Squamous cell esophageal cancer is a type of cancer that begins in the squamous cells lining the esophagus, the muscular tube connecting your throat to your stomach. It is a significant health concern globally.
Understanding Squamous Cell Esophageal Cancer
The esophagus is lined with flat, thin cells known as squamous cells. Squamous cell esophageal cancer, or esophageal squamous cell carcinoma (ESCC), originates when these cells undergo abnormal changes and begin to grow uncontrollably. While ESCC can develop anywhere along the esophagus, it is most frequently found in the upper and middle sections.
ESCC is the most common type of esophageal cancer worldwide, accounting for approximately 90% of all esophageal cancers annually. However, its prevalence varies geographically; it is more common in Eastern Europe and Asia, particularly in regions stretching from Eastern to Central Asia and along the Rift Valley in East Africa. This contrasts with Western countries, where adenocarcinoma is now more prevalent. The uncontrolled growth of these cancerous cells can lead to the narrowing of the esophageal passage, which can impede the normal movement of food.
Risk Factors and Prevention
Several factors increase the likelihood of developing squamous cell esophageal cancer. Chronic heavy alcohol consumption and tobacco use, whether smoking or chewing, are significant contributors. The combination of alcohol and tobacco use presents an even greater risk. Consuming very hot beverages regularly can also irritate the esophageal lining, potentially increasing risk due to thermal damage.
Poor nutrition and diets low in fruits and vegetables are also associated with an increased risk. Specifically, high intake of salted and pickled foods, as well as processed or cured red meats, has been linked to ESCC. Certain medical conditions also predispose individuals to this cancer. Achalasia, a rare disorder where the esophageal muscle does not relax properly, increases the risk of ESCC, with some studies showing a relative risk of 28. Plummer-Vinson syndrome, characterized by difficulty swallowing, esophageal webs, and iron deficiency anemia, also carries a heightened risk, estimated between 4% and 16%. Tylosis, a rare inherited disorder causing thickened skin on the palms and soles, is also recognized as a genetic syndrome linked to ESCC.
Limiting or avoiding chronic alcohol consumption and quitting all forms of tobacco use are primary recommendations. Adopting a balanced diet rich in fruits and vegetables while reducing the intake of excessively hot foods and beverages can also contribute to prevention. Addressing underlying medical conditions like achalasia or Plummer-Vinson syndrome through appropriate medical management may also help reduce the risk of progression to ESCC.
Recognizing Symptoms and Diagnosis
Squamous cell esophageal cancer may not cause noticeable symptoms in its early stages. As the disease progresses, the most common symptom is difficulty swallowing, known as dysphagia, which often feels like food is getting stuck in the chest. This symptom typically appears when the tumor blocks at least half of the esophagus. Unexplained weight loss is another frequent sign, occurring in about 50% of individuals, often due to reduced food intake or changes in metabolism caused by the cancer.
Other symptoms can include chest pain, pressure, or a burning sensation, sometimes occurring a few seconds after swallowing. A persistent cough, hoarseness that does not resolve, and worsening indigestion or heartburn unresponsive to typical treatments are also potential indicators.
Diagnosis typically begins with a physical examination and a review of symptoms and medical history. A barium swallow, or esophagram, is often performed, where the patient drinks a barium-based solution that coats the esophagus, allowing abnormalities to be seen on X-rays. Endoscopy, specifically an esophagogastroduodenoscopy (EGD), is a common diagnostic test. During this procedure, a thin, flexible tube with a camera is passed down the throat to visualize the esophagus, and tissue samples (biopsies) from abnormal areas can be collected for microscopic examination to confirm cancer. If cancer is confirmed, imaging tests like a CT scan (computed tomography) and PET scan (positron emission tomography) are often used to determine the extent (stage) of the cancer and check for spread to other parts of the body.
Treatment Options
Treatment for squamous cell esophageal cancer is typically individualized, taking into account the cancer stage, the patient’s overall health, and personal preferences. The main treatment modalities include surgery, chemotherapy, and radiation therapy, often used in combination.
Surgery, often an esophagectomy, involves removing part or all of the esophagus and sometimes nearby lymph nodes, then reconstructing the digestive tract. This is a complex procedure typically considered for early-stage or resectable tumors. Chemotherapy uses anti-cancer drugs, administered intravenously or orally, to kill cancer cells throughout the body or to shrink tumors before surgery. Radiation therapy uses high-energy X-rays or other forms of radiation to destroy cancer cells or inhibit their growth, often delivered externally by a machine.
Combined approaches, such as chemoradiation, are frequently used. This involves administering chemotherapy and radiation therapy concurrently, which has been shown to be superior to radiation alone for certain stages of ESCC. Preoperative chemoradiation, also known as neoadjuvant chemoradiation, followed by surgery, is a standard strategy for locally advanced resectable esophageal cancer. For patients who cannot undergo surgery, definitive chemoradiation is a viable option. Recent research also explores the addition of immunotherapy to chemoradiation, showing potential for improved outcomes.