Symptoms of thymus cancer

Thymus cancer may not cause any signs or symptoms in its early stages. Signs and symptoms often appear as the tumour grows and causes changes in the body. In some cases, symptoms can be caused by something associated with a tumour (paraneoplastic syndromes). Other health conditions can cause the same symptoms as thymus cancer.

The signs and symptoms of thymus cancer include:

  • a cough that doesn’t go away
  • chest pain
  • difficulty breathing (also called shortness of breath)
  • a hoarse voice
  • loss of appetite
  • difficulty swallowing
  • Horner syndrome – a rare condition that affects the nerves of the eyes and causes small pupils, a drooping eyelid, sinking of an eyeball into the face and less sweating on the face

Superior vena cava syndrome is a serious problem that can happen in some cases of thymus cancer. It is a cancer-related emergency that needs to be treated right away. Superior vena cava syndrome is a group of symptoms that may happen when a thymus tumour presses on the superior vena cava, which is the large vein that carries blood from the upper body to the heart. Symptoms of superior vena cava syndrome include swelling of the face, neck, arms and chest, difficulty breathing, headache and dizziness. Find out more about superior vena cava syndrome.

Symptoms of paraneoplastic syndromes

A paraneoplastic syndrome is a group of symptoms caused by substances released by a tumour or by an abnormal immune response to a tumour. Paraneoplastic syndromes can disturb the normal function of many different parts of the body. They may be the first sign of a cancerous tumour.

The following are the most common paraneoplastic syndromes associated with thymus cancer.

Myasthenia gravis is a rare autoimmune disease that causes muscle weakness. The body's immune system makes antibodies that block or change some of the nerve signals to your muscles, making them weak. Myasthenia gravis is most commonly associated with thymoma. Symptoms include:

  • weakness in the neck, arms and legs
  • drooping eyelids
  • vision problems, such as blurred or double vision
  • a hoarse voice
  • difficulty speaking
  • difficulty swallowing
  • difficulty breathing

Red cell aplasia is a rare condition where the bone marrow doesn’t make enough red blood cells, which causes anemia. People with red cell aplasia may also have a thymoma. Symptoms include:

  • fatigue and a lack of energy
  • pale skin
  • weakness
  • difficulty breathing
  • dizziness

Hypogammaglobulinemia is a condition when the body doesn’t have enough B cells and causes a low level of gamma globulins in the blood, which normally fight infections. So most people with hypogammaglobulinemia have recurrent infections, often respiratory tract infections. They may also have a thymoma.

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