John Floberg

Biography

Dr. Floberg is an Associate Professor in the Department of Radiation Medicine at the University of Wisconsin. Originally from Minneapolis, he completed both his MD and PhD at the University of Wisconsin before pursuing residency training in radiation oncology at Washington University in St. Louis.

Clinically, Dr. Floberg specializes in the treatment of genitourinary cancers. As a radiation oncologist, he collaborates closely with urologists, medical oncologists, radiologists, pathologists, and other specialists to provide comprehensive, patient‑centered care. He is proud to practice at a cancer center that offers state‑of‑the‑art treatments for patients with genitourinary malignancies, including high‑dose‑rate prostate brachytherapy, stereotactic body radiation therapy (SBRT), MRI‑guided radiation therapy, and targeted radiopharmaceutical therapies such as Radium‑223 (Xofigo) for metastatic prostate cancer. He is also actively involved in medical education, teaching residents and medical students in the clinic and guiding their training in these advanced techniques.

Dr. Floberg has been deeply involved in advancing theranostics at the University of Wisconsin. He played a key role in establishing a multidisciplinary theranostics program within the Division of Nuclear Medicine, including the development of a clinical theranostics dosimetry program that supports personalized radiopharmaceutical therapy. He also serves on the executive committee for the UW Carbone Cancer Center’s Initiative for Theranostics and Particle Therapy, helping lead the initiative’s educational mission.

His research centers on advanced imaging modalities—such as PET and MRI—and their application in prostate cancer. With the rapid expansion of imaging technologies in recent years, his work focuses on how these tools can reveal important biological features of tumors, guide individualized treatment approaches, and support the development of new therapeutic strategies. He is committed to mentoring students in his research program, fostering their growth as independent scientists and clinicians.

In addition to his imaging and theranostics research, Dr. Floberg is actively engaged in clinical trials. He has been one of the Carbone Cancer Center’s top‑accruing investigators, serves as the national principal investigator for a Phase II clinical trial through the NCI’s Experimental Therapeutics Clinical Trials Network, and contributes nationally through his work with the ECOG/ACRIN and NRG cooperative groups.