2. RENAL CELL CARCINOMA
• Renal cell carcinoma accounts for approximately 3%
of all adult malignancies and 86% of all primary
malignant renal parenchymal tumors.
• Male predominance
• Peak age is 50 to 70 years
4. INHERITED RCC
• Majority of RCCs – Sporadic
Estimated 4% RCC occur in inherited syndromes.
• Inherited RCCs occur at an earlier age, are multifocal
and bilateral, and affect men and women equally.
Von Hippel– Lindau (VHL) disease
is the most well-known inherited
RCC syndrome. 24% to 45% of VHL
patients will develop RCC
5. Other Inherited Syndromes
• Hereditary papillary renal cancer
• Birt-hogg- dubé syndrome
• Hereditary leiomyoma RCC
• Familial renal oncocytoma
• Hereditary nonpolyposis colon cancer
• Medullary RCC
7. SONOGRAPHIC EVALUATION OF RCC
• Most RCCs are solid at ultrasound.
• Tumors may be hypoechoic, isoechoic, or
hyperechoic.
• Macroscopic calcification may be identified in
8% to 18% of RCCs
9. CYSTIC RCCs
5% to 7% of all RCCs are cystic tumors.
Four histologic growth patterns within
cystic RCCs have been described:
Multilocular
Unilocular
Necrotic (cystic necrosis)
Tumors originating in a simple cyst
10. • Multilocular cystic RCC – cystic mass with internal
septations. These septations may be thick (>2 mm),
nodular, and may contain calcification
• Unilocular cystic RCC - debris-filled mass with thick,
irregular walls that may be calcified.
11. • Necrotic RCC - depends on the degree of tumor
necrosis.
• Tumors originating in a simple cyst are rare
(excluding VHL patients).
13. COLOR DOPPLER
• Most prominent color flow around periphery of mass.
• Variable flow depending on degree of necrosis & cystic
components.
15. ROBSON STAGING CLASSIFICATION
I: Tumor confined within renal capsule.
II: Tumor invasion of perinephric fat.
III: Tumor involvement of regional lymph nodes or venous
structures.
IV: Invasion of adjacent organs or distant metastases.
For patients with imaging findings (or biopsy results) definitive for RCC, the
stage at diagnosis directly impacts prognosis.
16. PITFALLS IN INTERPRETATION
• Ultrasound is inferior to CT and MRI for staging RCC.
• Obesity and overlying bowel gas often make it
difficult to assess for lymphadenopathy or vascular
involvement.
18. CT PROTOCOL
• Combination of nonenhanced and contrast-enhanced
CT in the corticomedullary and nephrographic
phases.
• Corticomedullary phase - 25-70 seconds from the
start of injection of contrast material is best for
evaluating venous extension of RCC.
• Nephrographic phase - 80-180 seconds after the start
of injection is best for evaluating the renal mass
20. Plain CT
• The precontrast CT appearance of RCC varies
considerably depending on the gross pathologic
features.
• Neoplasms may be hypodense, isodense or
hyperdense compared with normal renal
parenchyma on nonenhanced CT scans
22. TUMOR CALCIFICATION
• Tumor calcification occurs in 31% of cases and may
take the form of amorphous internal calcification or
curvilinear calcification - peripheral or central.
24. CONTRAST CT
Contrast-enhanced CT scan shows a
homogeneous 2.3-cm mass (white arrows)
with a slightly irregular outline. The
attenuation value increased from 37 to 87 HU.
A small rnal cyst (black arrow) is seen
anteriorly
Nephrographic-pase CT scan shows that the
mass (arrow) enhances less than normal renal
parenchyma and reveals low-density areas due
to tumor necrosis. The mass has an indistinct
interface with adjacent renal parenchyma
• After administration of IV contrast medium, most
RCCs enhance but usually to a lesser extent than
normal renal parenchyma
• Most RCCs are solid lesions with attenuation values
of 20 HU or greater on nonenhanced CT.
25. • Enhancement is often heterogeneous because of tumor
hemorrhage or necrosis .
