Cancer of unknown primary


Managing symptoms

Page last updated: October 2024

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Symptoms and side effects vary from person to person – you may have none or only a few. This section describes the most common symptoms and side effects experienced during treatment for CUP.

You may experience others not mentioned here. Talk to your treatment team about ways to manage any symptoms and side effects you have.

Your guide to best cancer care

A lot can happen in a hurry when you’re diagnosed with cancer. The guide to best cancer care for liver cancer can help you make sense of what should happen.

It will help you with what questions to ask your health professionals to make sure you receive the best care at every step.

Read the guide

Pain

Many people with cancer worry that they will be in pain. Not everyone will have pain, and those who do may find it comes and goes. Pain is affected by the location of the cancer and its size.

Ways to relieve pain include:

  • pain medicines, such as paracetamol, ibuprofen and other non-steroidal anti-inflammatory drugs, and opioids (e.g. oxycodone, morphine)
  • medicines that are normally used for other conditions, such as antidepressants and anticonvulsants (known as adjuvant analgesics)
  • procedures to block pain signals (e.g. nerve blocks or spinal injections)
  • therapies, such as massage, meditation, relaxation, hypnotherapy, exercise and physical therapy
  • psychological therapies that can change the way you think about and respond to pain
  • cancer treatments used palliatively.

Often a combination of methods is needed and it may take time to find the right pain relief. If one method doesn’t work, you can try something else. Be sure to tell your doctor and pharmacist of all medicines you take.

“During the treatment, I had pins and needles in my hands and in my feet. Walking just got to be almost impossible because I couldn’t quite walk properly at all.” Phil

Using cancer treatments to control pain

Fatigue

For many people, feeling tired and lacking energy can be the most difficult symptom to manage. It can be very frustrating if other people don’t understand how you’re feeling.

Fatigue can be caused by a range of things, such as:

  • the cancer itself or cancer treatments
  • low levels of red blood cells (anaemia) or high levels of calcium in the blood (hypercalcaemia)
  • drugs such as pain medicines, antidepressants and sedatives 
  • infection
  • loss of weight and muscle tone
  • anxiety or depression
  • lack of sleep
  • poorly managed pain.

Tips for managing fatigue

Learn more

Nausea

Feeling sick in the stomach (nauseated) is an unpleasant symptom that may be caused by the cancer itself. Nausea can also be a side effect of some types of chemotherapy, but anti-nausea medicines can often prevent or manage this.

Other causes of nausea include:

  • treatment with radiation therapy
  • stress or anxiety
  • too much or too little of a mineral in the blood (e.g. calcium) 
  • drugs used to control other symptoms (e.g. morphine for pain)
  • the kidneys not working properly
  • a bowel blockage (obstruction) or constipation
  • increased pressure around the brain as a result of cancer in the brain or cancer affecting the flow of fluid around the brain and spinal cord.

Tips for easing nausea

Loss of appetite

Not feeling like eating is a common problem faced by people with CUP. This may be caused by the cancer itself or side effects of treatment. You may not enjoy the way food tastes or smells, or you may be worried about the diagnosis and treatment.

You might also not want to eat much if you are feeling sick (nauseated) or have a sore mouth or oral thrush infection. These problems can often be managed, so let your treatment team know.

You may go through periods of having no appetite. These may last a few days or weeks, or be ongoing. During these periods, it may help to have liquid meal substitutes. These are high-kilojoule drinks containing some of the major nutrients needed by your body. Drinking these may help keep your energy levels up during periods when your appetite is poor.

Tips for when you don't feel like eating

Nutrition and Cancer

Breathlessness

Some people with CUP experience shortness of breath. Causes include: 

  • fluid surrounding the lungs (pleural effusion)
  • an infection in the lungs
  • a blood clot in the lungs (pulmonary embolism)
  • pressure from the cancer itself or from a swollen abdomen
  • anaemia (low levels of red blood cells).

Treatment will depend on the cause. You may need fluid drained from the chest (pleural tap) or medicine for an infection or other lung problem. A low-dose opioid medicine is sometimes prescribed.

Feeling short of breath may make you feel anxious, which can make the breathlessness worse. Your doctor or a psychologist can help you find ways to manage any anxiety.

Tips to help your breathing

Get support

Many people feel shocked and upset when told they have cancer. It can be even more distressing if the cancer has spread and the original (primary) site cannot be found.

Cancer Council's experienced nurses can help you connect with other people who are living with advanced cancer, and provide you with information about the emotional and practical aspects of living with CUP.

Contact cancer support

Understanding Cancer of Unknown Primary

Download our Understanding Cancer of Unknown Primary booklet to learn more and find support.

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