what is mantle cell lymphoma |The lymphatic system | What is Hodgkin's lymphoma?

The lymphatic system
What is Hodgkin's lymphoma?


Lymphoma is a cancer that develops at the expense of the body's defense system cells. Two major types of lymphoma are distinguished 
The human body is able to fight outside aggressors like viruses or bacteria and eliminate its own cells when they malfunction.

Hodgkin's lymphomaRepresentation of the lymphatic system.
These missions – recognizing threats and defending the body against them – are ensured by the immune system that relies on the lymphatic system. The latter consists of the lymph nodes (more than 600) and the so-called lymphoid organs such as spleen, bone marrow, tonsils and thymus. The whole is connected by a network of vessels in which the lymph circulates, a liquid constantly filtered by lymph nodes and lymphoid organs. These two types of structures have specialized cells that are responsible for defending the body: white blood cells, or lymphocytes, among which two categories are distinguished.

B lymphocytes produce antibodies capable of binding to intruders. Thus detected, the latter are destroyed by other cells of the immune system. T lymphocytes recognize the infected or abnormal cell and destroy it directly.

LymphomaLymphomas are cancers of the lymphatic system. They are formed by the uncontrolled multiplication of some abnormal lymphocytes.

Two broad categories of lymphoma are distinguished: Hodgkin's disease and non-Hodgkin (NHL) lymphomas. Microscopic analysis of the affected ganglia allows to characterize the type of lymphoma.

The NHL is most often found in people aged sixty years. They form a large group of about 80 diseases. There are two main subtypes: B-type lymphomas, which develop from B lymphocytes and represent 90% of NHL cases, and T-type lymphomas, which develop from T cells.

Hodgkin's disease was described by British physician Thomas Hodgkin in 1832. It affects especially young adults (between 20 and 40 years old). It is characterized by the presence of so-called Reed Sternberg cells that derive from B lymphocytes. Today, specialists prefer to talk about Hodgkin's lymphoma to better emphasize the fact that Hodgkin's disease belongs to the lymphoma family. It represents 15% of the lymphoma.

Different types of Hodgkin's lymphomaThere are two main categories of Hodgkin's lymphoma: Classical Hodgkin's lymphoma and predominantly lymphocytic nodular Hodgkin's lymphoma (or paragranulome of Poppema and Lennert) which accounts for less than 5% of cases. This file deals with classical Hodgkin's lymphoma.

Hodgkin lymphomas in numbersHodgkin's lymphoma is one of the best predicted cancers with a five-year survival rate of 84%. The Health Watch Institute estimated the number of people with classical Hodgkin's lymphoma in 2012 in France at 1 880. Men are more affected than women (1 033 cases versus 847, estimated in 2012). While the number of new annual cases has stabilised since 1990 for men, it increases steadily among women.

Regarding the age of Hodgkin lymphoma, this is a young adult cancer: there is a spike in incidence between 20 and 30 years. Hodgkin's lymphoma also affects more marginally people aged over 60 years.

This dossier was made thanks to the competition of Dr. Pauline Brice, hematologist at the Hôpital Saint-Louis (Paris) and Chair of the Scientific Committee of the Association France Lymphoma Hope.