1. Interventional Radiology in the
renal tumor :
Biopsy and RF
P. Taourel (Montpellier)

2. • Diagnosis
• Treatment

3. Solid Tumors
Invasive tumor
=
Cancer
Staging
Fat
=
Angiomyolipoma
Characterized by imaging
Small tumors : adenocarcinoma ?,
oncocytoma? AML without fat
Diagnosis difficulties

4. Be careful with US in angiomyolipoma
AML
• Characteristics :
– Hyperechoic ≥ : sinusal fat
– Homogeneous
• Be careful
– Calcification
– Hypoechoic rim
• 30% of cancers are hyperechoic
• US can not characterize an
angiomyolipoma : CT
Cancer

5. AML diagnosis = fat
• < -20 UH
• Easy
AML typique (-60 UH)

6. • Tiny content of fat may be challenging
AML à faible contingent adipeux

7. CT identification of the fat
• Thin slice
Temps
néphrographique
• Adapted ROI
• ≤ - 20 UH
• No IV contrast
Sans injection,
coupes fines

8. How to recognize AML without fat
• 5 à 15%
• Orientation criteria
– STB
– Multiple AML in a young woman
– US
– Spontaneously hyperdense (=
muscle) + hypervascular
– Présence de vaisseaux anévrismaux
• MRI ?
• Biopsy +++
Biopsy : AML)

9. Solid Tumors
Invasive tumor
=
Cancer
Staging
Fat
=
Angiomyolipoma
Characterized by imaging
Small tumor without fat : adk, aml
without fat, oncocytoma
Diagnosis difficulties

10. CT
Temps cortical (artériel)
• Fast enhancement
(cortical phase)
• Washout
• Scarr hypodense :
central + small + starr
Temps néphrographique

11. Small oncocytoma < 4 cm
• Characterization : difficult
• Enhancement :
homogeneous
• Scarr : missing (10%)
Small homogeneous oncocytoma

12. • Solid tumor in multicystic
kidney
Biopsy= ONCOCYTOMA
No iv
cortical 35 sec
tubular 80 sec

13. Solid renal tumor without fat on CT ≤ 4
cms must be biopsied
• Only one tumor must be characterized : AML
• Incidence of benign lesion : 20% ( if ≤ 2 cms)
• Biopsy easy to perform

14. CT value to
characterize tumor
• Consecutive study of 99
solid renal tumor
without fat
• 18 G biopsy with FU
• CT accuracy
– B (25%) / M (75%)
Millet AJR 2011

15. CT findings
• Morphologic criteria
– siza
– Ball versus bean
– Segmental inversion
– scarr
– Interface with the parenchyma
• Critères cinétiques
– Enhancement intensity
– Time-course pattern

16. Metanephric
adenoma

17. Ischemia

18. ONCOCYTOMA
ADK

19. Wegener
Lymphoma

20. adk
oncocytoma

21. Inverted segment ADK
oncocytoma

24. A weak significant finding of
benignancy : progressive enhancement
•
•
•
•
Sen = 60%
Spe = 73%
PPV = 43% (prevalence of benignancy)
NPV = 84%
– AJR 2011 Millet et al

25. Tubulo-papillar adk

26. Biopy of small renal tumor is
mandatory
• Benign versus malignant : impact ++++
• Type of adk : impact ?
• Grade : impact +
– Partial surgery
– Temperature ablation
– Active FU

27. • 187 solid tumors ≤ 4cms
• 145 Malignant
• 132 renal cancers,
– 61 surgery
– 36 RF
– 35 FU
Millet J Urol 2012

28. Table 1
Biopsy-surgery correlation for the histologic subtype
Biopsy subtype
Surgical subtype
Clear cell
Clear cell
Chromophobe
Tubulopapillary
Unclassified
Chromophobe
Tubulopapillary
Unclassified
55
13
5
1

29. Table 2
Biopsy-surgery correlation for the Fuhrman grade
Biopsy grade
Surgical grade
G1
G1
G2
G3
G4
G2
G3
7
11
33
2
2
6
G4

30. To conclude on diagnosis :
the biopsy of renal tumor is
• Easy (LD if lesion in upper
part of the kidney)
• Accurate
• Useful (25% of benign
lesion)
• Mandatory (no CT
characteriation)
• Impact on treatment of adk
(weak underestimation of the grade)

31. • Diagnosis
• Treatment

32. Radiofrequency of renal tumors
• Why ? (overdiagnosis and
overtreatment ?)
• How ?
• What results ?
• When ?

34. → Ionic agitation
→ Friction with heat in the tissues
→ Thermal damage with heating
→ Nécrosis of coagulation (50 – 100 ° )
→ ≥ 100 ° carbonization with non
efficiency of the treatment

36. Radiographics
2001

38. What evaluation before ?
• Proof of malignancy (25% : B)
• Size of the lesion : < 3cm, 3-5 cm
• Localization de la lésion :
ball vs bean
central or not
• Contact = pleura, bowel, ureter

41. What technique ?
•
•
•
•
decubitus
Ureteral stent
Hydrodissection
Displacement of the mass by the electrode

45. What FU ?
• 2 questions :
– Efficiency
– Recurrence
• Sémiologie uniqvoque
– fat stranding
– Rim finding (no significance)
• Enhancement : residu or recurrence
– nodules or croissants (triphasic CT)

53. M2

54. What FU ?
• 2 questions :
– Efficiency
– Recurrence
• Sémiologie uniqvoque
– fat stranding
– Rim finding (no significance)
• Enhancement : residu or recurrence
– Cortico-medullary phase

56. M2

58. M8
FU : 2m, 6m, 1y, then every y

59. What results : ?
• Efficiency : 80 – 90 %
• Predictive factors :
– exophytic (oven effect)
– < 3 cm

64. What results ?
Excise,ablate or observe :
the small renal mass dilemna
J Urol 2008

65. What results : a metaanalaysis
age
PN
Cryoablation
RF
FU
5037 (77,8 %)
496 (7,7 %)
607 (9,4 %)
331 (5,1 %)
size
60
65,7
67,2
68,9
3,40
2,56
2,69
3,04
J Urol 2008

66. What results :
a meta analysis
FU (month)
Dgc
pathol : K
LR
2,6 %
4,6 %
11,7 %
PN
Cryoablation
RF
54
18
16
87 %
76 %
88 %
FU
33
91 %
M
5,6 %
1,2 %
2,3 %
0,9 %
J Urol 2008

67. Ablation of renal tumor :
(cryoablation or RF)
•
•
•
•
Tm < 4 cm
exophytic or parenchymateous
Age > 70 ans
cobormidity or failure renal factor risk
or
• Recurrence after partial nephrectomy
or
• VHL syndroma