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Men and woman discussing unknown primary cancerUnknown primary cancer

All about unknown primary cancer, which means that cancer spread has been found somewhere in your body (secondary cancer), but your doctors can't find out where the cancer started (the primary cancer). Unknown primary cancer is sometimes called Cancer of Unknown Primary or CUP. Information on causes, tests to diagnose cancer, treatment including radiotherapy, chemotherapy, hormone therapy and current research. Living with cancer of unknown primary covers coping with your diagnosis.

More information

You can also find unknown pimary cancer organisations providing help and support, a reading list and see where this information comes from.

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Did you know that Cancer Research UK has an online forum for people affected by cancer? Cancer Chat is your space to talk about cancer.