Meet Our Physicians

Medical Oncology Services

When it comes to your cancer treatment, Florida Hospital East Orlando relies on the expertise of health care professionals who work hard to make sure you or your loved one is treated with quality skill and compassionate care. A Medical Oncologist is a doctor with a specialty in treating cancer using medication such as chemotherapy, hormones and analgesics. For each treatment option, they will discuss with you the length, the effectiveness according to data from clinical trials and potential side effects.

Dr. Castillo graduated from the University of Puerto Rico where he earned his medical degree. He then went on to become a clinical research fellow in internal medicine/oncology at Thomas Jefferson University Hospital in Philadelphia. He is board certified in medical oncology and is bilingual.  Dr. Castillo has been practicing in Central Florida for more than 20 years. He routinely speaks to the Hispanic medical doctors at the annual Pan-Am meeting. 

Sarah George, MD
Hematology and Oncology

Dr. George graduated from Wayne State University School of Medicine in Detroit, Michigan with her Doctor of Medicine.  She completed her Internal Medicine Residency at William Beaumont Hospital, Royal Oak, MI and her Hematology/Oncology Fellowships at University of Chicago in Chicago, IL.  Dr. George is Board Certified in Oncology, Internal Medicine and Hematology.  She is a member of the American Society of Clinical Oncology and the American  Society of Hematology.

Tarek Mekhail, MD, MSc, FRCSI, FRCSEd 
Lung and Thoracic

Dr. Mekhail joined the team from the Cleveland Clinic where he was the director of the Lung Cancer Medical Oncology Program. He is currently the medical director of the Thoracic Oncology Program at the   Florida Hospital Cancer Institute. He also is an associate professor at the University of Central Florida. Dr. Mekhail completed his medical degree at Cairo University in 1984. He then completed his medical training in the United Kingdom, where he earned fellowships of the Royal College of Surgeon of Edinburgh and Ireland. He completed his medical oncology fellowship at the Cleveland Clinic in Cleveland, Ohio. He has been voted one of the Best Doctors in America in 2007-2008, 2008-2009, and 2009-2010. Dr. Mekhail's extensive experience and leadership in the field of lung cancer are assets to our community.

Ahmed Zakari, MD
Gastrointestinal and Lymphoma

Dr. Zakari earned his M.D. from the University of King Mohammed V in Rabat, Morocco. He began his career in basic science research at Georgetown University, where he also taught. He completed training in hematology and oncology at Georgetown University Hospital's Lombardi Cancer Center. He is board certified in internal medicine and medical oncology. Working with one of the world pioneers in colon cancer at Georgetown University led to his interest in gastrointestinal/colon cancers. He also has interests in lymphoma. He is the director of GI cancers at the Florida Hospital Cancer Institute. He is also chairing the Division of Hematology in the Department of Internal Medicine at Florida Hospital. He speaks fluent Arabic and French.