Percutaneous ablation of renal cell carcinoma Where do we stand - - PowerPoint PPT Presentation

Percutaneous ablation

• f renal cell carcinoma

Where do we stand now?

Sanja Stojanović, Spasić Aleksandar

Clinical Center of Vojvodina / Center for Radiology Novi Sad Serbia

Renal cell carcinoma

• approximately less than 4 % of all new cancers

in the western world

• The detection rate has been increasing in

recent years

• Incidental finding

Which RCCs are we speaking about

• T1

– T1a: tumour confined to kidney, <4 cm – T1b: tumour confined to kidney, >4 cm but <7 cm

• T2:
• T3:
• T4:

deployment of thermal energy

Treated area

4 cm

ELECTRODES

How to enlarge area of ablation

Thermal conduction from small heating zone Mechanism of celullar injury Central zone – necrosis Periphery - sublethal Immune activation – antigen presentation

Hyperthermic ablation

in depth understanding of the mechanism

Chu CF, Dupuy D. Thermal ablation of tumours: biological mechanisms and advances in therapy. Cancer; 2014.

Liquefied gases (Argon)

• 20 to -40°C

1cm beyond the lesion Mechanism of cellular injury Even better immune activation

• sometime inactivation

Cryoablation

Chu CF, Dupuy D. Thermal ablation of tumours: biological mechanisms and advances in therapy. Cancer; 2014.

Immunomodulation

Often too weak to completely

• vercome disease

Synergy with ablation

• imunnoadjuvants

Chu CF, Dupuy D. Thermal ablation of tumours: biological mechanisms and advances in therapy. Cancer; 2014.

Partial Nephrectomy Thermal Ablation

PATIENT SELECTION BIAS

• Patients that are not fit or are not willing to undergo surgical treatment
• Active surveilance only for those patients with cT1a RCC that cannot undergo

percutaneous treatment

• Armamentorium
• Lethal mechanism
• Immunomodulation
• Pathology
• Image guidance
• Effect of procedure

Partial Nephrectomy Thermal Ablation

Cornelis FH et al. A Comparative Study of Ablation Boundary Sharpness After Percutaneous Radiofrequency, Cryo-, Microwave, and Irreversible Electroporation Ablation in Normal Swine Liver and Kidneys. CIRSE; 2017.

RF CRYO

Metastases T1a – 7% RCC 3-4cm – 11% Further therapy by oncologists

Fuhrman grading

Disease Specific Survival (months) Percentage Survival

18G needle Multiple subtypes of RCC =yopsy CC Pathology CC blaDon Comparisson with other modalities (PN)

=iopsy - mandatory

Patient selection

• Small renal mass: T1a;

T1b ?

• Comorbid conditions
• Advanced age
• Single kidney
• Multiple masses (VHL)

Ideal lesion for RF

• Small (≤ 3cm/4cm?)
• Posterior
• Exophytic
• Far away from critical

structures

Proximity of spleen Multiple tumours Proximity of colon Proximity of hilus

• pyeloureter
• vascular

Image guidance

CT US – inferior control ablation induced artifacts MRI – robust equipement availibility

Hydrodissection

to push away structures in close proximity infusion of liquid

RCC colon

One needle Two needles

Complications

Hemorrhage (thinner or thicker needles)

– Subcapsular – Retroperitoneal

Hematuria

– Central locations – Cryoablation better tolerated by pyelocaliceal wall – Pyeloperfusion (cold or warmed liquids)

Atwell TD et al. Percutaneous Ablation of Renal Masses Measuring 3.0 cm and Smaller: Comparative Local Control and Complications After Radiofrequency Ablation and Cryoablation. AJR; 2013.

Prediction

• f complications

Radius Exophytic/endophytic Nearness to collecting system Anterior/posterior Location relative to polar lines

Schmit GD et al. Usefulness of R.E.N.A.L. Nephrometry Scoring System for Predicting Outcomes and Complications of Percutaneous Ablation of 751 Renal Tumors. J.Urology; 2013.

R.E.N.A.L. Score 4 - 6 7 - 9 10 - 12 % Major Complication

Prediction

• f local success

Radius Exophytic/endophytic Nearness to collecting system Anterior/posterior Location relative to polar lines

4 - 6 7 - 9 10 - 12

Months Post Treatment % Local Failure

Approach

90° angle

Electrode position

Skin landmark

RF or PN

• Renal reserve
• Partial nephrectomy or

thermal ablation ?

• Control of complications

Single kidney / multiple RCC

T1a lesion

26mm lesion Position 1 Position 2 After ablation

Control sectional imaging

• 4 weeks after ablation – rest of the ablated tumour
• after 3, 6, 9 or 12 months – institution protocol
• G' Kli8uidL complicaDons 92#dronephrosis, CollecDonsHHH: CC C% 4!7

3 months 1 #ear 2 #ears

Follow up

• Early follow up – imaging not recommended unless

complication (bleeding..) suspected

• Late follow up - no consensus on chosen modality

– Comparation to preoperative imaging – Lack of enhancement – Decrease in size of the ablative zone – Peripheral enhancement (usualy disappears after 6 months) – Recurrent tumor versus inflammatory changes

• - New baseline after 6 months

Conclusion

• Guidelines
• T1a(b) tumours
• Biopsy
• Pursuing excellence in technique and

understanding of lethal mechanisms

• Learning curve

Thank you for your attention!