case_images: PMC10864140_01
case_images: A 77-year-old male with synchronous collecting duct carcinoma (pT1a) and papillary urothelial carcinoma (pT1) of the right kidney.. A. Initial CT urography reveals a lobulated mass with mild enhancement (arrows) in the right renal pelvis at the nephrographic phase. At the excretory phase, this lesion is shown as a lobulated contrast-filling defect. The mean density of the mass is 34 HU, 100 HU, and 78 HU in the pre-contrast, nephrographic, and excretory phases, respectively.. B. The mass located at the right renal pelvis shows invasion of the renal sinus fat and renal parenchyma (dashed arrows). Papillary mass in right renal pelvis is also noted (arrows).. C. Coronal CT image of the excretory phase shows the renal mass located at the right renal pelvis (arrow) with the renal sinus fat and renal parenchyma invasion (dashed arrow).. D. The resected gross specimen shows a grayish-white granular and papillary mass (arrow) in the renal pelvis. The tumor was composed of urothelial carcinoma in histological examination. Another grayish lobulated mass (dashed arrow) is located at the right kidney medullary region abutting the papillary mass. The lesion was confirmed as collecting duct carcinoma, histologically. In immunohistochemical examination, both tumors showed positive staining at CK and HMW-CK. However, CK20 staining was only positive in urothelial carcinoma (not shown).. E, F. Chest CT with lung window setting (E) and PET-CT (F) show lung and pelvic bone metastases (arrows) three months after surgery.. CK = cytokeratin, HMW-CK = high molecular weight cytokeratin, HU = Hounsfield units
case_images: jksr-85-222-g001.jpg
case_images: PMC10864140_01_jksr-85-222-g001.jpg
case_images: F1
case_images: On initial urography CT, an approximately 3.7 cm lobulated mass was detected in the right renal pelvis (Fig. 1A). The lesion had invaded the renal sinus fat and parenchyma (Fig. 1B, C). Histopathological examination revealed two different tumor types: CDC without lymphovascular invasion (pT1a) and papillary UC with subepithelial connective tissue invasion (pT1) without lymph node metastasis (Fig. 1D). A three-month follow-up CT scan after resection revealed multiple pulmonary and bone metastases (Fig. 1E, F).
case_images: PMC10864140_02
case_images: A 48-year-old male with synchronous papillary urothelial carcinoma and collecting duct carcinoma at the left kidney.. A. Initial abdominal CT reveals a 1 cm sized papillary lesion (arrows) in the left kidney upper calyx. This lesion shows mild contrast enhancement.. B. Another 3 cm-sized mass with an ill-defined margin (dashed arrows) is located at the medullary region of the left kidney. This lesion shows progressive enhancement. The mean density of the mass is 28 HU, 58 HU, and 74 HU in the pre-contrast, nephrographic, and excretory phases, respectively.. C. Contrast-enhanced CT shows multiple enlarged lymph nodes (arrows) with a central low density in the left renal hilar and para-aortic regions.. D. Gross section of the kidney shows a grayish papillary mass (arrow) in the upper calyx. In histological examination, the tumor was composed of urothelial carcinoma. Another white lobulated mass (dashed arrow) is located at the left kidney medullary region. The mass was confirmed as collecting duct carcinoma, histologically. The former lesion showed negative staining in high-molecular-weight cytokeratin and vimentin. However, the latter portion showed positive staining in high-molecular-weight cytokeratin and vimentin (not shown).. E. Two weeks after resection, chest CT with lung window setting shows multiple nodules in both lungs, compatible with pulmonary metastases.. HU = Hounsfield units
case_images: jksr-85-222-g002.jpg
case_images: PMC10864140_02_jksr-85-222-g002.jpg
case_images: F2
case_images: Initial abdominal CT with contrast enhancement revealed a 1.3 cm sized papillary mass with mild enhancement in the left upper calyx (Fig. 2A). Another 3 cm ill-defined mass with mild enhancement was detected in the medullary region of the left kidney (Fig. 2B). Multiple enlarged lymph nodes with necrotic portions were observed in the left renal hilar and para-aortic regions (Fig. 2C). A gross pathological examination revealed an intraluminal papillary mass in the upper calyx (Fig. 2D). Another mass was identified in the renal medullary region, demonstrating invasion into the renal sinus fat (Fig. 2D). CT with contrast enhancement for staging and further chemotherapy. Chest CT revealed multiple nodules in both lungs (Fig. 2E) and multiple heterogeneously enhanced lymph nodes in the left upper paratracheal, subcarinal, hilar, right middle lobar, interlobar, and segmental areas.