Elements of PET/CT Reporting1. Clinical History a. Indication i. tumor type ii. abnormality to be evaluated iii.specificclinicalquestion b. Relevent history i. biopsy results ii. chemotherapy iii. radiotherapy iv. other treatments v.significantmedical/surgicalhistorythatmayhaverelevenceforPET/CTinterpretation

2. Procedure a. PET i. radiopharmaceutical type ii. radiopharmaceutical dose iii.routeofadministrationandinjectionsite iv.scancoverage(skullbase-thigh,vertex-feet,etc.) 1.Noteshouldbemadeofanyadditionaldedicatedacquisitions(i.e.delayedchestforSPN, ordelayedheadandneck) v.uptaketime(approximate) vi.serumbloodglucose(ifmeasured) vii.medicationsadministeredaspartofprocedure(i.e.anxiolytics,musclerelaxants,betablockers, premedicationforcontrastreaction) b. CT i. noncontrast ii. iodinated intravenous contrast – type and amount iii. oral contrast – type and amount c. Notes i.explanationofanydeviationfromstandardprotocol ii.specialmeasurespatientmayhaverequiredwhileatfacility,i.e.supplementaloxygen,treatment ofcontrastreaction

3. Comparison a. Prior PET or PET/CT studies b. Other studies, i.e. CT, MRI, US, mammography, nuclear medicine

4. Findings a. Order of importance format b. Anatomic site format c. Hybrid format

5. Impression

6. Sample Normal Reports

May 2009

1. Clinical HistoryThedecisiononhowmuchdetailtoincludeinthisportionofareportisapersonalone,butthereshouldbethreebasicpiecesofinforma-tion:a. Indication for the examination Incasesofroutinefollowupscanning,thismaybeasimplestatementsuchas“Restagingofnon-Hodgkinlymphoma.”IfthePET/CTisbeingperformedforaspecificreason,however,thisinformationshouldbeincluded,suchas“Historyofcolorectalcancer,nowwithrisingCEA.”Theindicationshouldbeastatementoftheclinicalissue(s)whicharetobeansweredattheendofthereport.ToconformwithpresentCMSguidelines,theindicationsforPETshouldbecategorizedas:Diagnosis,InitialStaging,Restaging,orResponsetoTherapy.

b. Relevant history ThisportionoftheClinicalHistorysectionshouldcontaininformationregardingthepatientwhichcouldhaveanimpactontheinterpre-tationoftheexamination.Themostcommoninformationwillpertaintohistopathologicresults,andprevioustreatments(suchas“Priorchemoradiation,completed3monthspriortothisscan”).Otherpertinentinformationwouldincludeconcurrentandongoingtherapy,relevantsurgeries,infection,andsystemicprocessesthatmightinterferewithinterpretationsuchassarcoidosis,vasculities,etc.

c. Information needed for billingIfnotprovidedintheabovesections,thereshouldbeaclearstatementregardingthepurposeofPETscanningusingappropriateter-minologytofacilitatebilling,suchas:“IndeterminatenodulefoundonchestCT.PET/CTisobtainedforevaluationofsolitarypulmonarynodule.”

2. Procedure and Protocol a. PET Procedure

i.RadiopharmaceuticalAswithanynuclearmedicineprocedure,itisimportanttolisttheradiopharmaceutical(includingtypeanddose),therouteofad-ministration,andthesiteofinjection.

ii.ScanfieldRegardlessofwhetheraPET/CTstudyiscodedasaregionalstudy,askullbasetomidthigh,orwholebody,theactualaxialcover-ageofthescanshouldbedescribedinordertoconveywhatareasofthebodyarebeingevaluated,andwhatareaslieoutsidethescanfield.Thisdescriptionshouldbemadeusingappropriateanatomicnomenclature.Forexample,manyprotocolsforimagingofpatientswithcancersoftheheadandneckbeginatthevertexoftheskullandextendthroughthepelvis.Scansinpatientswithknownmalignantinvolvementofthefemurmaybeginattheorbitandextendtotheknees.Truewhole-bodyscansforpatientswithmelanomaextendfromthevertextothefeet.

