1. Ultrasound of the urinary tract
Renal tumors
Samir Haffar M.D.
Department of Internal Medicine

2. Ultrasound of renal tumors
• US is often the first imaging modality of kidneys
• Plays important role in diagnosis of renal tumors
• Technical advances improved detection of renal tumors
Tissue harmonic imaging (THI)
Color Flow Doppler
Contrast-enhanced Doppler
CT is the gold standard for detection &
characterizationof renal mass lesions

3. Normal kidney
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

4. Benign & malignant renal tumors
 Pseudo-lesions of kidney
 Benign tumors
 Malignant tumors: Renal cell carcinoma
Tumors of renal collecting system
 Renal metastases
 Renal lymphoma
 Leukemic involvement of kidney
 Percutaneous biopsy for renal masses
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

5.  Pseudo-lesions of kidney

6. Pseudo-lesions of kidney
• Congenital normal variants Dromedary hump
Persistent fetal lobulation
Prominent column of Bertin
Junctional parenchymal defect
Hypoechoic renal sinus
• Inflammatory lesions Focal bacterial nephritis
“clinical context” Renal abscess
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

7. Dromedary hump
Common renal variation
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Focal bulge on lateral border of left kidney
Result from adaptation of renal surface to adjacent spleen
Easily differentiated from renal mass: US – Doppler

8. Persistent fetal lobulation
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Renal surface indentations between pyramids
May be single or multiple

9. Persistent fetal lobulation
Renal surface indentations between pyramids
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Multiple fetal lobulations

10. Prominent column of Bertin (PCB)
Mistaken for intrarenal tumor
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Continuity with renal cortex
Similar echo as renal parenchyma
Less than 3 cm in size
Contains renal pyramids
Similar vascular pattern by color Doppler

11. Prominent column of Bertin (PCB)
Medullary pyramids
seen within PCB
Sagittal sonogram
Classic appearance
Transverse sonogram
Classic appearance
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.

12. Parenchymal junctional defect
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Commonly mistaken for cortical scar or angiomyolipoma
Continuity with central sinus
by echogenic line
Triangular hyperechoic structure
Antero-superior or postero-inferior
surface of kidney “interrenicular septum”

13. Hypoechoic renal sinus
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.
Fat-filled hypoechoic renal sinus mimicking mass lesion
Absence of a well-defined margin
Normal vessels traversing renal sinus by CFD

14.  Benign renal tumors

15. Benign renal tumors
• Angiomyolipoma Sporadic – Associated with TS
• Adenoma Benign counterpart of RCC
Tumors < 3 cm rarely metastasize
• Oncocytoma Tumor of renal tubular origin
Differentiation from RCC difficult
Hypo, iso, or hyperechoic to cortex
• Leiomyoma Rare, peripheral or central
Solid, mixed, or cystic lesion
• Reninoma
• Hemangiopericytoma
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

16. Angiomyolipoma (AML)
Hamartoma (mature adipose tissue, SM, blood vessels)
• Sporadic (80%) Middle-aged women, unilateral
Tuberous sclerosis (20%) Younger, multiple, bilateral, larger
• Grows during pregnancy & presents with hemorrhage
Retroperitoneal bleeding (Wunderlich’s syndrome):10%
Risk of rupture: > 4 cm – microaneurysms > 5 mm
• Management: observation – embolization – renal-sparing surg
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Overlap between imaging features of AML & small RCC

17. Sonography of angiomyolipoma
• Classic pattern Well-defined hyperechoic mass
Posterior acoustic shadowing
Small RCC Well-defined hyperechoic mass
Hypoechoic rim
Intratumoral cystic changes
• Hypoechoic pattern Vessels or bleeding predominate
• Hemorrhagic pattern Central – perirenal
Depends on proportion of fat, SM, vessels & bleeding
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.

18. Angiomyolipoma – Classic pattern
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
CT (excretory phase)
Fat attenuation lesion
Household unit of – 8
Well defined hyperechoic mass
Posterior acoustic shadowing
Longitudinal US of right kidney
Intra-tumoral fat on CT almost confirms diagnosis of AML

19. Renal intratumoral fat attenuation
Logue LG et al. RadioGraphics 2003; 23:241–246
Almost pathognomonic for AML
Rare benign & malignant tumors considered
• Renal cell carcinoma
• Lipoma & liposarcoma
• Myolipoma
• Oncocytoma
• Wilms tumor

20. Angiomyolipomas (AMLs)
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.
Large exophytic AML
Large exophytic AML
Central hemorrhage
Exophytic AML
Perirenal hematoma

21. Atraumatic renal & perirenal hemorrhage
• Malignant renal tumors Most common cause
• Benign renal tumors AMLs
• Vasculitis
• Aneurysm
• Systemic anticoagulation
• Infection
• Nephritis
Logue LG et al. RadioGraphics 2003; 23:241–246

22. Tuberous sclerosis / Bourneville disease
Autosomal dominant disease (prevalence: 1/10 000)
• Hamartomatous growth CNS, eye, skin, heart, liver, kidney
• Classic clinical triad Mental retardation
Seizures
Adenoma sebaceum (angiofibroma)
• CNS manifestations Subependymal hamartomas
(90%) Giant cell astrocytomas
• Renal manifestations Angiomyolipomas (AMLs)
(50%) Renal cysts
Renal cell carcinomas (RCC)

23. Tuberous sclerosis (Bourneville disease)
Features central to diagnosis Adenoma sebaceum
Nontraumatic ungual periungual fibroma
Hypomelanotic macules (three or more)
Shagreen patch (connective tissue nevus)
Multiple retinal nodular hamartomas
Subependymal nodule
Subependymal giant cell astrocytoma
Cardiac rhabdomyoma (single or multiple)
Renal angiomyolipoma
Less specific features Multiple pits in dental enamel
Hamartomatous rectal polyps
Bone cysts
Gingival fibroma
Retinal achromic patch
“Confetti”skin lesions
Multiple renal cysts
Logue LG et al. RadioGraphics 2003; 23:241–246

24. Tuberous sclerosis
Multiple subependymal hamartomas
T2 axial MR of brain T2 coronal MR of brain
Weber TM. Ultrasound Clin 2006 ; 1 : 15 – 24.
Primary diagnostic feature

25. Renal cysts seen in cortex & medulla
Appear at an earlier age than cysts seen in APKD
Tuberous sclerosis
Multiple renal cysts
Weber TM. Ultrasound Clin 2006 ; 1 : 15 – 24.
Not primary diagnostic feature

26.  Malignant renal tumors

27.  Malignant renal tumors
Renal cell carcinoma
Tumors of renal collecting system

28. Renal cell carcinoma
Most common primary malignancy of kidney
• 2% of all malignancies
• Increase incidence of RCC
• Improved survival rates
• Improved imaging technique & early diagnosis
• Classified histologically into five main types
• Mainly sporadic in occurrence, 4% familial in nature
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

29. WHO classification of renal cell carcinoma – 2004
Type Incidence Grade Imaging features
Clear cell carcinoma 70 – 80% Low-grade tumor Poor enhancement
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Papillary type
Type 1
Type 2
10 – 15%
Low-grade tumor
Aggressive tumor
Poor enhancement
Intense enhancement
Chromophobe type 5% – –
Collecting duct type < 1% Aggressive tumor –
Medullary carcinoma < 1% Aggressive tumor
Common in sickle cell trait
–
Imaging cannot differentiate different histologic types of RCCs

30. Clinical presentation of RCC
• Clinical triad Hematuria
< 10% Abdominal pain
Abdominal mass
• Paraneoplastic synd Anemia, fever, hypertension,
20 – 40% hypercalcemia, hepatic dysfunction
• Stauffer syndrome Nonmetastatic IH cholestasis
Rare Tumor-induced inflammatory response
Reversible after resection of tumor
• Left-sided varicocele Renal vein involvement
2%
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

31. Sonographic findings of RCC
• Hyperechoic mass < 3 cm – differentiated from AML
Anechoic rim (pseudocapsule)
Intratumoral cystic changes
• Isoechoic mass Differentiated from pseudo-tumors
Power Doppler & CEUS
• Hypoechoic mass
• Cystic mass (15%) Extensive necrosis of tumor
Multilocular Cystic RCC (MCRCC)
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.

