case_images: PMC9238209_01
case_images: A large tailgut cyst located from the perirenal to perivesical spaces in an 83-year-old female.. A. The size of the cystic mass is 30 cm in diameter at its longest point and it is located from the perirenal to the perivesical space on CT (arrow indicates the urinary bladder).. B. The renal pelvis is slightly dilated due to the compressed ureter by the cystic mass, but the urinary passage is patent on CT.. C. The urinary bladder (arrow) is compressed by the cystic mass and deviated to the left side on CT.. D. T2-weighted image shows a multiloculated cystic mass with multiple septations and an uneven thick wall.. E. Photomicrograph shows a thick-walled cyst with smooth muscle bundles and lymphoid cells (x 2; hematoxylin and eosin stain).. F. Photomicrograph shows the cyst, lined by a ciliated columnar epithelium (arrow) (x 100; hematoxylin and eosin stain).
case_images: jksr-83-168-g001.jpg
case_images: PMC9238209_01_jksr-83-168-g001.jpg
case_images: F1
case_images: A huge multiloculated 30.0 cm x 11.1 cm x 11.4 cm cystic mass was observed in the right perirenal space, retrorenal plane, posterior pararenal space, along the psoas muscle, and the pelvic extraperitoneal space (Fig. 1A). The renal pelvis was slightly dilated due to the ureter compressed by the cystic mass (Fig. 1B), and the urinary bladder was deviated to the left (Fig. 1C). T2-weighted images, and had a thick, uneven wall (Fig. 1D). There was no enhancing solid component or diffusion-restricted lesion. Therefore, this cystic mass mimicked a complicated cystic mass, such as a complicated lymphangioma. On microscopic pathology, a thick-walled cyst, smooth muscle bundle, and epithelial lining were observed (Fig. 1E, F).