Patient Guide to Tumor Markers

Author: Carolyn Vachani RN, MSN, AOCN
Content Contributor: Katherine Okonak, MSW, LSW
Last Reviewed: February 28, 2024

Key Takeaways:

  • Tumor markers are substances found in the blood. Tumor marker levels may be higher when there is cancer in the body.
  • They are not very “specific,” meaning non-cancer health issues can also cause these levels to be higher.
  • They must be used along with radiology tests and exams by your healthcare provider.

What is a tumor marker?

Tumor markers may also be called cancer markers or biomarkers. A tumor marker is a substance found in the blood, urine, stool, the tumor itself, or tissue. The level of the tumor marker and which one it is can help you and your provider learn about your cancer. Some of these markers are specific to one cancer and others are seen in many types of cancer. Other non-cancer health issues can also cause these levels to be higher.

What are tumor markers used for?

Tumor markers are often used to track how well your cancer treatment is working. If the level is going down, it may mean the treatment is working. If it is going up, the cancer may be growing. Health issues other than cancer can cause markers to be higher. So, they are used along with imaging (CT scan, MRI, Ultrasound), your symptoms, and your healthcare provider’s exam to see how your cancer is reacting to treatment.

In some cancers, markers are used to watch for recurrence (return of the cancer after treatment). This is not useful in all cancer types. In breast cancer, research has found that watching tumor markers after treatment does not help people live longer. For that reason, they are not recommended.

Tumor markers can also be used along with other tests (like scans and biopsies) to help find, diagnose, and stage cancer if you have symptoms that could be caused by cancer. Some markers can help predict how you will do and guide your treatment plan.

Can a tumor marker be used to screen for cancer?

Ideally, markers could be used as a screening test for the general public. The goal of a screening test is to find cancer early when you don’t have symptoms, when it is the most treatable, and before it has grown and spread. So far, the only tumor marker used as a screening tool is the Prostate Specific Antigen (PSA) for prostate cancer, though this has concerns as well.

The main worry with tumor markers is that they are not specific enough – they have too many false positives. This means that the level is high even when there is no cancer. This leads to costly tests that are not needed and can cause patients to worry. The other concern is that the marker level is not high in the early stages of the cancer, so the cancer cannot be found any earlier than when symptoms start. Also, some substances used as tumor markers are normally made in the body, and a “normal” level is not always zero.

Does every cancer type have a tumor marker?

There is not a known tumor marker for all types of cancer. Even if a cancer type has a tumor marker, the level may not be high, so they are not helpful for all patients. For example, carcinoembryonic antigen (CEA) is a tumor marker used in colon cancer, yet only 7 to 8 out of 10 colon cancers make CEA. This means up to 3 out of 10 people with colon cancer will not have a high CEA level. Only 1 out of 4 early stage colon cancers have a higher than normal CEA. Because of this, CEA cannot always help find colon cancer in its early stages, when cure rates are best.

Tumor markers can be very helpful in watching your response to treatment and, in some cases, watching for the cancer to return. However, they need to be used along with your healthcare provider’s exam, any symptoms you are having, and radiology studies (CT scan, MRI, PET, and so on).

Guide to Tumor Markers Used in Cancer

This is a table of the most often used tumor markers, the cancers they can be found with, non-cancerous health issues that can cause them to be high, and the range of normal results.

In cases where the half-life is listed, this should be kept in mind when checking levels. For example, the PSA half-life is 2-3 days, so if the level were checked the day after surgical removal of the prostate, it would still be raised. If the level were checked a week later, the result should be zero, or very close to zero, if no prostate cells remain.

