CLINICAL HISTORY
The patient was a 43-year-old previously healthy female presented with fatigue and microhematuria. A CT scan of the left kidney showed a partially cystic mass with calcification, located in the middle pole cortex. The right kidney showed a simple cyst.
Left partial nephrectomy was performed.
LABORATORY DATA
Non-contributory.
ANCILLARY STUDIES
CT scan of the left kidney shows a partially cystic renal mass (Figure 1) with calcification (Figure 2).
GROSS PATHOLOGY
Left partial nephrectomy showed a well-circumscribed partially cystic mass, approaching the renal capsule.
The mass measured 1.7x1.5x1.2cm.
MICROSCOPIC PATHOLOGY
H&E stained sections show a biphasic cystic tumor, composed of epithelium and stroma. The epithelial component is composed of tubules with variable sizes, and the stomal component is composed of spindle cells (Figure 3).
No atypia or mitosis is observed in the tubular epithelium. The stroma resembles the ovarian stroma (Figure 4).
The cyst lining is composed of single layer of cells. The cells can be flattened, or with a hobnail appearance
(Figure 5 and 6).
IMMUNOHISTOCHEMISTRY
| EPITHELIUM |
|
STROMA |
| Keratin (+) (Figure 7) |
|
Vimentin (+) (Figure 9) |
| CK 7 (+) |
|
SMA (+) (Figure 10) |
| EMA (+) |
|
Desmin (focally +) |
| Ki-67 (up to 9%) (Figure 8) |
|
ER (+) (Figure 11) |
| Inhibin (-) |
|
PR (+) (Figure 12) |
| S100 (-) |
|
CD34 (+) |
| HMB45 (-) |
|
CD117 (focally +) |
| CEA (-) |
|
|
| Synaptophysin (-) |
|
|
| Serotonin (-) |
|
|
| |
|
|
|
