Definition and etiology
Hodgkin lymphoma (also known as Hodgkin’s lymphoma, Hodgkin’s disease, Morbus Hodgkin and lymphogranulomatosis) is a malignant disease of the lymphatic system. It was first described in 1832 by Sir Thomas Hodgkin, after whom it was named.
The characteristic histological changes that are associated with Hodgkin lymphoma, the disease-defining Hodgkin cells and Reed-Sternberg cells, were first described in 1898 by Carl Sternberg and in 1902 by Dorothy Reed. These cells are only present in Hodgkin lymphoma and thus distinguish Hodgkin lymphoma from the large group of non-Hodgkin lymphomas and other diseases of the lymphatic system.
Since the discovery of these cells and until today, different potential causes and mechanisms for the development of Hodgkin lymphoma have been discussed.
It was only in recent years that new molecular-biological methods provided evidence that malignant Hodgkin cells originate from B-lymphocytes produced in the germinal center of lymph nodes.
The development of Hodgkin lymphoma is supposed to be promoted by the Epstein-Barr virus (EBV) because patients who once had an infectious mononucleosis (Pfeiffer’s disease), which is caused by an EBV infection and manifests itself as acute feverish disease accompanied by lymph node swellings, are more often affected by Hodgkin lymphoma than patients who never had this kind of infection. This is supported by a discovery made at the end of the 1980s, when genetic material of the Epstein-Barr virus was found in Hodgkin cells and Reed-Sternberg cells.
However, there are also malignant Hodgkin and Reed-Sternberg cells in which no DNA of the EBV can be detected. Besides, the vast majority of EBV-infected people never develop Hodgkin lymphoma (more than 95% of the population become infected with the Epstein-Barr virus during the first 30 years of their life, most of them without showing any clinical signs). For these reasons, there must be other factors causing or contributing to the development of Hodgkin lymphoma. Potential influencing factors that are currently being discussed are, above all, a disturbed regulation of the immune system as well as genetic aspects and environmental influences.