Oh wow, I didn't even know she was sick.
Donna Summer was one of the very few pop artists I listened to when I was a kid. My parents had all of her albums and in my opinion they were mostly forgettable, but "Live and More" somehow got a hold of me and never let go. I played that album pretty often and was mesmerized by that long version of MacArthur Park (an entire album side - 18 minutes). For some reason they removed that song from the CD release years later, but it's available again on "The Dance Collection".
RIP. Very sad news.