There are two major forms of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer. They're diagnosed based on differences in cancer cell structure under a microscope. Here are key facts about non-small cell lung cancer, the most common.
Vast majority of lung cancer cases are non-small cell
Non-small cell lung cancer occurs when malignant cells form in the tissues of the lung. This type accounts for about 80 percent of all lung cancer cases.
Types of non-small cell lung cancer
There are three different types of non-small cell lung cancer. They are:
Squamous cell (epidermoid) carcinoma: Accounts for about one-third of NSCLC cases and usually occurs in smokers.
Adenocarcinoma: Accounts for about 35 percent of NSCLC cases and can occur in both smokers and non-smokers.
Large cell carcinoma: This is a very aggressive form of NSCLC that grows and spreads rapidly. It accounts for less than 10 percent of NSCLC cases.
Most patients with early stage lung cancer are asymptomatic
This means they do not exhibit clinical signs or symptoms of the disease. The absence of clinical signs and symptoms during the early stage of the disease is a major factor that often contributes to a significant delay in diagnosis of the condition.
There are numerous symptoms of lung cancer, but the most common ones are persistent or worsening cough, shortness of breath (dyspnea), and coughing up blood or rust-colored sputum.
In general, some of the more common problems encountered by cancer patients either as a result of the disease itself or as a side-effect of cancer treatments include:
Diminished exercise capacity
Unintentonal weight loss
Smoking greatly increases a person's risk
The earlier you begin smoking and the longer you smoke, the greater your risk of developing lung cancer. Other risk factors include family history, secondhand smoke exposure, and air pollution.
Survival rate varies by stage
According to data from the National Cancer Institute, the average five-year survival rate for someone with stage IV non-small cell lung cancer is 1 percent. By contrast, the average five-year survival rate for someone with stage 1A non-small cell lung cancer is 49 percent.
New testing for early detection underway
Research has shown that doing spiral CT scans and testing sputum samples in people who are at higher risk for lung cancer may be effective in early detection.