Can having a 2.3 cm rich adrenal adenoma become cancerous down the line? Should I have it removed before anything cancer happens?

Adrenal. adenomas usually do not become malignant but may very well be implicated in other problems including a number of endocrine (glandular) disorders. Follow the advice of your treating physician. A referral to a Board Certified Endocrinologist may be indicated!

Hope this is helpful
Dr Z.
Possibly but reality. no one knows. Medicine is low-tech, humans Hi-Tech: http://goo.gl/Blh6rW. Consider: https://emedicine.staging.medscape.com/article/116587-guidelines for an overview of some of current "standard of care" suggested "guidelines" Always remember that no-one has your best interests at heart more than you do. Others are only advisers selling what they choose to sell, they do not live with your outcomes.