Hi Zada,
If you google around, you'll find that some doctors (though not all) recommend getting a hysto at around the 5 years on T mark. I believe the mechanism for why it is beneficial or needed (for some) is due to the atrophy of the uterine muscles that occurs on a prolonged high dose of T. Some (but not all) trans guys get vaginal pain, cramping, irregular bleeding, dryness, and other symptoms after being on T for a few years. Hard to know the exact stats on how common it is, but definitely something to be aware of as a possibility.
Here's a little reading on it: