Bilateral multifocal renal oncocytoma in pregnancy

Abstract

Renal oncocytomas are the most common benign solid renal tumor, accounting for 3-7% of renal neoplasms. Oncocytomas are multifocal in 2-12% and bilateral in 4-14% of cases. Multifocal bilateral oncocytomas represent only 1.4% of renal cases. We present an extraordinary case of a patient with multifocal bilateral renal oncocytomas during pregnancy. An electronic literature search revealed fewer than 30 reports of on cases of bilateral multifocal renal oncocytomas, none of them occurring in pregnancy. The management of this patient differed from the recommended guidelines for renal masses suspected to be malignant because elective caesarean section and nephrectomy in the second trimester was refused.

Keywords: bilateral; kidney; multifocal; oncocytoma; pregnancy.; renal.

Figure 1

Magnetic resonance imaging: abdomen coronal view, showing bilateral renal tumors.

Figure 2

Macroscopic appearance of the right kidney with multiple tumors.

Figure 3

Overview shows a tumor with a nesting growth pattern, eosinophilic cytoplasm and round nuclei (Haematoxylin and Eosin 10×).

Figure 4

The tumor cells have granular eosinophilic and round nuclei (Haematoxylin and Eosin, high power 100× magnification).