Juxtaglomerulärer Zelltumor (Reninom)

A case of

atypical reninoma with mild hypertension and normal plasma renin activity but elevated plasma renin concentration. Abdominal contrast-enhanced CT and 18F-FDG PET-CT. A solid, circumscribed, low-density, cortical lesion (15 mm x13 mm) in the posterior lip of the left kidney, which appears to be moderately enhanced. There was no obvious enhancement in the arterial phase, but it was progressive in the venous phase and delayed phase. B mild FDG uptake in the mass

bmcendocrdisord.biomedcentral.com • CC-by-4.0

Radiopaedia • CC-by-nc-sa 3.0 • de

Juxtaglomerular cell tumors, also known as reninomas, are uncommon renal tumor of the juxtaglomerular cells. The tumor cells secrete renin and often cause severe hypertension and hypokalemia.

Epidemiology

Juxtaglomerular cell tumor affect all age groups, but are most common in adolescents and young adults, with peak prevalence in the second and third decades of life.

There is a female predominance.

Clinical presentation

Patients with a juxtaglomerular cell tumor present with headaches, dizziness, double vision, retinopathy, nausea, vomiting, and polyuria and most of these may be attributed to hypertension or hypokalemia. Reninoma may be a reason of cerebrovascular accident and death .

Pathology

Juxtaglomerular cell tumor is often well-circumscribed, yellow to gray-tan in color, with a complete or partial fibrous capsule usually observed. Histologically cytoplasm of tumor cells consisting of renin and solid sheets of closely packed round to polygonal cells .

Radiographic features

Imaging findings are variable.

Ultrasound

hypoechoic mass

CT

variable density with moderate enhancement during late phase after contrast administration

MRI

Reported signal characteristics include

T1: iso-signal intensity
T2: high-signal intensity

Treatment and prognosis

Complete tumor resection by radical or partial nephrectomy is the best treatment for juxtaglomerular cell tumor. Anti-hypertensive agents can be used to manage hypertension until definitive therapy is planned.

History and etymology

Juxtaglomerular cell tumor was originally described in 1967 by Robertson et al, but first named by Kihara et al. in 1968. Approximately 100 case reports have been published.

Differential diagnosis

On imaging consider other renal tumors such as