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James Thompson, M.D., Ph.D., Medical Director

Dr. Thompson is a practicing surgical and hematopathologist who is board certified in anatomic pathology. Dr. Thompson’s previous experience includes faculty positions at UC Irvine Medical School, Medical and Laboratory Director of Meyer Pharmaceuticals, Medical Director/Vice President of Technology Development at Impath, Medical Director of Oncotech, President and Medical Director of Pathogenesys, Medical Director of US LABS, Medical Director of Ambry Genetics, and Director of Hematopathology at Genoptix. Dr. Thompson obtained his undergraduate degree from University of California Irvine with his medical degree and doctorate in Microbiology and Molecular Genetics from University of California Irvine School of Medicine. He completed his pathology residency at the Stanford, with additional fellowship training in molecular pathology at Stanford and hematopathology at University of California Schools of Medicine.

Joanna Askren, M.D., Pathologist

Dr. Askren is a practicing pathologist who is board certified in forensic, anatomic, and clinical pathology. Dr. Askren’s previous experience includes being a Forensic Pathologist for the Riverside County Sheriff’s Department. Dr. Young received her undergraduate degree in Biomedical Sciences from the University of California, Riverside. She graduated from the biomedical sciences program with an M.D. degree from UCLA. She did a year of family medicine internship at Kaiser Permanente in Fontana. She completed her pathology residency at USC and her forensic pathology fellowship at the Los Angeles Department of Coroner. After leaving forensic pathology, she completed a surgical pathology fellowship at Olive View – UCLA Medical Center.

Ruben Gamez, M.D., Pathologist

Dr. Gamez is board certified in hematopathology, anatomic and clinical pathology. Dr. Gamez’s previous experience includes Staff Hematopathologist and Assistant Laboratory Director for Plus Diagnostics, Staff Hematopathologist and Co-Laboratory Director at Specialty Laboratories, and Staff Pathologist at Georgetown University Hospital. Dr. Gamez obtained both his undergraduate degree and M.D. from the University of Arizona. He completed his pathology residency at the St. Joseph’s Hospital (Phoenix, AZ), with additional fellowship training in hematopathology at Georgetown University Hospital and a Donald West King fellowship at the Armed Forces Institute of Pathology (AFIP) in pulmonary pathology. Dr. Gamez also performed a rotation in lymph node pathology at the National Institute of Health /National Cancer Institute (NIH/NCI) under Dr. Elaine Jaffe.

Alfred Garcia, M.D., Pathologist

Dr. Garcia is board certified in anatomic and clinical pathology. Prior to joining Mosaic, Dr. Garcia has worked as a Pathologist at BioPath Medical Group/Fountain Valley Regional Hospital, Foothill Regional Medical Center, Thousand Oaks Pathology Associates Diagnostics/Los Robles Medical Center, and the Alzheimer’s Disease Research Center at USC. Dr. Garcia obtained his undergraduate degree in Biological Sciences at UC Irvine, and his Medical Degree at USC’s Keck School of Medicine. He completed his anatomic and clinical pathology residency training and fellowships in surgical pathology and cytopathology at LA County/USC Medical Center.

TuDung Nguyen, M.D., Ph.D., Pathologist

Dr. Nguyen is a practicing anatomic pathologist, hematopathologist and molecular pathologist who is board certified in anatomic pathology, hematopathology and molecular pathology.  She received her B.S. at UC Irvine and completed a combined M.D./Ph.D. program at the USC Keck School of Medicine where she obtained her medical degree and doctorate in Biochemistry/Molecular Biology. She completed residency in Anatomic Pathology and fellowships in Surgical Pathology, Hematopathology and Molecular Genetic Pathology at Stanford University. She previously worked as a faculty member at Washington University School of Medicine where she also served as the Associate Director of the fluorescence in situ hybridization (FISH) laboratory and Program Director of the Hematopathology Fellowship; a Hematopathologist at Genzyme Genetics and CSI Laboratories; and the Medical Director of Cancer Genetics Inc. and Oncogene Diagnostics. She has 25+ years of cancer research experience and has published over 40 peer-reviewed papers plus book chapters on the topics of molecular pathology and cytogenetic FISH technologies.

Rana Richeh, M.D., Pathologist

Dr. Richeh is a practicing pathologist and is board-certified in anatomic and clinical pathology. Prior to joining Mosaic Laboratories, Dr. Richeh served as a pathologist at Diamond Reference Lab. Dr. Richeh received her Medical Degree from Damascus University School of Medicine and completed residency and fellowship at Cedar Sinai Medical Center in Los Angeles, California. Dr. Richeh is a member of USCAP and ASCP.