Urban Malignancy: Similarity in the Fractal Dimensions of Urban Morphology and Malignant Neoplasms

All contemporary landscapes on the planet feature the aggressive growth of cities and other urbanizations. In 1990, we suggested that the similarity between urban forms and malignant lesions could be studied with the use of fractal geometry. Two separate disciplines have emerged since then: the study of urban morphology using various fractal analyses, and "oncological mathematics," the study of malignant lesions using fractal analysis. Several mathematical techniques are used in both fields to conduct these studies. From the point of view of a physician, the expanding, invasive, colonizing urban form with highly irregular borders resembles a malignant lesion. Malignant neoplasms have at least four major characteristics: rapid, uncontrolled growth; invasion and destruction of adjacent normal tissues (ecosystems); metastasis (distant colonization); and de-differentiation. Many urban forms are almost identical in general appearance, a characteristic that would qualify as "de-differentiation." Large urban settlements display "rapid, uncontrolled growth" expanding in population and area occupied at rates of from 5 to 13% per year. We propose a null hypothesis that "there is no similarity or correlation in the fractal dimension of urban forms and malignant neoplasms."