Sites of Occurrence of Diffuse Large B-Cell Lymphoma

Sites of occurrence

Between the cells of body tissues, there is a transparent yellowish fluid called tissue fluid. This tissue fluid remains between cells, then, due to pressure differences, gathers into lymphatic vessels, and like blood circulating through blood vessels, it circulates throughout the body through lymphatic vessels. The fluid that circulates through these lymphatic vessels is called lymph, or lymph fluid. In the past, it was also called "impa" by borrowing the pronunciation of the Chinese characters.

Along the lymphatic vessels through which lymph fluid flows, there are lymph nodes where lymphocytes, a type of blood cell, gather in nodular clusters. Lymph nodes act as filters that check whether foreign substances that enter or arise within the body are present in the lymph fluid. A good example is the lump that can be felt under the jaw or in both groin areas when there is inflammation. Although they are not nodes in form, the spleen and tonsils, which play functions similar to lymph nodes during the circulation of lymph fluid, are called lymphatic tissue. The lymphatic system is a term that refers collectively to the various parts of the body related to lymph, such as lymph fluid, lymphatic vessels, lymph nodes, and tissues.

· Functions of the lymphatic system The lymphatic system has three main functions. First, it removes excess tissue fluid left in tissues; second, it transports reabsorbed fat components to the blood vessels; and finally, it provides immune defense against foreign substances (such as bacteria and viruses) that do not originate from the body itself.

· Sites of occurrence of lymphoma Lymphoma is a disease that occurs when lymphocytes, which are mainly distributed in the lymphatic system, undergo cancerous changes. Therefore, it most commonly occurs in lymph nodes where lymphocytes are densely concentrated. However, because lymphocytes in the lymphatic system, like blood cells in the vascular system, circulate easily throughout the body, lymphoma can occur in any part of the body. In addition to lymph node lesions, lymphoma can occur in all parts of the gastrointestinal tract as well as in the lungs, liver, heart, and every other part of the body.

In the case of cancers that arise in specific organs, such as colon cancer or lung cancer, cancer cells first develop in a very small area on the surface of the organ at an early stage, then gradually grow and penetrate into the organ. Later, the cancer cells invade the surrounding lymphatic vessels and blood vessels and spread throughout the body via the lymphatic and vascular systems. In contrast, because lymphoma is a tumor that arises in the lymphatic system, cancer cells can circulate throughout the body through the lymphatic system regardless of where they originate. Because of this characteristic, lymphoma is classified not as a solid cancer that occurs in a specific organ, but as a type of blood cancer.

So far, we have explained the sites of occurrence of diffuse large B-cell lymphoma. In the next part, we will look at the types of diffuse large B-cell lymphoma.

Source: Korea Disease Control and Prevention Agency National Health Information Portal