Esophageal Adenocarcinoma

Esophageal adenocarcinoma is a malignant tumour arising from the glandular cells of the lower esophagus.

With a survival rate of 20%, early detection is key in improving prognosis.

Epidemiology

Esophageal adenocarcinoma (EAC) is more common in men than women, typically affecting individuals over 50 years old. The most recent statistics show a 5-year survival rate of 20% largely due to the late detection of the cancer. [2]

Symptoms & Signs

Symptoms/signs of esophageal adenocarcinoma:

Dysphagia (difficulty swallowing) for solid foods and eventually liquids
Long-term gastroesophageal reflux diseases (GERD) associated with chronic chest pain
Unintentional weight loss is a sign that indicates advanced disease
Other symptoms include hoarseness, chronic cough, or gastrointestinal bleeding [2]

Etiology

Most commonly associated risk factors among many others that contribute to the development of esophageal adenocarcinoma:

History of tobacco smoking

Symptoms of long term gastroesophageal reflux (GERD)

Obesity

Additionally, a lack of protective antioxidants and fibers such as a lower consumption of fruits and vegetables further increases the risk of developing EAC. Another protective mechanism is the presence of H. pylori as it reduces the symptoms of GERD. [1]

Affected Anatomy

Esophageal adenocarcinoma affects the lower esophagus near the gastroesophageal junction, where the esophagus meets the stomach. In the case of EAC, the tumour initially appears as an irregular mass causing the lumen of the esophagus to narrow.

As the cancer progresses, the cancerous cells invade the layers of the esophageal wall which can lead to other complications such as obstruction of the esophagus.

Histology: Key Features of EAC

One of the key features of esophageal adenocarcinoma is the histological appearance of Barrett’s esophagus. Due to the acid reflux, the esophageal epithelium undergoes metaplasia, which refers to the change in the shape of the epithelial cells of the tissue. In Barrett’s esophagus, we see the change of a normal squamous (flat-shaped) epithelium into a columnar (column-shaped) epithelium. [1,2]

BARRETT'S ESOPHAGUS

Diagnosis

A number of different diagnostic tests and tools can be used to ascertain features of esophageal cancer and confirm the diagnosis.

Barium swallow studies

Patient swallows barium to help visualize structural abnormalities such as a narrowed esophagus as well as the presence of irregular masses.

Biopsy

A biopsy can be taken to confirm the presence of cancerous cells and determine any histological features such as Barrett's esophagus, that indicate esophageal adenocarcinoma

Upper Endoscopy

Inserting a long, flexible tube with a camera down the esophagus to directly visualize the esophageal lining. It also allows for the collection of a biopsy for further tests

Other Tests: CT scans, PET scans, etc.

These tests are used to determine the extent of tumour spread.

Treatment

Treatment for esophageal adenocarcinoma depends on the stage of the disease:

Early Stage Tumours

Treatment begins with removal of the tumour which may require partial or complete removal of the esophagus also known as an esophagectomy.

Metastatic Tumours

Metastatic tumours have spread to regional lymph nodes or distant organs.
Treatment begins with chemotherapy and radiation therapy to shrink the tumour before surgical removal.
In the some cases, ablation therapy via electromagnetic radiation can be used to destroy cancerous tissue

Prognosis

Prognosis for esophageal adenocarcinoma also depends on the stage of the tumour at the time of diagnosis.

Early Stage Tumours

Tumour is constrained to the first two layers of the esophageal wall
- mucosa and submucosa
These tumours have a better prognosis with higher survival rates; a good prognosis is also associated with early diagnosis usually at the stage of heartburn symptoms.

Metastatic Tumours

Tumour invades the deeper layers of the esophageal wall and beyond
- muscularis propria and adventitia
- to distant organs
Prognosis worsens and survival rates decline significantly.