Cancer is an age-related condition in large part because the immune system declines with age. One of the many important tasks undertaken by the immune system is suppression of cancer. This is achieved by destroying cancerous and potentially cancerous cells quickly, before they can establish a tumor that will go on to subvert the immune system’s normal responses to errant cells. This process of cancer eradication (and tumor development when eradication fails) is enormously complex in detail, but straightforward enough to understand at the high level. How does this interaction between aging, the immune system, and cancer risk work in practice when we are talking about a cancer of the immune system, however? The evidence suggests that persistent viral infection plays a larger direct role here than is the case in most other forms of cancer, which is intriguing given that these viral infections are also likely a major cause of adaptive immune system decline with age.
Immunosenescence is a peculiar remodeling of the immune system, caused by aging, associated with a wide variety of alterations of immune functions. It is has been implicated