Dr Horten is board certified in anatomic pathology, clinical pathology, and neuropathology. He earned his medical degree from Duke University. He completed his residency and fellowship in anatomic pathology at Cornell University Medical College-New York Hospital, his residency in neuropathology at Stanford Medical Center, and his residency in clinical pathology at the University of California, San Francisco School of Medicine. Dr Horten formerly served on the pathology staffs of Memorial Sloan-Kettering Cancer Center, the University of California San Francisco, and Lenox Hill Hospital. He has served as medical director of the New York laboratory since 1994. Dr Horten is actively involved in the development of the company’s oncology products and pathology services, and he lectures nationwide in support of these services. He has authored more than 35 publications in peer-reviewed journals in addition to several chapters in medical textbooks.