvage after failed primary treatment or long-term palliation. Preoperative evaluation and operative exploration determine resectability. An en bloc pharyngolaryngotracheoesophagectomy necessitates (1) reconstruction of the pharynx and esophagus (using gastric or colonic transposition for tumors that extend to or below the thoracic inlet and free flaps for short-length reconstructions above the thoracic inlet and esophagus) and (2) a permanent end tracheostomy. Specific complications include (1) varying degrees of gastrointestinal anastomotic disruption and (2) hemorrhage common to mediastinal tracheostomy unless steps are taken to separate the tracheal stoma from the innominate artery. Long-term survival after cervical exenteration is determined by the underlying cancer. |
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CASE HISTORY A 65-year-old man, a retired army veteran, presented with solid dysphagia and a lump in his left neck. He was found to have a T4aN1M0 squamous cell carcinoma of the hypopharynx with invasion of the esophagus and a single 2-cm ipsilateral regional nodal metastasis. Before therapy, he stopped smoking and reduced his drinking to two glasses of beer a day. He received definitive chemoradiotherapy, three courses of cisplatin (100 mg/m2) and concurrent external beam radiation (72 Gy). His posttreatment course was complicated by dysphagia, which responded to two sessions of guided esophageal dilation. He did well for 14 months, when he again experienced difficulty swallowing solids and new onset of hoarseness. He was found to have recurrence of squamous cell carcinoma in the anterior wall of the hypopharynx and left vocal cord paralysis. Clinical examination and imaging suggested that this was a local recurrence. The patient underwent a pharyngolaryngotracheoesophagectomy (Fig. 58-4). A total esophagectomy was necessary because of involvement of the cervical esophagus and an associated radiation stricture. A pharyngogastric anastomosis was constructed with a single-layer interrupted absorbable suture. The tracheostomy was placed low in his neck, just above the sternal notch. An omentum graft was brought substernally to cover the pharyngoesophageal reconstruction and wrap the trachea at the stoma. The patient's postoperative course was complicated by respiratory compromise and a pharyngocutaneous anastomotic fistula. Vigorous chest physiotherapy, frequent suctioning, broad-spectrum antibiotics, meticulous care of his tracheostomy stoma, and 3 weeks of mechanical ventilation were necessary for successful treatment of his postoperative pneumonia. Local drainage of the fistula, nasogastric tube drainage of his stomach, and nutritional support via his J-tube successfully closed the anastomotic fistula in 4 months.
Four years after cervical exenteration, the patient is swallowing well. His tracheostomy stoma is well healed and requires only daily tracheostomy care. By physical examination, there is no local recurrence of his hypopharyngeal carcinoma. Imaging had been performed at 6-month intervals; however, he missed his last CT scan. He has been found to have a 2-cm spiculated mass in the upper lobe of his right lung. This was hypermetabolic on FDG-PET examination (standard uptake value (SUV) 7.3) with no evidence of regional lymph node enlargement or hypermetabolism. Fine-needle aspiration proved this to be a squamous cell carcinoma. He is presently receiving radiosurgery for this presumed metachronous primary squamous cell carcinoma of the lung. |
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EDITOR'S COMMENT Most proximal esophageal tumors can be successfully handled with chemotherapy and radiation therapy. However, recurrence in fit individuals can be managed with aggressive resection as described in this chapter. Given a presumed normal thoracic esophagus, this type of case is safely managed with a transhiatal esophagectomy. The gastric conduit can usually be made to reach the base of the tongue. –RB |
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