Dr Kümmel is the Clinical Director and Chairman of the Interdisciplinary Breast Unit Clinics of Essen-Mitte in Germany, where he is also Lead of the Breast Cancer Research Programme.

In addition to his work at the Essen-Mitte clinics, Dr Kümmel is an Executive Board Member of the Gynaecological Oncology Working Group (AGO) and a Scientific Director of the West German Study Group (WSG), an academic study group for breast cancer. He qualified as an Extraordinary Professor at the medical school of Humboldt University Berlin, Germany.

Dr Kümmel is a faculty member of ESMO for breast cancer and a member of the ESMO Scientific Committee.

Reflecting his commitment to breast cancer surgery, Dr Kümmel is a member of both the Scientific Board of Oncoplastic Breast Surgery (OPBC) and the scientific committee of national and international symposia in breast cancer and surgical oncology.

In addition to his role as an Executive Board member of the AGO, he is also a speaker for its Commission for Integrative Medicine (AGIMed) a member of its organ commission (AGO Mamma). 

Dr Kümmel is a member of the Scientific Committee of the Northeast German Society of Gynaecological Oncology (NOGGO), a breast cancer group.

As head of clinical investigations and trials at the Essen-Mitte clinics, Dr Kümmel is a global Principal Investigator. He has been Chief Investigator for 33 national and international Phase 1–3 clinical studies, Principal Investigator for 85 Phase 1b–3 clinical studies. He has also served as sub investigator for 34 Phase 2–3 clinical studies.

As a member of the Independent Data Monitoring Committee (IDMC), Dr Kümmel is participant in several national and international steering committees, including involvement in the Steering Committee, protocol group, or IDMC of 44 national and international Phase 1–3 clinical trials.

Dr Kümmel has published extensively on breast cancer surgery and treatment and has co-authored over 230 publications and almost 60 books and chapters. As a renowned speaker, Dr Kummel has presented over 250 congress abstracts and proceedings and given more than 850 presentations and lectures.

Dr Kümmel qualified as a doctor from Humboldt University Berlin in 1997 and gained a PhD from University Hospital Essen in 2008. Since 2018, he has been Extraordinary Professor of the Medical School of University Hospital Charité at Humboldt University Berlin, Germany.