Do we know what causes lymphoma of the skin?
In most patients with non-Hodgkin lymphoma of the skin, the cause of their cancers is unknown.
Scientists now understand how certain changes in DNA can cause normal lymphocytes to become lymphoma cells. DNA is the chemical in each of our cells that makes up our genes – the instructions for how our cells function. We usually look like our parents because they are the source of our DNA. But DNA affects more than just how we look.
Some genes contain instructions for controlling when our cells grow, divide into new cells, and die at the right time. Certain genes that help cells grow, divide, or live longer are called oncogenes. Others that slow down cell division or cause cells to die at the right time are called tumor suppressor genes. Cancers can be caused by DNA changes that turn on oncogenes or turn off tumor suppressor genes.
Some people inherit DNA mutations (changes) from a parent that increases their risk of developing some types of cancer. But non-Hodgkin lymphoma is not one of the cancer types often caused by inherited mutations.
DNA changes related to non-Hodgkin lymphoma are usually acquired after birth, rather than being inherited. Some of these acquired changes may have outside causes, but often they occur for no apparent reason. They seem to happen more often as we age, which may help explain why lymphomas usually occur in older people.
Each time a cell divides into 2 new cells, it must make a copy of its DNA. This process is not perfect, and sometimes copying errors occur. Cells have repair enzymes to help fix these errors, but some may slip past, especially if the cells are growing rapidly.
The DNA in each human cell is packaged in 23 pairs of chromosomes. Changes in chromosomes are sometimes seen in skin lymphoma cells, but there is no single chromosome change that is common to all skin lymphomas. In some cases, part of one of the chromosomes is lost (known as a chromosomal deletion). Translocations, in which DNA from one chromosome breaks off and becomes attached to a different chromosome, are another type of change seen in some skin lymphomas. When these types of chromosome changes happen, oncogenes can be turned on or tumor suppressor genes can be turned off.
Scientists are learning about the exact genes involved in this process and how they may cause lymphoma and other cancers. This information is being used to develop new tests for detecting and classifying certain types of non-Hodgkin lymphoma, as well as for developing new treatments.
Even though researchers have found some of the key DNA changes that cause lymphoma, they still do not know why these changes occur.
The immune system seems to play an important role in some cases of lymphoma. People with immune deficiencies (due to inherited conditions, drug treatment, organ transplants, or HIV infection) have a much greater chance of developing lymphoma than people without an immune deficiency.
Last Medical Review: 03/14/2013
Last Revised: 02/11/2014