A member of the Seattle Cancer Care Alliance Network

Cancer Diagnosis and Tests

Cancer diagnostic tests determine if someone has cancer, the kind of cancer it is, and if it's located in more than one area of the body. You may have follow-up tests after your initial diagnosis to learn more about your cancer and how fast or slowly it is growing.

Your cancer doctors want to have as much information as possible before discussing treatment with you, and these tests are a necessary part of that process.

Common Diagnostic Tests

Diagnostic tests might be done at a medical clinic, in a lab, or at a hospital. For some tests, the patient is under anesthesia or sedated. The most common types of diagnostic tests are:

Imaging tests:

  • Diagnostic mammograms
  • Magnetic resonance imaging (MRI)
  • Computerized tomography (CT scans)
  • X-rays
  • Ultrasound

These tests take a picture (image) of organs, bones, or other tissue as the patient lies very still, positioned either below or beside an imaging machine. A radiologist and/or cancer specialist look at the images. They confirm if a cancer tumor is present, find out more information about the tumor, and determine if it has spread to other parts of the body.  

Lab tests: A sample of blood, urine, or tissue is checked for certain features that show if cancer is present. These tests can be used for screening or as a follow-up diagnostic test. Often, after a lab test, a biopsy (a tissue sample) is needed.

Biopsy: A biopsy helps diagnose cancer by taking a sample of tissue or fluid. A biopsy can be done with a needle or in surgery, depending on the type of cancer and where it’s located. A pathologist (a doctor who specializes in studying tissue) looks at the sample under a microscope to see if it contains cancer cells or to find out more about the specific cancer.

A flexible tube with a tiny camera is guided into the mouth, digestive tract, lungs, or urinary tract. This is done to detect growths and to remove abnormal tissue for testing by a pathologist.  

Colonoscopy: A flexible lighted tube is used to examine the inner lining of the rectum and colon, and to remove growths. A pathologist will examine these growths for cancer.

Next Steps

At Group Health, you will usually get the results of your diagnostic test from the doctor who referred you for these tests, from the doctor who performed them, or from our Breast Imaging Center. When you get your test, feel free to ask how you will get the results — and let us know the best way to get in touch with you.

If the results show that you have cancer, your doctor will talk to you about the next steps. Those could be more diagnostic tests or talking about treatment options.

If additional testing reveals more about a specific cancer (after initial diagnosis), the next step would usually be discussing your treatment options.

We encourage you to take time to think about what treatment or treatments your cancer specialist recommends. A family member or close friend can help ask questions and take notes at an appointment with you. You and your cancer doctor will work together, at a level you are comfortable with, to decide your treatment choices.

Second Opinion

Some patients want a second opinion to confirm the diagnosis and treatment plan, or suggest changes to it. You can have a second opinion from a different cancer doctor at Group Health Medical Centers, or from someone outside Group Health who is part of your health plan provider network. Your doctor can refer you to someone for a second opinion, or you can choose who to see. If you aren’t sure about your health plan benefits, call Customer Service.

After your second opinion, check back with your Group Health doctor via office visit, phone, or MyGroupHealth secure messages. You and your doctor can confirm or reconsider your plan and discuss where you will get your treatment.

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