- Daniel F. Kelly, MD, Neurosurgery & BTC Director
- Chester F. Griffiths, MD; Head & Neck Surgery & Endoscopic Skull Base Surgery
- Pejman Cohan, MD, Endocrinology
- Omid Hamid, MD, Neuro-Oncology
- The Angeles Clinic & Santa Monica Hematology-Oncology Consultants – Medical Oncology
- Robert Wollman, MD & Lisa Chaiken, MD, Radiation Oncology
- Howard Krauss, MD, Neuro-Ophthalmology
- George P. Teitelbaum, MD, Interventional Neuroradiology
- Yuki Takasumi, MD & David Krasne, MD, Neuropathology

Dr. Daniel Kelly is a board certified neurosurgeon and Director of the Brain Tumor Center at Saint John’s Health Center. He is internationally recognized in the field of minimally invasive keyhole surgery for brain, pituitary and skull base tumors. He has one of the world’s largest series in endonasal surgery with over 1400 procedures performed including over 600 endonasal endoscopic surgeries, and over 1500 craniotomies for brain and skull base tumors. His current surgical practice encompasses the full spectrum of brain and skull base tumors, both benign and malignant, treated with minimally invasive and conventional approaches.

Dr. Kelly has authored or co-authored over 70 peer-reviewed publications and more than a dozen book chapters on topics of surgical outcomes and techniques, patient satisfaction and complication avoidance for a wide range of tumors including pituitary adenomas, meningiomas, craniopharyngiomas, Rathke’s cleft cysts, chordomas, sinonasal carcinomas and olfactory neuroblastomas. His research interests include endonasal endoscopic and keyhole surgical approaches, post-operative quality of life and pituitary hormonal dysfunction, as well as biomarkers of pituitary tumors and metastatic brain tumors. Dr. Kelly was the principal investigator of a National Institutes of Health funded study assessing pituitary hormonal loss after traumatic brain injury. He is currently the co-principal investigator of a study addressing the relationship between concussion, pituitary dysfunction and quality of life in retired professional football players. He is a member of the American Association of Neurological Surgeons, the Congress of Neurological Surgeons and the Pituitary Society and a member of the editorial board of the journal Neurosurgery. He is also active in fostering neurosurgical training programs in developing countries and is the Vice Chair of the Foundation for International Education in Neurological Surgery (FIENS).

Dr Kelly has a long-standing commitment to continuing medical education and patient education. Over the last decade he has organized 3 ongoing courses and symposia including the California Pituitary Conference, Endonasal and Keyhole Surgery Course (both for physicians), and the California Pituitary & Hormonal Health Symposium for patients and the public. He also lectures widely at national and international meetings and courses.

Dr. Kelly graduated from Claremont McKenna College in 1982 and from Georgetown University School of Medicine in 1986. He completed neurosurgical residency training in 1993 at George Washington University Medical Center and then joined the UCLA Division of Neurosurgery. In 1998 he became director of the UCLA Pituitary Tumor and Neuroendocrine Program. He was Professor of Neurosurgery and Vice-Chief of Clinical Affairs for the UCLA Division of Neurosurgery until 2007 when he joined the John Wayne Cancer Institute and Saint John’s Health Center. As Director of the Saint John’s Brain Tumor Center, Dr. Kelly continues to focus his efforts on advancing innovative treatments for patients with brain, pituitary and skull base tumors, providing fellowship training in minimally invasive neurosurgery, and patient education and support.

