Tubulocystic renal cell carcinoma

Tubulocystic
renal cell carcinoma in the left kidney: a case report. Enhanced abdominal computed tomography. An abdominal computed tomography image showing a hemorrhagic cyst in the upper pole of the left kidney (arrowheads).
jmedicalcasereports.biomedcentral.com • CC-by-4.0
Tubulocystic
renal cell carcinoma in the left kidney: a case report. Abdominal magnetic resonance imaging. A T2-weighted magnetic resonance image showing a high-intensity tumor (arrowheads).
jmedicalcasereports.biomedcentral.com • CC-by-4.0
Synchronous
clear cell renal cell carcinoma and tubulocystic carcinoma: genetic evidence of independent ontogenesis and implications of chromosomal imbalances in tumor progression. Imaging, Computed tomography (CT) showed the presence of two incidental well-circumscribed masses with similar density in the right kidney. The larger lesion was solid and enhancing and measured 3.5 cm; it was located in the upper pole and approached but did not extend into the renal sinus (black arrow). The smaller lesion measured 1.2 cm and was located along the mid lateral aspect of the kidney (white arrow). The contralateral kidney was normal.
diagnosticpathology.biomedcentral.com • CC-by-2.0
Radiopaedia • CC-by-nc-sa 3.0 • de

Tubulocystic renal cell carcinomas are a rare subtype of renal cell carcinoma (RCC) with predominantly cystic appearance.

Terminology

Tubulocystic RCC was first identified as a distinct histopathologic entity in 2005, and subsequently acknowledged as an independent disease category in the 2016 WHO classification of renal tumors .

Epidemiology

Peak incidence occurs in the 6 through 8 decades.

Males are much more commonly affected than females (7:1 ratio).

Associations

Clinical presentation

Most patients are asymptomatic and the tumor is discovered incidentally.

Pathology

Macroscopically, the tumors are well-circumscribed lesions comprising extensive tiny cysts with numerous thin septa, resulting in a spongy or "bubble wrap" appearance. Microscopically, the tumor is composed of tubular and cystic spaces separated by fibrous stroma.

Limited information from genetic studies suggest gene expression similar to papillary RCC .

Radiographic appearance

Ultrasound
CT 
  • variable attenuation so may appear solid or cystic
  • C+: contrast enhancement is usually mild or indeterminate given small amount of solid tissue
MRI
  • T2: hyperintense due to cystic component, with septa
  • T1 C+ (Gd): mild enhancement in small solid components or wall

Treatment and prognosis

Surgical resection is curative. Recurrence and/or metastasis occur in less than 10% of cases.

Differential diagnosis

See also

Siehe auch: