The article just says that having an abortion would have "extended her life" but it isn't clear to me whether that means they could have cured her or just provided her with a few extra weeks/months of life.
I mention this because I think if I were in a similar situation I would make the same decision if the only difference was a few weeks/months but I might make a different choice if I knew there was a real possibility for a cure from the cancer and forgoing treatment meant leaving the children I already have.
I'm not trying to start an argument but I often wonder how I would react in similar circumstance. It's much easier for me to talk about hypotheticals when there's no real cost involved. It would be supremely difficult for me to voluntarily travel a path that I knew would permanently separate me from my kids.
I think you missed the whole point.
She allowed God to decide. She didn't try to "play God" and calculate how long her life was going to be or how she might be able to "manage" things on her own.
She left it in God's hands.
Though I see your point about "extend," it's likely that the reporter used that term because a cure wasn't certain. I'd say, however, that it wouldn't have been a bone of contention with the docs if they were talking about a few months.