Chaodynamic loss of complexity and self-similarity in cancer.

'Omnis cellula a cellula': each cell descends from another cell--and most complex organ structures are built up of multiple cells at least. Even the underlying mechanisms of physiological as well as pathological processes reflect complexity in a pronounced manner. Loss of complexity, however, has been detected in aging and apparently also in the case of a number of diseases. This paper describes the loss of complexity in both carcinogenesis and the related growth pattern of cancer. After disruption of the cell's stability as a result of mutations, a decrease in the ability of the cell to induce a self-organized response is associated with the loss of control parameters at the cellular and molecular level. Complexity, understood as a principle of order, is altered in certain malignant tumors, as is indicated by a loss of the golden mean and by the disappearance of self-similarity. The lack of self-similarity could, therefore, be an ideal practical marker of malignancy in medical image analysis.