Prof Stahl graduated from the Julius-Maximilians-University in Würzburg in 1986 and specialised in Internal Medicine in 1994. In 2007 he qualified as professor of Internal Medicine at the University of Essen. Prof Stahl carried out his Internal Medicine training at the Medical University Hospital in Würzburg, the Hannover Medical School, the St. Jude´s Children Research Hospital in Memphis, USA and the West German Cancer Centre in Essen. From 1996 to September 2010 Prof Stahl was chief physician of the Department of Medical Oncology and Hematology. Since 2010 Prof Stahl is director of the Department of Medical Oncology, Kliniken Essen-Mitte, Essen, Germany.

Prof Stahl is a member of several national and international societies and belongs to the leading group of the Section esophageal / gastric carcinoma of the Association of Medical Oncology and to the interdisciplinary working group of the German Cancer Society. He is the author of several works in the diagnosis and treatment of tumours of the digestive tract. For his research in the field of esophageal cancer in 2005 he was awarded the Science Prize of the Association of Medical Oncology of the German Cancer Society and in 2008 the "German Cancer Award". Prof Stahl is responsible for the guidelines of the European Society for Cancer Diagnosis and Therapy of Esophageal Carcinoma.

Prof Stahl has clinical trials experience as sub-investigator in numerous trials I-III phase since 1988, in gastric cancer, colorectal cancer, lung cancer, renal cancer, breast cancer, CUP. He was principal investigator of large multicenter German or International phase III trials in oesophageal and oesophago-gastric cancer in 1994, 2000 and 2010.