You've got healthy roots supporting that new growth. Hopefully the new growth is not rootstock and is worth having.

If it were mine, I'd let it grow and by fall you should have had blooms to tell if it is your yellow rose.

Unless it was a oncebloomer, you should see yellow blooms. If you don't, it is probably rootstock and will produce (if not pruned) deep red blooms next spring. The rootstock is probably Dr. Huey which is a deep red, not (to my nose) noticeably fragrant , once a year blooming climbing rose with a great ability to support a lot of Black Spot in eastern gardens.

What Ann said. The only way to be sure is to let it grow and see what happens.

I can usually tell if the shoots are root stock or the real rose. I have mostly Dr. Huey and the canes grow very tall and straight up and FAST and never get buds, except on the Dr. Huey's that I've left to grow from the past year.