Diagnosis

Clinical evaluation

Although an occlusive tumor may be suspected on a barium swallow or barium meal, the diagnosis is best made with esophagogastroduodenoscopy (EGD, endoscopy); this involves the passing of a flexible tube down the esophagus and visualising the wall. Biopsies taken of suspicious lesions are then examined histologically for signs of malignancy.

Additional testing is usually performed to estimate the tumor stage. Computed tomography (CT) of the chest, abdomen and pelvis, can evaluate whether the cancer has spread to adjacent tissues or distant organs (especially liver and lymph nodes). The sensitivity of CT scan is limited by its ability to detect masses (e.g. enlarged lymph nodes or involved organs) generally larger than 1 cm. FDG-PET (positron emission tomography) scan is also being used to estimate whether enlarged masses are metabolically active, indicating faster-growing cells that might be expected in cancer. Esophageal endoscopic ultrasound (EUS) can provide staging information regarding the level of tumor invasion, and possible spread to regional lymph nodes.

The location of the tumor is generally measured by the distance from the teeth. The esophagus (25 cm or 10 inches long) is commonly divided into three parts for purposes of determining the location. Adenocarcinomas tend to occur distally and squamous cell carcinomas proximally, but the converse may also be the case.

Histopathology

Most tumors of the esophagus are malignant, only about 0.5% are benign. A very small proportion (under 10%) is leiomyoma (smooth muscle tumor) or gastrointestinal stromal tumor (GIST). Malignant tumors are generally adenocarcinomas, squamous cell carcinomas, and occasionally small-cell carcinomas. The latter share many properties with small-cell lung cancer, and are relatively sensitive to chemotherapy compared to the other types.

Signs and symptoms

Dysphagia (difficulty swallowing) is the first symptom in most patients. Odynophagia (painful swallowing) may be present. Fluids and soft foods are usually tolerated, while hard or bulky substances (such as bread or meat) cause much more difficulty. Substantial weight loss is characteristic as a result of poor nutrition and the active cancer. Pain, often of a burning nature, may be severe and worsened by swallowing, and can be spasmodic in character. An early sign may be an unusually husky or raspy voice.

The presence of the tumor may disrupt normal peristalsis (the organised swallowing reflex), leading to nausea and vomiting, regurgitation of food, coughing and an increased risk of aspiration pneumonia. The tumor surface may be fragile and bleed, causing hematemesis (vomiting up blood). Compression of local structures occurs in advanced disease, leading to such problems as upper airway obstruction and superior vena cava syndrome. Fistulas may develop between the esophagus and the trachea, increasing the pneumonia risk; this condition is usually heralded by cough, fever or aspiration.

If the disease has spread elsewhere, this may lead to symptoms related to this: liver metastasis could cause jaundice and ascites, lung metastasis could cause shortness of breath, pleural effusions, etc.

Esophageal Cancer

Esophageal cancer is malignancy of the esophagus. There are various subtypes, primarily squamous cell cancer and adenocarcinoma. Squamous cell cancer arises from the cells that line the upper part of the esophagus. Adenocarcinoma arises from glandular cells that are present at the junction of the esophagus and stomach. Esophageal tumors usually lead to dysphagia (difficulty swallowing), pain and other symptoms, and are diagnosed with biopsy. Small and localized tumors are treated surgically with curative intent. Larger tumors tend not to be operable and hence cannot be cured; their growth can still be delayed with chemotherapy, radiotherapy or a combination of the two. In some cases chemo- and radiotherapy can render these larger tumors operable. Prognosis depends on the extent of the disease and other medical problems, but is fairly poor.