Lung Cancer: Diagnosis

The evaluation of lung nodules and diagnosis of lung cancer often includes:

• A complete history and physical exam
• A chest X-ray
• A chest CT scan (a specialized X-ray which produces detailed pictures of the lungs)
• Other imaging studies. Imaging studies may be needed to determine the lung cancer stage.
• Breathing tests, called pulmonary function tests. These detect emphysema and asthma as well as their impact on airflow out of the lungs.
• A biopsy of the lung nodule. A biopsy of the lung nodule is important to obtain a sample of the lung nodule to view under a microscope. A pathologist can determine if the cells are normal, abnormal or cancer cells.

Biopsy of the Lung Nodule

If a lung nodule is considered highly suspicious based on its size, shape and appearance on a chest X-ray or CT scan, as well as any risk factors you may have for lung cancer (age, smoking history, etc.), it will need to be biopsied to determine if it is cancerous. The biopsy is a simple procedure of getting a sample from the lung nodule to view under a microscope. A biopsy of the lung nodule can be done by bronchoscopy, by placing a needle through the chest wall and into the nodule under radiographic guidance or through a small operation.

• Bronchoscopy: Getting a biopsy using bronchoscopy is done as an outpatient procedure without any cutting, sutures or needles. During a bronchoscope you will be sedated and your mouth and throat will be numbed. A small tube (bronchoscope) with an even smaller video camera on the end will be placed through the nose and into the lungs. The bronchoscope will be guided to the lung nodule by the doctor operating the instrument based on the location in the chest X-ray or CT and, often, using a computer-assisted guidance system. A biopsy of the lung nodule is taken and examined twice by a pathologist (a doctor who identifies diseases by studying cells and tissue under a microscope). The biopsy is immediately examined to determine if the nodule is cancerous and is again examined by the pathologist over 48 hours using special techniques to be certain of the diagnosis.
• CT Guided Fine Needle Biopsy: Getting a biopsy using a fine needle biopsy is also done as an outpatient procedure. During a fine needle biopsy you will be sedated. A fine needle will be inserted into the skin, which is numbed. The doctor guides the needle to the lung nodule by observing repeated CT scans during the procedure. The needle is guided into the lung nodule, and then the biopsy is taken. The biopsy is examined as described above.
• VATS Procedure: A biopsy may need to be taken from the lymph nodes that are in the area between the lungs (mediastinum). This procedure is a small operation and you will be sedated deeply. During a mediastinoscopy a small incision will be made above the sternum. A small tube with an even smaller video camera on the end will be placed through the incision. This will be guided to the lymph nodes by the doctor operating the instrument based on the location on the chest X-ray or CT. During a mediastinotomy a different approach to get a lymph node biopsy is taken through a larger incision between the ribs, and then the tube is inserted.
  
  Occasionally a surgical biopsy of the lung and lung nodule must be performed. This is typically done using Video Assisted Thoracoscopic Surgery (VATS). This is an operation and will be performed in an operating room. A small incision is made between the ribs, the lung is deflated and a small camera is inserted into the chest cavity. When the area or nodule to be biopsied is identified, small surgical instruments are inserted through two to three other small incisions (less than an inch) between the ribs and the nodule is biopsied or removed. The instruments are removed, the lung is reinflated and any incisions are sutured shut.

If you do not receive a diagnosis of lung cancer, or the lung nodules are not cancerous, your doctor will ask you to come back to re-examine the spot so he/she can watch it for any changes and be certain it is not cancerous. If the lung nodule is cancerous, a few more studies will be performed to determine if the cancer has spread. This may include specialized radiographic scans of your body and brain and potentially biopsies of other areas.

If you receive a diagnosis of lung cancer, you will be referred to a cancer specialist, called an oncologist. The oncologist will recommend a combination of treatment based on your stage of cancer and the sub-type of cancer you have.

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