Lung Cancer Diagnosis
Early-stage lung cancer often does not have symptoms. In addition, when symptoms appear they can easily be mistaken for common respiratory illnesses like bronchitis or pneumonia. Because of this, many cases are diagnosed at an advanced stage.
Patients at high risk for lung cancer, especially those with a history of smoking, should undergo regular screenings in order to catch the disease at its early stages, when there is a better chance of cure.
If you have symptoms that signal lung cancer, your doctor will ask you questions about your medical, smoking and family history and whether you have been around certain chemicals or substances.
The following tests may be used to diagnose lung cancer or monitor how the patient responds to treatment.
Lung cancer imaging exams
Imaging exams look for cancer inside the body. They can help locate tumors and track how the body is responding to treatment. There are many types of imaging exams. The ones used for lung cancer include:
- Chest X-ray: X-rays use low doses of high-energy radiation that travel through the body to create an image. X-rays are used to image bone and can also help spot possible tumors. Chest X-rays are typically the first imaging exam used to help diagnose lung cancer.
- CT scan: A CT scan uses an X-ray machine to take several pictures from different angles. These are combined to create a highly detailed image that can confirm the presence of a tumor.
- PET scan: During a positron emission tomography scan, or PET scan, a small dose of radiolabeled sugar is injected into a patient. A scanner shows where the body distributes the sugar, allowing for the creation of an image. Cancer cells consume more of this sugar than healthy cells, so this image can help doctors find cancer throughout the body. This is a routine test for determining the cancer’s stage.
- MRI scan: Magnetic Resonance Imaging, or MRI, uses magnetic fields and radio waves to generate pictures of the body’s soft tissue and organs. Doctors use MRIs to look for the spread of lung cancer to the brain.
Learn more about imaging exams.
Lung cancer biopsy
If the findings on the imaging exams indicate cancer, the doctor will request a biopsy.
A biopsy is the only way to definitively diagnose lung cancer. During a biopsy, a small tissue or fluid sample is removed and examined under a microscope for the presence of cancer cells. Depending on tumor location, some biopsies can be done on an outpatient basis with only local anesthesia. Other times, patients must undergo a surgical biopsy under general anesthesia.
There are several ways doctors can perform biopsies of lung tumors:
- Needle biopsy: A CT-guided biopsy where a needle is inserted through the skin under local anesthesia to acquire a tumor sample. This is one of the most common biopsy procedures for lung cancer.
- Bronchoscopy: This is the standard biopsy procedure for lung cancer. A thin, flexible tube with a tiny camera is inserted through the nose or mouth and down into the lungs to obtain a small tissue sample (biopsy). This is usually performed under mild sedation. Bronchoscopies are usually performed with an endobronchial ultrasound.
- Thoracentesis: Fluid from around the lungs is drawn out with a needle and tested for cancer cells. Thoracentesis is used when imaging exams indicate the cancer may have spread to the pleura, the membrane that surrounds the lungs and chest wall. Thoracentesis is usually performed in combination with other biopsy methods.
- Endobronchial ultrasound (EBUS): A bronchoscope with an attached ultrasound device is used to check for lung cancer inside nearby chest lymph nodes. EBUS is often performed at the same time as a bronchoscopy and requires general anesthesia.
- Video-assisted thoracoscopic surgery (VATS): This minimally invasive surgical procedure uses a small camera to help retrieve tumor samples that are otherwise difficult to access. VATS requires a general anesthetic and is performed in the operating room by a thoracic surgeon. VATS is used only in limited situations.
- Thorascopy/pleuroscopy: A tiny camera is inserted through a small incision in the back (for a thorascopy) or between the ribs (for a pleuroscopy). Doctors use this device to look for and retrieve suspected cancer tissue. This procedure is used only in limited situations.
Molecular diagnosis
Different cancers have different features on the molecular level. A molecular diagnosis identifies the features that impact how the cancer responds to specific therapies. Doctors use this information to develop the most effective treatment plan for each patient.
Blood tests
Advanced blood tests, known as circulating tumor DNA (ctDNA) tests, can look for fragments of cancer cell DNA in the blood. Currently, ctDNA tests are used to help identify the cancer’s subtype.
Standard blood tests can also help monitor the cancer and how the patient is responding to treatment.
Bronchoscopy 101: How it helps diagnose and treat lung conditions
A bronchoscopy is a minimally invasive medical procedure in which doctors use a special scope to examine the inside of your lungs and airways. It is used frequently to diagnose and stage lung cancer.??
But can a bronchoscopy tell us anything else? Do you have to be put to sleep to have one? And how long does it take to recover??
Read on, for answers to these questions and more.?
What are the different types of bronchoscopy?
Diagnostic bronchoscopy
We use robotic bronchoscopy to biopsy lung nodules and a technique called endobronchial ultrasound (EBUS) to sample lymph nodes for cancer staging.??
