[mrabcx]

How could it be inoperable if a human controlled robot managed to remove it?

[srean]

In a similar way that a scalpel helps execute a surgery that's inoperable without a scalpel. There's a lot of difference between a scalpel and a 'robot' but its a tool nonetheless.

In other words, I agree with what you are saying.

[prasadjoglekar]

TL;DR: old human hand based surgery breaks the jaw to get to the area of the throat where the cancer was. Causes lots of complications after; or is simply deemed too hard.

The robot is more dextrous and thinner and can do the surgery without breaking the jawbones.

[glimshe]

Inoperable without the robot, which can reach deeper where hand controlled instruments wouldn't be able to.