The medical literature tells us that one of the most stressful times of a patients’ cancer course is the time between discovering that they may have cancer and beginning their treatment. So much is new and unknown. For many patients, this is their first exposure to the health care system. The patient often requires multiple tests and need to consult with different physician specialties, sometimes in different hospitals before treatment can begin.
It can be a time where well meaning family and friends provide advice and anecdotes from their experiences with cancer. Such advice can be helpful but sometimes can lead to further confusion. Add to that the explosion of information on the internet with the gravity of finding out you may have cancer, and it is no wonder that patients find themselves scared, anxious, and confused.
To help organize and simplify the process leading up to the treatment of the patients disease, it may be good to think in terms of a 3 step pathway; diagnosis (what is it?), stage (where is it?), and treatment options (what can I do about it?). Each of these steps is critically important, because the treatment options you will be provided with vary considerably by the type and location of lung cancer and the general health of the patient. If the diagnosis and stage are not adequate, the patient may receive the wrong treatment, and that could adversely effect survival.
DIAGNOSIS (What is it?)
Often lung cancer presents silently, while a patient is having an evaluation for some other reason — for example, a chest x-ray finds a spot when a patient is being admitted to the hospital for gallbladder surgery. Other times a patient presents with symptoms such as a cough that just won’t go away. Either way the doctor, usually a primary care provider, discovers something “not right” on a chest x-ray or CT scan of the chest. They may describe what they find on the x-ray as a lump, spot, shadow, nodule, mass, swelling, tumor, lesion or growth. All of these descriptions are variations on the same theme: there is something in the lung tissue that shouldn’t be there.
If a chest x-ray is where the initial findings were discovered, a CT scan of the chest is almost always the next test to be performed. This test provides valuable information. Computed Tomography (CT or sometimes called CAT scans) supplies the doctor with much more detail than a chest x-ray. The scan is performed with the patient lying on their back, sometimes with an IV to inject the patient with contrast, which allows doctors to distinguish between blood vessels and lung tissue. As the patient is moved through the scanner, pictures are taken at close intervals through the chest and abdomen. One simple way to think about this test is to imagine the chest like a sliced loaf of bread. You can remove a slice of bread at any point in the loaf. Once a CT is performed the doctor can look at three dimensional pictures (slices) at any part of the chest and particularly in the area of interest.
The CT scan will show the size of the tumor, the shape, whether it is pressing or invading something, and sometimes even gives a clue as to whether it is a benign (not cancer) process or malignant (cancerous). It is important to remember that sometimes abnormalities on the scan are not cancer.
The CT can also provide important information about whether the patient has enlarged lymph glands. It is worth pausing here for a moment to describe lymph glands (also referred to as lymph nodes). There is a network of glands throughout the body connected by channels much like, but separate from, our bloodstream. These glands are important, and their main job is help fight infection. Often the doctor tells us that we have swollen glands in the neck, for instance, when we have strep throat. They are an important part of the immune system and filter infectious materials and other cell breakdown products.
Lymph nodes are also vital in patients with lung cancer, because the cancer can spread to the lymph glands. If that occurs, the stage and treatment options the patient may be offered will be different than if there is no lymph gland involvement. Another complementary scan to the CT scan that is being increasingly performed in patients with known or suspected lung cancer called a Positron Emission Tomography (PET) scan. This scan is more of a metabolic scan. It tells us whether what we see on the CT scan is metabolically active. In patients with cancer, the scan should “light up” or show “uptake” in areas where there is tumor.
If the lymph glands are involved, they may also be positive on a PET scan. In addition, disease that has spread outside the chest can be detected with a PET scan. Some hospitals have both (CT and PET) integrated into the same scanner.
Caution must be used when interpreting a PET scan. Occasionally a PET scan can be falsely positive. This means that the scan suggests cancer when the metabolic activity is due to something else, like an infection. In most circumstances, your doctor will want to pursue a biopsy of the area in question, so that you are staged and treated correctly.
Once a CT and/or PET scan is performed and cancer is suspected, the patient is often referred to a pulmonologist (a lung specialist). He or she is likely to oversee the diagnosis, staging, and referral to the most appropriate doctor to treat the cancer.
