Treating unknown primary cancer

Thursday 1 May, 2014

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On this page: ChemotherapyRadiotherapySurgery | Hormone treatmentPalliative care | Key points

When tests have been unable to find the primary cancer, a diagnosis of CUP is given. This is often a difficult time and it can be hard to accept that the primary cannot be found. Some people may feel relieved that the tests are over and that treatment options can be considered.

To work out what treatment to suggest your doctors will use the information they have about the cancer, including:

  • the location of the secondary cancer
  • test results
  • how likely it is to be a certain type of cancer.

CUP can be treated using chemotherapy, radiotherapy, surgery and hormone treatment or a combination of these. Suitability for treatment will depend on factors that are unique to your situation, and will usually be assessed by the multidisciplinary team.

For many people, CUP is diagnosed at an advanced stage and treatment is unlikely to cure it. However, treatment may be able to control the cancer and improve your symptoms. It is possible that treatment may make you feel better and help you live longer. This is called palliative care

"I found it complex to talk to people about my cancer. I can explain it, but they find it hard to understand. It does seem incomprehensible to have a cancer that has spread but no named starting point." – Jane


Chemotherapy is the treatment of cancer with anti-cancer (cytotoxic) drugs. The aim of chemotherapy is to kill cancer cells while doing the least possible damage to healthy cells.

Chemotherapy is used to shrink tumours, and to relieve symptoms caused by the cancer. It can also be used in combination with radiotherapy or surgery to try and kill any local collections of cancer cells in the body. Different cancer cells respond to different chemotherapy drugs. People with CUP may have a combination of drugs.

Generally, chemotherapy is given intravenously through a drip or plastic tube (catheter) inserted into a vein in your arm, hand or chest. The drugs circulate through the bloodstream and can kill cancer cells throughout the body (called systemic treatment). Some types of chemotherapy are taken orally (tablet form).

Chemotherapy is given in cycles, which consists of a treatment period followed by a recovery period. The number of treatment cycles you have depends on your situation. You may be able to have treatment as an outpatient but sometimes a short stay in hospital is required. 

Let your doctor know if you are taking nutritional or herbal supplements as these can interact with chemotherapy drugs and may be harmful.

Side effects
  • Most chemotherapy drugs cause side effects. Different drugs have different side effects. Your medical oncologist or nurse will discuss them with you.
  • The most common side effects include feeling sick (nausea), vomiting, mouth sores, tiredness, loss of appetite, diarrhoea and some thinning or loss of hair from your body and head. Most side effects are temporary, and can be prevented or reduced. Many go away when treatment ends.
  • Chemotherapy weakens the immune system making it harder for your body to fight infections. You will have regular blood tests to check your immune system. If your temperature is 38°C or above while receiving chemotherapy, contact your medical oncology team or hospital immediately.
For more information call Cancer Council 13 11 20 or see our chemotherapy section.


Radiotherapy uses x-ray beams to kill cancer cells. Some people with localised squamous cell carcinoma in the neck lymph nodes may have high dose chemoradiation to try and cure the disease.

Radiotherapy can also be used to relieve symptoms such as bleeding, difficulty swallowing, breathlessness, blocking of the intestines, compression of blood vessels or nerves by tumours, and pain caused by cancer spreading to the bones.

To plan radiotherapy treatment, your doctor will take an x-ray of the treatment area. To ensure that the same area is treated each time, the radiation therapist will make a few small marks on your skin. Sometimes these are permanent tattoos.

You may have treatment as external or internal radiotherapy. External radiotherapy is given from a machine outside the body, and for internal radiotherapy a radiation source is put inside the body on or near the cancer. Radiotherapy treatment is painless. The total number of radiotherapy treatments and their duration will depend on your situation. Sometimes only a couple of treatments are necessary, or you may need radiotherapy every weekday for several weeks.

Side effects
  • The side effects of radiotherapy depend on the area of the body being treated and the dose of radiation.
  • Common side effects include nausea, loss of appetite, diarrhoea, tiredness and shortness of breath. It can also make your skin dry and itchy in the treatment area. Your skin may look red or sunburnt.
  • Side effects tend to develop as you go through treatment and most improve or go away after treatment is finished.
  • Talk to your doctor or nurse about ways to manage the side effects of radiotherapy.
For more information call Cancer Council 13 11 20 or see our chemotherapy section.


Surgery is a common treatment for many types of cancer if they are found at an early stage. With CUP, the cancer has already spread beyond the site where it started, so surgery may not be used as a treatment.

If the cancer is found in only one area (e.g. in the lymph nodes in the neck, underarm or groin) it may be possible to remove it with an operation. Small secondary cancers in the brain are sometimes removed in people who are well enough to have surgery and who don't have any other secondary cancers. If the cancer has spread extensively, it may not be possible to remove it all surgically.

Surgery may be followed by radiotherapy or chemotherapy to kill any cancer cells left in the body. Sometimes surgery is recommended to help with symptoms. For example, surgery may help relieve the discomfort or pain caused by a cancer pressing on a nerve or organ.

