山北 宜由¹, 河瀬 晴彦^{1, 2}, 村井 敏博^{1, 2}, 宮本 康二^{1, 2, 3}, 清水 幸雄^{1, 2, 4}, 梅崎 実^{1, 3, 4}, 池田 庸子^{1, 4}

Noriyoshi YAMAKITA¹, Haruhiko KAWASE^{1, 2}, Toshihiro MURAI^{1, 2}, Kouji MIYAMOTO^{1, 2, 3}, Yukio SHIMIZU^{1, 2, 4}, Minoru UMEZAKI^{1, 3, 4}, Tsuneko IKEDA^{1, 4}

¹松波総合病院内科, ²松波総合病院外科, ³松波総合病院放射線科, ⁴松波総合病院病理診断部

¹Department of Internal Medicine, Matsunami General Hospital, ²Department of Surgery, Matsunami General Hospital, ³Department of Radiology, Matsunami General Hospital, ⁴Department of Pathology, Matsunami General Hospital

キーワード : Adrenal incidentaloma, Intraperitoneal cyst, Ultrasonography, Ultrasound diagnosis, Ultrasound

A 57-year-old man with an intraperitoneal cyst was referred to this institution upon discovery of a left adrenal incidentaloma. The possibility of a functional adrenal tumor could not be ruled out endocrinologically. Ultrasonic examination showed a homogenous, solid supra-left renal tumor echo that had echogenicity similar to that of the spleen. The tumor measured 4.7 cm in diameter, and color flow imaging demonstrated no blood flow in it. Ultrasonic examination did not delineate a normal left adrenal; however, CT imaging and ¹³¹I-iodocholesterol scintigraphy suggested that the tumor originated extra-adrenally. Tumor intensity in MRI studies was lower than that of the liver in the T1-weighted image and slightly higher than that of the liver in the T2-weighted image. Laparoscopic surgery showed a round extra-adrenal cyst containing a white lardlike substance, and adhering tightly to the stomach and spleen. Formation of the cyst could conceivably be histopathologically attributable to degeneration of lipoma or encapsulation of fatty necrosis. The imaging findings of this cyst were not characteristic of a cyst. Extra care in obtaining images of tumors in the left adrenal region is necessary if the images are to shed light on tumor orign.