Diagnostic Ultrasound - Abdomen and Pelvis

Renal Cell Carcinoma
Diagnoses: Urinary Tract
TERMINOLOGY
• Malignant tumor arising from proximal tubular epithelium
• Most common primary renal malignancy
IMAGING
• Clear cell adenocarcinoma (60-70%)
• Papillary (5-15%)
• Chromophobe (5%)
• Variable appearance: Solid, cystic, or complex
• Macroscopic fat practically excludes renal cell carcinoma
(RCC)
• Clear cell RCC: Hypervascular, heterogeneous, mixed
enhancement pattern with both enhancing soft tissue
components and areas of necrosis
• Papillary RCC: Hypovascular, typically homogeneous; may
be partly cystic
• Increasing role of percutaneous biopsy in selecting patients
for treatment or surveillance based on subtype
KEY FACTS
• RCC may be initially detected by US but CECT and MR are
primary tools for characterization and staging
• In select patients, US may be used for screening and followup
depending on body habitus
• MR/US preferred over CT for long-term surveillance based
on radiation concerns
• Ultrasound may be useful in characterizing complex cystic
lesions, which are indeterminate or equivocal on CECT or
MR
• Use Doppler (color/power/pulsed) for detection of internal
vascularity
TOP DIFFERENTIAL DIAGNOSES
• Renal angiomyolipoma
• Transitional cell carcinoma (TCC)
• Renal oncocytoma
• Renal metastases and lymphoma
• Column of Bertin
(Left) Graphic shows a
lobulated, solid, upper pole
renal carcinoma ſt. The renal
vein is expanded with
tumor thrombus, which
extends into the inferior vena
cava st. A 2nd tumor nodule
is seen . (Right)
Longitudinal ultrasound in a
patient with clear cell renal
carcinoma shows a solid,
slightly hyperechoic mass
within the calipers. There is an
incomplete hypoechoic rim st.
Note posterior acoustic
enhancement ſt.
(Left) Longitudinal ultrasound
shows an exophytic,
homogeneous, hypoechoic
chromophobe renal cell
carcinoma (RCC) with
infiltration and distortion of
the renal sinus fat st. (Right)
Transverse ultrasound of the
same patient shows a solid,
hypoechoic, exophytic
chromophobe RCC with
peripheral ſt and internal
color flow .
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