32. Renal cell carcinoma
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Hypoechoic mass
in lower pole
Gray-scale US Color Doppler
Presence of vascularity
Pulsed Doppler
Arterial wave

33. RCC & arteriovenous fistula
Prando A et al. RadioGraphics 2006 ; 26 : 233 – 244.
Large A-V fistula within renal tumor
Fistula associated with intense venous flow to left renal vein
& periureteral veins causing ureteral notching

34. Intrarenal & venous propagation of RCC
Intrarenal propagation of lower-pole RCC to upper pole
Renal vein thrombus, IVC invasion,
& extensive collateral venous circulation
Prando A et al. RadioGraphics 2006 ; 26 : 233 – 244.

35. Intrarenal propagation of RCC
Exophytic hypoechoic solid mass (M)
Unusual diffuse hypoechogenicity of renal parenchyma (*)
Longitudinal US image of left kidney
Prasad SR et al. RadioGraphics 2006 ; 26 : 1795 – 1810.

36. Venous thrombosis in RCC
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.
Enormous thrombus distending LRV
as it crosses midline anterior to aorta
Transverse sonogram
Large thrombus of IVC that
terminates caudal to level of HV
Sagittal sonogram of IVC

37. ADPKD & solid mass
Weber TM. Ultrasound Clin 2006 ; 1 : 15 – 24.
Solid renal masses in right kidney
Papillary renal cell carcinoma following nephrectomy
No increased risk for RCC in ADPKD except risk related to dialysis

38. Acquired cystic kidney disease with dialysis
ACKDD
Shrunken end-stage kidneys
Frequency increases with duration of dialysis
Complications: infection, hemorrhage, stone, erythocytosis, neoplasm
Screen native kidneys even after RT
Bates J A. Abdominal Ultrasound: How, Why and When.
Churchill Livingstone, Edinburg, UK, 2nd edition, 2004

39. Collecting duct carcinoma
< 1% of RCCs – Aggressive neoplasm
Prasad SR et al. RadioGraphics 2006 ; 26 : 1795 – 1810.
Solid hypovascular medullary neoplasm
Power Doppler sonogram

40. Cystic growth patterns of renal cell carcinoma
Yamashita Y et al. Acta Radiologica 1994 ; 35 : 19 – 24.
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.
Multilocular
Unilocular
Cystic necrosis
Origin in wall of
simple cyst

41. Multilocular Cystic RCC (MCRCC)
3% of all RCCs
Kim JC et al. Korean J Radiol 2000 ; 1 : 104 – 109.
Multiloculated cystic mass
Enhanced thin septa without nodules
Some enhanced solid portions
CECT
Multilocular cystic mas
Multiple echogenic thin septa
Echogenic debris (blood clots)
Longitudinal US of right kidney

42. Cystic renal cell carcinoma
Complex cystic mass
4 thick internal septa
US of right kidney CECT
Enhancing soft-tissue
components within cyst
US 4 years later
Cystic mass with several
solid nodular components
Bosniak category III Bosniak category IV
Adilson P et al. RadioGraphics 2006 ; 26 : 233 – 244.

43. Bosniak classification of renal cysts
Category CT features Significance
Class I Water density homogenous
Noncalcified, smooth margin
No enhancing component
Benign
Chapple CR et al. Practical urology: Essential principles & practice.
Springer-Verlag, London , 2011.
Class II Thin septae (<1 mm)
Thin calcification (<1 mm)
Hemorrhagic cyst
Benign
Class IIF Likely benign
Follow-up imaging indicated
Class III Thick septa
Thick calcification
Thick wall
Multilocular +/− enhancement
≈ 50% malignant
Class IV Criteria of category III
Enhancing solid mass of wall or septa
Definitely malignant

44. Systematic screening for RCC by US
• 2-year screening program for general population (≥ 40 years)
• 2 urology departments at Mainz & Wuppertal university hospitals
• GP, internists & urologists experienced in renal US
• Equivocal or positive renal mass: referral to urology departments
• 9959 volunteers in first year, 79% returned in second year
• 13 subjects have renal mass (0.1%), 9 were RCC
• PPV of positive finding 50% & for equivocal finding 2%
Filipas D et al. BJU Int 2003 ; 91 : 595 – 9.
Screening program accepted by physicians & eligible population
Effective method if equivocal findings reassessed by reference
US before using further imaging studies (CT or MRI)

