Lung cancer results in more fatalities in the United States than any other kind of cancer. About 230,000 new cases of lung cancer are diagnosed annually, and about 160,000 lung cancer patients do not survive for more than five years. Smokers have the greatest risk of developing lung cancer, and quitting smoking greatly reduces this risk. The risk of fatality from lung cancer is increased substantially if the patient begins or continues to smoke after being diagnosed.
Symptoms of Lung Cancer
Whether or not screening for lung cancer is actually helpful is controversial. Some doctors feel that screening reveals conditions which are not harmful, and investigating these conditions exposes the patient to unnecessary risks. In many cases doctors will only begin testing for lung cancer if the patient is showing symptoms.
Symptoms that may alert physicians to the possibility of lung cancer include:
- Chronic cough
- Coughing up blood
- Chest pain
- Wheezing
- Hoarseness
- Unexplained weight loss
- Chronic headaches
- Bone pain
Diagnosis and Misdiagnosis of Lung Cancer
Imaging Tests
Doctors may use imaging tests as a first step in detecting lung cancer. Imaging tests include X-rays, CT scans, MRIs, and PET scans. If a mass or lump appears in any of the images, further testing may be done to verify the presence of lung cancer. Physicians that rely too heavily on imaging techniques to detect lung cancer may misdiagnose patients. A mass can be non-cancerous, and prescribing treatment or surgery without further examination can be unnecessary and possibly harmful to the patient.
Sputum Tests
If a patient has a cough that is producing sputum, examination of the sputum will sometimes reveal lung cancer cells. This type of testing can eliminate the need for more invasive diagnostic tests, and save time in beginning treatment. While sputum testing is more convenient than most other types of lung cancer testing, it may not always be effective. Cells may be altered or damaged due to inflammation, and may appear to have mutations that pathologists can misinterpret as cancerous cells. Cells may also show no signs of cancer, even if cancer is present in the lung tissue.
Bronchoscopy
Examining the lungs using bronchoscopy involves inserting a thin tube with a tiny camera on it through the nose or mouth and into the airways. A tumor that is present in the lungs or airways can be viewed this way, and tissue can be obtained for a biopsy. This type of testing is very accurate, but it is invasive, and patients may cough up blood for days afterwards. In some cases, patients may suffer severe bleeding, heart arrhythmias, and decreased levels of oxygen in the blood following a brochoscopy.
Biopsy
A sample of tissue is often removed from the lungs using a fine needle along with radiological imaging to provide visual feedback. In some cases this method is necessary to reach tissue not accessible by bronchoscopy. This procedure can have complications. In some cases, the needle will cause a small air leak in the lung. Misdiagnosis can also occur if the tissue is not taken from the correct part of the airways. The results of the biopsy can also be misdiagnosed by pathologists.
Conditions Commonly Misdiagnosed as Lung Cancer
When testing for lung cancer, physicians should also test for these conditions as possible alternative diagnoses:
- Lymphoma
- Tuberculosis
- Lung nodules
- Bronchial Pneumonia
- Thoracic Hodgkin Disease
- Lung Abscesses
- Encysted lung Effusion
Unfortunately, sometimes a physician will suspect lung cancer and wish to begin treatment as soon as possible, before cancer spreads. In many cases, one of the above conditions is causing symptoms that may be similar to lung cancer. Beginning lung cancer treatment when it is in fact a different condition causing symptoms or showing as a mass on an x-ray can be harmful to the patient. The condition is being allowed to worsen as the patient is undergoing unnecessary treatment. Radiation therapy or chemotherapy can also harm healthy cells and subject a patient to unnecessary suffering in the case of a misdiagnosis.
Alternatively, these conditions may be misdiagnosed when in fact the cause of symptoms is lung cancer. In this case the patient’s lung cancer will be allowed to spread while taking unnecessary medications or undergoing unnecessary treatments, making the cancer harder to treat if or when it is detected. In some cases, the patient may die from the lung cancer before it is correctly diagnosed.
Sources:
“Lung Cancer.” American Cancer Society. American Cancer Society, 12 Jul 2013. Web. 13 Nov 2013. <http://www.cancer.org/cancer/lungcancer-non-smallcell/detailedguide/non-small-cell-lung-cancer-key-statistics>.
“Lung Cancer.” Mayo Clinic. Mayo Foundation for Medical education and Research, 13 Jul 2013. Web. 13 Nov 2013. <http://www.mayoclinic.com/health/lung-cancer/DS00038/DSECTION=treatments-and-drugs>.
“Lung Cancer.” National Cancer Institute. U.S. Department of Health and Human Services, n.d. Web. 13 Nov 2013. <http://www.cancer.gov/cancertopics/types/lung>.
“Misdiagnosis of Lung Cancer.” Right Diagnosis. HealthGrades, 07 May 2013. Web. 13 Nov 2013. <http://www.rightdiagnosis.com/l/lung_cancer/misdiag.htm>.