Tumor MarkerCancers Associated With Elevated ResultsNon-Cancerous Reasons for Elevated Levels"Normal" Results
Blood test (blood serum marker), except where noted.(**) indicates the most common association, if one exists Different labs may have different high/low values
Germ cell cancers of ovaries & testes** (Non-seminomatous, particularly embryonal and yolk sac, testicular cancers).
Some primary liver cancers (hepatocellular)
Pregnancy (clears after birth), liver disease (hepatitis, cirrhosis, toxic liver injury), inflammatory bowel diseaseLow levels present in both men & non-pregnant women (0-15 IU/ml); generally, results >400 are caused by cancer (Half-life 4-6 days)
Bence-Jones Proteins
(urine test)
Monoclonal Immunoglobulins (blood test)
Multiple Myeloma** Waldenstrom's macroglobulinemia, chronic lymphocytic leukemiaAmyloidosisGenerally, a value of 0.03-0.05 mg/ml is significant for early disease
Multiple myeloma**, chronic lymphocytic leukemia (CLL), and some lymphomas (including Waldenstrom’s macroglobulinemia)Kidney disease, hepatitis< 2.5 mg/L
Bladder Tumor Antigen
(urine test)
Bladder cancer**,
cancer of kidney or ureters
Invasive procedure or infection of bladder or urinary tractNone normally detected
CA 15-3
Cancer Antigen 15-3 or Carbohydrate Antigen 15-3
Breast** (often not elevated in early stages of breast cancer), lung, ovarian, endometrial, bladder, gastrointestinalLiver disease (cirrhosis, hepatitis), lupus, sarcoid, tuberculosis, non-cancerous breast lesions< 31 U/ml (30% of patients have an elevated CA 15-3 for 30-90 days after treatment, so wait 2-3 months after starting new treatment to check)
CA 19-9
Cancer Antigen 19-9 or Carbohydrate Antigen 19-9
Pancreas** and colorectal, liver, stomach and biliary tree cancersPancreatitis, ulcerative colitis, inflammatory bowel disease, inflammation or blockage of the bile duct, thyroid disease, rheumatic arthritis< 37 U/ml is normal
> 120 U/ml is generally caused by tumor
CA 125
Cancer Antigen 125 or Carbohydrate Antigen 125
Ovarian cancer** breast, colorectal, uterine, cervical, pancreas, liver, lungPregnancy, menstruation, endometriosis, ovarian cysts, fibroids, pelvic inflammatory disease, pancreatitis, cirrhosis, hepatitis, peritonitis, pleural effusion, following surgery or paracentesis0-35 U/ml
CA 27.29
Cancer Antigen 27.29 or Carbohydrate Antigen 27.29
Breast** (best used to detect recurrence or metastasis).
Colon, gastric, liver, lung, pancreatic, ovarian, prostate cancers
Ovarian cysts, liver and kidney disorders, non-cancerous (benign) breast problems< 40 U/ml Generally, levels > 100 U/ml signify cancer (30% of patients have elevated CA 27.29 for 30-90 days after treatment, so wait 2-3 months after starting new treatment to check)
CalcitoninMedullary thyroid cancer**Chronic renal insufficiency, Chronic use of Proton-pump inhibitors (medications given to reduce stomach acid)<8.5 pg/mL for men
< 5.0 pg/mL for women
Carcinoembryonic Antigen
Colorectal cancers ** Breast, lung, gastric, pancreatic, bladder, kidney, thyroid, head & neck, cervical, ovarian, liver, lymphoma, melanomaCigarette smoking, pancreatitis, hepatitis, inflammatory bowel disease, peptic ulcer disease, hypothyroidism, cirrhosis, COPD, biliary obstruction<2.5 ng/ml in non-smokers <5 ng/ml in smokers Generally, > 100 signifies metastatic cancer
Chromogranin ANeuroendocrine Tumors**, carcinoid tumors, neuroblastoma, and small cell lung cancerProton-pump inhibitors (medications given to reduce stomach acid)Normal varies on how tested, but typically < 39 ng/l is normal
Cytokeratin Fragment 21-1
(Blood Test)
Lung, urologic, gastrointestinal, and gynecologic cancersLung disease0.05-2.90 ng/ml
Human Chorionic Gonadotrophin
Or Beta-HCG, B-HCG
Germ cell, testicular cancers**, gestational trophoblastic neoplasiaPregnancy, marijuana use, hypogonadism (testicular failure), cirrhosis, inflammatory bowel disease, duodenal ulcersIn men: < 2.5 U/ml
In non-pregnant women: < 5.0 U/ml
5-Hydroxy-Indol Acetic Acid
(24 hour urine collection)
Carcinoid tumorsCeliac & tropical sprue, Whipple's disease, dietary: walnuts, pecans, bananas, avocados, eggplants, pineapples, plums & tomatoes; medications: acetaminophen, aspirin and guaifenesinNormal 6-10 mg over 24 hours
Lactic Dehydrogenase
Lymphoma, melanoma, acute leukemia, seminoma (germ cell tumors)Hepatitis, MI (heart attack), stroke, anemia (pernicious & thalassemia), muscular dystrophy, certain medications (narcotics, aspirin, anesthetics, alcohol), muscle injuryNormal values are 100-333 u/l
Neuron-specific Enolase
Small cell lung cancer**, neuroblastomaProton pump inhibitor treatment, hemolytic anemia, hepatic failure, end stage renal failure, brain injury, seizure, strokeNormal < 9 ug/L
NMP 22
(urine test)
Bladder cancer**BPH (benign prostatic hypertrophy), prostatitisNormal < 10 U/ml
Prostatic Acid Phosphatase
Metastatic prostate cancer**
Myeloma, lung cancer, osteogenic sarcoma
Prostatitis, Gaucher's disease, osteoporosis, cirrhosis, hyperparathyroidism, prostatic hypertrophyNormal : 0.5 to 1.9 u/l
Prostate Specific Antigen
Prostate**BPH (benign prostatic hypertrophy), nodular prostatic hyperplasia, prostatitis, prostate trauma/ inflammation, ejaculationNormal < 4 ng/ml (half life 2-3 days)
Thyroid CancerAnti-thyroglobulin antibodies< 33 ng/mL; if entire thyroid removed
< 2 ng/mL
Urine Catecholamines:
Vanillylmandelic Acid
(24 hour collection of urine; it is a catecholamine metabolite)
Neuroblastoma** Pheochromocytoma, ganglioneuroma, rhabdomyosarcoma, PNETDietary intake (bananas, vanilla, tea, coffee, ice cream, chocolate), medications (tetracyclines, methyldopa, MAOIs)8 – 35 mmols over 24 hours
Homovanillic Acid
(24 hour collection of urine; it is a catecholamine metabolite)
Neuroblastoma**Same as VMA, in addition: psychosis, major depression, dopamine (a medication)Up to 40 mmols over 24 hours

