De novo Renal Cell Carcinoma in a Kidney Allograft with Focus on Contrast-Enhanced Ultrasound

Abstract

The development of de novo renal cell carcinoma (RCC) in a transplanted kidney is a rare condition. Currently, this is the second case report of a 41-year-old man in whom carcinoma of a renal allograft was detected by contrast-enhanced ultrasound (CEUS). An abdominal CT scan was not conclusive enough to differentiate between septal enhancement of a cyst and a low vascularized tumor. CEUS confirmed a solid, homogeneously enhancing but hypoechoic and hypovascular lesion compared to the surrounding kidney parenchyma without septal enhancement. Therefore, the patient underwent nephron-sparing surgery (NSS), affirming papillary RCC type 2. Graft function remained unchanged postoperatively; 12 months after NSS, no local recurrence or distant metastasis was described. CEUS seems to be a minimally invasive and efficient imaging option if other diagnostic tools cannot clearly exclude RCC, with the advantage of wide-ranging use, especially in cases of impaired renal function.

Imaging of renal cell carcinoma

“…For example, in patients with kidney allografts, CEUS imaging can detect lesions not identified on CT [17]. On the contrary, another study showed de novo RCCs in kidney allograft patients with acquired cystic kidney disease that could not be detected using US, yet could be detected on native MRI [13].…”