• The mass often shows an indistinct interface with the
surrounding parenchyma and frequently has a lobulated
or irregular outer margin.
30. ENHANCEMENT PATTERN IN CT
NO ENHANCEMENT
• Cystic lesion
HOMOGENOUS
ENHANCEMENT
• Lipid poor AML
EQUIVOCAL
ENHANCEMENT
• Papillary RCC
• Cyst (Pseudo
enhancement)
– Suggested
MRI
STRONG
ENHANCEMENT
• Clear cell RCC
• Lipid poor AML
• Oncocytoma
31. MRI
• MRI assumes a primary role in tumor detection and
staging in patients in whom contrast-enhanced CT
scanning is contraindicated because of either previous
major reactions to contrast material or renal failure.
32. T1 WI - hypointense
to isointense to
renal parenchyma
T2 WI -
heterogeneously
hyperintense
Gd Contrast - less
enhancement than
renal parenchyma.
34. Gd-enhanced MRI of
renal cell carcinoma.
Coronal (T1-weighted
sequence with Gd)
image in the
nephrographic phase
demonstrates a mass
that enhances less than
the adjoining renal
parenchyma in the middle
pole of the right kidney.
35. T1-weighted Gd-enhanced MRI of the abdomen shows a large right renal lesion. B, Image at
slightly higher level shows extension of the tumor into the IVC (arrow). Also seen incidentally are
multiple enhancing liver lesions (arrowheads) consistent with metastatic disease.
36. Coronal reconstruction of contrast-
enhanced image of the same
patient again shows the renal
cell carcinoma with direct
extension into the IVC.
Thrombus within the IVC shows
heterogeneous enhancement
and is in continuity with the
primary tumor, suggesting a
tumor thrombus.
37. STAGING OF RENAL CELL CARCINOMA
• Prognosis of patients with RCC depends mainly on
the histologic tumor grade and the anatomic extent
or stage of the disease when first seen.
• RCC is now most commonly staged according to the
tumor, node, and metastases (TNM) system
38. T stage
T0 No evidence of primary tumor
T1 Tumor < 7cm in diameter and limited to kidney
T1a Tumor < /= 4cm in diameter and limited to kidney
T1b Tumor >4cm but < 7cm in diameter and limited to kidney
T2 Tumor > 7cm in diameter and limited to kidney
T2a Tumor >7cm but < 10cm in diameter and limited to kidney
T2b Tumor < 10cm in diameter and limited to kidney
39. T stage
T3 Tumor extends into major veins / perinephric tissues but not beyound
Gerotas fascia
T3a Tumor invades perinephric tisues not beyond Gerotas fascia
T3b Tumor extends to IVC below diaphragm
T3c Tumor extends to IVC above diaphragm
T4 Tumor extends beyond Gerotas fascia
40. REGIONAL LYMPH NODE
Nx Regional nodal metastasis could not be assessed
N0 No regional lymph node metastasis
N1 Regional lymph node metastasis
DISTANT METASTASIS
M0 No distant metastasis
M1 Distant metastasis
43. TREATMENT
• Nephron-sparing surgery
• Radical nephrectomy
(1) RCC in a solitary functioning kidney
(2) RCC in a patient with compromised
renal function
(3) Multiple bilateral tumors, which are
common in VHLD and hereditary RCC
Most suitable lesion for nephron-
sparing nephrectomy is smaller than 4
cm, polar, cortical, and far from the
renal hilum and collecting system.
44. R.E.N.A.L. NEPHROMETRY SCORE
(R)adius (scores tumor size as maximal diameter)
(E) xophytic/endophytic properties of the tumor
(N)earness of the deepest portion of the tumor to the collecting system or
renal sinus
(A)nterior (a)/posterior (p) descriptor
(L)ocation relative to the polar line.
Describes the anatomic characteristics of the renal tumor, considering five
specific descriptors of the mass.
45. • This standard scoring system helps in surgery
treatment decision making and potentially for
predicting outcome
47. PAPILLARY RCC
Papillary tumors account for 15% of all RCCs.
