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one of the most dangerous and virulent diseases, which causes the tumor of the
lung, is considered to be lung cancer.
To understand what lung cancer may lead to, one should be aware of the functions and the structure of the lungs.
The lungs can be compared with a sponge, into which air is drawn and carbon
dioxide is removed. A distinctive feature of the lungs is a smaller size of the
left lung, compared to the right one. Such a structure of the left lung provides
sufficient space for the heart. At the same time if the right lung comprises
three rounded parts, called lobes, the left lung has only two.
In most cases lung cancer starts in the layer of tissue on the inside of the
bronchi, the major air passages of the lungs which diverge from the trachea.
According to the look of the cells under a microscope two main types of lung cancer are distinguished:
1) Small Cell Lung Cancer
2) Non-small Cell Lung Cancer.
The clinical courses of different lung cancer types are specific, that is why their treatment should be specific as well.
1) Small cell lung cancer (SCLC) (Other Names: Small Cell Undifferentiated Carcinoma, Oat Cell Cancer)
As one could guess under a microscope SCLC cells look rather small. As the disease progresses these small cells increases greatly in amount and could spread to the lymph nodes and other organs by metastasis. The cells could affect brain, liver and bones.
Nowadays cases of small cell lung cancer number about 20 percent of all lung cancers and happen comparatively not as common as cases of non-small cell lung cancer.
2) Non-small Cell Lung Cancer (NSCLC)
The commonest type of all lung cancers is non-small cell lung cancer. It occurs in 80 percent of lung cancer cases. The typical feature of NSCLC is slow dissemination of tumor cells versus small cell lung cancer.
According to the type of a cell, in which the cancer progresses, three types of non-small cell lung cancer are distinguished:
1) Squamous Cell Carcinoma (or Epidermoid Carcinoma) is a malignant tumor of squamous epithelium, the most superficial layer of which consists of very thin, flattened cells, called squamous cells. They are situated in the passages of the digestive system and the respiratory tract, in the uppermost layer of the skin and the inside surface of the hollow organs. The usual reason of this lung cancer type is smoking, that’s why it’s found typically near bronchus.
2) Adenocarcinoma is a malignant tumour formed from glandular structures in epithelial tissue. In most cases adenocarcinoma NSCLC is found in the outer area of the lung. viagra canada
3) Large-cell undifferentiated carcinoma. The typical feature of this type of
lung cancer is an abnormally large size of cells. Large-cell undifferentiated
carcinoma progresses rather quickly and could be discovered in any area of the
lung.