i. overview of mammalian thymic development 1. embryology of the mammalian thymus ii. histogenesis of the mammalian thymus 2. the reticulo-epithelial cellular network of the mammalian thymus 3. neuroendocrine influence on thymic hematopoiesis via the reticulo-epithelial (re) cellular network 4. development of lymphopoiesis as a function of the thymic microenvironment 5. the hassalls bodies 6. thymic accessory cells, including dendritic-type antigen presenting cells, within the mammalian thymic microenvironment 7. involution of the mammalian thymus and its role in the overall aging process iii. the thymus and its significance in anti-neoplastic therapy 8. thymic hormones in cancer diagnosis and treatment 9. spontaneous regression of neoplasms: new possibilities for immunotherapy