The first step is usually a biopsy of the tumor. Depending on a number of factors, the approach to the biopsy is either accomplished by performing one of two procedures: a needle biopsy or a bronchoscopy. A needle biopsy is usually performed by an interventional radiologist. The patient is taken to a CT scanner. The skin on the chest or back (depending on the location of the tumor) is numbed using lidocaine (much like when you have work done by the dentist), and a small needle is passed through the chest wall or back into the lung and a biopsy is taken of the tumor. The biopsy is performed under direct visualization by using the CT scan to confirm that the needle is in the tumor while cells are obtained. The procedure is generally safe, though one side effect is worth mentioning: in about 10-15% of patients, as the needle is passing through the chest, lung collapse (partial or total) can occur. Often the patient can just be observed while the lung re-inflates on its own. However, sometimes a tube must be placed in the chest to allow the trapped air out. While this is almost never dangerous, it usually means staying in the hospital overnight.
Another approach to obtaining a biopsy is through a procedure called bronchoscopy. A bronchoscopy is usually performed by a pulmonologist. The test takes place in the hospital but is usually an outpatient procedure. The patient can’t eat or drink for at least 6 hours prior to the bronchoscopy and has to be off blood thinners (including medicines like plavix) for some time before the test. The procedure is performed by providing the patient with IV medication for sedation. The nose and throat are numbed, and a small flexible scope (a bronchoscope) attached by a cable to a TV monitor is gently introduced through the nose or mouth of a sedated patient. The airways are inspected, and biopsies are taken. This procedure also includes a small risk of lung collapse (1-2%) and also possibly bleeding. Patients generally recover in 1-2 hours and are discharged.
A newer technique of bronchoscopy may be offered to which allows doctors to take biopsies of the lymph glands that surround the breathing tubes but can’t be seen directly through the scope. This technique is called endobronchial ultrasound. Simply put, this specialized scope has a miniature ultrasound tip which can look outside the airway at the lymph glands the same way ultrasound is used during pregnancy to look at a baby in the womb. This bronchoscopic technique also allows biopsies of the lymph glands under ultrasound guidance.
Remember, knowing if a lymph node has cancer in it or not alters the stage and treatment options. There are other ways to access the lymph glands, but these require a thoracic (chest) surgeon. Doctors don’t always biopsy the tumor or the lymph glands, but if the imaging is ambiguous and there is a significant chance but not a certainty of lymph node involvement that would change management approach, a biopsy is the way to get a definitive answer.
Sometimes a scan suggests disease outside the chest. If that is the case, the patient may be referred for a biopsy of that particular site (for example, the liver, adrenal gland, bone lesion, etc.).
Staging (Where is it?) and treatment options (what can I do about it?)
Once a diagnosis of lung cancer is confirmed, much effort is made in deciding the correct stage. Often diagnosis and staging occur simultaneously while the patient is undergoing scans and biopsies. Sometimes additional scans are needed, such as a CT scan or MRI of the brain, or a bone scan (though PET scans can detect most bone lesions and have largely replaced them for staging lung cancer in the bones). Once this process is completed, your doctor should be able to establish an accurate stage.
The staging system is standardized from stage 1-4, depending on the extent of disease. Stage 1 and 2 (local disease) are cancers characterized by size and location but generally don’t spread to lymph glands in the center of the chest (the mediastinum). In otherwise fit patients, the treatment is usually removal by surgery alone, or surgery followed by chemotherapy. To better assess the patients ability to tolerate surgery, the doctor may request pulmonary function studies (breathing tests) or a heart stress test.
Stage 3 (locally advanced disease) is characterized by disease has spread to the center of the chest (the mediastinum). The patient should have a lymph gland biopsy to confirm that the tumor has spread to these central lymph glands. The treatment of this stage of disease is generally chemotherapy with radiation therapy. Occasionally, surgery is offered for this stage of disease, but this is uncommon.
Once disease has spread to the opposite lung, the lung lining, or outside the chest, it is considered stage 4 (metastatic) disease, and the treatment is chemotherapy and/or other systemic therapy alone, and when needed a short course of radiation to relieve the symptoms of the cancer.
There are subtle variations in the treatments offered for a given stage. Every case must be evaluated on an individual basis with the different doctors (pulmonologist, radiation therapist, medical oncologist and chest surgeon) conferring to develop the best plan for the patient.
In summary, the diagnosis and staging of lung cancer should be performed in a methodical, stepwise manner, so that the patient can be accurately staged and receive the best available treatment. There are several radiology studies and multiple approaches to obtaining tissue. The sequence of testing depends on many factors taken into account by the multiple physicians when navigating the patient through the process. While there is a strong urgency to move to treatment as quickly as possible, it is even more important to be accurate because that will provide the patient with the most appropriate treatment strategy for their particular cancer.
Finally, please note that I covered much of this subject in a presentation recently, which can be accessed as an audio or video podcast available here.
The GRACE Lung Cancer Reference Library is made possible by an educational grant from Pfizer.