Squamous Cell Carcinoma Of The Esophagus
Esophageal squamous cell carcinoma (ESCC) is a type of esophageal carcinoma (EC; see this term) that can affect any part of the esophagus, but is usually located in the upper or middle third.
Epidemiology
ESCC has an estimated annual incidence of 1/29,400.
Clinical description
The average age of onset of ESCC is between the ages of 60 to 70 years and it is more frequently seen in males. It is usually asymptomatic until an advanced disease stage with common presenting symptoms being dysphagia (at first with solids then progressing to fluids) and weight loss. Less commonly odynophagia, hoarseness of voice, coughing, or chest pain can be presenting features. Tumors are typically found in the middle and the upper third of the esophagus.
Etiology
The exact etiology is unknown. Cigarette smoking and alcohol abuse are the principal risk factors. There is also an association with idiopathic achalasia (see this term), a motility disorder of the esophagus.
Diagnostic methods
Endoscopy and a biopsy will establish the diagnosis. For staging, a computed tomography (CT) scan of the neck, chest and abdomen, or CT combined with a positron emission tomography (CT-PET) scan will identify the primary tumor in most cases as well as any spread to the lymph nodes and organs such as the liver, lungs and bone. Endoscopic ultrasound (EUS), the combination of an ultrasound probe on an endoscope, is also increasingly used for staging, and is of particular value for early cancers. In upper or mid-esophageal tumors where there is a possibility of invasion of the airway (trachea or bronchi) a bronchoscopy may also be required.
Differential diagnosis
Differential diagnoses include idiopathic achalasia (see this term), benign esophageal stricture, an esophageal web, and occasionally lung cancer.
Management and treatment
Treatment may be with curative intent when the disease is confined to the esophagus and even when local nodes of the primary tumor are involved, and when the patient is fit enough for treatment. Treatment with palliative intent, targeted on symptom control and quality of life, but not cure, is the mainstay of treatment when the disease is advanced or incurable, or the patient is unfit for therapy due to significant co-morbidities. The traditional treatment of ESCC is surgical resection; this is usually via a transthoracic resection, and occasionally by a neck incision. In some cases a transhiatal esophagectomy is performed. The use of minimally invasive approaches to perform these operations is increasing in use. There is also an increasing use of chemotherapy or of the combination of chemotherapy and radiotherapy before and after surgery. A number of clinical trials support this practice, particularly where the tumor is locally advanced, and this is increasingly the standard of care in Europe and North America. The chemotherapeutic drugs most often used in combination are epirubicin, cisplatin and 5-fluorouracil (known as ECF). Capecitabine and oxaliplatin are less toxic agents that can be used in those with cardiac and renal problems. There is also an increasing use of radical, high-dose radiotherapy and chemotherapy for ESCC which avoids a surgery, and the outcomes are equivalent to surgical or multimodality approaches. For palliative approaches, self-expanding metal stents (SEMS) can relieve dysphagia, and chemotherapy, radiation therapy and laser-based approaches are also considered. Palliation may also involve nutritional support via feeding devices such as percutaneous endoscopic gastrostomy (PEG) tubes.
Prognosis
As ESCC is usually diagnosed at an advanced disease stage, the overall prognosis is poor, with an overall 5-year survival of between 10-20%. In patients treated with curative intent the cure rate currently approaches 40%.