Non-small cell adenocarcinoma is a type of lung cancer. Lung cancers can be divided into two main groups known as small cell and non-small cell lung cancer, each requiring different treatment. Non-small cell is the most common type, making up more than 80 percent of all lung cancers. The non-small cell group of lung cancers includes adenocarcinoma, squamous cell carcinoma and large cell carcinoma. In the United States, non-small cell adenocarcinoma is the most common lung cancer, while in Europe, squamous cell carcinoma occurs more frequently.
Adenocarcinoma grows from mucus-producing glandular tissue in the airways, or bronchi. In the United States, up to 40 percent of lung cancers are non-small cell adenocarcinomas. It is thought that this may be associated with a greater use of low tar cigarettes.
Around 90 percent of lung cancers are thought to be associated with smoking, and the risk increases with age. Occasionally, adenocarcinomas may arise in someone who has not smoked. Passive smoking and exposure to asbestos, radon gas and some chemicals are all thought to raise the chances of cancerous growths developing in the lungs.
The symptoms of non-small cell adenocarcinoma may not be noticeable in the early stages, and the cancer may be discovered on a routine chest X-ray. When symptoms do occur they may include shortness of breath, coughing which may produce blood, and pain. If the tumor grows into nearby structures, signs such as a hoarse voice and swallowing difficulties may develop. Sometimes no symptoms are experienced until the adenocarcinoma has spread beyond the lungs to organs such as the brain or the skeleton.
Treating non-small cell adenocarcinoma depends on the extent to which the cancer has progressed. In the earliest stages, the entire tumor may be surgically removed and a cure may be possible. Chemotherapy may be given after surgery to destroy any residual cancer cells and to lower the chance of the cancer recurring. In the later stages, when the adenocarcinoma has spread too far to be removed surgically, chemotherapy and radiotherapy may be used, along with other treatments such as biological therapies. Biological therapy drugs attach to special receptors on cancer cells, preventing other substances from locking on which would stimulate the cells to grow.
The general outlook for people with non-small cell adenocarcinoma is poor. Only around 14 percent of people survive for five years after diagnosis. When the disease is discovered and treated at the very earliest stage the prognosis is better, with around 70 percent of people expected to be alive after five years.