Dr. Johnson is a medical oncologist specializing in melanoma skin cancer. After receiving his MD from University of Alabama at Birmingham, he completed residency at Duke University followed by fellowship at Vanderbilt. He is also a graduate of the Master of Science in Clinical Investigation Program at Vanderbilt.

Dr. Johnson leads the melanoma clinical research program at Vanderbilt. His research interests cover a wide range of developing new immune and targeted therapies for melanoma, and in using existing treatments in the most effective ways. Specifically, he is exploring ways to profile cancers to predict which patients will benefit from immune therapies, and has published numerous papers in this area. He is also focused on understanding the effectiveness and toxicities of immune therapies in high risk patients, including those with autoimmune disorders, advanced age, or organ dysfunction. Dr. Johnson is the lead investigator on numerous clinical trials at Vanderbilt.