Partial Nephrectomy Planning: Partial Nephrectomy Planning: EverybodyEverybody’’s doing it, you can tos doing it, you can to

Brian R. Herts, MDBrian R. Herts, MDAssociate Professor of RadiologyAssociate Professor of Radiology

Head, Abdominal Imaging, Imaging Institute &Head, Abdominal Imaging, Imaging Institute &Staff, The Staff, The GlickmanGlickman Urological and Kidney Inst.Urological and Kidney Inst.

Cleveland ClinicCleveland Clinic

ObjectivesObjectives

•• Review the current recommendations for treating small renal Review the current recommendations for treating small renal tumors and the indications for partial nephrectomy tumors and the indications for partial nephrectomy

•• Review the surgical planning needs for nephron sparing surgeryReview the surgical planning needs for nephron sparing surgery• Learn imaging techniques and tips to provide surgical planning

information

•• Nephron sparing surgery includesNephron sparing surgery includes•• Open and laparoscopic partial nephrectomyOpen and laparoscopic partial nephrectomy•• Laparoscopic and percutaneous ablation techniquesLaparoscopic and percutaneous ablation techniques

RCC FactsRCC Facts……•• 3% of all visceral malignancies3% of all visceral malignancies•• Risk factors Risk factors -- smoking, obesitysmoking, obesity•• 20082008

•• 54,000 new cases54,000 new cases•• 4% bilateral4% bilateral•• 13,000 deaths/yr13,000 deaths/yr•• 33% present with locally advanced or metastatic disease33% present with locally advanced or metastatic disease

•• 1010--yr survival rate (2000) yr survival rate (2000) •• T1 T1 -- 91%, 91%, •• T2 T2 -- 70%70%•• T3a T3a -- 53%53%•• T3b,c T3b,c -- 4242--43%43%

RCC treatmentRCC treatment

•• TreatmentTreatment•• Surgery remains best curative treatment optionSurgery remains best curative treatment option•• Medical therapies and radiation therapy poorMedical therapies and radiation therapy poor

•• IFNIFN--αα, IL2, vaccines all have had limited success, IL2, vaccines all have had limited success•• Response rates < 30%Response rates < 30%

•• Recent advancesRecent advances•• Surgical options have expanded Surgical options have expanded -- NSS, NSS, cryoablationcryoablation, RF, RF•• Cellular receptor targeted therapy for Cellular receptor targeted therapy for metastaticmetastatic diseasedisease

•• VEGVEG--F & PDGFF & PDGF--αα inhibitors showing promiseinhibitors showing promise•• SutentSutent ((sunitinibsunitinib malatemalate) & ) & SorafenibSorafenib

Trend towards MIS and NSSTrend towards MIS and NSS(Part 1: (Part 1: ““EverybodyEverybody’’s doing its doing it””))

•• More institutions and more Urologists are More institutions and more Urologists are performing open and laparoscopic NSSperforming open and laparoscopic NSS

•• More radiologists performing percutaneous NSSMore radiologists performing percutaneous NSS

•• Washington University studyWashington University study•• 19991999--2003 showed an increase in NSS 2003 showed an increase in NSS -- 33/yr to 91/yr33/yr to 91/yr•• Laparoscopic Laparoscopic pNxpNx went from 3% to 56% of all went from 3% to 56% of all pNxpNx

•• BhayaniBhayani et al, Urology 2006;68:732et al, Urology 2006;68:732

CC Urologic Surgical Procedures CC Urologic Surgical Procedures

•• NSS procedures more than doubled in an 8NSS procedures more than doubled in an 8--year periodyear period•• Laparoscopic procedures have had the biggest growthLaparoscopic procedures have had the biggest growth

Cleveland Clinic Glickman Urological Institute data

Revised Staging Criteria 1997 / 2003Revised Staging Criteria 1997 / 2003

•• Tumor (T)Tumor (T)•• T1 T1 ≤≤ 7 cm7 cm, confined to the kidney , confined to the kidney (previously 2.5 cm)(previously 2.5 cm)

