Cancer of unknown primary

You are here: 

Treatments for poorly differentiated carcinoma of unknown primary

The following are treatment options for poorly differentiated carcinoma of unknown primary (CUP). Your healthcare team will suggest treatments based on your needs and work with you to develop a treatment plan.

When deciding which treatments to offer for poorly differentiated CUP, your healthcare team will consider:


Chemotherapy may be offered for poorly differentiated CUP. Researchers are still looking for the best chemotherapy combinations for this type of cancer.

Extragonadal germ cell tumours

When poorly differentiated CUP is found in adults under the age of 40, doctors usually think that the original tumour was an extragonadal germ cell tumour. This type of tumour starts in the germ cells. Germ cells are usually found in the testicles or ovaries, but extragonadal germ cell tumours start in germ cells that are outside of the testicles or ovaries.

Chemotherapy for testicular cancer may be offered to younger men with a poorly differentiated CUP.

Chemotherapy for ovarian germ cell tumours may be offered to young women with a poorly differentiated CUP.

Other poorly differentiated CUPs

For other types of poorly differentiated CUP found in adults over the age of 40 where it isn’t certain where the primary site is, your healthcare team will offer chemotherapy drugs that they think will work best. This is referred to as empirical chemotherapy. Usually 2 or more drugs will be used. Most combinations include at least one of the following:

  • a platinum drug – either cisplatin or carboplatin (Paraplatin, Paraplatin AQ)
  • a taxane drug – either paclitaxel (Taxol) or docetaxel (Taxotere)

If you can’t have or don’t want cancer treatment

You may want to consider a type of care to make you feel better rather than treat the cancer itself. This may be because the cancer treatments don’t work anymore, they’re not likely to improve your condition or they may cause side effects that are hard to cope with. There may also be other reasons why you can’t have or don’t want cancer treatment.

Talk to your healthcare team. They can help you choose care and treatment for advanced cancer.

Clinical trials

You may be asked if you want to join a clinical trial for cancer of unknown primary. Find out more about clinical trials.

performance status

The measure of how well a person is able to perform ordinary tasks and carry out daily activities.

Examples of scales used to evaluate performance status include the Eastern Cooperative Oncology Group (ECOG), World Health Organization (WHO) and the Karnofsky performance status scale.

germ cell

A reproductive cell (sperm cell in males and egg cell in females).