Symptoms and Complications
The first and most common symptom of lung cancer is a cough. If someone
with chronic bronchitis develops lung cancer, the cough due to bronchitis will
get worse. Cancer may grow into the blood vessels and cause blood to be coughed
up in the phlegm. It may also grow into or press on the bronchi, making them
narrower and causing the patient to wheeze when trying to breathe. Cancer can
grow into the chest wall, causing chest pain. It can also cause pneumonia, with
its symptoms of cough, fever, chest pain, and shortness of breath. People with
advanced lung cancers lose their appetite, feel weak, and lose weight.
Lung cancer can spread to parts of the body near the lungs or to other parts
of the body such as the liver, brain, and bones, causing pain. Cancer spreading
within the lung can reduce the amount of oxygen available in the blood, resulting
in heart failure. It can also grow into and block the veins that go from the
upper part of the body to the heart. This syndrome, called superior vena
cava syndrome, causes the blood in the veins of the face, neck, and upper
chest to back up and the veins to swell.
Cancer can cause fluid to fill the sacs surrounding the heart or lung, making
it very hard to breathe. Cancerous cells can also press on the lung, causing
it to collapse, or on the spinal cord (backbone), causing pain or the loss of
function of the nerves. Some cancers also release hormones that can affect the
body's metabolism.