Meet Joel L. Cohen, MD. J OEL L. COHEN, MD, is an internationally recognized expert on skin cancer and aesthetics. Dr. Cohen has been named a US News and World Report Top Dermatologist and has been voted by his peers as one of Denver's Top Doctors in 5280 magazine NINE times (including listings for cosmetic procedures and dermatology).. He is the director of AboutSkin Dermatology and ...Bill Pay‧Contact Us‧New Patient Forms‧About Us‧Michael E. Contreras, MD‧Photo Gallery.