PMC6358374_01
(A) Ultrasound showing a hybrid echo (cystic-solid) mass in the left kidney. (B) Ultrasound showing a hybrid echo (cystic-solid) mass in the right kidney. (C) Cross section of MRI showing a (cystic-solid) mass in the left kidney. (D) Cross section of MRI showing a (cystic-solid) mass in the right kidney. The coronal image is in the inset.
medi-98-e14236-g001.jpg
PMC6358374_01_medi-98-e14236-g001.jpg
F1
Both masses were hybrid echoed under ultrasound (Fig. 1A and B), indicating a cystic-solid structure with septa inside. MRI findings accord with the result of ultrasound, and the mass on the left kidney showed high signal inside (Fig. 1C and D), inferring hemorrhage or necrosis in the mass recently.
(A) Hematoxylin and eosin stain show tumor cells are separated by collagenous fiber (magnification x5). (B) Most area of the tumor showed tubular structure with mucus accumulated within (magnification x100). (C) "Hobnail" like cell lining at the end of the papillary (magnification x100). (D) Hematoxylin and eosin stain show papillary growth of the tumor in some area. (E) Hematoxylin and eosin stain show the tumor compressing and invading surrounding tissue (magnification x100). (F-J) Immunohistochemical staining for PAX8, GATA3, KSP, Ki67, CD10, successively (magnification x100).
medi-98-e14236-g002.jpg
PMC6358374_01_medi-98-e14236-g002.jpg
F2
Hematoxylin and eosin stain show that tumor cells are separated by collagenous fiber (Fig. 2A), in most area, the tumor cells form tubular structure with mucus accumulated within (Fig. 2B), in some area, the tumor cells form papillary structure (Fig. 2C) accompanied with typical high-grade "hobnail" like cells within the tubules. The tumor compressing and invading surrounding tissue is easy to be seen (Fig. 2D). TTF-1, OCT3/4, 34betaE12. The proliferation rate ki67 is about 20% (focally, Fig. 2I), PAX8 and GATA3 double positive supported the diagnosis (the antibodies employed are listed in Table 1).
PET-CT using 18F-FDG shows the postoperative residues and multiorgan and lymphonodes metastasis of the tumor 1 month after surgery.
medi-98-e14236-g004.jpg
PMC6358374_01_medi-98-e14236-g004.jpg
F3
Post-surgery PET-CT confirmed the mass on the left kidney is also a lesion of CDC, and suggested there were metastasis in lungs, bones and multiple sites of lymph nodes (Fig. 3).