• Also Known As:
  • Malignancy
  • Malignant tumor
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What is cancer?

Cancer is a disease in which cells in a part of the body become abnormal and grow uncontrollably. Cancerous cells do not go through the natural stages of growth, division, and dying that normal cells do. They multiply unchecked and may form one or more masses of cells (tumors). Tumors can damage healthy tissue and grow large enough to interfere with body functions. However, not all cancers form tumors (e.g., leukemia) and not all tumors are malignant—some are benign (non-cancerous and non-spreading).

Cancer can eventually spread (metastasize) beyond the site of origin into nearby lymph nodes, tissues, and other organs. There are many types of cancer and they are often named according to location in the body where they originate.

Various lab tests are used in the screening, diagnosis, and management as well as the risk assessment of cancer. However, not all types of tests are available for all types of cancer. Below are listed some examples of these types of tests:

  • Risk assessment—determining whether an individual has a high risk for a particular type of cancer; examples include BRCA mutation for breast and ovarian cancer risk and HPV for cervical cancer risk
  • Screening—detecting cancer before symptoms appear; examples include Pap test for cervical cancer
  • Diagnosis—examples include BCR/ABL mutation to help diagnose chronic myelogenous leukemia (CML) or a type of acute lymphoblastic leukemia (ALL) and JAK2 to help diagnose myeloproliferative neoplasms.
  • Treatment—helping to guide the selection of drugs to treat cancer or monitoring effectiveness of treatment; example include HER2/neu to determine whether a woman’s breast cancer will respond to the drug trastuzumab and BCR/ABL to monitor treatment of leukemia

Not all types of cancer are covered on Lab Tests Online, but there are numerous web resources available, some specific to certain types of cancer and others that provide more general information on cancer (see Additional Resources below).

Articles on specific types of cancer 
Breast cancer Melanoma
Cervical cancer Multiple myeloma
Colorectal cancer Myeloproliferative neoplasms
Leukemia Ovarian cancer
Liver cancer Pancreatic cancer
Lung cancer Prostate cancer
Lymphoma Testicular cancer
Waldenstrom Macroglobulinemia Thyroid cancer

Other articles on Lab Tests Online that cover cancer-related topics:


This graph shows the number of new U.S. cancer cases and deaths each year per 100,000 persons by race/ethnicity and sex. Image credit: National Cancer Institute


Leading-edge Research

Research is ongoing into new tests and treatments for cancer. For example, new research has shown that most people with waldenstrom macroglobulinemia (WM) have cancer cells with MYD88 gene mutations. A smaller percentage of WM patients have CXCR4 gene mutations. Scientists are looking into developing new treatments that target these mutations. For more on these, visit the International Waldenstrom’s Macroglobulinemia Foundation website. For more on what’s new in cancer, see the links below in Patient Resources.

Additional Resources

Patient Stories

The views expressed in these articles are those of the source and do not necessarily reflect the views of Lab Tests Online or the Lab Tests Online Editorial Review Board.

Peter DeNardis – There is Life with Waldenstrom’s

Adapted from the full article appearing on the Stories of Hope page of the International Waldenstrom’s Macroglobulinemia Foundation (IWMF) web site.

“Get your affairs in order. You have a rare, incurable blood cancer called Waldenstrom’s macroglobulinemia. Average survival rate is 6 years. Given your symptoms and blood test values, we have to treat immediately.” Those were jarring words for someone in his early 40s, married, and with three children ranging in ages from 7 to 16.

Read his full story of hope.


Michael Smith Cancer SurvivorMichael J. Smith: 22 Years and Counting – My Cancer Journey

Adapted from the full article appearing on the Stories of Hope page of the International Waldenstrom’s Macroglobulinemia Foundation (IWMF) web site.

The following is an account of a life journey with Waldenstrom’s Macroglobulinemia (WM) that later turned into WM with Lymphoma (WM/L) – categorized in my medical file as “restaging of diagnosed WM with transformation into diffuse large B-cell lymphoma (DLBCL).” My story is aimed at beginning patients, so I will cover the WM episode more thoroughly than the subsequent WM/L. Full disclosure: I am only a novice in medicine, so I may have occasionally included errors in my treatment. Consequently, I have omitted my doctors’ names to avoid having any of these errors attributed to them. [For more information, see the IWMF page What is WM? and the detailed guide on the American Cancer Society’s site.]

