Jane L. Messina, MD September 16, 2017

Jane L., Messina, MD September 16, 2017

MELANOMAVERSUSNEVUS:STRATEGIESFORTHEDIFFICULT

DECISION

Conflicts

•   IserveasaconsultanttoCastleBiosciences

Objec.ves

•   Reviewclassicfeaturesofmelanoma•   AJCCupdate•   Discusscommonlyencountereddiagnos<cdilemmas

Thereal thing

Asymmetry

Poorcircumscrip<on

Confluence,epidermaleffacement

Sheet-likegrowth,atypia,mitoses

AJCC8 th edi.onupdate (effec.ve

1/1/2018)

•   Primarytumorstaging:–   Breslowdepthtonearest0.1mm–   Ulcera<on(widthmeasured!!)–  Microsatellites:“microscopictumorfociwithindermisorsubQadjacenttobutdiscon<nuousfromprimary”;nominimumsizeordistance

–   Repor<ngofmitoses“recommended”

AJCC8 th edi.onstagingchanges

TX Primarytumorthicknesscannotbeassessed(i.e.cureIagespecimen)

T0 Regressedmelanomaormelanomaofunknownprimary

T1a

T1b

0-0.8mm

>0.8mm-1.0mmorulcera.on

T2a/b 1.1-2.0mmw/orw/oulcera.on

T3a/b 2.1-4.0mmw/orw/oulcera.on

T4a/b >4.0mmw/orw/oulcera.on

N1 N2 N3

A-occult 1 2-3 >4

B-clinical 1 2-3,atleast1clinical+ >4,atleast1clinical+

C-microsatellites 0nodes+

microsatellite

Atleast1node+

microsatellite

Atleast2nodes+

microsatellite

Commonlyencounteredscenarios

•   Lackofcompunc<onatthejunc<on•   Specialsites•   Nevoidmelanoma,dysplas<cnevus,orboth??•   Downanddirtyinthedermis:spindled,pigmented,andugly

•   Spitzoidlesions

Lackofcompunc.onatthe

junc.on

Melan-A

MITF

Melanoma in s i tu!

Immunohistochemistry in sun-damaged

skin

•   S-100–   Polyclonal:crossreactswithpigmentedAK

–  Monoclonal:diminished

sensi.vityinLMandALM

•   HMB-45:patchy/par.alstaining

•   Melan-AandMart-1:overstainingaproblem

•   Sox-10orMITF:ideal

Mart-1

MITF

Quan.fica.onof melanocytes insun-

damagedskin(CSD)-what is normal?

•   Confluence>3melanocytesfoundin16%ofSDSspecimensonH&E,4%onMart-1

•   Deepfollicularmelanocytesin6%,nestedmelanocytesin1BCCspecimen

•   Melanocytedensity:LM>NMSCpa<ents

Barlow,Maize,andLang.DermatolSurg2007;33:199–207Madden,Forman,andElston.JAmAcadDermatol2011;64:548-52.)

*MANOVA

200µ

•  Density:numberofmelanocytes/200µm•  Diameter:modeofnucleardiameterofshortestaxisof3melanocytes•  Densityxdiameter>80is85%sensi<veand100%specificforMIS

AmJDermatopathol2011;33:573–578

Minimaldiagnos.ccriteriaforMIS

(len.gomalignatype)

•   H&EandSox-10/MITFstaining•   Highnumberofmelanocytes:>10per200µm,especiallyif

presentoverabroadfront•   Nuclearenlargement>9µmdiameter/pleomorphism•   Inabsenceofnes<ng,confluenceof>3melanocytes•   Irregulardistribu<onofmelanocytes•   Descentofmelanocytesfardownadnexalstructures•   Irregulardistribu<onofpigment•   Melanocytespresentabovebasallayerinsignificantnumbers

AmJDermatopathology;18(6),December1996,pp560-566

Residual melanomavs melanocy.c

hyperplas ia?

Lookatrequisi<on!“r/oresidualBCC”

Diagnosis:NoresidualBCC(melanocy<chyperplasiaatpriorbiopsysite)

Previouslybiopsiedlesionwasdiscarded

MarkedcytologicatypiaMyriadresult:3.1

Diagnosis:melanomainsitu,recurrent

Lesiondiameter=2mmPa<entage:8

Diagnosis:PagetoidSpitznevus

PagetoidSpitz nevus

•   5-10%ofallSpitznevi•   Largestseries(12):allfemale,extremitypredominant,medianage34years

•   <5mmdiameter•   Nests<1/3overallcellularity;singlecellsconfinedtolower½ofepidermisin75%

•   Molecular/IHCanalysisnotextremelyhelpful

FernandezAP,BillingsSD,BergfeldWF,KoJS,PiliangM.PagetoidSpitznevi:clinicopathologiccharacteriza<onofaseriesof12cases.JCutanPathol2016;43:932–939

Junc.onal melanocy.cneoplasmonthe

leg of a woman

Diagnosis:Junc<onalmelanocy<cnevus(“len<ginous”type)

“Leg-type”nevi

•   Describedonthigh,belowknee,andankle•   “Epithelioidcellmelanocy<cnevus”,“melanocy<cneviofanklewithatypicalfeatures”,“dysplas<cnevioflegofwomen”

•   Small(4-5mm)•   Singlecells=nests•   Lowpagetoidspread

Dona<P,MuscardinL,CotaC,PaneraC,PaolinoG.Themelanocy<cepithelioidcellnevusofthethighofwoman:asimulatorofmelanoma.AmJDermatopathol.2012Dec;34(8):853-5.doi:10.1097/DAD.0b013e31824d4f86.PubMedPMID:22481498.CorasB,LandthalerM,StolzW,VogtT.Dysplas<cmelanocy<cneviofthelowerleg:sex-andsite-specifichistopathology.AmJDermatopathol.2010Aug;32(6):599-602.doi:10.1097/DAD.0b013e3181ce910b.PubMedPMID:20534984.KhalifehI,TaraifS,ReedJA,LazarAF,DiwanAH,PrietoVG.Asubgroupofmelanocy<cnevionthedistallowerextremity(ankle)sharesfeaturesofacralnevi,dysplas<cnevi,andmelanomainsitu:apoten<almisdiagnosisofmelanomainsitu.AmJSurgPathol.2007Jul;31(7):1130-6.PubMedPMID:17592281.

©2012LippincorWilliams&Wilkins,Inc.PublishedbyLippincorWilliams&Wilkins,Inc. 2

FIGURE2

TheMelanocy.cEpithelioidCellNevusoftheThighof

Woman:ASimulatorofMelanoma.

Dona<,Pietro;Muscardin,Luca;Cota,Carlo;Panera,Chiara;Paolino,GiovanniAmericanJournalofDermatopathology.34(8):853-855,December2012.DOI:10.1097/DAD.0b013e31824d4f86

FIGURE2.Intraepidermalmelanocy<cprolifera<onwithepithelioidappearance(hematoxylinandeosinstain,originalmagnifica<onx10).

EverysiteisSPECIALinitsownway

Ahn,C.,Guerra,A.,andSangueza,OP.AmJDermatopathol2016;38:867-881

Acral sk in

•   Len<ginous>nestedgrowth•   Pagetoidspreadin36%(MANIAClesion!)•   Banal,patchydermalcomponent

Genital ia

•   Large(upto1cm)andwellcircumscribed•   Highcellularityofjunc<onalnests•   Bridgingandfibroplasia•   Dermalmito<cac<vityin7%•   LsEtAbackground:epidermaleffacementandsinglecellconfluencepossible

fromSanguezaetal.

GenitalnevuswithLSetA

Ear

•   Poorcircumscrip<on•   Irregularnes<ng,bridging,fibroplasia

•   Cytologicatypialesscommon

fromSanguezaetal.

Scalp

•   Featuresoverlapwithdysplas<cnevi–   Asymmetry,poorcircumscrip<on,irregularnes<ng,bridging,fibrosis,inflamma<on

•   Mostcommonly,butnotexclusively,foundinadolescentsFisherK,MaizeJC,andMaizeJC.JAmAcadDermatol2013;68:466-72.)

F lexura l s i tes

-m i l k l i ne

- an tecub i ta l /pop l i tea l fo s sae

- b reas t

•   Nestsatsides/betweenrete•   Dyscohesivenestsandsinglecells,len<ginousgrowth,pagetoidspread,andadnexalepithelialinvolvement

•   Atypiamildtoabsent•   Umbilicus:fibroplasia•   Breast:atypia,highcellularitymorecommon

Breast nevi

fromSanguezaetal.

Nevoidmelanoma,dysplas.c

nevus,orboth?

Useful immunohistochemicaltools

OR ?

•   Prolifera<onmarkers:Ki-67,phosphohistoneH3

•   Matura<onmarker:HMB-45•   P16

Ki-67:thegood,thebad,andthe

ugly

Melan-A/Ki-67(MelPro) innevoid

melanoma

Nevi:<5%Melanoma:>10%

MelPro in a nevus

PhosphohistoneH3formitoses

•   Compoundnevus:MR0.06/sqmm•   Spitznevus:meanMR0.5mitoses/10HPF(range0-2)orMR0.325/sqmm

•   Melanoma:meanMR24.7(range2-75)

NasrMR,El-ZammarO.AmJDermatopathol.Apr2008;30(2):117-122Phadkeetal.AmJSurgPathol2011;35:656-699Glatzetal.AmJDermatopathol2010Oct;32(7)643-649.

HMB-45staininginnevusversus

nevoidmelanoma

NevusMelanoma

Pixalls•   Bluenevus,DPN,trauma<zednevusexpressHMB-45

•   10%ofmelanomasshowgradientexpression

p16andmal ignant poten.al

AlDhaybiRetalJAmAcadDermatol.Aug2011;65(2):357-363Ohsieetal.JCutanPathol2008;35:433-444

Retainedexpression:favorsbenign

Expressionlostin50-98%ofmelanomas

p16caveats

•   Manymelanomass<llexpressp16,andbenignnevimaynotexpressit

•   Lossofp16stainingdoesnotequatetohomozygousdele<onof9p21–   Itcanbeposi<veevenin9p21deletedlesions(15%)–   Itcanbenega<veinlesionswithheterozygousloss,epigene<csilencing,orevennormal9p21

Gray-SchopferVCetal.BrJCancer2006;95:496-505Yazdanetal.AmJSurgPathol2014;38:638-645.

Nevoidmelanoma

•   a/k/a/minimaldevia<onorsmallcellmelanoma,~3%ofmelanomas

•   Non-uniformcriteria(Spitzoidlesions?)–   55%plaque-like:paralleltheques–   45%polypoid:resemblecompoundnevi–   “pseudomatura<on”:cellsizeshrinks,butnucleusremainssame

–   DEjunc<onmosthelpful–   Deepmitoses

“Amelanocy<cneoplasmcalledanevus,butwith

subsequentdiagnos<cregret”DiwanandLazar,SurgPathClin

2009

DiwanAH,LazarAJ.SurgPatholClin2009Sep;2(3):521-33Idrissetal.JAAD2015Nov;73(5):836-42

Confluenceatjunc<onParallelthequesPseudomatura<onHopefullyamitosisortwo

Dermal melanomavs. pre-exis.ngnevus

Melanoma!

Pre-exis<ngnevus!

37y/omale,backlesion,“r/oatypia”

HMB-45

Sox10

Pagetoid melanocytes in dysplas.cnevi

•   43dysplas<cnevi•   Pagetoidmelanocytesseenin63%ofcasesonIHC,11%onH&E

AmJDermatopathol2014;36:340–343)

Downanddirtyinthe

dermis

63

S-100

P75-NGFR

Sox-10

MiTF negative (usually)

HMB-45 negative

Melan-A negative

Desmoplas.cmelanoma

•   Purevmixed:>or<90%paucicellulardermalgrowth–   Hypercellularcomponentmaybespindleorepithelioid

64Busam et al. Am J Surg Pathol 2004; 28:1518-1525. Pure Mixed

Differen.al diagnosis

•   Scar:Sox-10nega<ve•   DesmoplasIc(Spitz)nevus:p16NOThelpful(strongin75%pureDM)

•   Neurofibroma:“fingerprint”parernCD34posi<vity•   MPNST:S-100andSox-10usuallyweak/patchy,BRAFusuallynega<ve,lossofH3K27me3

65

Neurofibroma DM Desmoplastic nevus

H3K27me3express ion can d is.nguish

betweenMPNSTand desmoplas.c melanoma

•   LossofstainingusingC36B11an<body(CellSignalingTechnology)seenin69%ofMPNST

•   However,insporadicandradia<on-relatedMPNST,absentstainingseenin95%and91%

•   TMAcontaining55desmoplas<cmelanomasallshowedretainedstaining

66Prieto-Granada C et al., Am J Surg Pathol 2016; 49(4): 479-489

Reta ined express ion

of H3K27me3 in

desmoplas.c/

sp ind le ce l l

melanoma

67

Loss of H3K27me3 in MPNSTar is ing in

neurofibroma

68

Feel ingblue

Epithelioidbluenevus

Pigmentedepithelioidmelanocytoma

Animal-typemelanoma

Epithelioidbluenevus•   Carneytriad

•   LossofPRKAR1α

Pigmentedepithelioidmelanocytoma•   Epidermalhyperplasia

•   Perinuclearpigmentclearing•   <<5%prolifera<onrate

•   40%SLN+•   Allcasesnega<vef/uthusfar

Epithel ioid andfus i formbluenevus

•   CSDskin,noCarneytriad,PRKAR1αretained

Yazdan,P.,Haghighat,Z.,Guitart,J.,andGermai,P.AmJSurgPathol2013;37:81–88)

Clonal nevus

Clonal(“invertedtypeA”)nevus

MBAIT(Melanocy<cBAP-1lossassociatedintradermaltumor)

•   LossofnuclearstainingbyBAP1•   Screenforuveal>cutaneousmelanoma,

mesothelioma

Whataboutme????

Incidence(%)

BAP-1lossHRASNTRKALKROS-1BRAFRETUnknown

34%unknown

Van-Engen-vanGrunsvenetal.AmJSurgPathol2010;34:1436-41Wiesneretal.NatCommun2014;5:3116

•  FoundinlesionsacrossSpitzoidspectrum•  Canbeiden<fiedbyimmunohistochemistry•  AssociatedAST’smayhavedis<nc<vehistology•  Conferpossiblesensi<vitytotargetedtherapy

•   Crizo<nib,cabozantanib,vande<nibusedtotreatALKandROS-1+lungtumorsoflungandRET+thyroidtumors

Significanceofkinasefusions

Moffitt 5-tiered nomenclature for melanocytic neoplasms RISKOFMALIGNANCY

1 2 3 4 5

BENIGN ATYPICAL,FAVORBENIGN

UNCERTAINMALIGNANTPOTENTIAL

ATYPICAL,FAVOR

MALIGNANT

MALIGNANT

CATEGORY

B-BLUENEVUSLIKE

C-CONGENITAL

D-DYSPLASTIC

S-SPITZOID

•   CLINICALHISTORYANDAPPEARANCE•   HISTOLOGICANDIMMUNOHISTOCHEMICALFINDINGS

•   MOLECULARTESTINGIFNECESSARY

Putting it all together

S1

BenignSpitz

nevus

S2

Atypical,

favorbenign

S3

Atypical,

uncertain

biologic

poten.al

S4

Atypical,

favor

malignant

S5

Spitzoid

melanoma

HRAS

amplifica.on

11por7pgain

6p25gain

11q13gain

9p21dele.on

orabn.CGH

6q23gain

Customizing treatment

S1

BenignSpitz

nevus

S2

Atypical,

favorbenign

S3

Atypical,

uncertain

biologic

poten.al

S4

Atypical,

favor

malignant

S5

Spitzoid

melanoma

Re-

excision

0.5-1cm

Re-excision1cmwithSLNB

541pa<entswithAST

SLNB303(56%)

+SLN119(39%)

CLND97(82%)

+CLND18(19%)

NoCLND22(18%)

-SLN184(61%)

NoSLNB238(44%)

5(4%)REGIONAL

RECURRENCE11(5%)REGIONAL

RECURRENCE

1DEATH 5(1%)DEATHS

Lallasetal.LancetOncol2014;15:e178–83

•   24studies,2002-2013•   Averageage:24years•   Medianf/u:59.3months

Let’s do the numbers….

Molecular tests for accurate

iden.fica.onof melanoma

•   Fluorescenceinsituhybridiza<on–   Frequentlyusedintheevalua<onofdiagnos<callychallengingmelanocy<cprolifera<ons

•   AtypicalSpitzoidprolifera<ons(AST),atypicalbluenevus-likeprolifera<ons

•   Compara<vegenomichybridiza<on•   MyriadmyPATH

Oldassay6q23CEP66p25,11q13

Fluorescence in s i tu hybr idiza.on-

NeoSITE®melanoma

•   NeogenomicsLaboratories(Ft.Myers,FL):$1500•   Whataboutborderlinelesionssuchasthis?

Sensi<vity:87%Specificity:95%

Newassay8q249p21

94%98%

Unequivocalmelanoma

FISH in histological ly ambiguousSpitzoid

les ions (AST)

Probeset ASTw/o

recurrence

“AST”withpoor

outcome

(melanoma)

TypicalSpitz

OLDsensi<vity 50-100%6,1,4

OLDspecificity 57-91%4,1 75-100%5,1

NEWsensi<vity 50-100%3,2

NEWspecificity 74-87%2,3

1DemarchisEHetal,PediatrDermatol.2014;31(5)561-92Geramietal,AmJSurgPatholFeb20133Tetzlaffetal,AmJSurgPathol.Dec20134Massietal.JAmAcadDermatol2011;64:919-355DikaetalMelResearch2015;25(4):295-3016Vergieretal.ModernPathology2011;24:613-623

Spec ific F ISHabnormal i.es assoc iatedwith

outcome in border l ine les ions (AST)

•   Homozygousdele.onof9p21:predictslocalrecurrenceandonlyfeaturepredic<veofdeath

•   Gainof6p25and/or11q13:predictsSLNinvolvementbutnotrecurrenceordeath

•   Heterozygous9p21loss:significantsen<nelnodeinvolvementbutnospreadbeyondtheregionalnodes

•   6q23(MYB)loss:associatedwithgoodlongtermoutcome

Geramietal,AmJSurgPathol,Feb2013Northetal.AmJSurgPathol2014;38:824-31Raskinetal.AmJSurgPathol2011;35:243-52

Compara.vegenomic hybridiza.on

•   Assesseschromosomalcopynumberchangesacross<ssue,butmissesindividualcellabnormali<es

•   95%ofmelanomasharbornumerouschromosomalgainsandlosses

•   Nevirarelyshowaberra<ons•   ExcepIons:

–   12-26%ofSpitznevi(esp.recurrent)have11por7qgain–   SomeASThaveabnormalCGH(45%,mostcommongainof1p)

•   DoesnotpredictSLNinvolvement•   Prolifera<venodulesincongenitalnevimayhavewholechromosomalgains

Bas<anBCetal.JInvestDermatol.1999;113:1065–1069.Bas<anBCetal.AmJPathol.2003;163:1765–1770Raskinetal.AmJSurgPathol2011;35:243–252

Compara.vegenomic hybridiza.on

•   Mostcommonlyusedtodis<nguishpediatricatypicalSpitztumorfrommelanoma

•   Notwidelyavailable,insurancecoveragevaries•   Typicalout-of-pocketcost$2500

MyriadMyPath-diagnos.caid for

equivocal les ions

•   23-geneexpressionsignaturethatcanhelpdifferen<atenevifrommelanoma-u<lizes5recutslidesfromparaffinblock

•   Trainingandvalida<oncohortsof900+unequivocalmelanomaandnevi:sensi<vity90%specificity91%

•   Currentlyundergoinglarge-scaletes<ngofclinicalu<litywithmelEvalPRO

Clarkeetal.JCutanPathol2015;42:244-252

Superficial

spreading>nodular>len.go

maligna

Compound

anddermal

nevi

Independent val ida.onof myPath

•   1400lesionsindependentlyreviewedby3experts–   Tripleconcordance:993lesions(70.9%)–   Excludedindeterminatescores:860lesions(24%malignant,76%benign)

–   Excludedlesionswith<10%tumorvolume:763lesions

•   Sensi<vity91.5%--Specificity92.5%–   Falsenega<ves-len<gomalignaanddesmoplas<cmelanomavariants

–   Falseposi<ves-dysplas<cnevi

Clarkeetal.,Cancer,October2016Clarke,ASDPOctober2016

29yearoldpregnantfemalewithchanginglesiononback

Junc<onaldysplas<cnevuswithmoderatetosevereatypia

MyPathanddiagnos.cal ly chal lenging

les ions

•   39unequivocallesions:62%sensi<vity,95%specificity

•   78challenginglesionswithexpertconsensus(27favormalignant,30favorbenign,21ambiguous)

•   myPathscoreagreedwithhistologyin64%,agreedwithFISH70%of<me–   Limitedbylackofclinicaloutcome

SUMMARY:myPathscorecanincreasediagnos<ccertaintyandinfluencetreatmentrecommenda<ons,BUTperformancenotproveninambiguouslesions

Mincaetal,ModernPathology,August2016,29:832-843.

Molecular tests for melanomadiagnosis

Summary

•   FISHandmyPathsensi<vityandspecificity~90%inunequivocalmelanomasandnevi

•   FISHsensi<vitydropsto50-100%andspecificityto74-87%inAST

•   CGHcanaidinatypicalcaseswithnega<veFISH,buthamperedbylimitedavailabilityandreimbursement