Although tumors are identified through imaging, a biopsy is needed to confirm the cancer type and to perform any other tests that may help the health care team decide how it will best be treated. A biopsy is a small piece of tissue that is taken from the original tumor or from a metastatic site. There are several different types of biopsies, and the type that is taken will depend on the type of cancer and where it is located. For example, a fine-needle aspirate is when a biopsy is taken with a needle. An excisional biopsy is one in which the tumor is cut out, which is common with skin cancers. Liquid biopsy is when a liquid sample is taken (blood, saliva, urine) and tested for cancerous cells; however, this type of biopsy is not yet commonly used, and many new tests using bodily fluids are still in development and have not yet been approved by the US Food and Drug Administration (FDA).

Biopsies are used to look at the cells of the cancer under the microscope and to do testing to diagnose the exact type of cancer that is present and sometimes to perform staging, which is important when determining how the cancer should be treated. In addition, the biopsy may be used for testing for gene mutations, which may be referred to as sequencing, mutational analysis, genetic testing, or genomic testing.

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Treatment and Prognostic Terms

There are many different types of treatments that are used for cancer, depending on the type and stage. For earlier-stage cancers, surgery is used to remove the tumor. In some cases, systemic treatment — when you take a drug, either orally, by injection, or via intravenous infusion, that affects the whole body — is also used. When systemic treatment is given before surgery, it is called neoadjuvant. When systemic treatment is given immediately after surgery, it is called adjuvant.

For patients with metastatic cancer, systemic therapy is often given alone without surgery. Health care providers may talk about the line of therapy, such as first-line (or frontline) or second-line therapy, which refers to the order of systemic therapies. The first type of treatment given is first-line therapy, and if the cancer does not respond or stops responding, the second type of treatment is called a second-line treatment. Sometimes patients will be given maintenance therapy after their initial treatment, which is to help maintain the response to the original therapy for a longer period of time. There are several major types of therapies used systemically and these include chemotherapy, targeted therapy, hormone therapy, and immunotherapy.

Some patients will receive radiation therapy in addition to surgery and/or systemic treatment. Radiation refers to a type of high-energy particles or waves that are targeted to a tumor or an area where the tumor was located prior to surgery to kill any additional cancer cells. External radiation is when the radiation is given by a machine that is outside the body, whereas internal radiation, or brachytherapy, is when radioactive material is implanted in the body. Image-guided radiation uses some type of imaging, such as ultrasound or MRI, to guide where the radiation beam should be targeted. Intensity-modulated radiation is when the beam of external radiation is shaped to more closely resemble the shape of the tumor.