As with many WM’ers, there was a telltale indicator that my WM began well before it was formally diagnosed. Buried in my internist’s blood work report in June of 1994 was the fact that my Erythrocyte Sedimentation Rate (ESR) was 83.3 mm/hr – way too high – when it should have been in the range 0 – 15 mm/hr. [An ESR is a non-specific test for inflammation. It can indicate that inflammation is occurring somewhere in the body but cannot determine where or what is causing it. For more, see the ESR article.]

My internist didn’t have a reason for it, and I swiftly buried it within the cobwebs of my mind as I had another more pressing problem. I had a cancer – more specifically Acinic Cell Carcinoma – in my left parotid gland (a salivary gland), and I needed to take care of it immediately. This was operated on in July, followed by radiation treatments a month later. The problem has not recurred since, although some symmetry has been lost in my facial features. Unbeknownst to me, it was the beginning of interweaving threads of curable and incurable cancers in my life. Read his full story of hope.

Provider Perspective

The views expressed in these articles are those of the source and do not necessarily reflect the views of Lab Tests Online or the Lab Tests Online Editorial Review Board.

Understanding Cancer Diagnostic Blood Tests
Source: Patient Power

Transcript of Video

Tamara Lobban-Jones:

Hello and welcome to this Ask the Expert webinar, “Understanding Cancer Diagnostic Blood Tests.” My name is Tamara Lobban-Jones. We’ve received your questions, and we’re going to do our best address them.

Our featured guest has taught hospital training programs, graduate programs, medical school students all over the world. In her 35 years as a professor, she has taught over 10,000—yes, you heard me right—10,000 non-science majors, and she also serves as Editor-in-Chief at the American Society of Clinical Laboratory Science taking time out of her busy schedule to personally answer dozens upon dozens of questions submitted by patients daily.

Dr. Leclair:

It’s a privilege to talk to everybody today, Tamara. Thank you.

Tamara Lobban-Jones:

Dr. Leclair, in our ongoing lab test series featured on Patient Power, we’ve learned about dozens of cancer diagnostic blood tests, and there are various things that the values are impacted by, whether it’s dehydration, running up and down stairs, extracurricular activities, these can cause the values to fluctuate. And I know we’ve also—you’ve also taught us that timing is everything.

Can you give us a brief overview of the cancer diagnostic tests you use today and kind of help us understand why they’re so critical to a cancer diagnosis?

Dr. Leclair:

Okay. That’s a good three-credit course in graduate school, but we’re going to try and do this a little bit more tersely. Try and think of laboratory tests in three different levels. The first level would be introductory or screening test. The second one would be more of a let’s follow this down for a little bit, see where it leads us. And then finally, typically the more expensive, the actual diagnostic tests.

So if we start with that first bunch, the general screening, we’ve all had them, we all know them to a certain extent, and that would be things like a common liver panel or the common metabolic a panel that you might have in a chemistry setting or a CDC. And the things that a physician is looking for generally at that level is, is there anything that looks really odd? Is there something that I need to really look at more closely?

For example, a lowered white cell count or a lowered hemoglobin count or an increased enzyme in the chemistries would cause a physician to say, gee, do I have an explanation for this? Oh, yes, they have a viral disease. Oh, yes, they had recent surgery, something like that. Can I explain these anomalies? If I can’t, then I need to go to slightly more specific second-level kinds of tests.

And the one probably that everybody knows the most about is LD, lactic dehydrogenase. It’s an enzyme that’s found in every cell in the body. It should be inside the cell, not in the bloodstream. But if there’s a lot of cell turnover, if there’s a lot of cell damage or death, then more of it’s going to leak out into the bloodstream, and that would be an indicator to a physician that something somewhere is definitely going on. You have to look further or more deeply into the situation. So you’ve got screening tests and then secondary tests.

And then finally you’ve got typically the ones that take the longest, typically the ones that are the most expensive, typically the ones that most people are nervous about, which would be the genetic tests or the flow cytometry tests or tests that are specific for maybe only three or four different kinds of diseases. So you have to kind of think about these in terms of layers of thinking or of process.

Please remember the opinions expressed on Patient Power are not necessarily the views of our sponsors, contributors, partners or Patient Power. Our discussions are not a substitute for seeking medical advice or care from your own doctor. That’s how you’ll get care that’s most appropriate for you.