There are many answers. Overall, general concepts like neuronal networks are tailored and packaged to specific data situations and purposes. Perhaps one good example is drug response prediction, where such tools are trained on genomic features of model organisms such as cancer cell lines to predict patient-specific cancer drug response (very broadly speaking here).

Seems like you are in the hands of capable clinicians - I simply wish you all the best.

Just fyi, this was most likely because of certain dyes that are used in patholgy labs. Cells by themselves are colourless unless they contain specific pigments - like black-ish melanocytes.

https://en.m.wikipedia.org/wiki/H%26E_stain

Hope that cancer is gone now.