Side effects
  • Some people experience pain after surgery but this is often temporary.
  • Talk to your doctor or nurse about pain-killers.
  • If you’ve had lymph nodes removed, you may develop lymphoedema. This is swelling caused by a buildup of fluid in part of the body, usually in an arm or leg.
  • For more information see the Lymphoedema Association of Australia website.

For more information call Cancer Council 13 11 20 or see our chemotherapy section.

Hormone treatment

Hormones are substances that occur naturally in the body, but they can also be man made (synthetic). These synthetic hormones are used to block the effect of the hormones in the body that help cancer cells grow. Hormone treatments may be taken as tablets by mouth or given as injections.

Hormones may be used to treat hormone-dependent cancers, such as breast, prostate or uterus, where the cancer cells are stimulated to grow by oestrogen (breast cancer) or testosterone (prostate cancer).

Hormone treatments are also sometimes used for kidney cancer and for melanoma. If CUP is thought to have originated in one of these organs, hormone therapy may be recommended to slow the growth of the cancer or shrink it.

Hormone treatment may be used in combination with other treatments, e.g. to shrink a tumour before radiotherapy or surgery.

Side effects
  • General side effects include tiredness, nausea, diarrhoea, constipation, appetite changes, weight gain, mood changes, pains in your joints and thinning of your bones.
  • The side effects vary depending on the hormones you are given.
  • Women may experience menopausal symptoms such as hot flushes, which may be temporary or permanent.
  • Men may have problems getting an erection (impotence).

Palliative care

Palliative care helps to improve people’s quality of life by alleviating symptoms of cancer. It brings together different services and health professionals who work together as a team. It can include medical treatment, nursing care, social work, occupational therapy, physiotherapy, counselling and dietary assistance. You may have chemotherapy, radiotherapy or hormone therapy as palliative treatments.

Often palliative care is concerned with pain relief, but it can also help manage other physical and emotional symptoms, such as depression. Palliative care:

  • can be provided at home, a hospital or a palliative care unit
  • is available at different stages of cancer
  • regards dying as a natural event and does not prolong cancer treatment when it is no longer beneficial
  • does not include deliberate ending of life (euthanasia)
  • offers support for families and friends during a person’s illness and in bereavement.

It is best to make contact with a palliative care team as early as possible. You can find out what the different team members do to determine which services might be useful now or in the future. This will vary according to how you feel, what problems you have and how your carers are managing. Talk to the team about your needs and how they can help.

Call Cancer Council 13 11 20 to request free information about palliative care and advanced cancer.

Linda's story

"My husband Steve was diagnosed with cancer of unknown primary. It started off with a sore back. Then he had trouble walking and the pain was unbearable.

"Steve had some scans, which showed a mass. He was then referred to the hospital for further tests and an MRI.

"They never found the primary site; they only found the secondary sites on my husband’s spine, in his lungs and in his liver. The doctors said the cancer was inoperable and untreatable.

"He had chemotherapy and radiation to relieve his pain and to reduce the size of the secondary tumour on his spine.

"I nursed Steve at home but took him to hospital for chemo. I gave him injections to help control his pain. We also had an excellent palliative care nurse visit every day."

Tell your cancer story.

Key points

  • Treatment can help control the symptoms of CUP but it may not cure the disease.
  • There are many types of treatment for CUP, including chemotherapy, radiotherapy, surgery and hormone treatment. Your treatment will depend on the type of cancer cell, the suspected primary site and the location of the secondary cancer(s). It will also depend on your general health.
  • Chemotherapy treats cancer with drugs. Most chemotherapy drugs cause side effects, such as nausea, vomiting, fatigue, hair loss, mouth sores, loss of appetite, diarrhoea, and increased risk of infections. Side effects depend on what kinds of drugs you are given.
  • Radiotherapy treats cancer by using x-ray beams to kill cancer cells. It is painless but radiotherapy may cause side effects such as burning on the skin, scarring or shortness of breath. Other side effects include tiredness and nausea.
  • Surgery may be used to remove lymph nodes in the neck, underarm or groin. It’s not always a treatment option for CUP, and sometimes only some part of the cancer can be removed.
  • Hormone treatments are sometimes used to treat CUP by slowing the growth of the cancer or shrinking it.
  • Palliative care is treatment that helps improve quality of life. If possible, get in touch with the palliative care team early.

Reviewed by: A/Prof Linda Mileshkin, Consultant Medical Oncologist, Division of Cancer Medicine, Peter MacCallum Cancer Centre, VIC; Karen Hall, Nurse Counsellor, Helpline, Cancer Council SA and Clinical Nurse, Oncology/Haematology Inpatient Unit, Flinders Medical Centre, SA; A/Prof Chris Karapetis, Director of Clinical Research, Medical Oncologist, Flinders Centre for Innovation in Cancer, SA; A/Prof Claire Vajdic, Team Leader, Cancer Aetiology and Prevention Group, Prince of Wales Clinical School, Lowy Cancer Research Centre, University of NSW, NSW; and Robyn Wagner, Consumer.

Updated: 01 May, 2014