Aging, cancer, and cancer vaccines

Elderly patients represent a unique and challenging group of patients to the practicing oncologist. They represent a heterogeneous group in terms of comorbidities and functional status which makes it difficult to establish management recommendation. One of the cancer pathways that is of interest in the elderly is the immune system and its role in oncogenesis and as potential therapeutic targets. In this review we present an overview of the changes in the immune system and the use of cancer vaccines in the elderly. We will also discuss the assessment of elderly patient with cancer.Aging is a process characterized by progressive functional decrease in all organs, morphological changes, and immune system-related changes at the cellular and molecular levels, which determine less adaptive biologic functions. The immune system alterations in the elderly are comprehensively known as immunosenescence [1]. This phenomenon is characterized by an accumulation of changes that progressively results in dysfunctional or compromised immune responses [2,3]. Multiple aspects are involved: thymic involution [1], shifts in the number, distribution, and activity of T- [4] and B-lymphocytes [5-10], reduced availability of na？ve CD4+ and CD8+ T-cells [1] and impaired production of na？ve B-cells in bone marrow [11-13], dysfunction of antigen presenting cells (APCs) [3], alterations in cytokines production [9-13], frequent oligoclonal and monoclonal immunoglobulin production [10-23], skewing of B cell production to CD5+ B cells that are more likely to generate auto-antibodies [11-15].In detail, overall diversity of the total T-cell repertoire is skewed by oligoclonal expansions of memory CD4+, CD8+[10-23] and CD95+ T-cells, and a limited production of na？ve cells. Additionally, the increased memory and activated effector CD8+ T-cells [24,25] show a restricted TCR repertoire diversity, have shorter telomeres [26] and a limited proliferative potential [27]. They are largely represented by clo