45. Sporadic & hereditary renal cancers
Choyke PL et al. Radiology 2003 ; 226 : 33 – 46.
Sporadic renal cancer
96%
Hereditary renal cancer
4%
Single Multiple & bilateral
Advanced age Younger age
More common in men Equal frequency in both sexes
Detected at larger size Detected at smaller size (screening)

46. Hereditary renal cancers
• von Hippel-Lindau disease (VHL)
• Tuberous sclerosis (TS)
• Hereditary papillary renal cancer
• Birt-Hogg-Dubé syndrome
• Hereditary leiomyoma renal cell carcinoma
• Familial renal oncocytoma & oncocytomatosis
• Hereditary nonpolyposis colon cancer (HNPCC)
• Medullary carcinoma of kidney (sickle cell trait)
Choyke PL et al. Radiology 2003 ; 226 : 33 – 46.

47. von Hippel-Lindau disease
Rare disease (prevalence 1/ 35.000 – 40.000)
• Autosomal dominant disease with high penetrance
• Development of variety of benign & malignant tumors
• Broad clinical manifestations: 40 lesions in 14 organs
• Diagnostic criteria
More than one CNS hemangioblastoma
One CNS hemangioblastoma & visceral manifestations
Any manifestation & familial history of VHL disease

48. Manifestations of VHL Disease
40 different lesions in 14 different organs
Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.
Manifestations Prevalence
Pancreatic cysts
Cerebellar hemangioblastoma
Renal cysts
Retinal hemangioblastoma
Renal cell carcinoma
Spinal cord hemangioblastoma
Pheochromocytoma
Neuroendocrine tumor of pancreas
Serous cystadenoma of pancreas
Medullary hemangioblastoma
Papillary cystadenoma of epididymis
50 – 91%
44 – 72%
59 – 63%
45 – 59%
24 – 45%
13 – 59%
0 – 60%
5 – 17%
12 %
5 %
10 – 60%

49. Manifestations of VHL Disease
40 different lesions in 14 different organs
Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.
Manifestations Prevalence
Pancreatic cysts
Cerebellar hemangioblastoma
Renal cysts
Retinal hemangioblastoma
Renal cell carcinoma
Spinal cord hemangioblastoma
Pheochromocytoma
Neuroendocrine tumor of pancreas
Serous cystadenoma of pancreas
Medullary hemangioblastoma
Papillary cystadenoma of epididymis
50 – 91%
44 – 72%
59 – 63%
45 – 59%
24 – 45%
13 – 59%
0 – 60%
5 – 17%
12 %
5 %
10 – 60%

50. Retinal hemangioblastoma
Retinal angioma
Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.
Well defined orange-red mass
Prominent feeding artery
Prominent draining vein
Ophthalmoscopic image Fluorescein angiogram
Retinal angioma with
its hyperfluorescence

51. von Hippel-Lindau disease (VHL)
Renal cysts (60%)
Simple renal cyst
Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.
Complex renal cyst
Thick walls
Septa
Mural nodules
Anechoic contents
Sharply defined smooth wall
Posterior acoustic shadowing

52. Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.
Multiple lesions of mixed echotexture
Multiple RCCs
von Hippel-Lindau disease (VHL)
Renal cell carcinoma (25 – 45%)
Sagittal US of left kidney CECT scan
Simple cysts
Solid enhancing lesions
Right nephrectomy (RCCs)
CBD stent (pancreatic cysts)

53. Screening protocol for VHL disease
Body System Regimen Follow-up
Renal Annual abdominal US from 10 y CT or MR
Depending on US findings
CNS MRI of brain & spine at 20 y
Annual neurologic exam if symptoms
Repeat imaging if suspicion
Adrenal Annual 24-h urinary VMA from 10 y
Annual blood pressure measurement
Imaging if VMA abnormal
Ophthalmic Annual ophthalmoscopy from 5 y
With or without fluorescein
–
Auditory Questionnaire
Audiogram if questionnaire positive
MRI If audiogram abnormal
Leung RS et al.. RadioGraphics 2008 ; 28 : 65 – 79.