•• T1a T1a ≤≤ 4 cm4 cm•• T1b > T1b > 4 cm4 cm

•• T2 > T2 > 7 cm7 cm, confined to the kidney, confined to the kidney•• T3 T3 -- Venous invasion, adrenal or Venous invasion, adrenal or perinephricperinephric fatfat

•• T3a T3a -- adrenal gland, adrenal gland, w/iw/i GerotaGerota’’ss fasciafascia•• T3b T3b -- renal vein / vena cava below diaphragmrenal vein / vena cava below diaphragm•• T3c T3c -- vena cava or wall above diaphragm vena cava or wall above diaphragm (former T4b)(former T4b)

•• T4 T4 -- Beyond Beyond GerotaGerota’’ss fascia fascia (no a or b)(no a or b)

Note: changes in 1997 highlighted in yellowNote: changes in 1997 highlighted in yellow

Renal central sinus invasion and urothelial invasion

•• Occurs in less than 10% of patients butOccurs in less than 10% of patients but•• Invasion of the central sinus fat may have significant Invasion of the central sinus fat may have significant

prognostic indicationsprognostic indications•• similar to extension outside the renal capsule similar to extension outside the renal capsule

•• Patients with T2 tumors with urothelial invasion did Patients with T2 tumors with urothelial invasion did worse than those without urothelial invasionworse than those without urothelial invasion

•• suggested as an added criterion for stagingsuggested as an added criterion for staging

•• Patients with Patients with ‘‘centralcentral’’ tumors more likely to need tumors more likely to need collecting system repair at surgerycollecting system repair at surgery

““ImperativeImperative”” indications for NSS for Renal Neoplasmsindications for NSS for Renal Neoplasms

•• Bilateral renal tumors (approx 4% at diagnosis)Bilateral renal tumors (approx 4% at diagnosis)•• Solitary kidney (prior Nx, renal agenesis)Solitary kidney (prior Nx, renal agenesis)•• Functionally solitary kidney Functionally solitary kidney

•• chronic obstruction, infection, renal vascular diseasechronic obstruction, infection, renal vascular disease

•• Underlying disease predisposing to CKDUnderlying disease predisposing to CKD•• Calculus, infection, diabetes mellitus, SLE, HTNCalculus, infection, diabetes mellitus, SLE, HTN

•• Why? Why? -- avoid dialysis whenever possibleavoid dialysis whenever possible……..

Treatment recommendations for cT1 tumorsTreatment recommendations for cT1 tumors

•• Open partial nephrectomy is considered the standard of care Open partial nephrectomy is considered the standard of care by the AUA for clinical T1 renal mass by the AUA for clinical T1 renal mass -- particularly if renal particularly if renal function is compromised or potentially compromised function is compromised or potentially compromised regardless of the presence of a normal regardless of the presence of a normal contralateralcontralateral kidneykidney

•• Despite dissemination of Despite dissemination of pNxpNx techniques, radical techniques, radical nephrectomy remains over utilized.nephrectomy remains over utilized.

•• Estimated that less than 50% of T1 tumors are treated by partialEstimated that less than 50% of T1 tumors are treated by partialnephrectomynephrectomy

•• …… therefore the number of partial therefore the number of partial nephrectomiesnephrectomies for small for small renal tumors will be increasing renal tumors will be increasing ……

Why nephron sparing surgery?Why nephron sparing surgery?

#1 #1 -- Success with imperative indicationsSuccess with imperative indications

#2 #2 -- Increase in incidentally detected renal massesIncrease in incidentally detected renal masses

#3 #3 -- More benign tumors are resected as smaller More benign tumors are resected as smaller tumors discovered and treatedtumors discovered and treated

#4 #4 -- Better outcomes for patients, particularly with Better outcomes for patients, particularly with better longbetter long--term renal functionterm renal function

Reason #1 Reason #1 -- Good treatment successGood treatment success

•• First and foremost this is a cancer operationFirst and foremost this is a cancer operation

No. of No. of patients in patients in

study*study*

Recurrence Recurrence raterate

Local Local tumor tumor

survivalsurvival121121 4.1%4.1% 90%90%185185 5.9%5.9% 89%89%146146 2.7%2.7% 93%93%