We also use a technique called bronchoalveolar lavage (BAL), typically in immunocompromised patients, to diagnose opportunistic infections of the lungs. To do a bronchoalveolar lavage, we wedge the bronchoscope in the section of the lung we’re interested in, flush it with a saline solution, extract the fluid, and culture it in a lab to see what grows.??
Therapeutic bronchoscopy
Mostly performed via rigid bronchoscopy, this procedure is used to remove tumors that are blocking the windpipe, to cauterize bleeding tumors, or to place stents that keep the windpipe open. It won’t cure cancer, but it should make breathing easier.?
How long does a bronchoscopy take??
That depends. The shortest procedure is the bronchoalveolar lavage, which can take just 10 to 20 minutes. The diagnostic bronchoscopy of a lung nodule can take 45 minutes to an hour, and the sampling of lymph nodes for staging can add another 45 minutes.??
But if we’re doing it strictly for therapeutic purposes, it can take from one to two hours, depending on the complexity of the case.?
Keep in mind, though, that these are all estimates. The length of each procedure is determined by the number of lung nodules or lymph nodes being biopsied, and doctors don’t know this until they are looking inside your lungs.?
Are you awake during a bronchoscopy?
Not necessarily. You’ll be given general anesthesia in most cases, but moderate sedation if you only need bronchoalveolar lavage.?
Is a bronchoscopy considered a serious procedure??
That depends on how you define it. I consider anything requiring general anesthesia to be a serious procedure.??
But doctors will be working inside your lungs, which are the most vital organs aside from the heart. So, it is more serious than a colonoscopy, for example, but less serious than most surgeries.??
Is a bronchoscopy considered a high-risk procedure??
Bronchoscopy for the diagnosis of lung nodules, sampling of lymph nodes, or bronchoalveolar lavage is commonly considered a moderate-risk procedure. On the other hand, therapeutic bronchoscopy is always considered high-risk because patients are sicker to begin with. They often have collapsed or obstructed airways, low oxygen levels, or they are actively bleeding.??
What are the risks of a bronchoscopy??
With diagnostic and staging bronchoscopies, the risks are mainly from the anesthesia, rather than the procedure itself. General anesthesia can lower your blood pressure, which can be risky if you have underlying cardiovascular disease. It can also weaken the breathing muscles, so you tend to take shallower breaths when you wake up from anesthesia, and that can make your blood oxygen levels drop.??
Biopsies of the lung nodules or lymph nodes have minimal risk of bleeding and infection, but biopsy of lung nodules can sometimes lead to lung collapse (pneumothorax). That’s why even if everything goes well, we prefer our patients to avoid long-distance traveling or air travel until the next day.??
With therapeutic bronchoscopies, the risks are higher, and they generally involve bleeding, having low oxygen levels, and difficulty breathing. But all of these are dependent on each patient’s particular situation, and your doctor will go over which ones apply to you in detail.??
How long does it take to recover from a bronchoscopy?
Most diagnostic and staging bronchoscopies are outpatient procedures. Patients remain in the recovery area for 45 minutes to an hour afterward, and then they go home. They generally feel tired on the day of their bronchoscopy, but they are back to their baseline the following day.??
The recovery time is similar for therapeutic bronchoscopy patients, even if they are already admitted to the hospital.??
Is a bronchoscopy painful?
No. The lungs have no pain receptors, so they do not hurt, and you are also sedated. You should not experience chest pain after bronchoscopy, either, unless you are coughing really hard.?
Does a bronchoscopy have any side effects?
Some patients report having a sore throat due to the breathing tube. And patients can expect to cough up mucus tinged with blood for the next 2 or 3 days. But those are both normal and will resolve on their own.?
Is a bronchoscopy better than a CT scan??
These two tests play very different roles. A CT scan is the test that generally finds out there is something wrong in your lungs. But it can only tell you that there’s an abnormality present. It cannot tell you exactly what it is. A CT scan is just the beginning.?
For an accurate diagnosis, we have to examine tissue under a microscope. A bronchoscopy allows us to obtain that sample and make a diagnosis. If it turns out to be lung cancer, the tissue we obtain through a bronchoscopy can also be used for molecular profiling, so we can tailor your treatment to any specific genetic mutations. And bronchoscopy can, in addition, sample the lymph nodes to determine the stage of lung cancer.?
Can a bronchoscopy detect tuberculosis??
Yes. Bronchoalveolar lavage is considered the gold standard for detecting any type of lung infection. For patients with pneumonia, we can determine exactly which pathogen is causing it.??
What’s the one thing people should know about bronchoscopies?
Go to a place like MD Anderson which does a large number of complex bronchoscopies each year and has a lot of expertise in them. That level of experience will give you a better outcome.??
MD Anderson is also at the forefront of using ablation therapy during bronchoscopy to treat small, peripheral lung cancers through clinical trials. We are the pioneers in this field, and only a handful of cancer centers offer it right now.??
, is an interventional pulmonologist specializing in bronchoscopies.
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