Melanoma Controls the Metastatic Process only in Terms of Metastatic Cell Dissemination - What Is Responsible for Metastatic Cell Proliferation?

Abstract

The process of melanoma metastasis can be divided into two stages of metastatic cell dissemination and proliferation. The whole process should be observed and distinguished through the variable or prism of time. The fact that melanoma metastases are detected in visceral organs at the stage when they are macroscopically visible does not imply that their onset has occurred much earlier. Additionally, it is quite obvious that the entire process is not driven by melanoma but rather only the initial stage of metastatic cell dissemination, whereas the later stage of metastatic cell proliferation is driven by other factors, firstly by mutated genes in the presence of melanoma or without it. Dissemination of metastatic cells occurs at approximately the same time in all melanomas, at MIS transition to MM, but is not immediately followed by metastatic cell proliferation; instead, some time has to elapse for a particular gene mutation to occur, and this timing varies among melanomas. Following dissemination of metastatic cells to visceral organs, they remain inactive, and in this period the presence of melanoma is not necessary anymore for metastatic cell proliferation, as they are waiting for a signal to start multiplying. This is clearly discernible from the fact that melanoma is today detected and removed frequently and early, but visible metastases then develop in the absence of melanoma, which may also regress spontaneously. Accordingly, MM is no longer necessary for metastasis later on. Finally, let me rephrase the title: melanoma is only responsible for initial dissemination of metastatic cells, whereas subsequent proliferation of metastatic cells is driven by other factors, most probably mutated genes.