Pathophysiology

Esophageal cancers are usually related to squamous cell carcinoma or adenocarcinoma.⁶ The majority of esophageal tumors are located in the lower third of the esophagus (55%), but one tenth are found in the upper esophagus and these are usually squamous cell carcinomas.⁶ Esophageal adenocarcinomas arise in Barrett esophagus, a metaplasia of the distal esophagus occurring in association with long-term gastroesophageal reflux.⁶ The extensive lymphatic system of the esophagus allows cancers of the esophagus to spread locally and into adjacent mediastinal structures regardless of tumor type.⁷

Clinical Presentation

Dysphagia is the classic presenting symptom of esophageal carcinoma. This symptom indicates that the esophageal lumen has been reduced by at least half of its normal diameter.⁸ Other symptoms include anorexia, weight loss, and odynophagia with radiation to the back. Hoarseness results from tumor involvement of the recurrent laryngeal nerve, and a tracheoesophageal fistula may produce a chronic cough.⁸ The clinical features of esophageal adenocarcinoma are similar to those of squamous cell carcinoma, but it may also produce early satiety, nausea, vomiting, and bloating because of tumor encroachment into the stomach.

Physical Examination

Fixed supraclavicular, cervical, and axillary lymphadenopathies are signs of advanced disease. Both hepatomegaly secondary to metastatic disease and superior vena cava syndrome indicate a poor prognosis.^7,8

Diagnostics

New-onset dysphagia should prompt an evaluation for an esophageal tumor. Diagnostic evaluation of the patient with a suspected esophageal carcinoma is a two-step procedure that begins with barium esophagography and is followed by upper gastrointestinal endoscopy with biopsy and cytologic tests.⁵ Barium esophagography and endoscopy are used in evaluating the primary tumor. Endoscopic ultrasound examination will help determine the extent of disease locally.⁵ A clinical examination, biochemical assay, chest x-ray examination, computed tomography (CT) scan, positron emission tomography–computed tomography (PET/CT) scan, radionuclide bone scan, ultrasonography, and guided fine-needle aspiration biopsy of lymph nodes may be useful in the evaluation of metastasis.⁵

Differential Diagnosis

In the adult patient with a new onset of progressive, solid dysphagia, the differential diagnosis includes esophageal squamous cell carcinoma, esophageal adenocarcinoma, adenocarcinoma of the gastric cardia, benign peptic stricture, corrosive stricture, and esophageal motor disorders such as achalasia and scleroderma. Symptoms of dysphagia, especially in a patient older than 45 years, mandate a complete evaluation to exclude esophageal carcinoma.

Gastroenterologic, oncologic, and surgical consultations are critical for the evaluation of esophageal tumors. Surgical resection is the primary treatment of early-stage esophageal cancer. Chemotherapy with cisplatin and 5-fluorouracil plus radiation therapy with or without surgery may provide the best potential for cure in locally advanced disease.⁷ However, palliation for dysphagia may be the only realistic goal because most patients have incurable disease at the time of diagnosis. Palliation can be accomplished by peroral stenting through the stenosis and transendoscopic ablation of obstructing tumors by laser photocoagulation.

For advanced disease, esophagectomy provides superb palliation.⁹ Radiotherapy may provide palliation for patients who are not candidates for surgery.⁹

Systemic chemotherapy is a preferred method of palliation for metastatic disease. There are many chemotherapy agents available; however, there is not one particular regimen that is standard of care in the first-line setting.

Postoperative elevation of serum carcinoembryonic antigen (CEA) levels may be the first objective sign of recurrent disease and should prompt additional therapy, such as surgery or chemotherapy.¹⁰

Complications

Because of the distensibility of the esophagus, esophageal carcinoma tends to be silent until late in its course. Complications are usually related to mediastinal extension or esophageal narrowing and may include obstruction, hemorrhage, perforation, and fistula formation. Because the esophagus lacks a true serosa, cancer is often not contained at the time of diagnosis. The lungs and liver are the most common sites of hematogenous metastasis. Complications of esophageal resection include torsion or gangrene of the gastric, colonic, or jejunal pull-up; anastomotic leak; anastomotic stricture; subphrenic abscess; chylothorax; hemorrhage; wound infection and dehiscence; sepsis; dumping syndrome; vocal chord paralysis, and reflux esophagitis.

