AbstractDuring the past 5 years, three patients with adenocarcinoma of the urachus were treated at our hospital. Abdominal ultrasonography helped clinch the diagnosis in all cases. All patients underwent surgical excision of the neoplasm with partial cystectomy. The clinical, radiological, and histological findings, as well as the pathogenesis of this rare neoplasm are discussed along with the surgical management. © 1992 Wiley‐Liss, Inc.