Cancer of unknown primary (CUP)

Stages and types of cancer of unknown primary (CUP)

The stage of a cancer tells you how big it is and whether it has spread. With CUP doctors can't find where the cancer started (the primary cancer), so there is no staging system.

Stages of cancer of unknown primary (CUP)

There is no staging system for cancer of unknown primary (CUP). Find out why doctors can't accurately stage this cancer type.

Types of cancer of unknown primary (CUP)

CUP can be grouped according to the type of cell they start from. Doctors can find out which type of cell the cancer started in by looking at a sample of the tumour under the microscope.

Last reviewed: 22 May 2024

Next review due: 22 May 2027

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