INTRODUCTION AND DEFINITION
Carcinoma of the esophagus is a growing problem in the United States, where an estimated 16,470 new cases and 14,755 deaths were predicted for 2008. Eighty percent of primary tumors of the esophagus are malignant. Histology includes squamous cell carcinoma, adenocarcinoma, anaplastic small cell (oat cell) carcinoma, adenoid cystic carcinoma, carcinosarcoma, lymphoma, leiomyosarcoma, and melanoma ( Table 56-1 ). The most common esophageal cancer worldwide is squamous cell carcinoma, especially in certain endemic areas such as Asia, eastern and southern Africa, and the Middle East. The most common histology in the nonendemic areas, especially the United States, is adenocarcinoma. Adenocarcinoma accounts for more than 50% of esophageal malignancies, and the incidence is rising; the rate of the second highest esophageal malignancy, squamous cell carcinoma, is steadily decreasing. In the United States, carcinoma of the esophagus is the seventh leading cause of cancer death in men.
Histology | Incidence in the United States |
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A. Primary Tumors | |
Adenocarcinoma | >95% |
Squamous cell carcinoma | |
B. Unusual Primary Tumors | |
Adenocarcinoma variants | |
Adenoid cystic carcinoma (cylindroma) | |
Mucoepidermoid carcinoma | |
Adenoacanthoma | |
Choriocarcinoma | |
Squamous cell variants | |
Verrucous carcinoma | |
Polypoid carcinoma (pseudosarcoma) | |
Small cell carcinoma | |
Melanoma | |
Lymphoma | 1–2% |
Mesenchymal Tumors | |
Leiomyosarcoma | |
Rhabdomyosarcoma | |
Fibrosarcoma | |
Chondrosarcoma | |
Osteosarcoma | |
Liposarcoma | |
Kaposi’s sarcoma | |
C. Secondary Tumors | |
Metastatic cancer | |
Breast, lung, stomach |
ETIOLOGY
There are clear and numerous risk factors for squamous cell carcinoma and only a few identifiable risk factors for adenocarcinoma.
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Squamous cell carcinoma: Most commonly occurs in the proximal two thirds of the esophagus.
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Carcinogens:
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Nitrosamines:
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Associated with cured meats and pickled foods.
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Tobacco
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Nutritional factors
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Alcohol
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Vitamin Deficiencies
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Anemia
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Previous gastric surgery
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Premalignant lesion
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Leukoplakia
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Previous head and neck malignancy
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Previous external beam irradiation
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Injury or chronic irritation
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A result of chronic stasis injury
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Achalasia
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Esophageal diverticula
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Plummer-Vinson syndrome
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Chronic irritation
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Ingestion of hot foods and beverages
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Caustic burn injury
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Adenocarcinoma: Smoking and obesity are thought to be risk factors for adenocarcinoma. Barrett’s metaplasia and gastroesophageal reflux disease (GERD) are clear risk factors. Adenocarcinoma most commonly occurs in the distal two thirds of the esophagus.
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GERD
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GERD causes Barrett’s metaplasia. In a nationwide Swedish case-controlled study, patients with long-term symptomatic GERD had a 43 times increased risk of developing adenocarcinoma of the esophagus compared with asymptomatic controls.
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Barrett’s metaplasia
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Characterized by the change of nonkeratinizing stratified squamous esophageal epithelium to gastric or intestinal type columnar epithelium with goblet cells, beginning at the esophagogastric junction (EGJ) and extending proximally.
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Barrett’s metaplasia leads to a 30 to 40 times increased risk of developing adenocarcinoma.
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Barrett’s metaplasia should be suspected when a patient with long-standing heartburn has resolution of his or her symptoms. Barrett’s metaplasia is an acid-insensitive lesion.
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All patients with Barrett’s metaplasia should undergo an indefinite surveillance program.
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Adenocarcinoma occurs in 2% of all patients with Barrett’s metaplasia without dysplasia, 7% of patients with low-grade dysplasia, and 22% of patients with high-grade dysplasia.
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Surveillance program consists of flexible endoscopy every 2 years, with brushings and four quadrant biopsies every 2 cm of involved mucosa.
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On endoscopy, Barrett’s metaplasia appears as salmon-colored tonguelike projections into normal-appearing mucosa ( Fig. 56-1 ).
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CLINICAL FEATURES
Symptoms and Signs
Most patients with carcinoma of the esophagus present with dysphagia. Dysphagia may start with solids and progresses to liquids. Patient can often point to the exact site of their obstruction.
