Dr. Thorgeirsson joined the NCI in 1976 and has been the chief of the Laboratory of Experimental Carcinogenesis since 1981. He obtained his M.D. from University of Iceland of and Ph.D. from University of London.

His research interests are molecular pathogenesis of liver cancer and stem cell biology. Dr. Thorgeirsson has established a global leadership in the field of molecular carcinogenesis and genomic classification of liver cancer.

He has published close to 600 journal articles, book chapters, and books, and holds more than 7 patents. Dr. Thorgeirsson has received the NIH Merit Award and the Distinguished Scientific Achievement Award by the American Liver Foundation, serves as an Associate Editor for Hepatology and Cancer Science.

Dr. Thorgeirsson has been the NCI representative for basic science in the US/Japan Collaborative Cancer Research Program, elected member of the Icelandic and Hungarian Academy of Sciences, and the American Association for the Advancement of Science.