Lung Cancer Types

Lung cancer is a disease involving neuroendocrine cells that go through certain changes causing them to grow too much, forming tumors. The American Cancer Society cites four types of neuroendocrine tumors that develop in the lungs. These tumors include: small-cell cancer, large cell neuroendocrine carcinoma, atypical carcinoid, and typical carcinoid. Lung cancer is a more general classification including all types of tumors that concern it. To make things simpler there are two main types of lung cancer, non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). The naming refers to how the cancers look when viewed under a microscope, however, the patient’s understanding of their specific type goes beyond microscopic views. Despite falling under the universal term of “lung cancer” the distinction between these two types is paramount, as each maintains differences in treatment options and prognosis. Despite their differences, both types of lung cancer can be traced to the same carcinogens. Research shows that tobacco smoking accounts for a majority of cases. However, exposure to materials such as asbestos is also a known cause. Asbestos is a human carcinogen once used for insulation in factories, shipyards, and other industries. Since the 1970s the government has regulated against it. Inhalation of asbestos can lead not only to lung cancer, but mesothelioma, and other non-cancerous illnesses. Once a patient has been diagnosed with lung cancer their particular type will influence their doctor as to what course of treatment to take. In order to better understand the differences between NSCLC and SCLC they are detailed below:
  • Small-cell lung cancer- Comprising approximately 20 percent of all lung cancers, SCLC, as the name suggests, are small cells that multiply quickly. This rapid multiplication is aggressive and causes large tumors to form. It typically develops in the central areas of the lung. Because of how quickly it can metastasize; it usually spreads to other parts of the body. Current or former smokers make up almost all of the patients diagnosed with SCLC.
  • Non-small-cell lung cancer- NSCLC is the more prominent type of lung cancer, occurring in about 80 percent of patients.  Due to its vastness, this type of lung cancer has been subdivided into four types:
    • Squamous Cell Carcinoma- This is the most common type of NSCLC, forming in the lining of the bronchial tubes. Overall, it is the most common type of lung cancer exhibited in men. It can also be referred to as epidermoid carcinoma.
    • Adenocarcinoma- Commonly found among woman and people that have not smoked, this cancer is located in the glands of the lungs that are responsible for producing mucus.
    • Bronchioalveolar Carcinoma- This is a more rare form of cancer and is a subset of adenocarcinoma. This subset generally forms near the lung’s air sacs. It is listed by as the type of NSCLC most likely to respond to newer targeted therapies.
    • Large-cell undifferentiated carcinoma- A rapidly growing cancer that usually forms near the surface or outer edges of the lungs.
As previously mentioned the type of lung cancer is a determining factor in both treatment and prognosis. The two types vary in the number of patients diagnosed, as well as causation. Research indicates that one of the causations linked to diseases such as lung cancer and mesothelioma is exposure to asbestos. References: