Approach to the Incidental Cystic Renal Mass Renal Masse… · Cystic Renal Mass Harvard Medical...
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Page 1 Stuart G. Silverman, MD, FACR Stuart G. Silverman, MD, FACR Professor of Radiology Professor of Radiology Har ard Medical School Har ard Medical School Approach to the Incidental Approach to the Incidental Cystic Renal Mass Cystic Renal Mass Harvard Medical School Harvard Medical School Director, Abdominal Imaging Director, Abdominal Imaging and Intervention and Intervention Brigham and Women’s Hospital Brigham and Women’s Hospital Boston, MA Boston, MA Stuart G. Silverman, MD, FACR Stuart G. Silverman, MD, FACR Approach to the Incidental Approach to the Incidental Cystic Renal Mass Cystic Renal Mass Disclosure of financial relationship with Disclosure of financial relationship with relevant commercial interest relevant commercial interest relevant commercial interest relevant commercial interest Lippincott, Williams, and Wilkins Lippincott, Williams, and Wilkins Philadelphia, PA Philadelphia, PA – Book Royalties Book Royalties Cancer Incidence Cancer Incidence Kidney and renal pelvis Kidney and renal pelvis All sites All sites Not solely due to imaging Not solely due to imaging ?Tobacco use, obesity… ?Tobacco use, obesity… http:// www.seer.cancer.gov http:// www.seer.cancer.gov Diagnostic Problem Diagnostic Problem • More than half of pts > 50 years More than half of pts > 50 years of age have at least 1 mass of age have at least 1 mass • Most are seen by radiologists Most are seen by radiologists using cross using cross-sectional imaging sectional imaging • Most are benign Most are benign • RCC and benign lesions look RCC and benign lesions look alike alike Outline Outline • Techniques Techniques • Differential diagnosis Differential diagnosis • Cystic masses (after Cystic masses (after • Cystic masses (after Cystic masses (after Bosniak) Bosniak) • The JACR white paper The JACR white paper • Uncharacterized masses Uncharacterized masses BWH Renal Mass CT Protocol BWH Renal Mass CT Protocol 64 Channel MDCT with 3 phases 64 Channel MDCT with 3 phases Contrast Material (80cc) Contrast Material (80cc) Unenhanced Unenhanced Nephrographic Nephrographic Excretory Excretory Range Range Kidneys Kidneys Kidneys Kidneys Abd only Abd only Delay Delay -- -- 100 s 100 s 8 min 8 min Collimation 1.2 mm 1.2 mm Collimation 1.2 mm 1.2 mm 0.6 mm 0.6 mm Axial Recon/Incr 3/1.5 3/1.5 Axial Recon/Incr 3/1.5 3/1.5 3/3 3/3 Post Processing Post Processing -- -- -- -- Coronal Coronal Iodinated contrast material (370 mgI/ml); 0.5 s rotation Iodinated contrast material (370 mgI/ml); 0.5 s rotation time; AEC w/ quality reference 200 mAs, 120 kVp time; AEC w/ quality reference 200 mAs, 120 kVp
Transcript of Approach to the Incidental Cystic Renal Mass Renal Masse… · Cystic Renal Mass Harvard Medical...
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Stuart G. Silverman, MD, FACRStuart G. Silverman, MD, FACRProfessor of RadiologyProfessor of RadiologyHar ard Medical SchoolHar ard Medical School
Approach to the Incidental Approach to the Incidental Cystic Renal MassCystic Renal Mass
Harvard Medical School Harvard Medical School Director, Abdominal Imaging Director, Abdominal Imaging
and Interventionand InterventionBrigham and Women’s HospitalBrigham and Women’s Hospital
Boston, MABoston, MA
Stuart G. Silverman, MD, FACRStuart G. Silverman, MD, FACR
Approach to the Incidental Approach to the Incidental Cystic Renal MassCystic Renal Mass
Disclosure of financial relationship with Disclosure of financial relationship with relevant commercial interestrelevant commercial interestrelevant commercial interestrelevant commercial interest
Lippincott, Williams, and Wilkins Lippincott, Williams, and Wilkins Philadelphia, PA Philadelphia, PA –– Book RoyaltiesBook Royalties
Cancer IncidenceCancer Incidence
Kidney and renal pelvisKidney and renal pelvis
All sitesAll sites
Not solely due to imagingNot solely due to imaging
?Tobacco use, obesity… ?Tobacco use, obesity…
http:// www.seer.cancer.govhttp:// www.seer.cancer.gov
Diagnostic ProblemDiagnostic Problem•• More than half of pts > 50 years More than half of pts > 50 years
of age have at least 1 massof age have at least 1 mass
•• Most are seen by radiologists Most are seen by radiologists y gy gusing crossusing cross--sectional imagingsectional imaging
•• Most are benignMost are benign
•• RCC and benign lesions look RCC and benign lesions look alikealike
OutlineOutline•• TechniquesTechniques
•• Differential diagnosisDifferential diagnosis
•• Cystic masses (afterCystic masses (after•• Cystic masses (after Cystic masses (after Bosniak)Bosniak)
•• The JACR white paperThe JACR white paper
•• Uncharacterized massesUncharacterized masses
BWH Renal Mass CT ProtocolBWH Renal Mass CT Protocol
64 Channel MDCT with 3 phases64 Channel MDCT with 3 phasesContrast Material (80cc)Contrast Material (80cc)
UnenhancedUnenhanced NephrographicNephrographic ExcretoryExcretoryRangeRange KidneysKidneys KidneysKidneys Abd onlyAbd onlyDelay Delay ---- 100 s 100 s 8 min8 minyyCollimation 1.2 mm 1.2 mm Collimation 1.2 mm 1.2 mm 0.6 mm0.6 mmAxial Recon/Incr 3/1.5 3/1.5 Axial Recon/Incr 3/1.5 3/1.5 3/33/3Post Processing Post Processing ---- ---- CoronalCoronal
Iodinated contrast material (370 mgI/ml); 0.5 s rotation Iodinated contrast material (370 mgI/ml); 0.5 s rotation time; AEC w/ quality reference 200 mAs, 120 kVptime; AEC w/ quality reference 200 mAs, 120 kVp
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What is too small to characterize?What is too small to characterize?
TSTC Definition relates to technique!TSTC Definition relates to technique!
Lesion diameter < 2x section thickness Lesion diameter < 2x section thickness
Section thickness Section thickness << ½ lesion diameter½ lesion diameter
Section thickness Section thickness > ½ lesion diameter> ½ lesion diameter
5 mm x 5 mm5 mm x 5 mm 3 mm x 1.5 mm3 mm x 1.5 mm
Renal Masses Renal Masses –– Benefit of Thin ReconstructionsBenefit of Thin Reconstructions
Reconstructing 2.5 mm collimated data at 3 mm Reconstructing 2.5 mm collimated data at 3 mm thick sections minimizes volume averagingthick sections minimizes volume averaging
10 mm = Thk x 210 mm = Thk x 2 4.5 mm = (Thk x 2) 4.5 mm = (Thk x 2) –– 1.51.5
Renal Masses with MDCTRenal Masses with MDCT
•• Of 44 masses Of 44 masses between 5 between 5 and 10 mmand 10 mm, 13 , 13 (30%)(30%) were were characterized as cysts on characterized as cysts on
Jinzaki et al, AJR 2004Jinzaki et al, AJR 2004
yy5/5 mm images, whereas 39 5/5 mm images, whereas 39 (89%)(89%) were characterized as were characterized as cysts on 3/1.5 imagescysts on 3/1.5 images
Cystic Renal Mass < 1cmCystic Renal Mass < 1cm
“3 mm cystic renal mass “3 mm cystic renal mass that is too small to that is too small to
Radiology Report…Radiology Report…
diagnose definitively; it diagnose definitively; it is statistically likely to be is statistically likely to be a benign simple cyst.”a benign simple cyst.”
Bosniak and Rofsky, Radiology 1996Bosniak and Rofsky, Radiology 1996
Silverman SG et al, Radiology 2008Silverman SG et al, Radiology 2008
Differential DiagnosisDifferential Diagnosis
PseudotumorsPseudotumors
Vascular abnormalityVascular abnormality
InflammatoryInflammatory
Consider… Consider…
InflammatoryInflammatory
TraumaticTraumatic
CystCyst--likelike
SolidSolid
BeforeBeforeconsidering… considering…
Cystic Renal MassesCystic Renal Masses(after Bosniak)(after Bosniak)
CatCat TermTerm Prob % RemarkProb % Remark
II SimpleSimple 00 proven proven
IIII ComplicatedComplicated @0@0 variablevariable
Aronson Urol Rad 1991Aronson Urol Rad 1991
IIII ComplicatedComplicated @0@0 variablevariable
IIFIIF IndeterminateIndeterminate ?? IsraelIsrael
IIIIII IndeterminateIndeterminate 5050 Aronson Aronson
IVIV Solid FeaturesSolid Features >95>95 CurryCurry
Curry AJR 1991Curry AJR 1991
Israel AJR 2003Israel AJR 2003
Israel and Bosniak Radiology 2005Israel and Bosniak Radiology 2005
Bosniak MA Radiology 1991Bosniak MA Radiology 1991
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Category I CystCategory I Cyst
•• WellWell--marginatedmarginated
•• Water attenuationWater attenuation(0(0--20 HU)20 HU)
•• NonNon--enhancingenhancing
•• HairHair--line thin wallline thin wall
Benign simple cystBenign simple cyst
IgnoreIgnore
Category I CystCategory I Cyst
Benign simple CystBenign simple Cyst
Perceptible wall isPerceptible wall is
acceptable!acceptable!
•• Thin and few septaThin and few septa
•• Small, borderSmall, border--formingformingcalcificationcalcification
Category II CystCategory II Cyst
Benign complicated cystBenign complicated cyst
IgnoreIgnore
Category II CystCategory II CystSmall (Small (<< 3cm), homogeneously hyperdense, 3cm), homogeneously hyperdense, typically 40typically 40--90 HU, and nonenhancing90 HU, and nonenhancing
87 HU87 HU 90 HU90 HU
Hyperdense cystHyperdense cyst
IgnoreIgnore
Category IIF CystCategory IIF Cyst•• Multiple (more than a few), thin Multiple (more than a few), thin or minimally thickened septa, or minimally thickened septa, with perceived enhancementwith perceived enhancement
•• Thick / nodular calcificationThick / nodular calcification
Benign multilocular cystBenign multilocular cyst
•• Large (>3 cm) hyperdense cystLarge (>3 cm) hyperdense cyst
Follow at 6, 12, and q12 mo to 5 yrsFollow at 6, 12, and q12 mo to 5 yrs
Israel and Bosniak AJR 2003Israel and Bosniak AJR 2003Interval and duration may be variedInterval and duration may be varied
Renal Mass MR ProtocolRenal Mass MR Protocol•• T1T1--w SPGR or FSEw SPGR or FSE•• T2T2--w FRFSE or SSFSEw FRFSE or SSFSE•• Chemical Shift (In/OOP)Chemical Shift (In/OOP)•• T1T1--w SPGR, Fat w SPGR, Fat
suppressed, pre + post suppressed, pre + post contrast materialcontrast material
•• Subtraction imagesSubtraction images
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Cystic Renal Masses Cystic Renal Masses ––Bosniak applied to MRIBosniak applied to MRI
•• Of 69 cystic masses, MR was used to Of 69 cystic masses, MR was used to upgrade 7 masses: II to IIF in 2, IIF to III in 3, upgrade 7 masses: II to IIF in 2, IIF to III in 3, and III to IV in 2.and III to IV in 2.
MRI most helpful in indeterminate lesionsMRI most helpful in indeterminate lesions::
ALL Category IIF and III lesionsALL Category IIF and III lesions
Confirm minimal (<1 cm) cystic masses as Confirm minimal (<1 cm) cystic masses as simple…simple…
Israel and Bosniak Radiology 2004Israel and Bosniak Radiology 2004
Size and Growth…cysticSize and Growth…cystic•• Growth is not necessarily Growth is not necessarily predictive (and not part of the predictive (and not part of the Bosniak classification) Bosniak classification) –– Benign Benign cysts grow; cancerous ones may cysts grow; cancerous ones may
littl if t lllittl if t llgrow little, if at all.grow little, if at all.
•• The smaller the mass, the more The smaller the mass, the more likely it is benign.likely it is benign.
Silverman SG et al, Radiology 2008Silverman SG et al, Radiology 2008
Category III CystCategory III Cyst•• Multiple and thick, Multiple and thick, enhancing septa; thick wallenhancing septa; thick wall
•• Thick / nodular Thick / nodular calcificationcalcification
Cystic RCCCystic RCC
SurgerySurgery
calcificationcalcificationT2T2
PostPost
Category IV CystCategory IV Cyst
•• Nodular /softNodular /soft--tissue tissue enhancementenhancement
•• Particularly when Particularly when
Cystic RCCCystic RCC
SurgerySurgery
apartapart from wall from wall
pre postpre post50H50H 70H70H
Enhancement at CTEnhancement at CT
•• Unequivocal Unequivocal >> 2020
•• EquivocalEquivocal 1010 -- 2020EquivocalEquivocal 10 10 2020
•• NoneNone < 10 < 10
Note S.D.Note S.D.
Enhancement at MRIEnhancement at MRI
•• Unequivocal Unequivocal >> 20 20 %%
•• EquivocalEquivocal 1515 –– 1919 %%EquivocalEquivocal 15 15 19 19 %%
•• NoneNone < 15 < 15 %%% = SI Change / Native SI% = SI Change / Native SI
Ho VB Radiology 2002Ho VB Radiology 2002
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Management RecommendationsManagement RecommendationsIncidental Cystic Renal MassIncidental Cystic Renal Mass
CatCat TermTerm Gen Pop’n Gen Pop’n CoCo--morbidmorbid
II Simple, benignSimple, benign IgnoreIgnore Ignore Ignore
IIII Complic, benignComplic, benign IgnoreIgnore IgnoreIgnore
When a mass smaller than 1 cm has the When a mass smaller than 1 cm has the appearance of a simple cyst, further workappearance of a simple cyst, further work--up up is not likely to yield useful information.is not likely to yield useful information.
