Hodgkin lymphoma is caused by a change in the DNA of a B-cell lymphocyte. This mutation causes a large number of abnormal and oversized B cells to accumulate in the lymphatic system, and, over time, spread to other organs. It is not clear what causes DNA mutation.
Source : Derma NZ
Although the trigger causes are generally unknown. various factors have been identified which lead to increased risk of developing Hodgkin lymphoma (HL). They include :
More Information about HL US NIH National Cancer Institute