54. Birt-Hogg-Dubé syndrome
Fibrofolliculomas, pulmonary cysts, & renal tumors
Choyke PL et al. Radiology 2003 ; 226 : 33 – 46.
Transverse chest CT scan
Several small pulmonary cysts
Asymptomatic 38-year-old woman
Screening because of family history of this syndrome
Transverse abdominal CT scan
Multiple solid renal cancers
Chromophobe carcinomas at surgery

55. Clinical criteria for diagnosis of HNPCC*
Amsterdam criteria II
• At least 3 relatives with HNPCC-associated cancer:
CRC, endometrium, small bowel, ureter, or renal pelvis
• One should be a first-degree relative of the other 2
• At least 1 should be diagnosed before age 50
• At least 2 successive generations should be affected
• Familial adenomatous polyposis should be excluded
• Tumors should be verified by pathological examination
* HNPCC: Hereditary Non-Polyposis Colon Cancer
Vasen HFA et al. Gastroenterology 1999 ; 116 : 1453 – 8.

56. Screening for hereditary renal cancer
No established guidelines
Choyke PL et al. Radiology 2003 ; 226 : 33 – 46.
Number of generalizations can be made
CT scan is the best single choice for screening
MRI if patients cannot undergo CECT (RF, allergy)
US not recommended (insensitive for small renal masses)
Mild phenotype Imaging every 2 – 3 years
Aggressive phenotype Imaging every 3 – 6 months
Intervals vary Longer interval for small lesions

57. Uroepithelial tumors of renal collecting system
• Transitional cell carcinomas (TCC) 90%
• Squamous cell carcinomas 5-0%
• Adenocarcinomas < 1%

58. Transitional cell carcinoma
Mass in renal pelvis causing slight hydronephrosis
in keeping with transitional cell carcinoma
Chapple CR et al. Practical urology: essential principles and practice.
Springer-Verlag, London , 2011.

59. Transitional cell carcinoma
Tissue harmonic imaging (THI)
Schmidt T et al. AJR 2003 ; 180 : 1639 – 1647.
Fundamental B-mode sonogram
Tumor of upper pole of kidney
Slightly hypoechoic to renal sinus
Border of process not well defined
Phase-inversion THI
Fewer scattering artifacts
Tumor better delineated
Internal structure of process visible

60. Better lateral & axial resolution
Enhanced signal-to-noise ratio
Reduced artifacts
Theoretic advantages of THI
Less degradation of sonographic images

61. Causes of upper tract filling defects
• Calculus
• Thrombus
• Tumor
• Sloughed papilla
• Fungus ball
• Pyelo-ureteritis cystica
Chapple CR et al. Practical urology: essential principles and practice.
Springer-Verlag, London , 2011.

62. Pyeloureteritis cystica
Rare abnormality (200 published cases)
• Older individuals, males = females, bilateral in 1/3
• Cause: irritating agent on epithelium especially infection
• Epithelial bodies below mucosa: cell nests of von Brunn
• Not appear to be premalignant lesion
• Symptoms: accidental, lumbar pain, UTI, hematuria
• IVP or retrograde urography is gold standard for dg
Multiple small (2–3mm) smooth filling defects
• No specific treatment
Salpigidis G et al. Hipokratia 2010, 14, 4 : 284 – 285.

63. Pyeloureteritis cystica
Chapple CR et al. Practical urology: essential principles and practice.
Springer-Verlag, London , 2011.
Duplex collecting system
Multiple rounded filling defects within left renal pelvis & ureters

64. Squamous cell carcinoma
Enlarged kidney
Chunky calcification with AS
Longitudinal US of left kidney CFD of left kidney
Increased vascularity in the mass
Large areas of necrosis
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Difficult to differentiate from XGPN by imaging

65.  Renal metastases

66. Renal metastases
Multiple hypoechoic mass
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Most common primary tumors: lung, breast, GIT, & melanoma
Most common appearance: multiple hypoechoic cortical masses
Usually asymptomatic

67. Renal metastases
Multiple hyperechoic mass
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Right kidney Left kidney

68. Schmidt T et al. AJR 2003 ; 180 : 1639 – 1647.
Metastatis of small cell bronchial carcinoma
Tissue harmonic imaging (THI)
Fundamental B-mode sonogram
Suspicious hypoechoic lesion
adjacent to right kidney
Phase-inversion THI
Clear solid exophytic mass
Hypoechoic rim (arrow)
Features of kidney clearly delineated