iii.LocalizationtimeTheapproximatetimebetweeninjectionandscanningshouldbegiven.Inmostcases,arangeisappropriate,suchas60-90minutes,butspecialnoteshouldbemadeofcasesinwhichthelocalizationtimeiseithershorterorlongerthannormal.

iv.SerumbloodglucoseSerumbloodglucoseshouldbemeasuredonpatientsundergoingFDG-PETorPET/CTinordertocomplywithACRguidelines.Theresultofthisserumglucosemeasurementshouldbeincludedinthereport.Inadditiontoitsrelevancetotheinterpretationofthecurrentstudy,thebloodglucosemayhavebearingwhenfollowupscansarebeingperformedatdifferentserumglucoselevel.

v.MedicationandInterventionIfmedicationswereadministeredtothepatientaspartofprotocol(i.e.anxiolytics,furosemide,etc.)thetype,dose,androuteofadministrationshouldbenoted.Anyinterventionsperformedaspartoftheprocedureshouldalsobedescribed,suchasplacementofaurinarycatheter.Ifanoralpremedicationregimenwasusedpriortointravenouscontrastadministration,thisshouldbenoted.

vi.OtherdetailsSomePET/CTprotocolsmakeuseofadditionalacquisitions,suchasdelayedscanningofthechestforpatientswithindeterminatepulmonarynodules, ordedicatedbrain imaging inpatientswithasuspicionofcerebraldisease.Somepatientsarescanned inspecificpostions,suchasforradiationtreatmentplanning,usinganimmobilizationdevices.SuchadditionstothestandardPET/CTacquisitionshouldbedescribed.2

b. CT ProcedureSomedescriptionoftheCTprocedureshouldbegiveninthereport,withparticularattentiongiventowhetherthestudywasperformedwithout contrastmaterial, orwhether intravenous contrast, oral contrast, or bothwere administered. If intravenous contrastwasadministered,thetypeandamountofcontrastshouldbestated.Detailssuchastubecurrent,pitch,etc.maybeincluded,butareoptional.RegardlessoftheCTparametersused,itshouldberecognizedthattheCTportionofthestudycontainsinformationwhichshouldbeusedintheinterpretationofthePETportionoftheexamination,whetherthroughanatomiclocalization,tissuecharacteriza-tionbydensity,orpatternsofenhancement.Assuch,theuseofsuchtermsas“non-diagnosticCT”or“CTusedonlyforattenuationcorrection”arediscouraged.i. IftheCTtechniqueusedisofsignificantlylowerqualitythanroutinediagnosticCTataparticularinstitution,itmaybeappropriatetosupplythedetailsfothetechniqueused,i.e.40mAs,120kVp.

ii. IfadiagnosticCTinterpretationisperformedontheCTcomponentofaPET/CTstudy,thenthedetailsoftheCTtechniqueshouldbeprovidedintheseparateCTreports.

c. Additional notesAnydetailsregardingadversereactionstocontrast(includingsigns,symptoms,andtreatment),specialmeasuresrequiredbythepa-tient(e.g.supplementaloxygen,IVfluids),andanysignificantdevationfromstandardprotocolshouldbeincludedintheofficialreport.Detailsofsuchinterventionsarealsotypicallykeptinaseparatenurse’snoteorincidentreport.

3. Comparisona. Dates of any PET or PET/CT studies used for comparison should be given. If no previous PET studies are available, this should be

stated.b. In addition to comparing to other PET/CT studies, it is necessary to correlate the findings on PET/CT with other imaging studies including CT, MRI, plain films, etc.

