Robert D Tunks1, Jozef Malysz2, Joseph B Clark2. 1. From Departments of Pediatrics (R.D.T., J.B.C.), Pathology (J.M.), and Surgery (J.B.C.), The Pennsylvania State University College of Medicine, Hershey. rtunks@hmc.psu.edu. 2. From Departments of Pediatrics (R.D.T., J.B.C.), Pathology (J.M.), and Surgery (J.B.C.), The Pennsylvania State University College of Medicine, Hershey.