Is There a Cancer Test?

So, you want to know if there is a cancer test. And if so, is there a rapid test for cancer like there is for COVID? 
The answer is yes, no, sort of.
While there is no one rapid cancer test like there is a rapid COVID test, there are multiple ways to assess for cancer.
Not all of the cancer tests I will discuss here are strictly for diagnosing cancer though.
While some of these lab tests help diagnose cancer; they are also used to monitor the progress of cancer treatments as well. 

Diagnostic testing is common.

(Read: What is a Cancer Journey? and The Day I Met Cancer in the Mirror)

Sometimes a routine lab test finds an indicator of cancer, though that was not the intention of the test. And sometimes, your health practitioner orders diagnostic tests to specifically look for cancer.

In this article, we will look at twelve common lab cancer tests.

Take Note: The tests mentioned here are useful tools in detecting cancer, but these tests are used for many reasons other than just cancer detection. Even though this article mentions cancers that may be indicated by abnormal blood values, abnormal blood values DO NOT ALWAYS INDICATE CANCER. Finally, this is an educational tool, not a diagnostic tool.

Please keep in mind as you learn about common tests used in cancer detection, that cancer detection is not the only reason these tests may be performed. Lab tests are used in conjunction with other diagnostic tests to confirm a cancer diagnosis.

Health care professionals often order a CBC lab test.

Here is more information on a CBC.

CBC stands for Complete Blood Count

To obtain a CBC, a phlebotomist inserts a needle into a vein and draws out a blood sample.

What This Test is Looking For:

Three types of blood cells:

·         Firstly,  are the “Fatigue Fighters” = RBC = red blood cells. These cells carry oxygen to all the cells in the body. One cause of fatigue is a low number of RBCs.

·         Secondly are the “Infection Fighters” = WBC = white blood cells. These cells go throughout the body looking for infections to attack.

·         And thirdly are the “Bleeder Fighters” = Platelets = thrombocytes. These cells travel through the blood looking for cuts. When they find bleeding, they stick together to make a clot to stop the bleeding.

Note: These are the three main cells in a CBC. The rest of the components in a CBC give more information about the three types of cells.

Potential Cancer Source:

·         Too many RBCs may be due to polycythemia vera.

·         Not enough RBCs may be due to bone or kidney cancer.

·         High WBCs may indicate leukemia or lymphoma.

·         Low WBCs may be due to bone marrow cancer.

·         High Platelets may be indicative of myeloproliferative neoplasms.

·         Low Platelets may indicate leukemia or lymphoma.

Why a CBC is not just a cancer test.

As we have just discussed, an excess of RBCs may indicate polycythemia vera. But excess RBCs may also be caused by heart disease, heart failure, smoking, lung disease, or hypoxia.

Low RBCs might be caused by sickle cell disease, kidney disease especially chronic kidney disease, or even malnutrition.

An elevated WBC level may be due to several different reasons which are why this is not a good cancer test by itself. Some causes of elevated WBCs include infection, stress, chronic lung disease, inflammation, and allergic reaction.

On the other hand, low WBCs may be due to some autoimmune disorders including lupus and rheumatoid arthritis, bone marrow damage, infection like hepatitis, or even some medications.

Infection, hemolytic anemia, or a reaction to steroids are some of the reasons you may have a high platelet count.

Or a low platelet count may be due to substantial alcohol consumption, some viral infections, and anemia.

CMP stands for Comprehensive Metabolic Panel.

This is another common diagnostic blood test which again is not strictly a cancer test.

To obtain a CMP, the phlebotomist inserts a needle into a vein to draw out a blood sample

What This Test is Looking For:

While a CBC measures the number of cells in the blood, this test measures fourteen substances in your blood. These include:

·         Glucose = blood sugar. Glucose gives your brain and body energy

·         Calcium = is a mineral found in bones and blood

·         Total protein = measures the proteins albumin and globulins

·        Bilirubin = waste product from RBCs breaking down

·         BUN = blood urea nitrogen which is a waste product in the blood that the kidneys get rid of

·         Creatinine = waste product from muscle breakdown that the kidneys get rid of

·         Albumin = is a protein in the blood. This protein keeps the blood vessels from leaking. It also transports many substances throughout the body

Electrolytes:

·         Sodium = helps maintain the proper fluid level in the body, as well as supports proper blood pressure, muscle, and nerve function

·         Potassium = helps nerves and muscles function properly

·         Bicarbonate = this shows how much carbon dioxide is in the blood

·         Chloride = this electrolyte helps balance the blood acid and base levels

Liver enzymes:

·         ALP = alkaline phosphatase

·         ALT = alanine transaminase

·         AST = Aspartate aminotransferase

These chemical substances each have their own purpose, but together they help support chemical reactions in the liver.

Some cancers that may cause abnormal CMP values to include:

·         Lung cancer

·         Breast cancer

·         Kidney cancer

·         Liver cancer  

·         Pancreatic cancer

And more.

As a cancer test, elevated liver enzymes may indicate cancer of the pancreas, liver, or bile duct.

But liver transplant rejection, hepatitis, and malnutrition will also alter liver enzyme values.

If there is a suspicion of cancer, your doctor will order more bloodwork and other tests.

Other blood tests also aid your physician in determining if you have cancer. Let’s look at some now.

Tumor markers that may be a cancer test:

Tumor markers look for chemicals made by cancer cells. Cells other than cancer cells can also make these chemicals, so tumor markers are not used to diagnose cancer but are used to monitor the effectiveness of cancer treatments.

A tumor marker is another lab blood test. Once again, the phlebotomist inserts a needle into a vein and draws out a blood sample.

·         PSA = prostate-specific antigen

            - Potential cancer: Prostate cancer

            Though a PSA is used for prostate cancer detection,  an enlarged prostate can also cause an elevated PSA which is why this test is not just a cancer test.    

·         CA 125 = cancer antigen 125

·         Potential cancer source:

-Ovarian cancer

 -Pancreatic cancer

 -Liver cancer

 -Breast cancer

 -Lung cancer

 -Cancer of the digestive tract

Besides the cancers listed above, this cancer test is sometimes positive in uterine fibroid, pregnancy, and liver disease.

·         CEA = carcinoembryonic antigen

·         As a cancer test, a CEA may be useful in diagnosing:

 -Colon cancer

 -Pancreatic cancer

 -Lung cancer

 -Breast cancer

 -Ovarian cancer

 -Thyroid cancer

Once again, some non-cancer causes of elevated CEA include smoking, hypothyroidism, and pregnancy.

Not all cancer tests are cancer tests.

By now, you should realize that a lab test might be used as a cancer test, but it might be used to diagnose other conditions as well. Some additional lab tests that can be used as cancer tests include:

·         Alpha-fetoprotein

 -Testicular cancer

 -Liver cancer

 -Ovarian cancer

·         HCG = Human chorionic gonadotropin

 -Testicular cancer

 -Ovarian  cancer

 -Liver cancer

 -Stomach cancer

 -Pancreatic cancer

 -Lung cancer

·          CA 19-9 

 -Colon cancer

 -Stomach cancer

 -Bile duct cancer

·         CA 15-3

 -Ovarian cancer

 -Prostate cancer

 -Lung cancer

·          CA 27-29

 -Colon cancer

 -Stomach cancer

 -Kidney cancer

 -Lung cancer

 -Pancreatic cancer

 -Uterine cancer

 -Liver cancer

But again, these tests may be indicated for something other than a cancer test.

Are cancer tests only done with blood samples?

In addition to blood tests for cancer testing, urine tests are also used.

Urinalysis

To obtain this test you will urinate (pee) into a specimen collection cup.

This test looks for blood in the urine, urine infection, and a few other things.