Chester F. Griffiths, MD; Head & Neck Surgery & Endoscopic Skull Base Surgery 

Dr. Griffiths is board certified in Otolaryngology, Head and Neck Surgery and Facial Plastic and Reconstructive Surgery. He has an extensive two-decade experience in endonasal endoscopic sinus surgery for sinonasal cancers, skull base tumors and pituitary tumors, and in the treatment of facial and nasal trauma, nasal bleeding, cosmetic deformities, sinus infections, and disorders of smell and taste. His practice also includes treatment of sleep apnea, snoring, difficulty breathing, tonsillitis, disorders of the larynx, thyroid tumors and other neck masses. As BTC Chief of Endoscopic Sinonasal & Skullbase Surgery, Dr Griffiths is co-surgeon with Dr. Kelly (BTC Director) in endonasal endoscopic pituitary and skull base surgeries and provides post-operative sinus care for patients undergoing endonasal endoscopic surgery. He is also a regular participant in our monthly BTC Case Conference, a faculty member in our annual BTC-sponsored Endonasal and Keyhole Surgery Course and actively participates in our neurosurgery fellowship training.

Dr. Griffiths completed a three year general surgery residency then a three Otolaryngology Head and Neck Surgery residency at Thomas Jefferson University Hospital. He then completed a visiting fellowship in Plastic and Reconstructive Surgery in Rio de Janeiro, Brazil with world-renowned plastic surgeon, Dr. Ivo Pitanguy. He began his professional career with his father Cadvan Owen Griffiths Jr., MD in 1989. He is currently Co-Director of Pacific Eye & Ear Specialists with Dr. Howard Krauss of Neuro-ophthalmology.

Dr. Griffiths has been active on the medical staffs of Saint John's Health Center and Santa Monica-UCLA Medical Centers for many years. He served as the Chairman of the Department of Surgery at Santa Monica-UCLA Medical Center for 10 years, stepping down in 2008 and Vice Chief of Staff for 3 years. He is an Assistant Clinical Professor at UCLA School of Medicine actively participating in the teaching of the family practice residents. He is a member of numerous societies and is a Fellow of the American Academy of Otolaryngology and the American College of Surgeons. He is a team physician for the Los Angeles Kings Hockey Team performing maxillofacial and plastic surgery for team members when needed. Dr. Griffiths volunteers at the Venice Family Clinic treating the uninsured both as a consultant and performing surgical procedures pro-bono. In recognition of his service, he received the Morton K. Rubenstein Award for Outstanding Volunteer Physician in 1995. He is currently on the Board of Directors of the Venice Family Clinic striving to continue the access for the uninsured to receive healthcare.

Pejman Cohan, MD, Endocrinology 

Dr. Cohan is a board certified endocrinologist and an expert in the diagnosis and treatment of patients with pituitary tumors and related hormonal disorders including functional pituitary tumors (acromegaly, Cushing’s disease, prolactinomas, TSH-secreting adenomas), non-functional pituitary adenomas, craniopharyngiomas and Rathke’s cleft cysts. He has extensive experience in the management of pituitary hormonal failure (hypopituitarism) after traumatic brain injury, radiotherapy and surgery and is an expert in diabetes and other metabolic disorders. He has a long academic track record in clinical endocrinology, including over 30 peer-reviewed publications on pituitary tumors and pituitary gland dysfunction, many of which were in collaboration with BTC Director, Daniel Kelly. Dr. Cohan is a frequent participant in our monthly BTC Case Conference, and a faculty member in our regular BTC-sponsored California Pituitary Conference and Endonasal and Keyhole Surgery Courses.

Dr Cohan completed his residency in internal medicine in 1998 at UCLA and completed a fellowship in Endocrinology, Diabetes and Metabolism in 2000 at UCLA. He joined the faculty at UCLA and was Co-Director of the UCLA Pituitary Tumor and Neuroendocrine Program until 2005 when he established his private practice in Beverly Hills at the Specialized Endocrine Care Center. He is currently an Assistant Clinical Professor of Medicine at UCLA School of Medicine and remains academically involved at UCLA and at the Saint John’s Brain Tumor Center.

