  Hot spots in tumors are regions of high vascular density in the center of the
tumor and their analysis is an important diagnostic tool in cancer treatment.
We present a model for vascular remodeling in tumors predicting that the
formation of hot spots correlates with local inhomogeneities of the original
arterio-venous vasculature of the healthy tissue. Probable locations for hot
spots in the late stages of the tumor are locations of increased blood pressure
gradients. The developing tumor vasculature is non-hierarchical but still
complex displaying algebraically decaying density distributions.
