Mark J. Krasna, MDab∗MKrasna@meridianhealth.com,     aMeridian Cancer Care, 1945 Route 33-Ackerman South, Room 553, Neptune, NJ 07753, USA; bRutgers-Robert Wood Johnson Medical School, 125 Paterson Street, New Brunswick, NJ 08903, USA

∗Meridian Cancer Care, 1945 Route 33-Ackerman South, Room 553, Neptune, NJ 07753, USA.

Radiographic imaging using computed tomographic (CT) scan and positron emission tomography/CT are primarily helpful in identifying distant metastases. In general, if patients have evidence of lymph node involvement that is proved pathologically by endoscopic ultrasound/fine needle aspiration, this information is considered definitive, and the patient can be referred for the appropriate stage-specific therapy. Laparoscopy combined with laparoscopic ultrasound and peritoneal lavage has been shown to have sensitivity of 67% and specificity of 92% for lymph node disease. Thoracoscopy may help identify involved lymph node in the mediastinum before resection and help determine the field of radiation.

Keywords

Esophageal cancer • Staging • Imaging • Radiographic staging • Esophageal ultrasound

Key points

Introduction

Staging of esophageal cancer is critical to determining optimal therapy in all patients with this disease. Current use of multimodality therapy in these patients requires a clear understanding of the stage at the time of presentation. This understanding allows us to avoid unnecessary treatment in patients with limited, local disease as well as allows those patients with metastatic disease to receive appropriate treatment and palliation as soon as possible.

Role of staging

Current staging systems depend primarily on the depth of invasion in the wall, the presence of lymph nodes involved with tumor, and the identification of distant metastatic disease.1 The allocation of tumor-node-metastasis (TNM) stage-to-stage groupings is determined by survival; this has been confirmed by the report from the World Esophageal Cancer Consortium, which documented the relationship between staging and survival.2 The order of testing should allow the treating physicians to arrive at the decision regarding whether definitive treatment is feasible as quickly as possible (Box 1).1,3

The most common presenting signs of squamous cell carcinoma or locally advanced adenocarcinoma are dysphagia and odynophagia. For patients with Barrett esophagus and early-stage adenocarcinoma, reflux is the most common presenting sign. Severe weight loss usually occurs after swallowing difficulties begin. Upper esophageal tumors can involve the recurrent laryngeal nerve, causing the patient to have a hoarse voice. Phrenic nerve involvement can trigger hiccups. A postprandial or paroxysmal cough may indicate the presence of an esophagotracheal or esophagobronchial fistula resulting from local invasion by a tumor.4,5

Radiography and upper endoscopy are the most important investigations for evaluating the presence of and extent of esophageal cancer. If esophageal cancer is suspected, the first investigation is usually an upper gastrointestinal endoscopy (esophagogastroduodenoscopy). This endoscopy allows assessment of any obstruction and biopsy to confirm the histology of mucosal lesions.6 Confocal laser endoscopy with targeted biopsy can improve the diagnostic yield for neoplasia and decrease the number of mucosal biopsies in patients in the surveillance group. Endoscopy can identify benign causes of obstructive symptoms as well as allow an opportunity for dilatation and immediate palliation.7

Radiographic diagnosis and staging

A barium swallow is sometimes done before endoscopy to confirm an obstruction, but this is not routinely required. Barium swallow was used in the past as a tool to identify esophageal cancer before endoscopy. Although it can provide information on tumor length, features such as location and size of the tumor are more accurately assessed by endoscopy. Barium studies cannot accurately rule out benign disease or rule in malignancy without a biopsy and are therefore of little value as an initial diagnostic test, unless one is suspicious of a tracheoesophageal fistula. They may provide supportive data in the differentiation of gastroesophageal junction tumors from gastric tumors where large tumors are seen on retroflexion.8

Computed tomography (CT) is still the gold standard for staging patients identified with esophageal cancer. This primarily allows the identification of distant metastatic disease in the lungs, abdominal viscera, and bones. In the absence of metastatic disease, CT can provide some idea of local invasiveness as a guide to determining local resectability. In specific, CT can detect contact with the airway or major blood vessels, which might be an indication of unresectability.9

CT scan of the chest and abdomen is performed if the suspicion of esophageal cancer is high or biopsy confirms the diagnosis. The CT scan assesses tumor bulk and can monitor tumor response to therapy. The CT can define whether the tumor has spread from the esophagus to regional lymph nodes and/or contiguous structures. Oral and intravenous contrast material should be used to ensure optimal pacification of the lumen and visualization of the heart, mediastinal vessels, and liver. An esophageal wall thickness greater than 5 mm is abnormal suggesting a T2 or higher lesion. T1 and T2 lesions generally show an esophageal mass thickness between 5 mm and 15 mm; T3 lesions show a thickness greater than 15 mm. T4 lesions show invasion of contiguous structures on CT and may be suspected by the presence of “contact” between the esophagus and surrounding structures, such as the airway or great vessels. In general, contact with the aorta of more than 90° circumference is considered suspicious for T4 disease.10 In addition, diaphragmatic invasion is suggested by loss of the retrocrural fat planes. Tracheal invasion may be suspected where a midesophageal tumor bulges into the posterior membranous portion of the airway. Suspicious...