- 1971 B.A. Saint Olaf College
- 1975 M.D. University of Iowa
- 1975-78 Pediatrics Residency, Upstate Medical Center, New York
- 1980-83 Radiology Residency, Yale New Haven Hospital, Connecticut
- 1983-85 Pediatric Radiology Fellowship, Children's Hospital, Boston, Harvard Medical School
Dr. Hoffer is academically active in oncoradiology and interventional oncology nationally participating in Quality Assurance Research Center (QARC), Children's Oncology Group (COG), American College of Radiology Imaging Network (ACRIN) and Strokes with Transfusion Changing to Hydroxyurea (SWiTCH).