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Meet Our Physicians

Timothy D. Nichols, M.D.

Dr. Timothy Nichols has extensive experience with external beam radiation (IMRT, IGRT, 3D Conformal), and he specializes in Stereotactic Radiosurgery and Partial Breast Irradiation. Dr. Nichols is Board Certified in the field of Radiation Oncology by the American College of Radiology. A Dallas resident, Dr. Nichols earned his undergraduate and medical degrees from the University of Maryland in Baltimore, Maryland.

Dr. Nichols served his residency in Radiation Oncology at the University of Maryland Medical Center, as well as receiving a Fellowship from that institution. He has most recently served as Radiation Oncologist at the Presbyterian Hospital of Dallas, and earlier held the position of Medical Director at the Plano Oncology Center. He is a member of the American Society for Therapeutic Radiology and Oncology, the American College of Radiology, the American Medical Association, the Texas Medical Association and the Dallas County Medical Society.

Wilhelm Lubbe, M.D., Ph.D.

Radiation oncology is undergoing an explosion of new cutting edges techniques.  Recently spending four years at the Fox Chase Cancer Center in Philadelphia, Dr. Wilhelm Lubbe worked at a unique cancer only institution holding two Nobel Prize winners.  At this world leading cancer treatment center, Dr. Lubbe has utilized some of the world’s most innovative emerging techniques. A Diplomat of the American Board of Radiology, Dr. Lubbe is a Board Certified Radiation Oncologist.  This experience affords Dr. Lubbe the luxury of knowing the full extent of the advantages and limitations of each new technology and technique.

Holding two doctoral degrees, Dr. Lubbe was awarded a prestigious medical program where he received both a M.D. and Ph.D. at the same time.  This was within a special program through Jefferson Medical College in Philadelphia.  In addition to his clinical expertise, he obtained a Ph.D. in molecular cancer research.  Beyond winning multiple awards in both medicine and cancer research, he has coauthored a United States patent for a molecular guided cancer therapy. This strategy activates the body’s own internal and environmental bio-mechanisms to inhibit cancer spread.  His research on natural molecular cancer treatments and innovative radiation techniques have been presented at oncology meetings drawing a world wide audience.

Outside of work, Wilhelm enjoys a great variety of activities in the Dallas area.  Of note, he was a NCAA Division I tennis player at Villanova University and received All-Conference distinctions as a pre-medical student athlete. Surprisingly, after medical school Wilhelm also became a nationally ranked USA Track and Field sprinter.  Born in West Virginia, Wilhelm Johannes Lubbe has a completely German name with a South African twist.  Lubbe, like Porsche, ends in an “e” but sounds like an “a”.  In Texas, Wil says Lubbe is pronounced like Bubba with an “L”.

Joshua Garren, M.D.

Joshua Garren, MD., Chief Radiation Oncologist at Landmark, is an award winning, board-certified radiation oncologist, from the world-renowned Lahey Clinic in Boston where he led the radiosurgery program for over eight years.

His research career began in the Brown University MD/PhD program. His research on minimizing the side effects of radiation has been presented and supported internationally. He received his neurosurgery training at NYU Medical Center, where he worked on the first radiosurgery system in New York. Dr. Garren’s interest in health care for the disadvantaged began at the Harvard/Brown MD/MPH program. He has worked with Doctors of the World and has received a fellowship from the Albert Schweitzer Foundation.

Dr. Garren has been voted one of Boston’s top doctors by his peers in each of the past four years. Prior to joining Landmark, Dr. Garren was named to the first US News and World Report list of top doctors in the United States.

Dr. Garren speaks English, French and Russian. During his free time, he coaches his five budding young soccer stars, Daniel, Ariella, Maya, Jonathan and Shira Garren.