cases, retroperitoneum Week 395: Case 1 April 26, 2023 pathadmin 1. Presented by Peter Illei, M.D. and prepared by Andrea Subhawong, M.D.2 year old boy with a large abdominal/retroperitoneal mass. Immunostains were positive for chromogranin and synaptophysin. Cytokeratin was negative.images/6.1.09.01a.jpgimages/6.1.09.01b.jpgimages/6.1.09.01c.jpgNeuroblastoma, undifferentiatedWilms tumorDesmoplastic small round cell tumorPNET Loading...