Purpose: The incidence of prostate cancer dramatically increases with age. The etiology still awaits elucidation, and the question as to why it is so prominently a disease of aging remains unanswered. We offer an explanation by suggesting an age related deficient immune surveillance.
Materials and methods: Reports published in the scientific literature with relevance to cancer and immunity, immune senescence, blood-prostate barrier and immune privilege were identified using MEDLINE.
Results: The existence of a blood-prostate barrier is a fair assumption, and the prostate may be considered an immune privileged site. With aging the prostate, a priori immunologically under surveilled, probably becomes more and more so. There is impaired function, transmigration and probably penetration into the gland of natural killer and other immune competent cells due to the onset of immune senescence coupled with impaired diapedesis and possible age related alterations in the blood-prostate barrier.
Conclusions: Apparently, with aging the immune surveillance of the already immune privileged prostate is progressively and further affected. This condition may result in the inability of the gland to eradicate emergent malignant cells.