Lung cancer is one of the leading causes of death worldwide. Sometimes it is diagnosed on a routine chest x-ray and other times, a patient is symptomatic and undergoes a more comprehensive evaluation.
Lung Cancer Symptoms
Patients with lung cancer can be asymptomatic and are often surprised when an abnormality is found on a routine chest x-ray. More typically, a patient presents with repeated bouts of pneumonia, coughing up blood, prolonged hoarseness, chest pain, difficulty breathing or other symptoms outside the chest area, which would indicate that cancer is present and has spread beyond the lungs to other organs in the body.
Chest Scan Basics
While a chest x-ray is usually the first diagnostic test performed, a chest CAT or CT (computerized axial tomography) scan is often ordered by the physician as well. The pictures from a CT scan are cross-section images. A chest CT scan not only helps with diagnosing lung cancer but can also be beneficial in tracking the disease through stages. A chest CT scan visualizes the lymph nodes, blood vessels and other vital areas around the lungs and chest area as well as the actual lungs.
The Procedure
A chest CT scan is a noninvasive procedure. It is painless other than the needle stick to start an intravenous contrast dye, if that is ordered. A contrast dye is often injected into the patient’s vein for better visualization. Some patients experience a flushing sensation over their body and a metallic taste in their mouth for about one minute when the contrast dye is injected.
In most cases, the patient lies flat and motionless on a movable examination table, while the CT scanning machine rotates slowly around the patient. The patient will be secured on the table with a strap for safety and pillows for comfort. Sometimes, patients are asked to raise their arms over their head for the scan. The exam table will slide the patient in and out of the machine for the scan. Only the chest area will be imaged in the CT scanner, while other areas are protected with lead aprons or blankets. Patients are asked to hold their breath for several seconds during the scan while specific pictures are taken.
The actual scan takes only about one minute, in most cases, making the entire process take about one half hour. There will be an audible whirring sound while the CT scanner revolves around the patient.
The amount of radiation delivered during the scan can be regulated by the ordering physician and radiologist based on a patient's size. The lowest dose of radiation to obtain the best images is used.
During the scan, the technician conducts the scan from the computer control area in a separate room. The technician has direct visual of the patient during the scan and can communicate through a microphone and speaker system.
The Results
A chest x-ray can detect a tumor in the lung that is about a ½-inch in diameter. A chest CT scan can detect even smaller nodules in the lung. Scans give doctors the ability to diagnose lung cancer in the earliest stages, which allows for a better cure rate.
A trained radiologist will interpret the CT scan images and send the detailed results to the ordering physician. Patients obtain the CT scan results from the ordering physician.
