Summary

As more is learned about the role of the nervous system, it is becoming apparent that the nervous system plays a relatively important role in a large number of human tumors. However, as the available data suggest, it is clear that the mechanisms and pathways used by the nervous system to stimulate tumorigenesis and tumor growth differ between tumor types. For example, it is clear from published data that the effect of different parts of the autonomic nervous system on different tumor types is specific. However, there are also tumors in which the sympathetic nervous system is active in the initiation phase, and the parasympathetic nervous system stimulates tumor progression later on, for example, prostate cancer. In addition, there are also tumors whose growth is especially stimulated by the parasympathetic nervous system, as is the case, for example, with stomach tumor. It is not entirely clear what determines these differences in the effect of the sympathetic and parasympathetic nervous systems on the initiation and growth of tumors. However, it can be assumed that one factor will be the different effects of the components of the autonomic nervous system on cell and tissue homeostasis in different tissues already under physiological conditions. In some tissues, the trophic action of the sympathetic dominates, and in other tissues, the action of the parasympathetic may predominate.