My aunt had a Brunner's gland tumor removed a few months ago. The doctors actually couldn't confirm whether it was malignant or not. And a blockage of the intestine wasn't the concern either. They removed it because it was causing too many bad symptoms for my aunt. She had chronic pain, nausea, vomiting and diarrhea. She just couldn't take it anymore.
Thankfully, her surgery was successful and she is doing just fine. Her symptoms are gone. Of course, she was a little sore after surgery and needed to rest and take a few pain killers. But she's so happy that she had the tumor removed.
I think it might be a good idea to have these tumors removed even if they are benign and non-symptomatic because they might grow and turn malignant later on.