Omid Hamid, MD, Neuro-Oncology 

Dr. Hamid is a board-certified medical oncologist with additional training in Neuro-Oncology. He has extensive experience in the comprehensive care of cancer patients including those with metastatic brain tumors and primary brain tumors including glioblastomas and astrocytomas. He has particular expertise in the care of patients with metastatic melanoma and has been a key investigator on numerous melanoma clinical trials. Dr. Hamid works closely with the BTC team in providing optimal care for patients with both primary and metastatic brain malignancies. He is a regular participant in our monthly BTC Case Conference and actively participates in fellowship training for the John Wayne Cancer Institute Surgical Oncology Fellows and the Neurosurgery Fellow.

Dr Hamid completed his residency in internal medicine at USC Medical Center in 2000 and completed his fellowship in Hematology/Oncology at USC Medical Center in 2005. He was the medical director of the Neuro-Oncology Clinic at USC/Norris Comprehensive Cancer Center from 2005-2006. He joined The Angeles Clinic and Research Institute in 2006. He is currently the Director of Neuro-Oncology, Chief of Clinical Research and Director of the Melanoma Center at the Angeles Clinic and Research Institute. Through his role as Chief of Clinical Research, Dr. Hamid oversees a program that ensures all types and stages of melanoma patients as well as patients with gliomas have the opportunity to benefit from the latest advances in therapy. Most recently, in his role with the Phase 1 Developmental Therapeutics Program, he has been instrumental in bringing new therapies from the investigational lab to the clinic for patient benefit. These treatments involve immunological modalities, therapies against tumor angiogenesis, and targeted agents that block internal processes in tumor cell's function, as well as vaccine trials for glioblastoma multiforme. Dr. Hamid is also an associate faculty member of the John Wayne Cancer Institute and a member of the American Society of Clinical Oncology and Society for Neuro-Oncology. He has over 20 peer-reviewed publications related to metastatic melanoma and other cancers.

Robert Wollman, MD, Radiation Oncology 

Dr. Robert Wollman is a board certified Radiation Oncologist and is Medical Director of Radiation Oncology at Saint John’s Health Center and a member of Valley Radiotherapy Associates Medical Group. He has extensive experience in radiotherapy for brain, pituitary and skull base tumors, as well as cancers of the head & neck, breast, bladder and prostate. In collaboration with Dr Lisa Chaiken of Radiation Oncology and Dr. Daniel Kelly, BTC Director, they treat patients with stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) using the new Saint John’s Varian Trilogy Linear Accelerator.

Dr Wollman graduated from the State University of New York at Binghamton with a Bachelor of Arts degree in Biology and he received his M.D. from New York University School of Medicine. His internship was spent at Columbia-Presbyterian Medical Center in New York and his residency was completed at Memorial Sloan-Kettering Cancer Center in New York where he served as Chief Resident in Radiation Oncology. He joined Valley Radiotherapy Associates Medical Group in 1994.

Dr. Wollman has written several articles on the hormonal regulation of breast cancer. He is a co-author of the Malignant Melanoma chapter of the Holland & Frei Cancer Medicine Volume 6 textbook. His interests include metastatic brain tumors, prostate cancer, intensity-modulated/conformal radiation therapy, partial breast irradiation radiation for skin cancer, and brachytherapy. He has lectured widely on treatment selection in prostate cancer. He is a regular participant in the Saint John’s BTC Case Conference and assists with our neurosurgery fellowship training.

Lisa Chaiken, MD, Radiation Oncology 

Dr. Lisa Chaiken is a board certified Radiation Oncologist at Saint John’s Health Center and a member of Valley Radiotherapy Associates Medical Group. She has extensive experience in radiotherapy for brain tumors as well as cancers of the head & neck, breast, bladder and prostate. In collaboration with Dr. Robert Wollman of Radiation Oncology and Dr. Daniel Kelly, BTC Director, they patients with stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) using the new Saint John’s Varian Trilogy Linear Accelerator.

