Esophageal cancer can be diagnosed with the help of certain imaging studies and other tests.
If a patient presents with the symptoms of esophageal cancer the tests are prescribed.
Diagnosis begins with detailed history of symptoms and inquiry into the known risk factors and exposures (e.g. smoking, alcohol consumption etc.) This is followed by a thorough physical examination.
Investigations to diagnose esophageal cancer
There are several investigations used for diagnosis, these include barium swallow, endoscopy, biopsy and so forth. (1-5)
The patient is made to drink a barium solution. This is followed by x-rays of the esophagus and stomach.
Due to the Barium the esophagus and the stomach shows up as white structures in the X ray plates.
This helps diagnosis of abnormalities and the tumor location at times. This test is also called Upper GI series.
A thin tube with a camera on its tip is inserted through the mouth or nose into the esophagus.
The images of within the esophagus are visible via the camera.
The pathway of the entry of the tube is anesthetized using a local anesthetic spray before insertion.
This is also called upper GI endoscopy or esophagoscopy.
Sometimes esophagus, stomach as well as the initial part of the intestine called duodenum may be examined at the same sitting. This is called Esophaghogastroduodenoscopy.
This is the surest test for esophageal cancer. In endoscopy, tissue samples may be gathered from the tumor after it is visualized.
A pathologist then checks the tissue under a microscope.
Other tests for esophageal cancer
Other tests for esophageal cancer include:-
- Stool examination – Stool examination may show blood.
- Routine blood tests – Complete blood tests for general health, evidence of malnutrition etc. may be needed. Liver function tests are prescribed in cases of advanced cancer where the liver may be affected.
Staging of esophageal cancer
Once the cancer is diagnosed it needs to be staged.
Staging helps in determining and planning therapy and also helps predict outcome of therapy.
It assesses how deeply the cancer has invaded the esophagus, whether the cancer has affected nearby tissues and whether the cancer has spread.
Spread to the nearest lymph nodes, bones, or other organs like liver and lungs are assessed. (1-5)
Tests for staging esophageal cancer
Recommended staging tests for esophageal cancer include endoscopic ultrasound, chest or thoracic CT scan, Positron Emission Tomography scan and so forth. (1-5)
An endoscope is passed within the esophagus which has been numbed with anesthetic.
The tip has a probe that sends in ultrasound waves. These bounce off the tissues nearby.
The computer assesses the picture with the help of this. The picture can show how deeply the cancer has invaded the wall of the esophagus.
Chest or thoracic CT scan and Chest MRI
These are sophisticated imaging studies that give detailed picture of the chest and abdomen and show the estent of spread of the cancer.
Positron Emission Tomography (PET) scan
A PET (Positron Emission Tomography) scan is also an imaging study.
A small amount of radioactive sugar is injected. The scanner picks up the movement of the sugar within the body.
Cancer cells show up brighter in the picture because of higher and more rapid uptake of the sugar.
This scan shows the extent of spread of the cancer.
A bone scan helps detect extent of spread of the cancer to the bones.
A bronchoscopy is similar to an upper endoscopy. The doctor passes a thin, flexible tube with a light on the end into the mouth or nose, down through the windpipe, and into the lungs.
A bronchoscopy may be performed if a patient’s tumor is located in the upper two-thirds of the esophagus to see if the tumor is growing into the person’s airway or trachea or bronchi.
During a laparoscopy small incisions are made over the abdomen under general anesthesia in the surgical set up.
The surgeon inserts a thin, lighted tube called the laparoscope into the abdomen. This is used for taking tissue samples and biopsies to look for cancer spread.
Stages of esophageal cancer
The stages of esophageal cancer are:
- Stage 0: It is also called carcinoma in situ. Here the cancer has not spread beyond the esophagus.
- Stage I: The cancer has grown through the inner layer or mucosa to the next layer the submucosa.
- Stage II is characterized by either spread to submucosa and lymph nodes or to the muscle layer and lymphnodes or through the outer layer of the esophagus.
- Stage III is characterized by growth through the outer layer of the esophagus and lymph nodes or invaded nearby structures, such as the airways and lymph nodes.
- Stage IV indicates cancer cells have spread to distant organs, such as the liver.