Abstract: Evolving systems of developmental biology might implicate realized events that progress as cell proliferation and spread. Metastases of tumor cells appear to constitute a further characterization of such developmental systems in terms of how integrity of tissues is otherwise further maintained and supported by various contributing cell groups. Component factors appear to constitute a further development in cell biology that allow for the subsequent evolution of malignancy in terms of infiltration of a stroma that is proliferative also. Blood stream spread and lymph node deposits are further characterized as trophic phenomena within evolving contexts of either tumor cell proliferation or of stromal cell participation of such deposits. Only in terms of such evolving cell biologic systems as proliferation and hematogeneous spread can one better understand and delineate modes of interaction of proliferating tumor cells and stroma as integral representations of developmental tissue and cell systems. Differentiation is a constituent event in the evolution of pathways of development that allows for both characterization and phenotypic determination of events of malignant tumor cell proliferation and spread.