Presentation
Patient with sickle cell trait presenting with abdominal pain.
Patient Data
The small bowel is dilated from left upper to right lower quadrants, consistent with a small obstruction. At the right kidney upper pole, there is a 3.3 cm hypoenhancing lesion that blurs the enhancing cortex. Left kidney appears normal and there is no hydronephrosis.
There is a lesion centered in the interpolar to upper pole of the right kidney, internally heterogeneous and generally hypoenhancing compared to the rest of the renal parenchyma. Few tiny hyperenhancing foci are seen in the center and periphery of the mass. The largest foci is located centrally and may represent areas of internal necrosis or cystic components with or without a central scar. Features are suggestive of malignancy.
There is a well-defined focal isoechoic mass at the interpolar region of the right kidney that is predominantly solid and contains two small cystic foci within it. Central and peripheral vascularity is seen within the lesion, with arterial flow on Doppler. Internal areas of vascularity favors neoplastic etiology.
Case Discussion
Patient underwent right radical nephrectomy.
Histology
Gross: complete right kidney measuring 11 x 6 x 5 cm. There is a mass lesion in the mid-portion of the anterior-lateral aspect, relative to the ureter.
Microscopy: a well-demarcated, non-encapsulated tumor with infiltrative growth pattern and variable cytology and histology. Histologic patterns include microcystic, glandular, reticular, and solid. Tumor cells are pleomorphic with hyperchromatic, enlarged nuclei with prominent nucleoli. Some tumor cells contain abundant eosinophilic cytoplasm. Invidual cell necrosis is present without geographic necrosis. Focal perineural invasion is noted without vascular invasion. There are many normal renal tubules entrapped within the tumor and occasional glomeruli.
Immunohistochemical stains: Positive for CAM5.2, AE1/AE3, CK7, EMA. P53 stains 50% of the tumor nuclei. Tumor cells show loss of nuclear staining with INI1. Focal positive staining is noted for OCT3/4. Negative for CK30, PLAP, and Vimentin.
Final diagnosis: renal medullary carcinoma
Unable to process the form. Check for errors and try again.