Lung cancer is the second most common cancer in the United States, with over 200,000 new diagnoses. It’s also the leading cause of cancer death each year. Though is smoking the most significant contributing risk factor for this diagnosis, studies estimate that about 3 – 4% of lung cancer diagnoses are asbestos-related.
Asbestos and Lung Cancer
Lung cancer is often associated with some exposure to toxic substances. The vast majority of cases are caused by smoking, but the second leading cause is radon exposure. Though not nearly as many cases have been linked to asbestos exposure, research has suggested that asbestos-related lung cancer is more prevalent than we realize.
Asbestos exposure often occurs in the workplace, but it can also happen at home due to construction projects or deteriorating asbestos products or secondhand exposure. No amount of asbestos exposure is considered safe, though researchers note that the duration of exposure puts people at a higher lung cancer risk. Once the asbestos is inhaled, our body cannot remove the toxin, and the asbestos fibres can cause damage over time and develop into asbestos cancer.
Many people confuse mesothelioma and lung cancer since most mesothelioma cases affect the lungs. But malignant mesothelioma develops when the asbestos fibres scar and lead to tumours in the lining of the lungs, the mesothelium. Mesothelioma can also first develop in other parts of the body, like the abdominal cavity or lining of the heart. In cases of asbestos lung cancer, the fibres become lodged in the lung tissue, which can also cause irritation and scarring over time that can develop into tumours. Asbestos can cause any type and subset of lung cancer, including non-small cell lung cancer and small cell lung cancer.
Diagnosing the Symptoms of Asbestos Lung Cancer
All asbestos cancers and asbestos-related diseases take time to develop. The fibres cause health effects like inflammation and scarring over a decade or longer. Asbestos-related lung cancer, in particular, has a latency period of 15 – 35 years on average.
When asbestos-related, the symptoms that first present for lung cancer are primarily the same as other asbestos diseases. Some of the differences between these asbestos cancers and how they may present can be attributed to where and how the tumours form. In mesothelioma, for instance, the tumours often create a sheath-like formation across the pleura and other impacted areas, as the cancer cells are known to grow and spread rather quickly. Lung cancer, however, often sees tumours form in more defined areas of the lung initially, though it is also known to be relatively quick to spread and grow in the body. Common Symptoms of Asbestos-Related Lung Cancer
- Persistent cough
- Chest pain
- Difficulty breathing or shortness of breath
- Coughing up phlegm or sputum (mucus from the trachea and bronchi)
- Weight Loss
Like mesothelioma, lung cancer associated with asbestos exposure may be difficult to detect early because of the long latency and often nonspecific symptoms. These difficulties can lead to misdiagnosis, which ultimately delays treatment.
Diagnosis usually starts with an imaging scan, like an X-Ray or CT scan, which can show any abnormalities in the lungs. The X-Ray may show any masses or nodules in the lung, while a CT scan may be the next step to have more advanced imaging of lesions in the lungs that may not appear in an X-Ray.
After initial scans, your doctor may perform sputum cytology, if applicable, a test that will look at the cells of sputum (mucus from the respiratory tract that usually implies infection or disease). The sample may reveal cancerous cells in patients producing and coughing up sputum. Some patients who show a fluid build up in the lungs (pleural effusion) may also undergo thoracentesis, which takes a fluid sample to test for lung cancer cells.
A biopsy or tissue sample will generally be required to confirm the lung cancer diagnosis. There are several procedures your doctor can use to get the piece depending on what part of the lung shows signs of cancer. One of the more common procedures is a bronchoscopy, which can examine tumours or blockages in the larger airways. With this procedure, a tube is passed through the mouth or nose into the windpipe to the bronchi, and We can then use smaller instruments to collect tissue and cell samples.
Once the diagnosis is confirmed, your doctor may run other tests to develop better a treatment plan to determine the stage or extent of cancer.
Asbestos-Related Lung Cancer Survival Rates
Lung cancer prognosis and survival rates vary widely depending on the type and stage of diagnosis. According to the National Cancer Institute, about 18% of lung cancer patients survive five years. Though this statistic isn’t very encouraging, only 9% of mesothelioma patients live five years or more after diagnosis.
Treating Asbestos Lung Cancer
Treatment for mesothelioma, lung cancer and other asbestos cancers typically rely on a multimodal approach dependent on the stage of the disease. Like mesothelioma, lung cancer is often treated with conventional surgery, chemotherapy and radiation therapy.
For patients diagnosed with early-stage asbestos-related lung cancer, surgery followed by chemotherapy is considered the standard of care. The type of surgery depends on how localized the tumours are. Surgery can range from removing a small section of a lung to the entire lobe of a lung or even a pneumonectomy which entails the removal of the whole lung. A pneumonectomy or extrapleural pneumonectomy is also a standard treatment for pleural mesothelioma.
Doctors have also been able to perform less invasive procedures for lung cancer with technological advancements in recent years. For instance, video-assisted thoracoscopic surgery (VATS) has become more common for eligible patients and allows for a shorter recovery period and fewer potential complications.
Patients eligible for surgical resection often undergo chemotherapy and radiation therapy. Unfortunately, most patients are diagnosed at a more advanced stage where surgery isn’t an option. In these instances, chemotherapy and radiation are the typical courses of treatment for those in the final stages of the disease, Who may apply these treatment options palliatively to improve their quality of life.
The FDA has also approved emerging treatments like immunotherapy to treat lung cancer since clinical trials proved the treatment to be safe and effective. Since 2015, immunotherapy drugs Opdivo (nivolumab) and Keytruda (pembrolizumab). And TECENTRIQ (atezolizumab) has been FDA approved to treat non-small cell lung cancer. There are still ongoing clinical trials for these and other immunotherapies alone and in combination with other treatments, hopefully bringing researchers closer to finding a cure.
Source Link: https://www.mesothelioma.com/asbestos-cancer/lung-cancer/
Cancerous (malignant) mesothelioma is the most common form, usually affecting the lungs.