Dr. Chaiken received her undergraduate degree, Phi Beta Kappa and Magna cum Laude, in History and Science from Harvard University. Her studies emphasized biological sciences, medical ethics, and historical factors influencing modern medicine. After receiving her medical degree from UCLA, she continued in the Department of Radiation Oncology, where she served as Chief Resident. After leaving UCLA, she still served as clinical faculty at the UCLA Breast Center for several years. She has been in practice over 15 years in the Santa Monica Community and joined Valley Radiotherapy Associates Medical Group in 2009.

Dr. Chaiken has been involved in many aspects of clinical treatment with special interests in breast, prostate, head and neck, brain and gynecologic cancer. Her work on Positron Emission Tomography (PET) imaging of radiation oncology patients with head and neck cancer received the Residents Essay Award from the American Society of Therapeutic Radiology and Oncology. Dr. Chaiken has been active in community and educational societies, serving on the Board of the Bay Surgical Society and currently the President of the Southern California Radiation Oncology Society. She has served on the Board of the American Cancer Society and the Women of Color Breast Cancer Support Group. She has experience in radiation safety as Chair of Radiation Safety Committees and as the Radiation Safety Officer at multiple hospitals. In recognition of her distinguished service and expertise, Dr. Chaiken was voted by her peers to be included in Best Doctors in America for over 15 years. Dr Chaiken is a regular participant in the Saint John’s BTC Case Conference and actively participates in our neurosurgery fellowship training as well as patient symposiums on the comprehensive treatment of brain, pituitary and skull base tumors.

Howard Krauss, MD, Neuro-Ophthalmology 

Dr. Krauss is a board certified ophthalmologist and fellowship trained neuro-ophthalmologist. He has extensive expertise in orbital and periorbital tumor surgery, strabismus surgery, LASIK, oculoplastic surgery and cosmetic surgery. As our BTC Neuro-ophthalmologist, Dr Krauss evaluates many of our patients pre- and post-operatively to assess their vision and eye movements. He is a regular participant in our monthly BTC Case Conference, a regular faculty member in our annual BTC-sponsored Endonasal and Keyhole Surgery Course and actively participates in our neurosurgery fellowship training.

Dr. Krauss had postgraduate training in Ophthalmology at the UCLA Jules Stein Eye Institute, Fellowship training in Neuro-ophthalmology and Orbital Surgery at the University of Pittsburgh and then a 2-year stint as Assistant Professor at the University of Texas Health Science Center, Southwestern Medical School, in Dallas, where he was Chief of Ophthalmology at Parkland Memorial Hospital, Chief of Neuro-ophthalmology, Oculoplastic Surgery and Strabismus and Director of the Residency Training Program. He began private practice in Ophthalmology and Ophthalmic Surgery in 1984. He is currently Co-Director of Pacific Eye & Ear Specialists, with Dr. Chester Griffiths.

In addition to his private practice and collaboration with the BTC, Dr. Krauss is Clinical Professor of Ophthalmology and Neurosurgery at UCLA, where he is also Co-director of the UCLA Skull Base Surgery and Orbitocranial Tumor Programs, Associate Member of the Jules Stein Eye Institute (JSEI) Division of Neuro-ophthalmology and Member of the UCLA Pituitary Tumor Program and of the JSEI Optic Neuropathy and Orbital Disease Centers. Dr. Krauss has lectured locally, nationally and worldwide, and has directed two International Congresses of Ophthalmology in Santiago, Chile. He is a recognized expert in his field, has published numerous papers and book chapters and has served as a Reviewer for numerous peer-reviewed journals. Dr. Krauss, and his associate, Dr. Chester F. Griffiths, were the first in the world to devise, carry out, present and teach the advanced surgical technique of Transnasal Endoscopic Image-Guided Orbital Surgery.