• Slower growth
• Lower stage at presentation
• Better prognosis
• No consistent sonographic pattern exists - Papillary
tumors also tend to be hypoechoic or isoechoic or
hyperechoic.
50. CT Findings
NECT
○ Hypo- to isoattenuating relative to renal parenchyma
○ Perinephric stranding: ~ 55%
○ Rare calcification
51. • CECT
○ Infiltrative, solid mass centered in
renal medulla
– Invasion of renal sinus: ~ 90-95%
○ Hypovascular to heterogeneous
enhancement
○ Preservation of renal contour >
expansile appearance
– Expansile component due to
ductal dilatation
○ Vascular invasion: ~ 25%
○ Cystic component: ~ 50
52. MR FINDINGS
• T1WI
○ Hypo- to isointense relative to renal parenchyma
• T2WI
○ Hypointense relative to renal parenchyma
53. MEDULLARY CARCINOMA
• Highly aggressive, infiltrative primary renal
malignancy
• Location - Originating in renal medulla but can
invade cortex and renal sinus..
• Age : < 25 years (typically between ~ 10-40
• Poor prognosis: Mean survival ~ 15 weeksyears)
54. Ultrasonographic Findings
• Grayscale ultrasound
Ill-defined mass with heterogeneous echotexture
• Color Doppler
Hypovascular tumors; color flow typically not
detected
55. CT Findings
NECT - Infiltrative soft tissue mass
Loss of normal renal architecture
CECT
Ill-defined, infiltrative, heterogeneously enhancing renal
mass with areas of necrosis and hemorrhage
Regional adenopathy and metastases common at
presentation
Metastases: Lymph nodes, lung, liver, adrenal glands,
pleura, omentum
56. Axial CECT in a patient
with sickle cell trait who
presented with right flank
pain and hematuria shows an
ill-defined, infiltrative mass in
the right kidney. The mass
enhances heterogeneously due
to areas of necrosis ſt. Note
the retrocaval adenopathy ſt
resulting in anterior
displacement of the IVC ſt.
57. MR Findings
T1WI - low signal intensity
― areas of high signal intensity due to hemorrhage
T2WI - low to intermediate signal intensity
○ Large areas of high signal intensity due to necrosis
○ Heterogeneity due to blood products of varying age
DWI - Restricted diffusion in areas of viable tumor
58. Axial T2WI MR with fat
saturation shows an ill-
defined
mass ſt that infiltrates the
renal cortex, medulla, and
collecting system. The
mass
has heterogeneous low to
intermediate signal
intensity.
59. Best diagnostic clue
Infiltrative renal mass with metastases
in young patient with sickle cell trait
Sickle cell trait→ chronic medullary hypoxia
– Hypoxia →transitional cell proliferation of
terminal collecting ducts and papillary
epithelium
64. Classic angiographic findings for oncocytoma
• Spoke-wheel pattern
• Homogeneous nephrogram
• Sharp smooth rim – Lucent rim sign.
65. If the diagnosis of oncocytoma is suspected before
surgery, small tumors may be treated with partial
nephrectomy because of the excellent prognosis.
66. RENAL ANGIOMYOLIPOMA
• Angiomyolipomas are benign hamartomas composed
of blood vessels, smooth muscle, and fatty tissue.
• The presence of intratumoral fat is almost diagnostic
of AMLs.
67. SONOGRAPHIC EVALUATION OF AML
Large, complex intrarenal mass is
mildly echogenic and has a
hypoechoic component representing
myomatous elements (M).
68. • A thin hypoechoic rim, pseudocapsule at histology,
was reported in 84% of RCCs and not in AMLs.
• Intralesional cystic spaces were shown exclusively in
several echogenic renal cell carcinomas
70. Difficulties
• 5% of AMLs do not show fat attenuation on CT scans
and cannot be differentiated from RCC.
• Extensive intratumoral hemorrhage may also obscure
the presence of fat.
• Fat has been reported in Wilms’ tumor in children
and in renal oncocytomas.
