Carcinoma is another medical term for cancer; specifically for cancer that has developed in epithelial cells. In the case of lung cancer there are two principal types. Small cell lung cancer (SCLC) accounts for about 15% of all cases. The other 85% is comprised of non-small cell lung cancer, a catch-all term for lung cancers generated by several different types of malignant cells. Carcinoma of the lung is the most common form of cancer in the United States, with over 200,000 new diagnoses each year. While the rate of incidence is dropping because of the drop in cigarette consumption, lung cancer remains the most frequent cause of death due to malignancy.
Small Cell Lung Cancer
Small cell lung cancer SCLC) represents a small portion of the number of cancer cases diagnosed annually; it is noted for its rapid rate of growth and poor rate of recovery. The “small cell” referred to here is called an oat cell, significant for its small size, oval shape and relative lack of cytoplasm. Most cells contain a substantial amount of cytoplasm, a substance that holds all of the cell’s components except for the nucleus.
SCLC is heavily linked to smoking; some 98% of all cases diagnosed occur in patients with a history of smoking. It is also linked to on-the-job exposure to toxic substances, notably asbestos. Workers who have been exposed to asbestos products and inhaled asbestos fibers as a result can develop two principal types of carcinoma: mesothelioma, which rises in the membrane that lines the lungs, the abdominal cavity, and the heart; or lung cancer. A significant proportion of small cell lung cancer cases are believed to be associated with asbestos exposure.
The oat cells unique to this type of carcinoma are known for their rapid rate of multiplication, and also for their tendency to migrate to distant parts of the body relatively early in the course of the disease. In many cases the patient with SCLC exhibits no symptoms associated with lung cancer until it has spread beyond the tumor in the lung. For this reason 65% – 70% of all SCLC diagnoses occur after the disease has metastasized, putting it in an advanced stage before treatment has started.
Non-Small Cell Lung Cancer
Carcinoma of the lung is more commonly developed with non-small cell forms. There are several types of cells that can develop malignant properties: epithelial cells, sarcomatoid cells, squamous cells, and others. A carcinoma, however, is defined as a form of malignancy arising from epithelial cells, which line the inner and outer surfaces of the body. As with SCLC smoking is the most common cause of non-small cell lung cancer; there is also a link to industrial toxins exposure including asbestos. In the UK 2 – 3% of all lung cancer cases from 1980 – 2000 are attributed to asbestos. Non-small cell lung cancer is the category of the disease most often seen by oncologists; however treatment protocols will differ based on the type of cell associated with each case.
The symptoms associated with all forms of lung cancer include chest pain, a persistent cough, shortness of breath, coughing up blood, hoarseness, and difficulty swallowing. There are also nonspecific symptoms such as bone pain, fever, weakness, and weight loss that are often observed in lung cancer patients but may have to do with other health problems combined with the cancer. Many of the individuals diagnosed with lung cancer are of retirement age and their health histories have grown more complicated with time.