The Surgeon's Perspective on Esophageal Disease, and What It Means to Pathologists
The Surgeon's Perspective on Esophageal Disease, and What It Means to Pathologists
Invasion beyond the muscularis mucosae is the defining transition point between endoscopic and surgical treatment of oesophageal adenocarcinoma. This is due to the increased risk of lymph node metastases beyond the submucosa. In fact, lymph node status is the only independent risk factor for survival and recurrence. While there is no consensus on the best surgical approach, it has been shown that tertiary high-volume centres experience better results with lower in-hospital mortality. For reference; the current American Joint Committee on Cancer 7th edition staging system for oesophageal cancer is shown in figure 4.
(Enlarge Image)
Figure 4.
7th edition American Joint Committee on Cancer TNM classifications. T is classified as Tis, high-grade dysplasia; T1, cancer invades laminal propria, muscularis mucosae, or submucosa; T2, cancer invades muscularis propria; T3, cancer invades adventitia; T4a, resectable cancer invades adjacent structures, such as pleura, pericardium, or diaphragm; T4b, unresectable cancer invades other adjacent structures such as aorta, vertebral body, or trachea. N is classified as N0, no regional lymph node metastasis; N1, regional lymph node metastases involving 1–2 nodes; N2, regional lymph node metastases involving 3–6 nodes; N3, regional lymph node metastases involving 7 or more nodes. M is classified as M0, no distant metastasis; M1, distant metastasis. Adapted from Rice and Blackstone [65].
There are several different types of oesophagectomy. Vagal-sparing oesophagectomy was developed for patients with intramucosal oesophageal cancer who did not need the extensive lymphadenopathy of a standard oesophagectomy. By avoiding the extensive lymph node dissection, the vagal nerves are spared and patients experience less gastrointestinal side effects, such as dumping and early satiety. The development of RFA and ER has largely supplanted this surgical technique, but it is still indicated in patients who require an oesophagectomy, but do not need an extensive lymph node dissection.
In patients with advanced locoregional tumours (invasion through the submucosa) extensive lymph node dissection should be performed. Our preferred surgical approach is the en bloc oesophagectomy. An en bloc oesophagectomy requires removal of the oesophagus and surrounding tissue as an en bloc specimen to maximise the number of lymph nodes removed. Some surgeons prefer an Ivor–Lewis approach which requires only two incisions (thoracic and abdominal), but our preference is a three-incision approach (right thoracotomy, laparotomy and cervical incision). This allows us to perform a cervical oesophago-gastrostomy. A right thoracotomy is performed first. This allows mobilisation and dissection of the oesophagus, division of the azygous vein and surrounding lymph nodes, ligation of the thoracic duct and a mediastinal lymphadenectomy (figure 5). This specimen is bordered laterally by mediastinal pleura, anteriorly by the pericardium and membranous trachea and posteriorly by the aorta and vertebral bodies. During dissection, both the right and left vagal nerves are sacrificed. Once the oesophagus and its surrounding tissue are sufficiently mobilised, the thoracotomy incision is closed and the patient is repositioned for the abdominal portion of the operation. A midline incision (laparotomy) is performed to allow dissection of the lymph node-bearing tissue surrounding the porta hepatis, retroperitoneal tissue overlying the pancreas and splenic artery, and the gastrocolic omentum. The gastroepiploic vascular arcade of the stomach is preserved and the short gastric vessels are divided near the splenic hilum. The coronary vein and the left gastric artery are ligated at their origin. The cervical oesophagus is then exposed in the neck through a surgical incision made along the anterior border of the left sternocleidomastoid muscle. The strap muscles of the neck are divided. A dissection plane is created between the carotid sheath laterally and the trachea medially to expose the oesophagus at the prevertebral fascia. The thoracic inlet is then developed, and the oesophagus is divided as low as possible. The oesophagus and tumour are passed inferiorly through the chest into the abdomen.
(Enlarge Image)
Figure 5.
