I have four plots, three of them ggsurvplot objects, that I need to compose into a single 2x2 facet plot. I am blocked because it appears that there is no automatic way to convert a ggsurvplot to a grob, as appears to be required for me to combine them using gridextra. The four plots are also saved as pdf figures, but these also seem not to be importable as grobs. They should all be vector graphics.
Any suggestions as to how I can convert the ggsrurvplot objects into grobs?