[Pathogenesis of neoplasms]

The Authors discuss the aspect and the function of the Microcirculatory Unit and the chronic reduction of circulation in true capillaries and therefore of tissue perfusion increasingly evident with the advancement of age, the structural simplification of proteins, the instability of the cells' genome and the increasing remoteness of the immunity system's control. In view of these considerations, they propose the possibility that the onset of tumours may be due to the accentuation of mutageneous substances and the reduction of tissue perfusion with age. When perfusion is maintained of periodically resumed, hypoxy only determines hyperplasia but not cell degeneration or mutations.