485485146146

3.2%3.2%2.7%2.7%

92%92%93%93%

*Table adapted from Novick AC. Ann Rev Med 2002

Reason #2 Reason #2 -- the incidental renal massthe incidental renal mass

•• Approximately 60Approximately 60--65% of RCC are incidentally detected65% of RCC are incidentally detected•• Classic triad of fever, flank pain, Classic triad of fever, flank pain, hematuriahematuria is is rarerare

•• Abdominal imaging trends (all modalities) Abdominal imaging trends (all modalities) •• 1996 1996 -- 451.8 per 1000 Medicare patients451.8 per 1000 Medicare patients•• 2005 2005 -- 564.5 per 1000 Medicare patients564.5 per 1000 Medicare patients•• …… 25% increase25% increase

•• CT/CTA: CT/CTA: +141% increase+141% increase 99.4 to 239.3/1000 99.4 to 239.3/1000 •• MR/MRA: MR/MRA: +365% increase+365% increase 2 to 9.3/10002 to 9.3/1000

Reason #2 Reason #2 -- the incidental renal massthe incidental renal mass

•• More incidental renal masses are low stage More incidental renal masses are low stage •• 64% 64% -- 78% incidental RCC are stage T1 or T278% incidental RCC are stage T1 or T2•• 36% 36% -- 57% symptomatic RCC are stage T1 or T257% symptomatic RCC are stage T1 or T2

•• Incidental tumors are smaller Incidental tumors are smaller •• 5.9 cm v. 7.5 5.9 cm v. 7.5 -- 8.7 cm8.7 cm

•• Smaller tumors are less aggressive Smaller tumors are less aggressive •• ((RemziRemzi et al J et al J UrolUrol 2006)2006)

•• 4/168 (2.4%) of 3 cm or less v. 10/119 (8.4%) of 4/168 (2.4%) of 3 cm or less v. 10/119 (8.4%) of 3.13.1--4 cm with distant metastases4 cm with distant metastases

…… therefore they are more suitable for NSS!therefore they are more suitable for NSS!

Reason #3 Reason #3 -- Benign Findings at Surgery Benign Findings at Surgery

•• Frank et al J Frank et al J UrolUrol 2003 2003 –– 2935 tumors in 2770 adults all 2935 tumors in 2770 adults all specimensspecimens

•• KutikovKutikov et al et al UrolUrol 2006 2006 –– 143 tumors in 143 adults with 143 tumors in 143 adults with suspected RCCsuspected RCC

< 1.0 cm< 1.0 cm 11--1.9 cm1.9 cm 22--2.9 cm2.9 cm 33--3.9 cm3.9 cm 44--4.9 cm4.9 cm 55--5.9 cm5.9 cm 66--6.9 cm6.9 cm

% benign% benign 46.3%46.3% 22.4%22.4% 22.0%22.0% 19.9%19.9% 9.9%9.9% 13%13% 4.5%4.5%

% malignant% malignant 53.8%53.8% 77.7%77.7% 78.0%78.0% 80.1%80.1% 90.1%90.1% 87.0%87.0% 95.5%95.5%

< 2.0 cm< 2.0 cm 2.02.0--4.0 cm4.0 cm > 4.0 cm> 4.0 cm

% benign% benign

% malignant% malignant

16.5%16.5%15.9%15.9%

84.1%84.1% 83.5%83.5%

14.3%14.3%

85.7%85.7%

Reason #4 Reason #4 -- OutcomesOutcomes

•• Radical versus partial nephrectomyRadical versus partial nephrectomy•• 50% more 50% more RadRad NxNx pts with pts with proteinuriaproteinuria (55% v. 34.5%)(55% v. 34.5%)•• Nearly 2x as many Nearly 2x as many RadRad NX pts with CKD (22.4% v. 11.6%)NX pts with CKD (22.4% v. 11.6%)

•• 33--yr probability of CKDyr probability of CKD•• 65% after 65% after RNxRNx v. 20% after v. 20% after PNxPNx

