Cancer of Unknown Primary (CUP)

This diagnosis is made when a tumor is found and its location and appearance suggest that it started somewhere else in the body, but the original location is never found.

The National Cancer Institute estimates that 2 percent to 4 percent have CUP – as many as 56,000 Americans this year will be diagnosed with CUP.

CUP is slightly more common among men than women, and the average age of patients is about 60.
Overall, this is a very dangerous cancer. Only about half of patients will live 9-12 months after diagnosis.

There are several reasons why CUP is so serious:

• Most are fast spreading.
• Because the exact type of cancer is not known, it more difficult for doctors to know what treatment is likely to help.
• Because the cancer is usually widespread, it is rarely curable.

What does the future hold for CUP?

Because CUP is not one specific type of cancer but rather a diverse group of many types of cancers, the greatest progress against CUP is likely to depend on continued advances in the understanding of the molecular basis of all cancers. Scientists at Vanderbilt-Ingram and other leading cancer centers are learning more every day about how changes in a person’s DNA can cause normal cells to develop into cancer. A greater understanding of the genes (regions of a person’s DNA) involved in these abnormalities is shedding into how and why this transformation occurs.
Someday, doctors may be able to take a sample of CUP, analyze its patterns of genetic expression and compare those patterns against the patterns of known cancers to help determine its
origin.

For more information about cancer of unknown primary and doctors at Vanderbilt-Ingram Cancer Center who treat CUP, log on to www.vicc.org, click on cancer types and go to carcinoma of unknown primary. Or call our Cancer Information Program at (800) 811-8480.