Lung cancer testing and diagnosis

Lung cancer is one of the deadliest of all cancers and kills more people in one year than breast, prostate and colon cancer combined. This is because by the time symptoms of lung cancer appear, the disease has reached advanced stages which are more difficult and sometimes impossible to cure. In the past, no screening method provided detection of lung cancer in the earliest, more treatable stages so that a sufficient number of the cancers could be cured.

Mammograms, colonoscopy, and pap smears used for early detection of breast, colon, cervical cancers have lead to dramatic decreases in the number of deaths.

Recent studies have shown that earlier detection of lung cancer using low-dose Computerized Tomography (CT) scans reduces death from lung cancer. This painless, non-invasive form of testing has enabled researchers to find much earlier  tumors than would ever be visible through more traditional methods of diagnosis. In fact, patients who were a part of this study who had early diagnosis and sought treatment increased their 10-year survival rate to 80%. Read about lung cancer early detection with CT scans.

There are several methods besides CT scan which can be used to diagnose lung cancer; however, these tests are typically only ordered once symptoms have occurred. The most common methods are:

  • Chest X-ray: Allows the physician to see tumors which are advanced enough or located in areas where they will be visible through pictures taken with a smaller radiation dose than current low-dose CT scans.

  • Sputum Cytology: Mucus coughed up by the patient can be examined under a microscope for abnormal cells.

  • Bronchoscopy: A tube inserted through the nose and into the lungs with a camera at the end allows the physician to look directly into the lungs for signs of tumors. Sometimes a needle is inserted through the tube to extract samples of the tumor or fluid and then examined under a microscope (biopsy). A similar test can also be done using a color video which helps detect light which may be given off by the tissue. This is called "autofluorescence bronchoscopy."

Other tests which might be used include:

  • Magnetic Resonance Imaging (MRI): Use magnetic fields to obtain images of body parts which can show tumors if present.

  • Positron Emission Tomography (PET) Scan: Often used to see if cancer has spread to other parts of the body.

  • Thoracentesis: Needle is inserted to remove fluid which may have collected in the chest area. The fluid is then examined to see if there are cancer cells.

  • Mediastinoscopy: A scope inserted into the chest to see if cancer cells have spread to the area through which the patient breathes (trachea or "windpipe").

  • Thoracoscopy: Surgery used to "explore" lungs and chest area to look for tumors.