Galleri: New Blood Test for Cancer

How would you beat cancer without knowing you have it?

Galleri is a new multi-cancer blood test. It is a promising diagnostic solution to detect cancers. A biotech company, GRAIL manufactured it. However, the test is not exactly new. Back in 2016, Illumina Inc. (another biotech company) announced the formation of this blood test. In fact, the company expressed that it may “decrease cancer mortality” in the future.


You might think how can a cancer blood test decrease the number of patients dying from the disease? As cancer progresses from stage 1 to the next, it barely shows any symptoms. This is why most people don’t go for cancer screenings. Such a condition allows cancer cells to grow and divide. Delayed detection also leads to the spread of tumors to nearby tissues, lymph nodes, and organs. And most importantly, it becomes tough to treat cancer at later stages. For example, a blood cancer medicine for the early stage is expected to clear tumors. Whereas, a later-stage drug manages the symptoms and extends survival.


Most patients presume that blood tests are only essential for blood cancer treatment. It’s not true. A multi-cancer early detection test like Galleri utilizes a blood sample. It looks for DNA fragments and their cancer-specific signals in samples to diagnose cancer. It also specifies the location of the occurrence of cancer signals in the body.


The Circulating Cell-Free Atlas Study was intended to validate multi-cancer early detection blood tests in 15,000 subjects. These were people either with or without a known cancer diagnosis. The tests provided negative results to 99.5% of participants.

An earlier version of Galleri identified 13 cancer types in 29 subjects. A PATHFINDER study that examined 6,629 subjects aged above 50 years showed this. An estimated 40% of cancer diagnoses resulting from positive test results were stage 1 or stage 2 tumors.

Which cancers can Galleri diagnose?

The Galleri blood test is expected to detect more than 50 kinds of cancers (malignant tumors). Doctors recommend this test to diagnose cancer in those suspected of the symptoms. Some common types of tumors it detects include cancer of the:

  • Stomach
  • Kidney
  • Uterus
  • Anus
  • Lung
  • Liver
  • Breast
  • Cervix
  • Esophagus
  • Pancreas
  • Mouth
  • Bone marrow and blood


Galleri blood test is not yet approved by the US Food and Drug Administration. Thus getting the test done outside the clinical trial is not a case until it gets approved.

Who should go for the Galleri Blood Test?

Galleri tests for multiple cancers make the way for early diagnosis. Experts believe that it can help manage the increasing cancer threat globally. To know who should go for the test, it is necessary to understand who all are prone to the disease. Mainly, adults aged above 50 years are at a greater risk of developing cancer. People with a family history of cancer are also considered vulnerable. Other risk factors may include:

  • Drinking alcohol
  • Smoking or using smokeless tobacco
  • Having a BMI (body mass index) exceeding 30
  • Being diabetic or having any other chronic disease
  • Being exposed to chemicals or radiation


Since certain types of cancers are prevalent in children, doctors may prescribe regular screening from the age of 10 years. However, this is limited to those who have a medical history of cysts or a parent having cancer.

Who should not go for the Galleri Blood test?

Currently, there is a group of ineligible people who can’t go for the Galleri blood test. This includes:

  • Pregnant women
  • People aged below 39 years
  • People residing outside the US
  • Certain cancer patients


Though this is not the final group of ineligible people. As GRAIL takes this test to the US FDA approval, there shall be changes.