If there is reason to suspect that you have lung cancer, your doctor will use one or more of these methods to find out if the disease really exists. If these tests have identified lung cancer, more tests should be performed to clarify to what extent the cancer has spread.
1. Medical history and physical examination
When your doctor takes a “medical history,” he/she will ask you a series of questions about your symptoms and risk factors. While most lung cancers only produce symptoms when they have spread, some of the most common symptoms are due to the cancer growing in the lungs and invading nearby tissues. You should report the following symptoms to your doctor right away.
A cough that does not go away
Chest pain, often worse with deep inhalation
Shoulder pain with numbness in several fingers, with or without droopy eyelids
hoarseness of the voice
Weight loss or loss of appetite
Bloody or rust-colored sputum (saliva or phlegm)
Shortness of breath
Unexplained fever
Recurrent infections such as bronchitis or pneumonia
New asthma attacks
Headache, changes in vision and voice
Seizures
Often these problems are triggered by other factors, but once lung cancer is detected, prompt treatment can prolong life and reduce symptoms. In many cases, lung cancer has spread to other distant organs before it becomes symptomatic itself. Symptoms caused by the spread of lung cancer to other organs include
Bone pain
Weakness or numbness in the hands or feet, dizziness
Yellow coloring of the skin or eyes (jaundice)
Surface lumps caused by cancer spreading to the skin, neck or supraclavicular lymph nodes
Symptom cluster (paraneoplastic syndrome), possibly due to lung cancer
History and physical examination are the first steps in finding out if you have lung cancer and how far it has spread. History and physical examination also provide information about the general condition of the patient. Information other than the lung cancer itself, such as bronchitis, emphysema or heart disease, will help your doctor decide which treatment is right for you.
2. Performance status
Because the side effects of chemotherapy can be severe and have poor tumor shrinkage for patients in poor condition, the patient’s overall health status must be considered to determine whether he/she can receive chemotherapy. This is called the patient’s “performance status.” NCCN physicians use a precise definition of “good” and “poor” condition, based primarily on the Eastern Cooperative Oncology Group (ECOG) performance scale. The ECOG performance scale defines cancer patients on a scale from 0 to 4. A grade of 0 means that the patient is asymptomatic and can do the same work as before the diagnosis of lung cancer. The final level of the scale is 4, which means that the patient is unable to take care of his or her daily activities (such as eating, bathing, dressing, or going to the bathroom) or cannot get out of bed. level 3 means that the patient is able to partially care for himself or herself but needs to spend more than half of his or her waking hours in bed because of discomfort or weakness. In the decision tree of this booklet, “poor general condition” refers to a patient with a level 3 or 4 on the ECOG performance scale.
3. Imaging tests
These tests use X-rays, MRI or radioactive material to produce images of the body to detect the extent of cancer spread.
Computed tomography (CT): Computed tomography, or CT scan, uses X-rays to produce a detailed cross-section of the body. Unlike a regular chest x-ray, a CT scan produces many images as it rotates around you. A computer combines these images to put together an image of a thin slice of your body. The machine will take multiple views of your body for study purposes.
Usually after a series of images are taken, you will be given an intravenous contrast reagent, or color developer, to better help outline the structure of your body. Another set of images is then taken. Some people can get hives from this, and rarely more severe allergic reactions such as difficulty breathing or low blood pressure can occur. Be sure to tell your doctor if you have a previous history of allergies to x-ray contrast reagents (contrast agents).
CT scans will help provide accurate information about the size, shape and location of the tumor and can detect enlarged lymph nodes that may have metastases. CT scans are more sensitive than conventional chest X-rays in detecting early lung cancer.
Magnetic resonance imaging (MRI): MRI scans use radio waves and a strong magnetic field instead of X-rays. The energy of the radio waves is absorbed by the tissue and the particular disease in a specific way and then released. A computer translates the radio waves emitted by the tissue into a detailed cross-sectional image of the body. It can also be used and contrast material is injected intravenously during a CT scan. These images are often used to detect whether lung cancer has spread to the brain or spinal cord.
