Stomach cancers tend to develop slowly over many years. Before a true cancer develops, pre-cancerous changes often occur in the stomach’s inner lining (mucosa). These early changes rarely cause symptoms, so they often go undetected.
A thorough and accurate stomach cancer diagnosis is the first step in developing a treatment plan. Various tools and tests are designed for stomach cancer diagnosis, evaluating the disease, and creating an individualized treatment plan.

Tests for stomach cancer diagnosis

Some tests and exams may help detect, diagnose and stage stomach cancer. First, your doctor may gather your personal and family medical history and ask about any symptoms you’re experiencing, including.


  • Bloating
  • Pain
  • Issues with eating

Your doctor will also consider any risk factors that may help stomach cancer diagnosis more likely.
Next, a physical exam may be conducted. Your doctor may feel your abdomen to detect any abnormalities.
Blood tests to measure your red blood cell count and faecal tests to check for blood in your stool may be ordered. Both of these factors may be affected by bleeding from stomach cancer.
If stomach cancer is suspected, your primary doctor will refer you to a gastroenterologist, a doctor with expertise in the digestive tract organs who may order additional testing.
Lab tests may be used to help stomach cancer diagnosis. They include

  • Advanced genomic testing examines a tumour’s DNA for mutations or alterations that may drive cancer growth. By identifying the transformations in a cancer cell’s genome, doctors may better understand what caused the tumour and tailor treatment based on these findings.
  • Complete blood count (CBC) tests determine the numbers of the different types of cells in the blood. A CBC blood test may help determine whether a patient has too few red blood cells, which causes anaemia.
  • Liver function tests may be performed to assess the function of your liver, to which stomach cancer can spread.
    Nutrition panel helps evaluate patients for deficiency of nutrients, such as vitamin D and iron. The test helps us identify the nutrients patients need to be replaced or boosted to support their quality of life.

Imaging tests for stomach cancer diagnosis

Imaging tests may be used to help diagnose and stage stomach cancer. They include:

  • Computed tomography (CT) scans are taken to reveal detailed images of your abdomen. The information obtained from CT scan images helps doctors detect cancer, determine its location in the stomach, and see whether it has spread to other abdominal organs.
  • Magnetic resonance imaging (MRI) uses strong magnetic fields and radio waves to produce detailed images. These tests also allow for more excellent soft tissue contrast than a CT scan. This test isn’t used as often as a CT scan to detect stomach cancer. Still, it helps to determine whether cancer has spread to other organs, such as the liver.
  • Positron emission tomography/computed tomography (PET/CT) scans help doctors detect stomach cancer and determine the stage of the disease and whether it’s spread.
  • Ultrasound may be used if fluid is found in your abdomen. Ultrasound produces images of organs from high-energy sound waves. It echoes to help your care team detect and stage stomach cancer. It may also be used to check for tumours that have spread to other organs for stomach cancer diagnosis.

Suppose your doctor finds abnormalities during this procedure. In that case, the next step may be an endoscopic procedure or another diagnostic imaging test. These tests help in both detecting and staging stomach cancer.

stomach cancer diagnosis
Procedures for stomach cancer diagnosis

Endoscopic procedures

  • These minimally invasive, outpatient endoscopic procedures allow a doctor to see inside the stomach. They include:
    Esophagogastroduodenoscopy (EGD), an upper endoscopy, is the primary test for stomach cancer diagnosis. To undergo an EGD procedure, you first receive a sedative. A gastroenterologist inserts an endoscope (a thin, lighted tube) into your mouth. They pass the endoscope through your throat, oesophagus, stomach, and the first part of your small intestine. The endoscope lets your gastroenterologist see inside these organs to check for abnormalities, such as tumours, ulcers, obstructions and inflammation. They obtain biopsies of abnormal tissue through the endoscope. The tissue is then analyzed in the laboratory to look for signs of cancer. Although an endoscopy may help detect some types of stomach cancer, other types are more complex and require additional diagnostic testing.
  • Endoscopic ultrasound (EUS) helps your gastroenterologist examine your stomach and organs, such as your pancreas, liver, gallbladder and bile duct. This test for stomach cancer uses sound waves to identify tumours and nearby lymph nodes to which the cancer may have spread. EUS allows your gastroenterologist to determine whether cancer has spread through multiple layers of your stomach, helping your doctors stage the disease and tailor your treatment plan.


If your doctor finds any unusual or suspicious areas during your upper endoscopy, an essential stomach cancer diagnosis procedure called a biopsy is required to determine whether cancer cells are in the stomach. This procedure is the only way to know whether cancer is present. In a biopsy, a small sample of cells is taken from a tumour and analyzed by a pathologist to determine if the cells are cancerous.
The samples are checked to see if they contain cancer, and if they do, what kind it is (for example, intestinal or diffuse adenocarcinoma, carcinoid tumour, gastrointestinal stromal tumour [GIST], or lymphoma).
If stomach cancer is found, more lab tests may be done on the biopsy samples to learn more about the cancer cells. This might affect how the cancer is treated.