4. FindingsItisvitaltohaveanorganizationalschemewhenapproachingPET/CT,giventheextentofinformationavailableonthescan.TherearetwoprimarystylesofPET/CTreporting,termedhereas“Priority”and“AnatomicSite.”Ideally,PET/CTreportsincorporatefeaturesofboth.

a. PriorityInthisscheme,thefindingsaredescribedintheorderofrelevancetotheclinicalcareofthepatient.Initssimplestform,suchare-portfollowstheTNMstagingclassificationforthetypeoftumorbeingevaluated.Inothercases,itmaybeginwiththelargestormostclinicallysignificantsiteofrecurerntdisease,followedbyadditionalfindingsoflessimmediateimportance.OncethepertinentPETfindings(alongwithcorrespondinganatomicdescriptorsfromtheCTportionofthestudy)aredescribed,thereshouldbeadescriptionofsignificantCTfindingswhicharenotFDG-avid,followedbyincidentalfindings,eitheronPETorCT,whichareunlikelytohaveanimpactonpatientcare.Theoverallorganizationcanbeoutlinedasbelow:

Dominantfindings:[findingsandpertinentnegativesdirectlyrelevanttotheclinicalquestion;maybeadescriptionoftheprimarylesionusingTnomenclatureorofthedominantsite(s)ofrecurrentdisease]Metastases:[additionalsitesofabnormalradiotracerlocalizationsuspectedtorepresentnodaland/orextranodalsitesofmetastaticdisease]OtherabnormalPETfindings:[secondprimarytumors,diffusethyroidactivity,etc.]IncidentalCTfindings[lungnodulesw/oFDGuptake,AAA,renalmasses,etc.]NormalphysiologicFDGuptake:[brownfat,prominentmuscleorintestinaluptake]

b. Anatomic siteAsecondschemewhichismoreconsistentandversatileisorganizationbyanatomicregion.Inthisstyleofdictation,thefindingsonbothPETandCTaregroupedregionofthebody,withaseparatesectionfordescriptionofmusculoskeletalfindings.Thisstyleiscondu-civetoa“top-to-bottom”reviewofthePET/CT,whilemaintainingastructuredapproach.Withineachsection,itisstillappropriateto

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beginwithsignificantPETandCTfindings,followedbyrelevantCT-onlyfindingsandincidentalobservations.Thisstyleoforganizationcanbeoutlinedasbelow:

Foreachlevel,describethepositivefindings(bothPETandCT),pertinentnegatives,andanyprominentorasymmetricphysiologicuptakethatmightbemisinterpretedbythenaïveviewer.Headandneck:Chest:AbdomenandPelvis:Musculoskeletal:

c. Synthesis of Priority and Anatomic SiteIdeally,aconciseandinformativePET/CTreportwillrepresentacombinationofthetwoprimarydictationstyles.Thiscanbestbeac-complishedbyorganizingtheoverallreportbyanatomicregion(HeadandNeck,Chest,AbdomenandPelvis,Musculoskeletal),andapplyingOrderofImportancetoeachindividualsection.Thisassuresthatthereporthasanoverallstructureandconsistency,andthattheinformationiscompartmentalizedandpresentedinaclearfashionwithreadyaccesstorelevantinformation.Thishybridstyleisillustratedinthenormalreportsattheendofthisguideline.

d. General reporting notesInbothorganizationalschemes,diseaselocationshouldbedescribedusingstandardanatomicdescriptors,ideallyinconformancewiththeRADLEXconvention.Itisappropriatetoprovidesizemeasurementsfornodulesandmasses,eitherasasingleaxialdiameter(perRECIST)orin2or3orthogonaldirections.Ifasinglelinearmeasurementisreportedthereshouldbeastatementthatitistheshortorlongaxis,realizingitiscommonpracticeindiagnosticimagingtousetheshortaxisdiameter,whileinoncology(RECIST)thelargestdimensionofalesionisusedforfollowupcomparison.PET/CTisoftenusedasafollowuptoanatomicimaging,andinsuchcasesitisadvisabletocompareanatomicinformation(i.e.increasing,stable,ordecreasinglesionsize)inadditiontonotingthemetabolicfindingsonPET.Onewordofcaution,however.WhenCTandPET/CTareperformedseparatelybutinclosetemporalproximity,thesizemeasurementssuppliedbyCTshouldtakeprecedence.IflesionsizesarereportedonPET/CT,careshouldbetakenthatthereisconcor-dancebetweentheCTandPET/CTreports,sincedisparatemeasurementsinstudiesperformedaroundthesametimeleadtoconfusionandfrustrationonthepartoftheclincians.ItisthereforeimportantthatthereiscommunicationbetweenreadersinsituationswherethePETandCTarereadindependently,toassurethataconsistentmessageisgiven.

