That certainly sounds like a wart. Warts grow back, particularly if they're not removed completely.

You're not likely to start a cycle that prompts it to become cancerous (that's really a myth about moles, too, that messing with them can promote cancer; it can't. It's just that moles can become cancerous, whether they're messed with or not.). What you're at risk for is somehow injuring yourself or giving yourself an infection with self-conducted surgical excision. I'm fairly certain you're not using sterile procedure.

That wart-removal stuff they sell in bottle is salicylic acid, basically the liquid ingredient in aspirin. It gradually eats away the wart from the top down, and keeping it covered sometimes helps it go away and stay gone, at least according to what I just read at the Mayo Clinic site. If you've had that wart come back a few times even after you've excised the top, it's probably time to show it to someone with better removal ability and also let that professional send it to a pathology lab for evaluation. It's a quick, easy procedure to have a wart frozen off, and it's easy enough to do the next time you're in a clinic or doctor's office for something else. Mostly, though, you want to make sure you're not leaving yourself with an open wound on one of the dirtiest places there is, your hands, that could potentially be the entry point for a nasty bacterial infection.

Warts ΓΆβ?¬β?? Wart Removal and Treatment
They come back, by the way, because that's the genetic destiny of viruses. To return. Again and again.