How do doctors test for cancer?

Question

I was wondering if they can tall if someone has cancer from blood tests.

Answer 1

Yes, some forms of cancer can be detected by blood tests.

Answer 2

Usually blood tests are used in addition to a physician's history and physical examination to confirm his diagnosis. There is not one blood test for all cancers.

There are certain hormones that can be elevated if you have a particular cancer but these are only used to aid in the diagnosis. Also, you can have a complete blood count which often would show if you have a blood disorder like leukemia. For instance, if you have liver cancer, your liver enzymes would be abnormal, but liver enzymes can be elevated in many other conditions as well. This is why results need to be combined with signs and symptoms for a more accurate diagnosis. Also, once one is diagnosed with cancer, depending on the type, blood work is monitored closely for changes from your baseline blood work as this can signify a change in your status. Let me give you an example. The PSA (prostate specific antigen) level is not used as a diagnosis of Prostate cancer, but if you are diagnosed with Prostate cancer and go into remission, your PSA level will be monitored periodically (usually yearly) and if it increases significantly from your last PSA level it would suggest that the cancer has returned.

Really lab work does not provide a definitive answer, it is always in addition to an examination of your signs and symptoms. It is like putting together all the pieces of a puzzle. Lab work is only one tiny bit of the puzzle.

Answer 3

Most cancers are initially recognized either because signs or symptoms appear or through screening. Neither of these lead to a definitive diagnosis, which usually requires the opinion of a pathologist.

Roughly, cancer symptoms can be divided into three groups:

1. Local symptoms: unusual lumps or swelling (tumor), hemorrhage (bleeding), pain and/or ulceration. Compression of surrounding tissues may cause symptoms such as jaundice.
2. Symptoms of metastasis (spreading): enlarged lymph nodes, cough and hemoptysis, hepatomegaly (enlarged liver), bone pain, fracture of affected bones and neurological symptoms. Although advanced cancer may cause pain, it is often not the first symptom.
3. Systemic symptoms: weight loss, poor appetite and cachexia (wasting), excessive sweating (night sweats), anemia and specific paraneoplastic phenomena, i.e. specific conditions that are due to an active cancer, such as thrombosis or hormonal changes.
Every single item in the above list can be caused by a variety of conditions (a list of which is referred to as the differential diagnosis). Cancer may be a common or uncommon cause of each item

Blood test results may give a doubt in case of some cancers but it is not the ultimate test.

Answer 4

No, not all blood tests show up cancer. I you think you have cancer speak to you Doctor and they can send you for x-rays or discuss what type you think you have.

Answer 5

Detection
Direct or assisted visual observation is the most widely available examination for the detection of cancer. It is useful in identifying suspicious lesions in the skin, retina, lip, mouth, larynx, external genitalia, and cervix.

The second most available detection procedure is palpation to detect lumps, nodules, or tumors in the breast, mouth, salivary glands, thyroid, subcutaneous tissues, anus, rectum, prostate, testes, ovaries, and uterus and enlarged lymph nodes in the neck, axilla, or groin.

Internal cancers require procedures and tests such as endoscopy, x-rays, magnetic resonance imaging, or ultrasound. Laboratory tests, such as the Pap smear or the fecal occult blood test have been employed for detection of specific cancers.

The performance of screening tests is usually measured in terms of sensitivity, specificity, and positive-predictive values (PPV) and negative-predictive values (NPV). Sensitivity is the chance that a person with cancer has a positive test. Specificity is the chance a person without cancer has a negative test. PPV is the chance that a person with a positive test has cancer. NPV is the chance that a person with a negative test does not have cancer. PPV and, to a lesser degree, NPV are affected by the prevalence of disease in the screened population. For a given sensitivity and specificity, the higher the prevalence, the higher the PPV.

http://www.cancer.gov/cancerinfo/pdq/screening/overview#Section_15








Peace.

Answer 6

To my knowledge blood test can detect certain forme of cancer, leukimia, liver etc.
Otherwise, byopsie of the parts concern can reveal if there is cancer.

Answer 7

It absolutely relies on the variety of cancer. Some possibilities comprise: Imaging stories like X-Ray, ultrasound, CT, MRI, PET... Blood work, biopsies, tissue samples, fluid samples... Endoscopy, laproscopy, colonoscopy, colposcopy... There are a lot of extra. In case you have any issues, you should see a medical professional. Early detection is vital with any melanoma.

Answer 8

Depends on the cancer. My husband had testicular cancer, and it elevates something in your blood(can't remember the name right now). They also did a PET scan. If they know what they're looking for, there's more options.

Answer 9

Well sometimes they see something abnormal in the blood and then they will do a certain test to see what it is, and then they can do a full body scan to see where it is......so yes.

Answer 10

No, not always.