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Meet Our Physicians

Simeon Jaggernauth, M.D.

Scientist, Innovator, Medical Oncologist and former adjunct professor of Oklahoma State University Centers for Health Sciences, believes it’s absolutely important for patients to learn as much as they can about their illness.

Dr. Jaggernauth (aka Dr. Jag) earned his doctorate in medicine from Oklahoma State University Center for Health Sciences College of Medicine. He then completed an internship at OSU Medical Center, his internal medicine residency at the University of Oklahoma, and a subspecialty fellowship in Medical Oncology at the University of Louisville in Kentucky. Dr. Jag is an allopathic board certified Medical Oncologist and Internal Medicine physician by the American Board of Medical Specialties (ABMS). He is also board certified in Mechanical Engineering by the American Society of Mechanical Engineering (ASME). He worked in research and development prior to becoming a physician and co-invented several systems for water emulsion and solid particle detection counters for high pressure hydraulic systems used by Union Pacific Railroads® and NASA®. The co-invention of the Digital Moisture Alert® (dMA) and the Ferrous Contam Alert® (fCA) led to patents granted for both devices. U.S.Patent (#5,563,337). His Apps have been featured in the iTunes App Store® (iChemo Deluxe) for computing chemotherapy doses to help doctors with their chemotherapy dosing and to prevent medical errors in oncology.

Dr. Jag has served as principal investigator and sub investigator for multiple clinical trials on pharmaceutical agents used to treat metastatic breast, colon and lung cancers. He started the Medical Oncology Fellowship at Oklahoma State University and Cancer Treatment Centers of America. He was responsible for training doctors to become cancer fighters as Medical Oncologists. He served as the Chairman of the Cancer Committee a member of the Medical Executive Committee at CTCA. Prior to joining Landmark Cancer Center he was part of the MD Anderson Affiliated Network in Tulsa, Oklahoma. He also serves as a medical consultant on the scientific advisory board of several biotech companies including Genentech, General Electric Healthcare, Bristol-Myers Squibb, Celgene, and NovoCure. He is the Founder and Chairman of the non-profit organization, the H8 Cancer Foundation.

Dr. Jag has presented throughout the country as a speaker on new oncologic treatments available to patients. He has been published in the Journal of Clinical Oncology and Breast Cancer Wellness Magazine and has also been featured in Oklahoma Magazine, FOX, ESPN, Good Morning Texas on the Dallas ABC affiliate, and Kansas City Live. As an active leader of the community, Dr. Jag has been a guest speaker for the American Lung Association Lung Force, volunteered for the Tulsa Project Woman, and raced in the local Susan G. Komen Race for the Cure®. He was also featured in the Tulsa World with the debut of the Ken Burns film “The Emperor of All Maladies” when the PBS series aired nationwide. Dr. Jag loves spending time with his wife of over 25 years and their four children. He also enjoys playing video games with his kids, wake surfing, running, making movies with his drones, and high speed racing.

You can connect with him on Facebook by searching for @MyDoctorJAG or on Twitter @DoctorJAG.

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.

John D. Wells, M.D.

Dr. John Wells is a medical oncologist who specializes in the care of persons diagnosed with cancer: including lung cancer, breast cancer, mediastinal tumors, and cancer of unknown primary site. Research interests include tests for new anticancer treatments, the discovery of medicines that specifically attack lung cancer, multimodality therapy (using surgery, radiotherapy, and chemotherapy together to destroy cancers), and better ways to control physical symptoms caused by cancer and cancer treatment. Dr. Wells is particularly interested in finding ways to select the best treatments for persons with cancer based on clinical factors and the molecular characteristics of their tumor specimens.

Dr. Wells is Chief Medical Oncologist at Landmark Cancer Center in Rogers, Arkansas. Dr. Wells is a graduate of The University of Arkansas School of Medicine. Residencies included Tampa General Hospital, and The University of Arkansas Medical Center. Dr. Wells is board certified in Internal Medicine, Medical Oncology, Hematology, Internal Medicine, Advanced Achievement. Dr. Wells was listed among the Best Doctors in America, Central Region, Hematology and Medical Oncology, 1996 – 1997 and 2001 – 2002.

Dr. Wells clinical expertise includes: Lung Cancer; New Cancer Treatments; Thymoma; Mediastinal Tumors; Control of Side Effects and Physical Problems Caused by Cancer and Cancer Treatments.