[yread]

Histology slides absolutely can tell us a lot about molecular changes, see

https://www.nature.com/articles/s41591-019-0462-y

Of course changes in the genotype that impact the phenotype enough to influence the disease also influence the morphology of the cells.

But this is area of active research so you can't expect phase 3 clinical trials. Yet.

EDIT: here is another more "perspective" paper how such tools could be used and integrated in current processes, from the same authors

https://www.nature.com/articles/s41416-020-01122-x