•• Survival in patients with pT1a tumorsSurvival in patients with pT1a tumors•• Radical Radical NxNx (290) versus partial (290) versus partial NxNx (358)(358)•• Higher relative risk of death w/ Higher relative risk of death w/ RadRad NxNx -- 2.16 (age < 65)2.16 (age < 65)

Planning for NSS Planning for NSS (Part 2: (Part 2: ““You can do it toYou can do it to””))

•• ComplicationsComplications•• HemorrhageHemorrhage•• Renal infarction / lossRenal infarction / loss•• Urinary leak or fistulaUrinary leak or fistula•• AbscessAbscess

•• RatesRates•• Lap Lap PNxPNx -- 9%9%•• Open Open PNxPNx -- 6.3%6.3%•• RFA RFA -- 6%6%•• Lap Lap RNxRNx -- 3.4%3.4%•• Open Open RNxRNx -- 1.3%1.3%

Planning info for NSS Planning info for NSS -- avoid complications!avoid complications!

•• Renal arterial and venous anatomyRenal arterial and venous anatomy•• Vena Cava variantsVena Cava variants•• Kidney positionKidney position•• Tumor location and depthTumor location and depth•• Collecting system involvementCollecting system involvement•• Number, course of Number, course of ureter(sureter(s))

ThreeThree--phase MDCT scan phase MDCT scan

•• 1) Unenhanced 1) Unenhanced •• 20 cc timing bolus (scan q1 sec from 2020 cc timing bolus (scan q1 sec from 20--45 s) or contrast 45 s) or contrast

preloadpreload…… wait 2 minutes to wait 2 minutes to opacifyopacify the collecting systemthe collecting system ……

•• 2) Vascular or corticomedullary phase2) Vascular or corticomedullary phase•• Timing bolus or automated tracking (Timing bolus or automated tracking (abdabd aorta trigger)aorta trigger)•• Add + 5 seconds or autoAdd + 5 seconds or auto--trackingtracking•• Aim for both arterial and venous enhancementAim for both arterial and venous enhancement

•• 3) Nephrographic or parenchymal phase3) Nephrographic or parenchymal phase•• 120 seconds from start of contrast injection120 seconds from start of contrast injection

•• Earlier for younger patients, later for older, fast scansEarlier for younger patients, later for older, fast scans•• Ensures nephrographic phaseEnsures nephrographic phase

ThreeThree--phase renal CTphase renal CT

•• 16 slice / detector MDCT & up16 slice / detector MDCT & up•• 0.6, 0.625 or 0.75 mm slice collimation0.6, 0.625 or 0.75 mm slice collimation•• 33--5 mm slice thickness / 3 mm interval for diagnostic interpretati5 mm slice thickness / 3 mm interval for diagnostic interpretationon•• 1 mm slice thickness x 0.8 mm for MPR, VR reconstructions1 mm slice thickness x 0.8 mm for MPR, VR reconstructions

•• Obese patientsObese patients•• Use thicker collimator Use thicker collimator -- 1.2, 1.25, 1.51.2, 1.25, 1.5

•• We use dose modulation algorithms (both We use dose modulation algorithms (both xx--yy and z directions)and z directions)

NPCMPNC

MR protocolsMR protocols

•• Coils 1.5 T & 3T phased array body coilsCoils 1.5 T & 3T phased array body coils•• Pre contrast Pre contrast ––

•• Axial T1 in/out Axial T1 in/out -- 55--6 mm slices.6 mm slices.

•• Axial & Coronal HASTE Axial & Coronal HASTE -- No fat sat No fat sat -- 55--6mm slices6mm slices•• Axial VIBE Axial VIBE –– 1.5 mm effective slice thickness1.5 mm effective slice thickness•• Coronal 3D FLASH Coronal 3D FLASH -- Try to get effective thickness 2mmTry to get effective thickness 2mm

MR protocols (cont.)MR protocols (cont.)•• Post contrast Post contrast ––

•• Timing Run Timing Run -- axial thru kidneys axial thru kidneys ––contrast at 2cc/sec followed by 20 cc contrast at 2cc/sec followed by 20 cc saline at 2cc/secsaline at 2cc/sec

•• Standard timing formulaStandard timing formula•• TP + injectTP + inject--time/2 time/2 –– timetime--toto--centercenter

