In general, this is very likely that it will require machine learning. Tissue studio is fair choice if you have a lot of money >60k per 3 years. You might look at ilastik. It is much simpler and limited, but it is free. Also some other "digital pathology" software might be of use, but again, they usually cost money.

These xenografts has been ex-planted and now stained? All is now in phase of post-processing of the final micronecroses.  I would use histochemistry techniques rather then H&E staining, if you can still do this to answer this question. H&E might be too crude for this purpose. You might miss developing micronecrosis when not using more specific necrosis or apoptosis markers.

Have you done any measurements assessing these during in-vivo that you can later use to make any correlations?  

Hi, thanks for all the answers.

I have multiple time points and serial staining with more markers, for hypoxia and apoptosis. The goal is not to measure absolute necrosis, but to measure the distance between blood vessels and edge of necrosis in a reliable, user-independent way.

I can narrow down this measurement to necroses of certain size, so long I have enough measurements to have