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Dr QM Leong
Dr QM Leong

Can A Colonoscopy Detect Stomach Cancer? 4 Critical Facts 

Stomach cancer, also known as gastric cancer, is a significant health challenge globally. This disease can be deadly if not detected and treated early, and it primarily targets the stomach’s inner lining. According to the NIH, stomach cancer is the fifth most common cancer in the world, and the fourth leading cause of death.

On the other hand, a colonoscopy is a diagnostic procedure primarily used to inspect the inner lining of the colon and rectum. Its primary purpose is to identify and sometimes treat issues within the colon and rectum.

So, the question becomes, can a colonoscopy detect stomach cancer? This article clarifies whether a colonoscopy can detect stomach cancer and suggests why your doctor might recommend this procedure.

1. Can A Colonoscopy Detect Stomach Cancer?

To put it simply, a colonoscopy is designed to detect diseases of the colon and rectum, primarily colorectal cancer or colon cancer, and not specifically stomach or gastric cancer. While the scope might visualise the very end of the stomach, it is not the recommended tool for stomach cancer screening.

2. Why Would Your Doctor Recommend A Colonoscopy?

There are various reasons why a doctor might suggest undergoing a colonoscopy. These include:

Detecting Colorectal Cancer

A colonoscopy is primarily recommended for screening colorectal cancer in individuals over 50 or earlier if risk factors present. Since the colonoscopy procedure will examine the entire colon, your doctor will be able to make a sound diagnosis.

Investigating Digestive Symptoms

If a patient experiences unexplained abdominal pain, rectal bleeding, or persistent changes in bowel habits, a colonoscopy might be advised to diagnose the cause.

Monitoring Conditions

For individuals with diagnosed gastrointestinal diseases, such as ulcerative colitis or Crohn’s disease, regular colonoscopies might be advised to monitor the condition and check for any changes or complications.

Evaluation Of Polyps

If polyps (small growths) are identified during other imaging studies, a colonoscopy can be used to closely inspect and often remove them before they can develop into cancer cells.

Symptoms Mimicking Other Diseases

Sometimes, symptoms like abdominal pain or changes in bowel habits might be mistaken for irritable bowel syndrome (IBS) or other similar cases. A colonoscopy can help rule out more serious diseases and pinpoint the actual cause of the symptoms.

3. The Right Test For Stomach Cancer: Endoscopy

While a colonoscopy primarily examines the colon and rectum, if a doctor suspects a patient may have stomach or gastric cancer, they would most likely recommend an endoscopy.

What Is An Endoscopy? 

An endoscopy is a procedure where the doctor uses a flexible tube with a light and camera attached to it, called an endoscope, to visualise the digestive tract. An endoscopic procedure is a non-surgical way to examine different parts of the digestive system, including the oesophagus, stomach, and the beginning of the small intestine.

Detecting Gastric Cancer And Other Ailments With Endoscopy

Much like a colonoscopy ruling out other symptoms and conditions, an endoscopy will give a clearer view of your stomach and give the doctor the right details to make a proper diagnosis. Sometimes, the symptoms might be similar but will lead to the discovery of other ailments.

Stomach Cancer (Gastric Cancer)

An endoscopy is the primary diagnostic test for stomach cancer. The doctor can see any unusual areas in the stomach lining and use the endoscope to take a small tissue sample (biopsy) to test cancer cells.

4. Early Detection And Preventive Care

Early detection is paramount when dealing with any form of cancer, including stomach and colorectal cancer. Detecting cancer in its initial stages can significantly affect prognosis and treatment options.

When it comes to gastrointestinal cancers, especially colorectal and stomach cancer, early detection can drastically reduce the severity and progression of the disease.

Tips For Preventive Care

  1. Regular Screenings: Schedule regular screenings, particularly if you have risk factors associated with colorectal or stomach cancer. This may include a colonoscopy or endoscopy, depending on your history and needs.
  2. Be Aware of Symptoms: Be vigilant about symptoms like persistent abdominal pain, changes in bowel habits, or any other unusual gastrointestinal symptoms. While symptoms could indicate conditions like irritable bowel syndrome, they could also point towards more severe diseases.
  3. Know Your Family History: If you have a family history of stomach cancer, colorectal cancer, or other gastrointestinal diseases, it’s crucial to communicate this to your doctor. This might necessitate more frequent screenings.
  4. Healthy Lifestyle Choices: To improve overall health, one can maintain a balanced diet, exercise regularly, and avoid excessive alcohol and tobacco consumption. This can reduce your risk for several cancers, including gastric and colorectal cancer, and also help to relieve symptoms.
  5. Be Informed About Diseases and Conditions: Understanding conditions like ulcerative colitis can be essential, as they might increase your risk for certain cancers.
  6. Seek Medical Advice: Consult with a doctor at any sign of persistent symptoms or discomfort. Regular check-ups and discussions about potential risk factors or concerns can help early detection and preventive care.

Conclusion On Whether A Colonoscopy Can Detect Stomach Cancer

In summary, a colonoscopy is a valuable tool primarily designed to detect colon cancer by examining the colon and rectum for polyps or cancer cells. While it is instrumental for colorectal cancer screening, it does not directly examine the stomach and, therefore, cannot reliably detect stomach or gastric cancer.

However, recognising the importance of early detection, maintaining open communication with your doctor, and undergoing appropriate screenings based on your risk factors is vital for overall gastrointestinal health.

If you’re concerned about any gastrointestinal symptoms or need expert consultation, consider engaging with a colorectal surgeon in Singapore with over 2 decades of experience like Dr QM Leong for early detection and general surgery services. Schedule a consultation today

Frequently Asked Questions About Colonoscopies Detecting Stomach Cancer

What Are The Primary Symptoms Of Stomach Cancer?

Symptoms can include persistent abdominal pain, unexplained weight loss, difficulty swallowing, indigestion, and a feeling of fullness after eating small amounts.

Can I Get Stomach Cancer If I Have Irritable Bowel Syndrome?

IBS doesn’t directly increase the risk of stomach cancer. However, any persistent symptoms should be discussed with a doctor to rule out other conditions.

What Is The Primary Difference Between Stomach Cancer And Colorectal Cancer?

Stomach (or gastric) cancer begins in the stomach. In contrast, colorectal cancer starts in the colon or rectum, parts of the large intestine. Although they belong to the digestive system, they occur at very different areas.

What Is The Survival Rate For Stomach Cancer?

The survival rate for stomach cancer depends on factors like the stage at diagnosis and the individual’s overall health, but on average, the 5-year survival rate is around 36%.

How Does Stomach Cancer Usually Start?

Stomach cancer typically begins when the cells in the inner lining of the stomach undergo genetic changes and transform into cancerous cells. This process often starts with the formation of precancerous lesions like stomach ulcers or chronic inflammation.