Dr. Shihabi received his medical degree from the Robert Wood Johnson School of Medicine in New Jersey, where he graduated as a member of the Alpha Omega Alpha Medical Honor Society and Robert Wood Johnson Alumni Scholar. He received his residency training in anatomic and clinical pathology at the University of California at San Francisco, where he also served as Chief Resident. He went on to complete a fellowship in surgical pathology at the University of California at San Francisco. He is board certified in anatomic pathology and clinical pathology.

Dr. Shihabi has worked as a staff pathologist at John Muir Medical Center, Concord Campus (formerly Mt. Diablo Medical Center), since 2003. In addition to his work in general anatomic and clinical pathology, he takes a special interest in hematopathology and gastrointestinal pathology, and oversees the hematology laboratory at the Concord campus. There, he has also served as Chair and President of the Department of Pathology. He is Medical Director of CoCoPath.