•• Coronal 3D FLASHCoronal 3D FLASH•• Axial & coronal Axial & coronal VIBEsVIBEs

•• 0, 30, 60, 90, 180 0, 30, 60, 90, 180 secssecs•• SubtractionSubtraction

Image creationImage creation

•• MIPsMIPs and and MPRsMPRs•• Coronal oblique Coronal oblique MIPsMIPs of arterial system of arterial system ≈≈ aortaaorta•• MPRsMPRs oblique coronal and oblique coronal and sagittalsagittal MPRsMPRs ≈≈ long axis of the long axis of the

kidneykidney

Image creationImage creation

•• Volume rendering Volume rendering •• Opacity settings to preferenceOpacity settings to preference

•• Mine Mine –– approx 50%approx 50%•• Or use presets Or use presets ……

Tumor positionTumor position•• Four renal segments, based on vascular territoriesFour renal segments, based on vascular territories

apicalanterior

basilar

posterior

Tumor depth of extension Tumor depth of extension -- terminologyterminology

•• CentralCentral –– extends into the central sinus fat or extends into the central sinus fat or abuts the central sinusabuts the central sinus

•• Higher likelihood of collecting system Higher likelihood of collecting system ““entryentry””

•• PeripheralPeripheral –– no central extensionno central extension•• Surgically simplerSurgically simpler

•• ExophyticExophytic –– identifiable on surfaceidentifiable on surface•• IntrarenalIntrarenal –– may require IOUSmay require IOUS

Anterior, central, exophyticAnterior, central, exophytic

axial

MPRVR

Posterior, central, exophyticPosterior, central, exophytic

Apical, peripheral, exophyticApical, peripheral, exophytic

Basilar, exophytic, centralBasilar, exophytic, central

Central, Central, intrarenalintrarenal

Tumor positionTumor position

Arterial anatomyArterial anatomy

Venous anatomyVenous anatomy

Circumaortic left renal veinRetroaortic left renal vein

BillingBilling

•• 2007 reimbursement rates (from the web)2007 reimbursement rates (from the web)

WhatWhat’’s next? Segmentation and tumor volumes next? Segmentation and tumor volume

•• Studies looking at relationship of tumor and renal Studies looking at relationship of tumor and renal parenchymal volume to NSS and outcomeparenchymal volume to NSS and outcome

•• Segmentation results from software Segmentation results from software •• VolumeVolume•• Mean density & Mean density & std. dev.std. dev.•• RecistRecist diametersdiameters

SummarySummary

•• Open Open pNxpNx is now recommended treatment for small renal massis now recommended treatment for small renal mass•• More Urologists will be doing more NSS for SRMMore Urologists will be doing more NSS for SRM

•• Least experienced will need the most operative guidance!Least experienced will need the most operative guidance!

•• Images to provideImages to provide•• Arterial / Venous anatomyArterial / Venous anatomy

•• Number, location, branchingNumber, location, branching•• AnomaliesAnomalies

•• Tumor Tumor •• Location anterior/posterior/apical/basilarLocation anterior/posterior/apical/basilar•• Location Location -- exophyticexophytic / depth / involvement of calices/ depth / involvement of calices

•• Ureter(sUreter(s))

•• Bill as 3D when requested by the surgeonBill as 3D when requested by the surgeon

ReferencesReferences

•• RemziRemzi M, et al. J M, et al. J UrolUrol 2006;176:8962006;176:896--899899•• Frank I, et al. J Frank I, et al. J UrolUrol 2003;170:22172003;170:2217--2020•• KutikovKutikov A, et al A, et al UrolUrol 2006;68:7372006;68:737--4040•• BhayaniBhayani et al. Urology 2006;68:732et al. Urology 2006;68:732• Novick AC. Ann Rev Med 2002;53:393-407• Levin DC et al, J Am Coll Radiol 2008;5:744-747•• Lau et al, Mayo Clinic Proceedings, 2000;75:1236Lau et al, Mayo Clinic Proceedings, 2000;75:1236--12421242•• Thompson et al J Thompson et al J UrolUrol 2008;179:4682008;179:468--473473