Simulation of tumor necrosis in primary melanoma.

Melanoma ulceration is an adverse prognostic finding. The tumor thickness and overgrowth of the tumor necrotic center are the principal factors of ulcer development. We present here the results of computer simulation of necrotic core formation by employing supermodeling approach, which consists in coupling of a few melanoma models differing in values of an important parameter responsible for tumor dynamics. We show that due to remodeling of skin vascularization by growing cancer, and insufficient necrotic material removal, we can observe development of spike-like structures of massive necrotic center growing mainly in a vertical direction. It starts from the skin surface and proliferates to its deeper layers. We show that cone shaped melanoma, resembling nodal melanoma (NM), produces larger necrotic center than flatter tumors types. This agrees well with clinical observations what is an important argument in favor of supermodeling concept.