What to Know About Radiation Therapy for Carcinoma of Unknown Primary Origin

Radiation is often used to relieve the symptoms of carcinoma of unknown primary origin (CUP). Sometimes radiation may also be used to cure the cancer if it has not spread too far.

Doctors give radiation for CUP in two ways – externally or internally. The type of radiation therapy you receive depends on the location, size, and spread of the cancer.

External radiation is the most common radiation treatment for CUP. You get it from a machine outside your body. You will have treatments 4 to 5 days a week for several weeks in a row.

Internal radiation is less frequently used to treat CUP. For internal radiation, you will have an implant of radiation placed in or near the tumor.

Potential side effects

Radiation affects both normal cells and cancer cells. This means it can cause side effects. What they are depends on what part of your body is treated. Common side effects of radiation include fatigue and skin changes. These are common side effects of radiation:

  • Diarrhea

  • Fatigue

  • Nausea

  • Skin irritation

Usually these side effects go away after treatment. Many can be helped with certain medications.