Tumor markers can be helpful when going through treatment for cancer. Ask your provider if there are tumor markers that they will be tracking while you are going through treatment and what the results mean.

Abeloff, M., Armitage, J., Niederhuber, J., Kastan, M. & McKenna, G. (Eds.): Clinical Oncology (2004). Elsevier, Philadelphia , PA.

Cleveland Clinic. Tumor Markers. 2023.

Duffy MJ. Tumor markers in clinical practice: a review focusing on common solid cancers. Med Princ Pract. 2013;22(1):4-11.

Febbo PG, Ladanyi M, Aldape KD, De Marzo AM, Hammond ME, Hayes DF, Iafrate AJ, Kelley RK, Marcucci G, Ogino S, Pao W, Sgroi DC, Birkeland ML. NCCN Task Force report: Evaluating the clinical utility of tumor markers in oncology. J Natl Compr Canc Netw. 2011 Nov;9 Suppl 5:S1-32; quiz S33.

National Cancer Institute. Tumor Markers. 2023.

Perkins GL, Slater ED, Sanders GK, Prichard JG. Serum tumor markers. Am Fam Physician 2003;68:1075-82.

Sanchez Yamamoto D, Hallquist Viale P, Roesser K, Lin A. The clinical use of tumor makers in select cancers: are you confident enough to discuss them with your patients? Oncol Nurs Forum 2005;32:1013-22; quiz 1023-4.

Sturgeon, CM, Lai LC, Duffy MJ. Serum tumour markers: how to order and interpret them. BMJ. 2009; 339:852-858

Vaidyanathan K, Vasudevan DM. Organ Specific Tumor Markers: What's New? Indian J Clin Biochem. 2012;27(2):110-20.

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