Dr. Krauss has been an active participant in medical and professional organizations and endeavors. He has been a Member of the Boards of Directors of the North American Skull Base Society, the UCLA Medical Faculty Group, the Jules Stein Eye Care Network, the California Academy of Eye Physicians & Surgeons, the Los Angeles County Medical Association, the California Ambulatory Surgery Association, the Center for the Partially Sighted, the California Medical Association Political Action Committee, the California Medical Association and a member of the Institute Advisory Council of the Alfred E. Mann Institute for Biomedical Engineering at USC. He has served as President of the UCLA Department of Ophthalmology Association, the California Academy of Eye Physicians and Surgeons and the Los Angeles County Medical Association. He is also a Special Examiner and Mentor Examiner of the American Board of Ophthalmology, a Delegate to the California Medical Association (CMA) and Chair of the CMA Technical Advisory Committee on Healthcare Reform.

George P. Teitelbaum, MD, Interventional Neuro-radiology 

Dr. Teitelbaum is a board-certified radiologist and interventional neuroradiologist. He has extensive experience in endovascular treatment of cerebral aneurysms, arteriovenous malformations (AVMs), carotid stenosis, stroke and pre-operative brain tumor embolizations, as well as performing diagnostic cerebral angiograms and venograms including petrosal sinus sampling for evaluation of Cushing’s disease.

Dr. Teitelbaum received his medical degree from the University of California, San Diego School of Medicine. He completed his surgical internship at the University of California, San Diego Medical Center, his radiology residency at the University of California, Irvine, and his fellowship in interventional neuroradiology at the University of California, San Francisco Medical Center in 1994. He also completed a fellowship in magnetic resonance imaging at Huntington Medical Research Institutes and a fellowship in interventional radiology at The George Washington University Hospital. Dr. Teitelbaum was the director of interventional neuroradiology in the Department of Neurological Surgery for 15 years and professor of neurological surgery at the University of Southern California/Keck School of Medicine. He currently serves as the medical director of the Providence Neurovascular Center and is a member of the Providence Holy Cross and Providence Saint Joseph Medical Staffs, as well as Children’s Hospital Los Angeles, providing care in adult and pediatric interventional neuroradiology.

Dr. Teitelbaum has an extensive academic track record in interventional neuroradiology with over 100 peer-reviewed publications. He has been instrumental in advancing the field in new technology for endovascular treatment of aneurysms, AVMs and stroke.

Yuki Takasumi, MD, Neuropathology 

Dr. Takasumi has been on the staff at Saint John’s Health Center since 2000. She completed medical school at Tufts University in 1995, her residency in anatomic and clinical pathology at the University of California, Los Angeles in 1999, and a surgical and tumor pathology fellowship at the University of Southern California in 2000. With subspecialty interest in neuropathology and skull base tumors, she undertook additional specialized neuropathology training at UCLA in 2007 and has headed the Neuropathology Section in the Pathology Department at Saint John’s since then. Dr. Takasumi is a regular participant in our monthly BTC Case Conference, and actively participates in our neurosurgery fellowship training.

David Krasne, MD, Pathology 

Dr. Krasne joined the staff at Saint John’s in 1990 and became the Medical Director of the Pathology Department and Clinical Laboratory in 1994. Under Dr. Krasne’s leadership the pathology group at Saint John’s supports the Health Center and its ever growing cancer program by providing state-of-the-art laboratory diagnostic services. Dr. Krasne and his team have contributed over 75 publications to the medical literature working closely with physicians and researchers at the John Wayne Cancer Institute. Some of their most notable pioneering work with Drs. Donald Morton and Armando Giuliano helped catapult sentinel lymph node surgery into everyday surgical practice world-wide. Dr. Krasne’s post-graduate background at Stanford University was in anatomic pathology where he specialized in general tumor pathology. Later he studied laboratory medicine at the University of Southern California, and obtained special expertise in fine needle aspiration cytology, a minimally-to-non-invasive technique of sampling tumors, at the Karolinska Institute in Stockholm, Sweden. Dr. Krasne is a regular participant in our monthly BTC Case Conference and actively participates in our neurosurgery fellowship training.