Causes and classification of non-small cell lung cancer

What are the classifications of non-small cell lung cancer? Non-small cell lung cancer is also a classification of lung cancer. Because this type is more common, there are more treatment methods. This is really a great benefit for lung cancer patients and their families. So what are the classifications of this type of lung cancer? Let us introduce it.

Classification of non-small cell lung cancer:

There are many ways to classify lung cancer. According to its many characteristics, they can be divided into different categories. This disease mainly occurs in the bronchial mucosal epithelium. There are many ways to classify lung cancer. According to different classification methods, lung cancer can be divided into different types. According to histology, it can be divided into: small cell lung cancer and non-small cell lung cancer (squamous cell carcinoma, adenocarcinoma, large cell carcinoma); according to anatomical location, it can be divided into: central lung cancer and peripheral lung cancer, and according to the origin of the tumor, it can be divided into primary lung cancer and secondary lung cancer.

1. Classification by anatomical location

1. Central lung cancer: Lung cancer that occurs above the segmental bronchus to the main bronchus is called central lung cancer, accounting for about 3/4, with squamous cell carcinoma and small cell undifferentiated carcinoma being the most common.

2. Peripheral lung cancer: Lung cancer that occurs below the segmental bronchus is called peripheral lung cancer, accounting for about 1/4, with adenocarcinoma being the most common.

(II) By histological classification:

Based on the degree of differentiation and morphological characteristics of each type of lung cancer, lung cancer is currently divided into two major categories, namely small cell lung cancer and non-small cell lung cancer, the latter of which includes squamous cell carcinoma, adenocarcinoma, and large cell carcinoma.

1. Small cell undifferentiated carcinoma (abbreviated as small cell carcinoma):

This is the most malignant type of lung cancer, accounting for about 1/5 of primary lung cancer. The patients are relatively young, mostly around 40 to 50 years old, and have a history of smoking. It is prone to occur in the large bronchi near the hilum of the lung, tends to grow submucosally, often invades the extrabronchial lung essence, and easily merges with the hilar and mediastinal lymph nodes to form masses. Cancer cells grow fast, have strong invasiveness, and metastasize early to distant organs, often metastasizing to the brain, adrenal glands, liver, bones and other organs. This type is more sensitive to radiotherapy and chemotherapy. Cancer cells have a variety of forms, such as lymphoid, oat-like, spindle-shaped, etc., which are divided into oat cell type, intermediate cell type and composite type. Immunohistochemistry and special tumor markers are considered to be neuroendocrine tumors.

2. Squamous cell carcinoma (abbreviated as squamous cell carcinoma):

It is the most common type, accounting for about 40% to 50% of primary lung cancers. It is more common in elderly men and is closely related to smoking. Central lung cancer is more common and tends to grow into the lumen, often causing bronchial stenosis, atelectasis, or obstructive pneumonia in the early stage. Cancerous tissue is prone to degeneration and necrosis, forming cavities or cancerous lung abscesses. Squamous cell carcinoma grows slowly and metastasizes late, so there are relatively more chances for surgical resection and a better 5-year survival rate, but it is not as sensitive to radiotherapy and chemotherapy as small cell undifferentiated carcinoma.

Squamous cell carcinoma cells are large, polymorphic, and have a tendency to keratinize. There are many intercellular bridges, and they are often arranged in a squamous epithelial pattern. Electron microscopy shows that there are desmosomes connecting the cancer cells and tension microfilaments attached. Sometimes squamous cell carcinoma and adenocarcinoma are mixed, which is called mixed lung cancer (squamous adenocarcinoma). There are also other mixed types.

The above introduces the classification of non-small cell lung cancer. It can be divided into different types according to different parts. It can be seen that lung cancer is really harmful to humans. No matter which type of lung cancer, it can cause great harm, so you must actively treat it so that you can get a healthy body.