(A) Ventral view of the mediastinum including the oesophagus (1), thoracic aorta (2) and trachea (3). (4) Right principal bronchus; (5) left principal bronchus; (6) bronchopulmonary LNs; (7) juxtaoesophageal pulmonary LNs; (8) inferior tracheobronchial LNs; (9) superior tracheobronchial LNs; (10) anterior mediastinal LNs; (11) thoracic duct. (B) Ventral view of the mediastinum included oesophagus (1) and thoracic aorta (2). (3) Brachiocephalic trunk; (4) left common carotid artery; (5) left subclavian artery; (6) anterior mediastinal LNs; (7) juxtaoesophageal pulmonary LNs; (8) prevertebral LNs; (9) anterior facies of the stomach; (10) coeliac trunk LNs; (11) gastric sinistri LNs; (12) pancreatico-colic LNs; (13) gastro-omental LNs. LNs, Lymph nodes. Adapted from Broering et al [66].
Trans-hiatal oesophagectomy was developed in order to minimise the morbidity of a thoracotomy. In this procedure, only a midline laparotomy and left neck incision are used. Through a laparotomy, lymph node dissection across the diaphragmatic hiatus is similar to the en bloc oesophagectomy. However, removal of the lower mediastinal lymph nodes is limited. Most of this operation is performed under direct vision through the widened oesophageal hiatus. The remainder of the upper oesophageal resection is carried out with blunt hand dissection. The vagal nerves are divided. Once the oesophagus is completely mobilised, the surgical specimen is removed and a cervical oesopahgo-gastrostomy is performed as described in the en bloc oesophagectomy section.
Once the oesophagus is removed by one of the three techniques described above (vagal sparing, trans-hiatal or en bloc oesophagectomy) reconstruction to re-establish continuity between the cervical oesophagus and the stomach is performed. A gastric tube is created using a linear stapler along the lesser curve of the stomach. The gastric blood supply is based on the right gastric and gastro-epiploic arteries (figure 6). Although, the gastric conduit is more commonly used due to its superior blood supply and ease of use, the colon and small bowel have also been used as an oesophageal replacement when the stomach is unavailable. Since vagotomy is performed, a pyloromytomy is done to promote gastric emptying. A feeding jejunostomy is indicated to allow enteral feeding in the early postoperative period while the surgical anastomoses are healing. Patients who have undergone oesophageal reconstruction, either with a gastric or colonic interposition, and who survive their cancer, do well long-term with good alimentary satisfaction and quality of life.
(Enlarge Image)
Figure 6.
Tubularised stomach. Note, the oesophagus must be resected at least 5 cm from the tumour-free margin. Adapted from Chernousov et al [67].
Oesophageal Adenocarcinoma
Invasion beyond the muscularis mucosae is the defining transition point between endoscopic and surgical treatment of oesophageal adenocarcinoma. This is due to the increased risk of lymph node metastases beyond the submucosa. In fact, lymph node status is the only independent risk factor for survival and recurrence. While there is no consensus on the best surgical approach, it has been shown that tertiary high-volume centres experience better results with lower in-hospital mortality. For reference; the current American Joint Committee on Cancer 7th edition staging system for oesophageal cancer is shown in figure 4.
(Enlarge Image)
Figure 4.
7th edition American Joint Committee on Cancer TNM classifications. T is classified as Tis, high-grade dysplasia; T1, cancer invades laminal propria, muscularis mucosae, or submucosa; T2, cancer invades muscularis propria; T3, cancer invades adventitia; T4a, resectable cancer invades adjacent structures, such as pleura, pericardium, or diaphragm; T4b, unresectable cancer invades other adjacent structures such as aorta, vertebral body, or trachea. N is classified as N0, no regional lymph node metastasis; N1, regional lymph node metastases involving 1–2 nodes; N2, regional lymph node metastases involving 3–6 nodes; N3, regional lymph node metastases involving 7 or more nodes. M is classified as M0, no distant metastasis; M1, distant metastasis. Adapted from Rice and Blackstone [65].
There are several different types of oesophagectomy. Vagal-sparing oesophagectomy was developed for patients with intramucosal oesophageal cancer who did not need the extensive lymphadenopathy of a standard oesophagectomy. By avoiding the extensive lymph node dissection, the vagal nerves are spared and patients experience less gastrointestinal side effects, such as dumping and early satiety. The development of RFA and ER has largely supplanted this surgical technique, but it is still indicated in patients who require an oesophagectomy, but do not need an extensive lymph node dissection.
