吉田 寛¹, 江上 格¹, 谷口 善郎¹, 平岡 保紀², 前田 昭太郎³, 恩田 昌彦⁴

Hiroshi YOSHIDA¹, Kaku EGAMI¹, Yoshiroh TANIGUCHI¹, Yasunori HIRAOKA², Shotaroh MAEDA ³, Masahiko ONDA⁴

¹日本医科大学付属多摩永山病院外科, ²日本医科大学付属多摩永山病院泌尿器科, ³日本医科大学付属多摩永山病院病理部, ⁴日本医科大学付属病院第1外科

¹Department of Surgery, Tamanagayama Hospital , ²Department of Urology, Tamanagayama Hospital , ³Department of Pathology, Tamanagayama Hospital , ⁴First Department of Surgery, Nippon Medical School

キーワード : Aspiration biopsy, Ultrasonography, Urachal carcinoma

We describe a case of urachal carcinoma, a rare neoplasm with a poor prognosis, that was accurately diagnosed by aspiration biopsy under ultrasonography. Physical examination disclosed a mildly tender mass in the lower abdomen of a 26-year-old man with lower abdominal pain. Laboratory studies showed elevation of white blood cell count (WBC, 15 100) and CEA (10.0 ng/ml). Microscopic urine analysis was normal. Ultrasonography revealed a 5×5 cm hypoechoic mass with a central hyperechoic lesion. Aspiration biopsy under ultrasonography indicated that the mass was a mucinous adenocarcinoma, class V. Wide resction of the urachal tumor with resection of the umbilicus, musculus rectus abdominis, fascia, peritoneum, the superior part of the bladder, and pelvic lymph nodes was performed. The pathology report described the mass as a mucinous adenocarcinoma without invasion to the urinary bladder or umbilicus, confirming the diagnosis based on aspiration biopsy under ultrasonography. We thus conclude that aspiration biopsy under ultrasonography may be useful in the diagnosis of urachal carcionoma.