Radionuclide bone scan: This method will help clarify whether the cancer has spread to the bones. The patient is given an intravenous injection of a radioactive material called technetium diphosphate. The total radioactive energy used is very low and does not cause long-term effects. The radioactive material is absorbed by diseased bone cells in the bones throughout the body. The diseased bone can be seen on bone scans as dense, gray to black areas called “hot spots”. These areas may indicate that the cancer has metastasized, but arthritis, infection, or other bone disease may also cause a similar appearance.
Positron emission computed tomography (PET) scan: This is another type of nuclear medicine study. Small doses of radioactive fluorescent deoxyglucose (FDG) are injected through a vein in the arm. This substance is used by the body like sugar. Because cancer cells consume more sugar than normal cells, more FDG is taken up by the cancer cells and causes more radioactive energy to be emitted, resulting in a brighter image on the scan. This can help identify cancerous tissue from non-cancerous tissue. However, other conditions, such as inflammation, can also show up as brighter images on the scan.
4. Methods and specimens for diagnosing and clarifying the spread of lung cancer
Relying on the results of imaging tests, one or more of the following methods can be used to take samples to clarify whether they contain cancer cells. Pathologists are doctors who specialize in doing laboratory studies to diagnose diseases such as cancer, and they use microscopes to examine samples. If you have questions related to pathology results or diagnostic tests, do not hesitate to ask your doctor. You can get a second opinion on your pathology report, called a pathology review, by sending your tissue specimen to a consulting pathologist at an NCCN center or other laboratory suggested by your doctor
Sputum cytology: examining a sample of sputum (sputum coughed up from your lungs) to see if there are cancer cells.
Fine needle biopsy: Using fluoroscopic fluoroscopy (fluoroscopic fluoroscopy is similar to x-ray, except the image is viewed on a screen instead of on film) to look at both lungs and use a fine needle to guide the mass through the intercostal space. a CT scan can also be used to locate the needle. Once the doctor determines that the needle tip is in the tumor, the sample is removed and sent to the lab. A fine needle can also be used through a bronchoscope to penetrate the wall of the trachea to sample nearby lymph nodes. This method is called transtracheal fine-needle aspiration and is typically used to sample the subserosal lymph nodes (around the trachea where it bifurcates into the right and left bronchi) and mediastinal lymph nodes (along the trachea and major luck duct area).
Bronchoscopy: A lighted, bendable tube called a bronchoscope is passed through the mouth into the bronchi. This test can help find tumors and sample tissue or fluid to see if cancer cells are present. After the diagnosis of lung cancer, the bronchoscope is used to thoroughly examine the inner layers of the other airways of the lung. If other cancers are found that are not close to the original one, it may not be possible to remove all of the cancerous tissue.
Mediastinoscopy: The patient is placed under general anesthesia (under deep sleep) and a hollow, lighted tube is inserted from under the sternum through a small incision at the base of the neck. Special instruments are passed through this tube to be able to take samples from the mediastinal lymph nodes (along the trachea and major bronchial regions).
Thoracentesis: This method is used to determine whether fluid around the lungs is caused by cancer spreading to the pleura (the thin membrane that surrounds the lungs) or by factors unrelated to cancer such as heart failure or infection. A puncture needle is placed between the ribs to drain the fluid, and the cancer cells are looked for under a microscope. If the fluid collects around the lungs, they prevent the lungs from inflating, so thoracentesis can help patients breathe better.
Thoracoscopy: This technique uses a thin tube with a light source attached to a television camera and monitor to look into the space between the lung and the chest wall. This allows the doctor to see tumors on the surface of the lung and to take a biopsy of any suspected areas.
Bone marrow biopsy: A needle is usually used to take a small sample of bone and bone marrow, about 1 inch long and 1/16 inch in diameter, usually from the bone behind the hip. The sample is used to determine if the lung cancer tissue has metastasized to the bone marrow. This is only indicated for certain patients with small cell lung cancer.
Blood tests: Specific hematology tests are often used to determine if lung cancer has metastasized to the liver or bones. These tests include a complete blood count (CBC) and blood biochemistry. a CBC determines whether a patient’s blood contains normal different types of blood cells. Doctors give this test regularly to patients on chemotherapy because these drugs can affect the hematopoietic cells in the bone marrow for a short period of time. Cancer that has metastasized to the liver and bones may produce abnormalities in certain blood biochemical parameters. Doctors perform blood biochemistry tests to detect these abnormalities.