In patients with advanced locoregional tumours (invasion through the submucosa) extensive lymph node dissection should be performed. Our preferred surgical approach is the en bloc oesophagectomy. An en bloc oesophagectomy requires removal of the oesophagus and surrounding tissue as an en bloc specimen to maximise the number of lymph nodes removed. Some surgeons prefer an Ivor–Lewis approach which requires only two incisions (thoracic and abdominal), but our preference is a three-incision approach (right thoracotomy, laparotomy and cervical incision). This allows us to perform a cervical oesophago-gastrostomy. A right thoracotomy is performed first. This allows mobilisation and dissection of the oesophagus, division of the azygous vein and surrounding lymph nodes, ligation of the thoracic duct and a mediastinal lymphadenectomy (figure 5). This specimen is bordered laterally by mediastinal pleura, anteriorly by the pericardium and membranous trachea and posteriorly by the aorta and vertebral bodies. During dissection, both the right and left vagal nerves are sacrificed. Once the oesophagus and its surrounding tissue are sufficiently mobilised, the thoracotomy incision is closed and the patient is repositioned for the abdominal portion of the operation. A midline incision (laparotomy) is performed to allow dissection of the lymph node-bearing tissue surrounding the porta hepatis, retroperitoneal tissue overlying the pancreas and splenic artery, and the gastrocolic omentum. The gastroepiploic vascular arcade of the stomach is preserved and the short gastric vessels are divided near the splenic hilum. The coronary vein and the left gastric artery are ligated at their origin. The cervical oesophagus is then exposed in the neck through a surgical incision made along the anterior border of the left sternocleidomastoid muscle. The strap muscles of the neck are divided. A dissection plane is created between the carotid sheath laterally and the trachea medially to expose the oesophagus at the prevertebral fascia. The thoracic inlet is then developed, and the oesophagus is divided as low as possible. The oesophagus and tumour are passed inferiorly through the chest into the abdomen.
(Enlarge Image)
Figure 5.
(A) Ventral view of the mediastinum including the oesophagus (1), thoracic aorta (2) and trachea (3). (4) Right principal bronchus; (5) left principal bronchus; (6) bronchopulmonary LNs; (7) juxtaoesophageal pulmonary LNs; (8) inferior tracheobronchial LNs; (9) superior tracheobronchial LNs; (10) anterior mediastinal LNs; (11) thoracic duct. (B) Ventral view of the mediastinum included oesophagus (1) and thoracic aorta (2). (3) Brachiocephalic trunk; (4) left common carotid artery; (5) left subclavian artery; (6) anterior mediastinal LNs; (7) juxtaoesophageal pulmonary LNs; (8) prevertebral LNs; (9) anterior facies of the stomach; (10) coeliac trunk LNs; (11) gastric sinistri LNs; (12) pancreatico-colic LNs; (13) gastro-omental LNs. LNs, Lymph nodes. Adapted from Broering et al [66].
Trans-hiatal oesophagectomy was developed in order to minimise the morbidity of a thoracotomy. In this procedure, only a midline laparotomy and left neck incision are used. Through a laparotomy, lymph node dissection across the diaphragmatic hiatus is similar to the en bloc oesophagectomy. However, removal of the lower mediastinal lymph nodes is limited. Most of this operation is performed under direct vision through the widened oesophageal hiatus. The remainder of the upper oesophageal resection is carried out with blunt hand dissection. The vagal nerves are divided. Once the oesophagus is completely mobilised, the surgical specimen is removed and a cervical oesopahgo-gastrostomy is performed as described in the en bloc oesophagectomy section.
Once the oesophagus is removed by one of the three techniques described above (vagal sparing, trans-hiatal or en bloc oesophagectomy) reconstruction to re-establish continuity between the cervical oesophagus and the stomach is performed. A gastric tube is created using a linear stapler along the lesser curve of the stomach. The gastric blood supply is based on the right gastric and gastro-epiploic arteries (figure 6). Although, the gastric conduit is more commonly used due to its superior blood supply and ease of use, the colon and small bowel have also been used as an oesophageal replacement when the stomach is unavailable. Since vagotomy is performed, a pyloromytomy is done to promote gastric emptying. A feeding jejunostomy is indicated to allow enteral feeding in the early postoperative period while the surgical anastomoses are healing. Patients who have undergone oesophageal reconstruction, either with a gastric or colonic interposition, and who survive their cancer, do well long-term with good alimentary satisfaction and quality of life.
(Enlarge Image)
Figure 6.
Tubularised stomach. Note, the oesophagus must be resected at least 5 cm from the tumour-free margin. Adapted from Chernousov et al [67].
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