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Can You Have Cancer With Normal Blood Counts?
Blood tests constitute one element in the detection of cancer and other diseases. Blood test results that differ substantially from normal ranges give your doctor valuable information that will help her understand your health situation better. Normal blood test results have a similar informative value. But no single blood test result clearly indicates that you do or do not have cancer. You can have cancer with normal blood counts.
Why Your Doctor Orders Blood Tests
As the Mayo Clinic has noted, your doctor may order cancer blood tests for several reasons, one of them being to determine how well your organs function. Note also that your doctor cannot detect certain cancers with blood tests. Prostate cancer, for example, if confined to the prostate, will probably not show up in one common blood test, the Complete Blood Count test, and may not show up even in a PSA (Prostate-Specific Antigen) test 2. Your doctor will recommend at least one further test, usually a needle biopsy, before a determination of prostate cancer. A needle biopsy is a relatively painless test that your doctor will normally perform in his office.
- As the Mayo Clinic has noted, your doctor may order cancer blood tests for several reasons, one of them being to determine how well your organs function.
Complete Blood Count (CBC)
Blood Tests That Show Cancer
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One commonly used blood test, the CBC test, will reveal the comparative amounts of different blood cells in a blood sample. If you have too many or too few cells of certain types of blood cells, this suggests to your doctor that you should have further diagnostic tests, such as a bone marrow biopsy. By itself, a CBC test does not confirm that you do not have cancer, even for those cancers that commonly show up in a blood sample.
- One commonly used blood test, the CBC test, will reveal the comparative amounts of different blood cells in a blood sample.
- If you have too many or too few cells of certain types of blood cells, this suggests to your doctor that you should have further diagnostic tests, such as a bone marrow biopsy.
Blood Protein Test
Another common blood test, blood protein testing, can help your doctor by detecting abnormal proteins, or immunoglobulins. Persons with elevated immunoglobulin levels may have multiple myeloma. But a person may have an elevated immunoglobulin level for other reasons. In the presence of other factors associated with cancer, even if you have normal blood protein you will need additional tests
- Another common blood test, blood protein testing, can help your doctor by detecting abnormal proteins, or immunoglobulins.
- Persons with elevated immunoglobulin levels may have multiple myeloma.
Other Tests
What May Cause Too Much Protein in Blood?
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After blood tests that confirm abnormal cells, abnormal blood counts or abnormal immunoglobulin levels, your doctor will order additional tests before concluding that you have a particular cancer. Urine cytology (basically a urine sample examination) may reveal cancers specific to the bladder, urinary tract or kidneys. Tumor marker tests will also help confirm or reject cancer hypotheses. But tumor marker tests do not give definitive results either. Like a detective, your doctor assembles evidence that cumulatively leads her toward a diagnosis. No single diagnostic test can determine the presence or absence of cancer.
- After blood tests that confirm abnormal cells, abnormal blood counts or abnormal immunoglobulin levels, your doctor will order additional tests before concluding that you have a particular cancer.
- Urine cytology (basically a urine sample examination) may reveal cancers specific to the bladder, urinary tract or kidneys.
Second Opinions
Even if your doctor concludes that you do or do not have a particular cancer, you may want to seek a second opinion from another group of doctors or cancer center. Often a different medical staff will want to run the same tests, including blood tests again. Different laboratories can come to different conclusions. Also, a second specialist in reading stains (visual replications of biopsies), even if he concludes that you do have the cancer previously diagnosed, may interpret the results differently, leading a second staff to recommend a different course of treatment.
- Even if your doctor concludes that you do or do not have a particular cancer, you may want to seek a second opinion from another group of doctors or cancer center.
- Also, a second specialist in reading stains (visual replications of biopsies), even if he concludes that you do have the cancer previously diagnosed, may interpret the results differently, leading a second staff to recommend a different course of treatment.
Related Articles
References
- MayoClinic: Cancer blood tests: Lab tests used in cancer diagnosis
- MedicineNet.com: Complete Blood Count (CBC)
- Stanford Cancer Center: Cancer Diagnosis
- Stanford Medicine. Diagnosis. Stanford Health Care. Updated November 2019.
- WHO - Cancer. Early Detection Of Cancer. World Health Organization. Published January 2016.
- The University of Texas MD Anderson Cancer Center. Diagnostic Tests. MD Anderson Cancer Center - Diagnosis and Treatment. Published April 2019.
- Fetterman A, Haldeman-Englert C. Urine Cytology. Health Encyclopedia - University Of Rochester Medical Center. Updated November 2019.
- The American Cancer Society Medical and Editorial Content Team. How Is Cancer Diagnosed?. American Cancer Society. Updated July 2015.
- American Cancer Society. Testing Biopsy And Cytology Specimens For Cancer. Exams and Tests for Cancer. Updated December 2019.
- Levin M, LoCicero L, Sather S. Cancer Diagnostic Imaging. Health Encyclopedia - University Of Rochester Medical Center. Updated November 2019.
- The American Cancer Society Medical and Editorial Content Team. Ultrasound For Cancer. American Cancer Society. Updated November 2015.
- Centers for Disease Control and Prevention (CDC). What Is A Mammogram? CDC Division of Cancer Prevention and Control. Updated September 2018.
- The American Cancer Society Medical and Editorial Content Team. Nuclear Medicine Scans For Cancer. American Cancer Society. Updated August 2019.
- Centers for Disease Control and Prevention (CDC). Cancer Screening Tests. CDC Division of Cancer Prevention and Control. Published July 2019.
- American Cancer Society. Cancer Prevention & Early Detection Facts & Figures 2019-2020. Atlanta: American Cancer Society; 2019.
- Centers for Disease Control and Prevention (CDC). What Is Screening For Prostate Cancer? CDC Division of Cancer Prevention and Control. Updated July 2019.
- Centers for Disease Control and Prevention. What Screening Tests Are There For Skin Cancer? CDC Division of Cancer Prevention and Control. Updated June 2019.
- Plüddemann A, Heneghan C, Thompson M, Wolstenholme J, Price CP. Dermoscopy for the diagnosis of melanoma: primary care diagnostic technology update. Br J Gen Pract. 2011;61(587):416-417. doi:10.3399/bjgp11X578142
- National Cancer Institute. What Cancer Screening Statistics Really Tell Us. U.S. Department of Health and Human Services, National Institutes of Health, National Cancer Institute. Updated July 2018.
- National Cancer Institute. Screening For Cancer. U.S. Department of Health and Human Services, National Institutes of Health, National Cancer Institute. Updated April 2018.
- National Cancer Institute. How Cancer Is Diagnosed. U.S. Department of Health and Human Services, National Institutes of Health, National Cancer Institute. Updated July 2019.
- National Cancer Institute. Understanding Laboratory Tests Fact Sheet. U.S. Department of Health and Human Services National Institutes of Health, National Cancer Institute. Updated December 2013.
Writer Bio
Patrick Gleeson received a doctorate in 18th century English literature at the University of Washington. He served as a professor of English at the University of Victoria and was head of freshman English at San Francisco State University. Gleeson is the director of technical publications for McClarie Group and manages an investment fund. He is a Registered Investment Advisor.