Dr. Thomas Sacks is a native of Washington, D.C., and attended public schools in the district through high school. After completing medical school at Tufts University, he completed medical internship and residency at Boston City Hospital. He then moved to the University of Minnesota Hospitals where he completed a two year fellowship in hematologic diseases. While there he received the outstanding research award for those engaged in post-graduate scientific studies. He then moved to the National Cancer Institute where he completed a three year oncologic fellowship.

Dr. Sacks has board certification in Internal Medicine, Hematology, and Oncology. He has maintained an active practice in all three fields, and has been engaged in the private practice of medicine in Washington since 1980. He is an Associate Clinical Professor of Medicine at both Georgetown and George Washington Universities. He has two children, and he and his wife reside in Bethesda.