Superior vena cava obstruction (SVCO)

The superior vena cava is a major vein in your body that carries blood from your head, neck, upper chest and arms to your heart. SVCO can occur due to:

• compression of the vein by cancers or nearby swollen lymph nodes
• blood clots in the vein
• cancers spreading from other parts of your body to the vein.

The most common cause of SVCO is lung cancer. It can either compress directly on the superior vena cava or spread to nearby lymph nodes, causing them to swell and press on the vein. Other types of cancers that can spread to nearby lymph nodes include:

• lymphoma
• breast cancer
• bowel cancer
• oesophageal cancer
• testicular cancer.

SVCO can also occur if there are blood clots forming in the superior vena cava, blocking the blood flow. This can occur as a side effect of cancer itself, or after a small tube (central line) is inserted into the vein to give medications such as chemotherapy. 

Symptoms can develop quickly over a few days or gradually as a long-term problem. Common symptoms of SVCO include:

• breathlessness
• changes in vision
• dizziness
• headache that worsens when bending forward or lying down 
• cough
• chest pain
• visible blue veins on your chest or neck
• face, neck or arms swelling
• difficulty swallowing.

Your doctor will take a history and do a physical examination and request some tests based on your symptoms. This usually involves urgent scanning of your chest such as a chest X-ray, MRI or CT scan.

Your doctor will discuss with you the best treatment options beforehand, depending on the type of cancer you have. Before treatment is started, your doctor may ask you about your wishes or whether you have any advance care plan. You may also be admitted to hospital to receive treatment and be referred to a palliative care specialist.

Treatment aims to reduce compression of superior vena cava and relieve symptoms. Your doctor will consider giving you the following medications:

• oxygen
• pain relief medication
• water tablets to remove extra fluid 
• steroids such as dexamethasone, prednisone or hydrocortisone to help reduce swelling and pressure on the vein, if the cancer is responsive to steroids
• sedating medications such as benzodiazepines or opioids to help you relax
• drugs for blood clots or anticoagulants.

Sometimes, you may need a procedure called stenting to relieve the obstruction. The procedure involves putting in a small tube in your vein to keep the blood flowing. It is usually done with local anesthetic. You may also need radiotherapy or radiation treatment to destroy cancer cells around the area of compression. 

It can be scary to have SVCO as the condition can cause difficulty breathing. Talk through your feelings with your family members or health professionals taking care of you.

Below are some support services and information for people affected by cancer and their family/whānau:

Emotions and cancer(external link) Cancer Society of NZ
How we can help(external link) Cancer Society of NZ
NZ cancer services – find a hospital/service near you(external link) Healthpoint, NZ
More cancer support groups