When used as a cancer test, if blood is found in your urine, your physician will do further testing to see if you have cancer of the:

-Kidney

-Ureter

-Bladder

-Urethra

As a non-cancer test, blood in the urine may simply indicate an infection of any of the structures just mentioned.

The next urine cancer test is:

Urine cytology

In this test, the doctor looks through a microscope to find cancer cells in the urine.

Potential cancer source:

-Kidney

-Ureter

-Bladder

-Urethra

While I have mentioned several cancer tests, these are not all the lab tests that can be done to detect cancer.

Go to these sites to learn more about lab cancer tests:

https://www.cancercenter.com/diagnosing-cancer/lab-tests

https://www.cancer.net

https://my.clevelandclinic.org/health/diagnostics/22338-blood-tests-for-cancer

How many cancer tests do you need?

“So, wait a minute,” you say. “Before you close this article, I have a question. If one positive cancer test doesn’t mean I have cancer, then more than one positive cancer test means I do have cancer, right?”

The answer is no, or at least, not necessarily. Let me explain with some good old-fashioned chicken and noodle soup.

Chicken and noodle soup

You are babysitting your young niece and nephew and you decide to make them some chicken and noodle soup using your grandmother’s recipe. So, you put all the ingredients in the pot with about a 50-50 mix of broth and noodles, etc. The soup smells delicious.

But, when you begin to dish it up, your niece says that she wants mostly broth because she doesn’t like “stuff” in her soup. Your nephew on the other hand wants mostly the chicken and noodles and not much broth because he doesn’t like “wet” chicken.

When you cooked the soup, the broth and “stuff” were balanced. But now the soup is unbalanced. This is what happens in your body to make your blood unbalanced or show up abnormal on lab tests.

Too much “stuff” or too much “wet”?

If you become dehydrated, then your blood is like your nephew’s bowl of soup, and you have more “stuff” in your blood because too much water left your body without being replaced.

On the other hand, if you swell from excess fluid, then you are like your niece’s bowl of soup because you have more fluid in your body which makes it look like you do not have enough “stuff” in your blood.

Now, let’s put this all together in a real-life example.

A real-life cancer test

You asked if you have more than one abnormal cancer test does that mean you have cancer. Here is one situation where this person has three abnormal lab values; but does she have cancer?

Jenn is at her doctor’s office to discuss her lab work. She has three positive cancer tests. She has a positive CA-125 test, which means she has ovarian cancer. Her RBCs are elevated indicating she has leukemia. And she has a lower-than-normal potassium level.

So, what kind of cancer does Jenn have?

Ready for the answer?

She doesn’t have cancer at all.

Jenn is pregnant which is why the CA-125 is elevated. The day before she had her bloodwork drawn, she had a stomach bug that gave her diarrhea. Because she lost so much fluid going to the bathroom, and because she was nauseated and didn’t feel like drinking, she had more “stuff” in her blood which caused her RBC count to be high (like your nephew’s bowl of soup). And lastly, there is a saying “where goes water, so goes potassium” so she lost potassium due to having diarrhea which caused her potassium level to go down.

The solution: give her a bowl of your grandmother’s chicken and noodle soup to replace fluids and potassium in her system and wish her a healthy pregnancy.

So, why does your doctor order cancer tests?

This article is in no way an exhaustive study of lab cancer tests. And let me reiterate that your doctor often orders lab tests to check for things other than cancer. But doctors also order lab tests for cancer tests.

So, the next time your physician orders lab tests, don’t assume you have cancer. And if your doctor is trying to find out if you do have cancer, expect to have some lab work done.

Comment below how this article has helped you better understand lab cancer tests.

Wishing you all the best,

Kelly

 Are your cancer screenings up to date?

Yes, I am a nurse. No, I am not your nurse. The medical topics discussed in this, or any article on this site, are intended to be issues for you to discuss with your medical team if you feel they apply to you. None of the information you are about to read in this article is treatment advice for you from me. I do not have that authority.