Lung cancer can cause a number of symptoms, including:
- a nagging cough
- chest, shoulder or back pain, which feels like a constant ache that may or may not be related to coughing
- shortness of breath
- weight loss
- repeated pneumonia or bronchitis
- coughing up blood
- swelling of the neck and face due to the tumor compressing the superior vena cava, the main vein that drains the upper body
Because of the large size of the lungs, cancer may grow for many years, undetected, without causing symptoms. In fact, lung cancer can even spread outside the lungs without causing any symptoms.
It is difficult to diagnose lung cancer at an early stage. Repeated chest x-rays have not been proven to be effective at increasing survival for people with lung cancer. Frequently, people do not have symptoms, or symptoms are vague or they are attributed to other ailments, such as stress, bronchitis, pulled muscles or pneumonia.
Some studies have demonstrated that a new kind of CT scan, called spiral CT, can detect small nodules (early-stage disease) poorly visible on chest x-rays. An advantage of spiral CT is the speed of the test compared to traditional CT. An entire scan can be completed in about 15 seconds. This type of technology, however, is still being tested as a screening test and is not widely available yet. The disadvantage of this testing is it often finds tiny nodules that are not cancerous, yet require additional testing or even major surgery to prove they are benign.