IIFIIF Probably benignProbably benign ObserveObserve Obs/IgnObs/Ign
IIIIII IndeterminateIndeterminate SurgerySurgery Surg/Obs Surg/Obs
IVIV MalignantMalignant SurgerySurgery Surg/ObsSurg/Obs
Silverman SG et al, Radiology 2008 Silverman SG et al, Radiology 2008
Management flowchart… Management flowchart…
JACR 2010 JACR 2010
Management flowchart… Management flowchart…
JACR 2010 JACR 2010
Management flowchart… Management flowchart…
JACR 2010 JACR 2010
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Management flowchart… Management flowchart…
Berland LL et al, JACR 2010 Berland LL et al, JACR 2010
‘Complex’ on US‘Complex’ on US•• Use US to diagnose simple cystsUse US to diagnose simple cysts
•• If not simple, often ‘complex’If not simple, often ‘complex’
•• Renal Mass protocol CT/MRIRenal Mass protocol CT/MRIpp
•• Use of Doppler and the Use of Doppler and the implementation of FDAimplementation of FDA--approved approved contrast agents may allow more contrast agents may allow more cystic masses to be fully diagnosed.cystic masses to be fully diagnosed.
Uncharacterized at NCCTUncharacterized at NCCTCan we ignore these masses?Can we ignore these masses?
87 HU87 HU
Probably… (if >70HU)Probably… (if >70HU)Jonisch et al Radiology 2007Jonisch et al Radiology 2007
Probably… (if <20HU)Probably… (if <20HU)O’Connor et al AJR 2011O’Connor et al AJR 2011
10 HU10 HU
Uncharacterized MassUncharacterized Mass
Uncharacterized at NCCT…Uncharacterized at NCCT…
•• 3,001 pts, mean 57 yrs, 1666 F; mean f/u 3.3 yrs3,001 pts, mean 57 yrs, 1666 F; mean f/u 3.3 yrs
•• 433 (14.4%) w/ masses 433 (14.4%) w/ masses >> 1 cm1 cm
•• Mean 2.5 cm, simpleMean 2.5 cm, simple--appearing (<20H) or appearing (<20H) or hyperdense (>70H) except…hyperdense (>70H) except…
Data from Low Dose Screening CTC…Data from Low Dose Screening CTC…
•• 53 (12.2%) 2053 (12.2%) 20--70H; 15 (3.5%) Ca70H; 15 (3.5%) Ca2+2+; 5 (1.2%) septa; 5 (1.2%) septa
•• Four RCCs, all 20Four RCCs, all 20--70 HU70 HU
•• None of the simpleNone of the simple--appearing or hyperdense (>70H) appearing or hyperdense (>70H) masses was RCCmasses was RCC
O’Connor et al AJR 2011O’Connor et al AJR 2011
How de we report them?How de we report them?
“It may be appropriate to consider simple“It may be appropriate to consider simple--appearing cysts benign on unenhanced CT.”appearing cysts benign on unenhanced CT.”
SimpleSimple--appearing cyst on unenhanced CTappearing cyst on unenhanced CT
Radiology Report…Radiology Report…
“cystic renal mass “cystic renal mass statistically likely benign”statistically likely benign”
Berland et al JACR 2010Berland et al JACR 2010
How de we report them?How de we report them?
So long as the mass is small (So long as the mass is small (<< 3cm) 3cm) homogeneously hyperdense, and > 70 HUhomogeneously hyperdense, and > 70 HU
Hyperdense mass on unenhanced CTHyperdense mass on unenhanced CT
Radiology Report…Radiology Report…
“Hyperdense renal mass. “Hyperdense renal mass. statistically likely benign statistically likely benign proteinaceous cyst”proteinaceous cyst”
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Uncharacterized at NCCT…Uncharacterized at NCCT…Data from a review of RCCs…Data from a review of RCCs…
• All 193 RCC had some areas of 20-70 HU and were
heterogeneous except for 9% which were
homogeneous and measured 20-70 HU
Pooler et al AJR 2012Pooler et al AJR 2012
Of 193 RCCS, none was homogeneous and
< 20 HU or > 70 HU
How de we report them?How de we report them?
With any areas measuring 20With any areas measuring 20--70HU….70HU….
Heterogeneous mass on unenhanced CTHeterogeneous mass on unenhanced CT
Radiology Report…Radiology Report…
“Heterogeneous that could represent a “Heterogeneous that could represent a RCC, or a hemorrhagic or complicated RCC, or a hemorrhagic or complicated cyst. Renal mass protocol CT or MRI cyst. Renal mass protocol CT or MRI recommended.”recommended.”