69.  Renal lymphoma

70. Renal lymphoma
Solitary lesion
Multiple lesions
Diffuse infiltration of one or both kidneys
Renal sinus involvement
Preferential involvement of perinephric space
Direct extension from retroperitoneal adenopathy
Wide variety of manifestations
Sheth S et al. RadioGraphics 2006 ; 26 : 1151 – 1168.
Unless renal lesion manifests in setting of widespread
lymphoma, percutaneous biopsy is indicated

71. Renal lymphoma
Solitary lesion (10 – 25% of patients)
Sheth S et al. RadioGraphics 2006 ; 26 : 1151 – 1168.
CECT scan
Low-attenuation mass in left kidney
thick walls lesion
Stranding in perinephric space
Transverse US of left kidney
Complex partially cystic mass
Thick wall & multiple septa
Minimal through transmission

72. Renal lymphoma
Multiple lesions (Most common, 50 – 60%)
Hypoechoic parenchymal masses
Normal shape of kidney
Transverse US of right kidney
Sheth S et al. RadioGraphics 2006 ; 26 : 1151 – 1168.
CECT scan
Bilateral renal masses
Lower attenuation than cortex
Paraaortic retroperitoneal adenopathy

73. Renal lymphoma
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Diffuse infiltration of one or both kidneys
Longitudinal gray-scale US of left kidney
Nephromegaly without distortion of the normal shape
More common in Burkitt lymphoma (disseminated or limited)
14.8 cm

74. Renal lymphoma
Renal sinus involvement – Uncommon
Poorly defined infiltrating
mass in renal pelvis
Sagittal US of left kidney Color Doppler US
Well vascularized kidney
Hypovascular mass
Sheth S et al. RadioGraphics 2006 ; 26 : 1151 – 1168.

75. Renal lymphoma
Preferential involvement of perinephric space (10% )
Differential diagnosis
Sarcoma from renal capsule
Metastases to perinephric space
Perinephric hematoma
Retroperitoneal fibrosis
Amyloidosis
Extramedullary hematopoiesis
Surrounding hypoechoic
perirenal mass
Rumack CM et al. Diagnostic Ultrasound. Elsevier-Mosby, St. Louis, USA, 3rd edition, 2005.

76. Renal lymphoma
Paspulati RM et al. Ultrasound Clin 2006 ; 1 : 25 – 41.
Direct extension from retroperitoneal adenopathy
Large hypoechoic mass
displacing & infiltrating left kidney
Mild hydronephrosis
Sagittal US of left kidney Transverse color Doppler
Mass encasing left renal artery
& vein

77.  Leukemic involvement of kidney

78. Leukemic involvement of kidney (rare)
• Focal renal mass (chloromas)
Acute myelogenous leukemia: seen in 10% of patients
Acute lymphocytic leukemia: less common
Focal hypovascular soft-tissue masses in one or both kidneys
• Diffusely infiltrating renal mass
• Perirenal mass
Perinephric extension of renal lesion
Isolated leukemic involvement
Surabhi VR et al. RadioGraphics 2008 ; 28 : 1005 – 1017.
Nonspecific imaging findings
Biopsy required to obtain definitive diagnosis

79. Leukemic involvement of kidney
Pickhardt PJ et all. Radiographics 2000 ; 20 : 215 – 243.
Leukemia in a 3-year-old boy with hypertension
Longituinal sonogram of right kidney
Enlarged heterogenous kidney
Loss of normal corticomedullary differentiation

80.  Percutaneous biopsy in renal masses

81. Role of percutaneous biopsy in renal masses
Silverman SG et al. Radiology 2006 ; 240 : 6 – 22.
Established indications (sufficient data)
Emerging indications (more studies needed)
• Renal mass & known extrarenal primary malignancy
• Renal mass & findings suggesting unresectable renal cancer
• Renal mass & surgical comorbidities
• Renal mass that may be caused by infection
• Small, hyperattenuating, homogeneously enhancing renal mass
• Renal mass for which percutaneous ablation is considered
• Indeterminate cystic renal mass

82. Complications of renal biopsy for mass
• Bleeding Most frequent complication
Usually subclinical (90% by CT)
Major bleeding (transfusion) uncommon
PA & A-V fistula: months after biopsy
• Pneumothorax Uncommon
• Seeding along needle track: extremely rare (0.01%)
Silverman SG et al. Radiology 2006 ; 240 : 6 – 22.

83. Thank You