71. RENAL METASTASIS
• The kidney is the fifth most common site of
metastases in the body.
• Most metastases reach the kidney by the
hematogenous route.
• Three neoplasms with the highest frequency of renal
metastases are lung carcinoma, breast carcinoma,
and carcinoma of the other kidney.
72. Primary Nature of metastasis in kidney
Colon carcinoma Solitary exophytic metastases
Melanoma Perinephric tumor extension
Metastatic lesions are best seen on contrast-enhanced CT scans.
74. RENAL ABSCESS
• Renal abscesses are uncommon
• Abscesses are due to ascending infection, commonly
by Escherichia coli.
• Renal abscess formation is generally associated with
symptomatic urinary tract infection
75. • CT is the best technique for the diagnosis and staging
of renal and perinephric abscesses.
• The central portion of an abscess is of near-fluid
density and no enhancement on contrast
administration.
76. • There is often a thick irregular wall, which enhances
together with inflammatory changes in the
perinephric space.
• Presence of gas within a lesion is diagnostic of an
abscess but is very rarely seen
77. Large right renal abscess. The
lesion has an attenuation
value of 36 HU and shows a
thick wall. High-density renal
parenchyma on its
anteromedial aspect is
probably due to retention of
contrast medium in
compressed and obstructed
renal tubules on the periphery
of the abscess
78. TRANSITIONAL CELL CARCINOMA
• Can involve renal pelvis , ureter and bladder.
• Renal TCC is two to three times more common than
ureteral neoplasms.
• Bladder TCC, because of its large surface area, is 50
times more common than renal pelvic TCC.
79. RISK FACTORS
• Balkan nephritis
• Vesicoureteric reflux
• Multifocal recurrent bladder TCC
• High-grade bladder tumors
• Carcinoma in situ of distal ureters after cystectomy,
• Analgesic abuse
• Heavy smoking habit
• Exposure to carcinogens
• Cyclophosphamide therapy
80. TYPES OF TCC
Papillary TCC
• Exophytic polypoid lesions
attached to the mucosa by a
stalk
• Lower grade at presentation
• Infiltrates slowly
• Metastasizes late
Non Papillary TCC
• Nodular or flat tumors
• High grade
• Infiltrating
Mucosal thickening that is a
hallmark of sessile TCC may
be difficult to depict even
at CT
81. RENAL TCC
• Male >>> Female
• Elderly (Mean age - 65)
• MC presentation – Haematuria
82. RENAL SINUS FAT vs TCC
Small focal area of hypoechogenicity is seen within echogenic sinus fat in the
lower pole. Color Doppler image at the same level as B shows normal vessels running
through this area, confirming insignificant fat rather than tumor
83. SONOGRAPHIC EVALUATION OF RENAL TCC
• Morphology of the lesion (papillary, nonpapillary, or
infiltrative)
• Location
• Size
• Presence or absence of hydronephrosis
84. • Papillary tumors - discrete, solid, central, hypoechoic
renal sinus masses with or without associated
proximal caliectasis.
• Infiltrating TCC - distortion and enlargement of the
kidney and maintenance of an overall reniform
shape.
91. CT EVALUATION OF TCC
CT helps in establishing the extent of renal parenchymal
invasion, including the perinephric and periureteral
extents of tumor.
92. CT PROTOCOL
Nonenhanced abdomen and pelvis
Contrast-enhanced CT
• Corticomedullary phase
• Nephrographic phase
• Excretory-phase images
Slice thickness of 3 to 5 mm
Characteristically
hypovascular on
angiography, pelvicalyceal
tumors often show mild
enhancement on CT after IV
administration of contrast
medium
93. Polypoid transitional cell
carcinoma of the right renal
pelvis. The lesion invaded to
but not beyond the
muscularis. The lesion
enhanced on this scan by 36
HU.
94. Hydronephrosis due to
transitional cell carcinoma of
the right renal pelvis. A, A
soft tissue mass fills the
right renal pelvis. Dilated
calyces are seen in the right
kidney. An enlarged
retrocaval lymph node was
involved by metastatic
disease