Recent research suggests that blood tests may show markers of oral cancer. But a blood test isn’t enough to confirm an oral cancer diagnosis. A biopsy is the only way to confirm it.

Blood tests for oral cancer may help detect certain blood markers associated with cancer cells or the body’s response to cancer.

However, doctors don’t typically use them as the primary method to diagnose oral cancer, as these markers may also be present in other conditions. Therefore, no blood test can diagnose oral cancer.

Still, a doctor may recommend blood tests for people who already have an oral cancer diagnosis. In these cases, a blood test can:

  • assess overall health
  • determine the cancer stage
  • monitor treatment effectiveness
  • identify specific cancer-associated markers, such as tumor markers

This article explores the possibility of using blood tests to help detect oral cancer and discusses their potential benefits.

Early symptoms of oral cancer

Some early symptoms of oral cancer include:

  • Mouth sores or ulcers: Mouth sores or ulcers that do not heal within 3 weeks can indicate oral cancer. These can develop anywhere in the mouth, including the lips, tongue, cheeks, and the roof or floor of your mouth.
  • Red, white, or discolored patches: These patches may develop suddenly. They may be painful or tender.
  • Difficulty swallowing or chewing: These symptoms might be accompanied by a feeling of something stuck in your throat.
  • Changes in speech: Oral cancer may cause a change in speech or voice, such as a hoarse or raspy tone.

A blood test can help diagnose oral cancer by detecting specific markers associated with cancer cells or your body’s response to cancer. Doctors may detect certain cancers, like oral cancer, through irregularities in the blood cell count.

A 2021 study found that blood testing combined with machine learning could accurately detect oral cancer about 9 out of 10 times. However, more research is needed.

Blood tests, such as a complete blood count (CBC), can help a doctor identify the levels of different types of blood cells.

A doctor may also perform a serum protein electrophoresis test to analyze the various proteins in the blood, which can help detect cancerous conditions, including oral cancer.

However, blood tests alone cannot definitively diagnose oral cancer. Doctors typically use them with other diagnostic methods to confirm the diagnosis.

The procedure for a blood test is straightforward. It aims to collect your blood sample for laboratory analysis.

The steps involved in the procedure include:

  1. Preparation: Before the blood test, consider informing the healthcare professional about any medications you take. Certain drugs may affect the test results. You may also be required to fast for a specific period, typically around 8–12 hours, especially if other tests like blood sugar levels are getting evaluated.
  2. Identification: When you arrive at the clinic, a healthcare professional will verify your identity by asking for your name and other personal details. This identification process ensures that the blood sample is correctly labeled and matched to you.
  3. Needle insertion: While you’re seated comfortably, a healthcare professional uses an antiseptic to clean the skin over a vein, usually in your arm. They then insert a thin needle into the vein to draw blood. The needle insertion may cause a brief sensation of discomfort.
  4. Blood collection: Once the needle is in place, blood flows into a collection tube from your arm. The amount of blood collected is usually small, often a few milliliters. The technician may collect multiple tubes for different tests, depending on what your doctor ordered.
  5. Pressure and bandage: After they draw your blood, the healthcare professional removes the needle and applies pressure over the puncture site with a cotton ball or gauze. This helps stop any bleeding. They may then place a small adhesive bandage or a piece of tape over the puncture site to protect it.

Doctors use various methods to test for oral cancer, including:

  • Physical examination: A doctor visually inspects your mouth, throat, tongue, and other oral tissues for abnormal growths, sores, or changes in color or texture.
  • Biopsy: A doctor may perform a biopsy if suspicious areas are identified during the physical exam. This involves taking a small tissue sample from the affected area for lab analysis.
  • Imaging tests: Doctors may use imaging techniques, such as CT, MRI, or PET scans, to assess the extent of the cancer and determine whether it has spread to nearby structures or other body parts.
  • Endoscopy: Sometimes, a doctor may use an endoscope, a thin, flexible tube with a light and camera on the end, to examine your throat and voice box. This provides a detailed view of the upper digestive tract.

Can a home test kit detect oral cancer?

Currently, no widely available home test kits can reliably detect oral cancer.

Diagnosing oral cancer typically requires a clinical exam by a healthcare professional, imaging tests, and a tissue biopsy for a definitive diagnosis.

These methods require specialized equipment and expertise that a home test kit cannot replicate. Home test kits may have limitations because they may not have the accuracy and sensitivity needed to detect oral cancer reliably.

Blood tests alone cannot provide a definitive diagnosis of oral cancer.

However, a complete blood count and electrophoresis can help provide information on blood cells and protein patterns that can indicate the presence of cancerous conditions.