• Specialty: Radiation oncology
• Board-Certification: American Board of Radiology
• Fellowship: Massachusetts General Hospital 
• Residency: Harvard University
• Medical School: Quillen College of Medicine, East Tennessee State University 
• Hospitals: Johnson City Medical Center

Dr. Colvett serves as director of the Regional Cancer Center's radiation therapy program. He is assistant professor of surgery at Quillen College of Medicine.

Nathan Floyd, MD

• Specialty: Radiation oncology
• Board-Certification: American Board of Radiology
• Residency: Baylor College of Medicine
• Medical School: East Tennessee State University's Quillen College of Medicine
• Hospitals: Johnson City Medical Center, Indian Path Medical Center
• Memberships: American Radium Society, American Society for Radiation Oncology