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What to Know About Your Treatment Choices for Carcinoma of Unknown Primary Origin

Woman talking with a female doctor

Researchers are continually finding new treatments for carcinoma of unknown primary origin (CUP). You now have more hope for survival than ever before. In this section, we’ll cover the details of different treatments and how each one might work.

Because a cancer of unknown primary site can be any one of many different cancers, there is not one standard way to treat it. The treatment your doctor recommends for you depends on where it is considered most likely that the cancer started from, the size and location of the tumor or tumors, the results of your lab tests, and the stage or extent of the cancer. Your doctor also considers your age and general health when making recommendations about a treatment. Today there are more ways than ever before, including genetic analysis, to determine the likely origins of CUP. The closer your doctor can get to determining where the cancer came from, the more likely that the treatment will be most effective. 

You are likely to have many questions and concerns about the treatment options. Learn all you can about the cancer and your treatment choices. That way, you’ll be able to take an active part in decisions about your care.

Your doctor is the best person to answer questions about treatment, such as what the choices are, how well they might work, and what the risks and side effects may be. You may want to know how you might have to change your normal activities. You may want to talk with your doctor about the goal of treatment. Sometimes, even if a cure is not possible, treatment may improve your quality of life and help you live longer. You may want to consider the possible side effects of treatment as well as the possible benefits.

It can be tough to decide on a treatment for CUP. It might help to have the opinion of more than one doctor. Before starting any treatment, you may want to talk to a second doctor about his or her recommendation for both diagnosis and treatment. Taking time to make an informed decision about the best treatment options most likely will not hurt your chance of the treatment working.

Remember, it is not as important to make a quick decision as it is to make an informed one. It may take two or three weeks to get an accurate result from some of the tests. You should get all the information you can to help make an informed decision. It will also help you learn what to expect from treatment and the cancer care team.

Types of treatment for CUP

Treatment for CUP is only undertaken after an exhaustive search for a primary cancer. This typically includes full body imaging with CT or PET/CT scans, blood tests for tumor markers, and other tests such as recently available tests that analyze genetic mutations in the cancer in order to seek out a likely primary cancer. 

When no primary cancer can be found, treatment for CUP may be either local, systemic, or a combination of both. Local treatments remove, destroy, or control cancer cells in one certain area. Radiation and surgery are local treatments. Systemic treatments are used to destroy or control cancer cells throughout your entire body. Chemotherapy and hormone therapy are systemic treatments.

Doctors are always looking for new ways to treat CUP. These new methods are tested in clinical trials. Before beginning treatment, ask your doctor if there are any clinical trials that you might consider.

You may undergo just one treatment or a combination of treatments. Here is a list of main treatments and their goals:

  • Chemotherapy. The goals of chemotherapy are to shrink or slow the growth of the cancer while also reducing the chance that the cancer will spread. This may ease symptoms, prolong life, or even cure the cancer in some cases.

  • Radiation therapy. The goal of radiation is to kill cancer cells by using strong beams of energy. Radiation can be used to kill a cancer in one area of the body or to ease the symptoms of cancer. There are two kinds of radiation--external and internal. For external radiation, a machine delivers radiation from outside of the body. For internal radiation therapy, a doctor places a radioactive source (often in tiny pellets) in or near the cancer to kill the cells.

  • Hormone therapy. This treatment stops the hormones in the body from allowing certain types of cancer cells to grow. Stopping the hormones can be done one of two ways. You may have surgery or radiation to take out or destroy organs that make hormones (such as the ovaries or testicles). Or, your doctor may give drugs that change the way hormones work.

  • Surgery. The goal of surgery is to remove cancerous growths from your body.



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