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Other symptoms include
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Weight loss
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Odynophagia
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Chronic anemia from a friable lesion
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Hematemesis
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Recurrent pneumonias
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From aspiration or a malignant tracheoesophageal fistula
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Hoarseness
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From direct invasion of the recurrent laryngeal nerve.
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Horner’s syndrome.
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Invasion of the stellate ganglia.
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DIAGNOSIS
The diagnosis of esophageal cancer can be made in 95% of patients using a combination of barium swallow and flexible endoscopy with brushings for cytology and biopsy of suspicious lesions. Barium swallow may identify strictures or other filling defects ( Fig. 56-2 ). Flexible endoscopy may identify malignant-appearing strictures or fungating, ulcerative, or infiltrative masses ( Fig. 56-3 ).
STAGING
The TNM classification of the American Joint Committee of Cancer ( Table 56-2 ) is used to define staging of carcinoma of the esophagus, where T is depth of tumor penetration, N is lymph node involvement and M is nonregional nodal and distant organ metastasis. At the time of diagnosis, 50% of patients have disease that has advanced beyond locoregional limits, and 80% of resected specimens have regional lymph node metastasis.
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Tumor depth of penetration (T)
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T1 lesions invade through the lamina propria into the submucosa.
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T2 lesions infiltrate the muscularis propria.
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T3 lesions grow into the surrounding adventitia.
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T4 lesions grow into surrounding structures such as the carina and pericardium.
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Lymph node involvement (N)
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EGJ lymph nodes are left gastric, subcarinal, and intrathoracic paraesophageal lymph nodes.
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For intra-abdominal esophageal tumors, celiac nodes can be swept with the specimen.
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Intrathoracic esophageal regional lymph nodes are subcarinal and intrathoracic paraesophageal nodes.
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Cervical esophageal regional lymph nodes are the internal jugular, scalene and cervical paraesophageal lymph nodes.
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Metastatic disease (M)
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M1a refers to nonregional nodal metastasis. M1a staging for upper thoracic esophageal tumors are the cervical lymph nodes. M1a staging for lower thoracic esophageal tumors are the celiac axis lymph nodes. M1a staging for midthoracic esophageal tumors are nonapplicable because nonregional nodal metastasis carries the same prognosis as distant (M1b) metastasis.
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Staging imaging studies: Important staging studies must include chest and abdominal computed tomography (CT) scan with oral and intravenous contrast, endoscopic ultrasound (EUS), and positron emission tomography (PET) with 18F-deoxyglucose (FDG).
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CT scan
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Useful for defining the locoregional spread of the primary tumor, invasion of adjacent structures, and distant organ metastasis.
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EUS with fine-needle aspiration (FNA)
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Study of choice for determining T stage of primary tumor.
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EUS also identifies regional lymph nodes, which can be biopsied by FNA.
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Biopsy of nodes near the primary tumor may lead to false-positive results.
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Five sonographic layers corresponding to the mucosa (first two layers), submucosa, muscularis propria, and the adventitia.
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Tumors and lymph nodes appear as hypoechoic lesions.
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Combined CT and EUS demonstrate an accuracy of 79% for staging the primary tumor and 82% for staging regional lymph nodes.
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PET scan
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Useful in staging nodal metastasis and distant organ metastasis.
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PET has a sensitivity of 78% for detecting distant nodal and other metastatic disease.
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Primary Tumor (T) | |
TX: | Primary tumor cannot be assessed |
T0: | No evidence of primary tumor |
Tis: | Carcinoma in situ |
T1: | Tumor invades lamina propria or submucosa |
T2: | Tumor invades muscularis propria |
T3: | Tumor invades adventitia |
T4: | Tumor invades adjacent structures |
Regional Lymph Nodes (N) | |
NX: | Regional lymph nodes cannot be assessed |
N0: | No regional lymph node metastasis |
N1: | Regional lymph node metastasis |
Distant Metastasis (M) | |
MX: | Distant metastasis cannot be assessed |
M0: | No distant metastasis |
M1: | Distant metastasis |
Tumors of the lower thoracic esophagus | |
M1a: Metastasis in the celiac lymph nodes | |
M1b: Other distant metastasis | |
Tumors of the midthoracic esophagus | |
M1a: Not applicable | |
M1b: Nonregional lymph nodes and/or other distant metastasis | |
Tumors of the upper thoracic esophagus | |
M1a: Metastasis in cervical nodes | |
M1b: Other distant metastasis | |
Stage | |
0 | TisN0M0 |
1 | T1N0M0 |
IIA | T2N0M0 |
T3N0M0 | |
IIB | T2N2M0 |
T3N1M0 | |
III | T3N1M0 |
T4AnyNM0 |