Patient and Family Education

Dietary instructions should be consistent with the degree of dysphagia experienced. Patients who have responded to therapy but continue to use alcohol and tobacco products during treatment demonstrate a poor response to treatment and an increased rate of local recurrence.⁹ Therefore, patients should be encouraged to discontinue the use of these products and should be provided with therapeutic interventions for alcohol and tobacco cessation.^9,11

Health Promotion

Patients should be regularly questioned about the presence of heartburn or other signs of gastroesophageal reflux so that appropriate diagnostics and treatment can be initiated. Primary prevention of esophageal cancer includes avoidance of all tobacco products and of heavy alcohol consumption. It is also important to consume a diet that is rich in fruits and vegetables and to maintain a normal weight. With obesity, there can be increased acid reflux, thus multiplying the risk for adenocarcinoma of the lower esophagus and stomach.^9,11

Pathophysiology

Gastric cancer is divided into two histologic types, intestinal and diffuse.⁵ The intestinal type of gastric adenocarcinoma is characterized by distinct, large glands lined by columnar cells; it resembles intestinal cancer and is more common than the diffuse type.⁵ The diffuse type of gastric cancer is poorly differentiated, lacks a glandular structure, and is more aggressive.⁵ Gastric carcinomas spread by direct extension, lymphatic spread, hematogenous metastasis, and peritoneal seeding.

Clinical Presentation

Unexplained weight loss, upper abdominal pain, anorexia, nausea, and vomiting are the most common symptoms of advanced gastric carcinoma.⁴ The abdominal pain begins as insidious upper abdominal discomfort that ranges in intensity from a vague sense of postprandial fullness to a severe, steady pain. Other symptoms include change in bowel habits, dysphagia, melena, anemic symptoms, and hemorrhage.⁴

Physical Examination

Patients with advanced gastric cancer may be initially seen with cachexia, small bowel obstruction, epigastric mass, ascites, hepatomegaly, or lower extremity edema. Metastases may also manifest as an enlarged left supraclavicular lymph node (Virchow node) or an enlarged left anterior axillary lymph node, an enlarged periumbilical lymph node (Sister Mary Joseph node), an enlarged ovary (Krukenberg tumor), or a mass on the Blumer shelf on rectal examination.⁵

Diagnostics

Blood studies may reveal hypochromic, microcytic anemia secondary to iron deficiency. The stool is often positive for occult blood. Upper gastrointestinal endoscopy is the imaging modality of choice for stomach tumors because it allows direct visualization and biopsy of the tumor.⁵ Once the diagnosis of gastric cancer is confirmed, abdominal and chest CT scans along with endoscopic ultrasound examination are indicated to establish the invasiveness of the primary tumor and the extent of metastasis.⁵

Differential Diagnosis

The differential diagnosis for tumors of the stomach includes gastric lymphoma; leiomyosarcoma; carcinoid tumors; and gastric metastasis from the lung, breast, and melanoma. Kaposi’s sarcoma of the stomach, which may be present in patients with acquired immunodeficiency syndrome (AIDS), and hypertrophic gastropathy (Meniere disease) are also included in the differential diagnosis.

Management

Gastroenterologic, surgical, and oncologic consultations are essential for a patient with gastric cancer. Complete resection of the gastric carcinoma and adjacent lymph nodes offers the only chance for cure. A palliative resection should be considered for patients with advanced lesions who are initially seen with obstruction or bleeding.

In patients with locally advanced tumors or in those who are not surgical candidates secondary to comorbidities, combination chemotherapy plus radiation can be definitive. Pathologic complete response can be obtained in up to 30% of patients. Systemic chemotherapy is a preferred method of palliation for metastatic disease. There are many chemotherapy agents available; however, there is not one particular regimen that is standard of care in the first-line setting.

Obstruction and bleeding from large carcinomas of the gastric cardia can be managed by stent therapy, endoscopic laser therapy, or angiographic embolization.⁵