Tampa General Hospital teams are monitoring the storm and preparing for Hurricane Ian. Click here for the latest updates for our patients and community. See the Latest Updates

Neuro-Oncology Team

As an academic medical center, Tampa General Hospital offers a collaborative approach to all patient care with experts representing multiple specialties. Our multidisciplinary team includes neuro-oncology specialists, neurosurgeons, radiation oncologists, pathologists, psychologists, physicians assistants, nurses, an integrative medicine team, nutritionists, social workers and more. Additionally, Patients work directly with a care navigator to answer any questions they may have and ensure their experience is as seamless as possible.

Neuro-Oncology Specialists

Dr. Tulika Ranjan headshot   

Tulika Ranjan, MD
Director, Neuro-Oncology
TGH Cancer Institute

Dr. Tulika Ranjan is a renowned neuro-oncologist with training and experience from the best comprehensive neuro-oncology programs in the world. She has a wealth of experience in treating adult primary brain and spinal cord tumors and has conducted groundbreaking research on new therapies for treating glioblastoma (GBM).

Prior to joining Tampa General Hospital, Dr. Ranjan was the director of the Allegheny Health Network (AHN) adult neuro-oncology program that specialized in advanced modalities such as laser interstitial thermal therapy and cancer stem cell chemo-sensitivity testing. She also served as chairperson for AHN Cancer Institute Neurologic-Oncology disease site leadership team.


Noman Ashraf, MD

Dr. Noman Ashraf is a hematologist-oncologist with Tampa General Hospital who specializes in solid tumor oncology. He has been an associate professor of medicine in the Division of Hematology and Medical Oncology at the USF Health Morsani College of Medicine since 2019.

Dr. Ashraf has been an invited speaker and presenter at several regional, national and international conferences, and has served as principal investigator for clinical trials and is credited with several peer-reviewed publications, book chapters and presentations on his areas of expertise.

Neurosurgery Specialists

Headshot of Harry Van Loveren

Harry van Loveren, MD
Medical Director, Neurosurgery, TGH Neuroscience Institute
Professor & Chair, Department of Neurosurgery and Brain Repair, USF Health Morsani College of Medicine


Siviero Agazzi, MD, MBA, FACS
Chair, Pituitary Clinic


Kunal Vakharia, MD
Neurosurgeon, Neuro-oncology


Puya Alikhani, MD, FAANS
Neurosurgeon, Neuro-oncology

Radiation Oncology Specialists

Dr John David Headshot

John David, MD
Director of Brachytherapy Services, Tampa General Hospital

Dr. John David is a board-certified radiation oncologist with Tampa General Hospital. He serves as the Director of Brachytherapy Services and Lead Physician of Radiopharmaceuticals. He has advanced sub-specialized training in brachytherapy and extensive expert training in radiopharmaceuticals. His other interests include stereotactic radiosurgery (SRS), intensity modulated radiation therapy (IMRT) and stereotactic body radiation therapy/stereotactic ablative radiation therapy (SBRT/SABR). Prior to joining Tampa General Hospital, Dr. David was fortunate to visit and work with physicians at the New York Proton Center, gaining experience in one of the most contemporary radiation treatment modalities – proton therapy.

 Doctor Brian Collins Headshot

Brian Collins, MD, FCCP
Radiation Oncologist, TGH Cancer Institute

Dr. Brian T. Collins is a board-certified radiation oncologist with significant clinical experience in treating brain, breast and lung cancers. Regarded as a world-renowned expert in CyberKnife® radiotherapy technology, Dr. Collins specializes in cutting-edge radiation oncology techniques and tools. Dr. Collins has frequently contributed to scientific journals, books and publications in areas of his expertise. He is a Fellow in the American College of Chest Physicians (ACCP) and a member of numerous related professional organizations.