Onceadescriptionofsitesofthepatient’sknownorsuspectedtumoriscompleted,incidentalsitesofFDGuptakeshouldbeaddressed.Thesemightincludesecondprimarytumors,inflammatoryorinfectiousprocesses,orbenignbutFDG-aviddisease.TypicalbenignsitesofFDGuptakecanalsobenoted,suchasbrownfatandfunctionalchangesoftheovulatorycycle.ThereshouldbeafulldescriptionofeachsitealongwithappropriateCTfindings.

Finally,incidentalCTfindingswithoutFDGuptakeshouldbenoted.ThisincludessuchfindingsasenlargednodesthatdonottakeupFDG,pulmonaryfindings(emphysema,pneumothorax,non-avidlungnodules),aorticdilation,adrenalnodules,renalmassesorstones,andgallstones.AnyfindingwhichwouldbelonginafullCTreportshouldbeincludedinthereportofaPET/CT.

5. ImpressionTheimpressionisthemostimportantsectionofanyimagingreport.Manyreferringphysiciansstartwiththeimpression,andreadtheFindingssectiononlyastimeallows.Itisessentialthatalltheimportantinformationdiscoveredinthestudyispresentedhereinaclearandsuccinctway.Thegoalsoftheimpressionsectionshouldbe:

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a. Brief and concise b. Answer the clinical question c. Give a precise diagnosis d. When a precise diagnosis is not possible, a clear and organized differential diagnosis should be given e. It may be appropriate to discuss the use of additional imaging studies or follow up, if this would aid in the arrival at the correct diagnosis

Theimpressionshouldstartoffwithaclearstatementifitisabnormal.Examplesinclude:“Definiteevidenceofmalignancyinleftupperlobewithipsilateralhilarandmediastinalmetastases”or“Probablemalignancyinrightpiriformsinus,withoutevidenceofmetastases.”Forfollowupscansaftertherapy,boththemetabolicresponseandanatomicresponseshouldbecommentedonintheimpression.

Inthesamesense,ifeverythingappearsbenign,itisimportanttomakesuchastatementatthebeginningoftheimpressionsuchas“Negativestudyformalignancy”.Notethatthesimilarexpression“Noevidenceforactivemalignancy”isnotasdefinitiveandcanbemisinterpretedbythereferringphysician.

Considerablycaremustbeexercisedinselectionofthedescriptionsofcertaintyusedintheimpression.Sometermssuchas“Absent”,“excludes”,“unlikely”,“probable”,“certain”and“definite”areinterpretedinmuchthesamewaybythereferringphysicianandtheradiologist.Othercommonlyusedtermssuchas“unlikely”,“highlysuggestive”,“compatiblewith”,“worrisome”,and“suspicious”areoftenunderstoodquitedifferentlybythereferringphysicianfromwhatisintended.

Althoughthereisoveracenturyoftraditionofusingvaguedescriptivephrasestocommunicatethecertaintyofinterpretation,itwouldbeidealtomovetodefinite,numericprobabilityestimatesintheimpression.However,thisislikelytobeunacceptabletomanyradiologists.Thefollowingphrasescanbeusedtocommunicatelevelofcertaintyandshouldberecognizedappropriatelybymostreferringphysicians:“definitelybenign”,“probablybenign”,“equivocal”,“probablymalignant”,“almostcertainlymalignant”,“definitelymalignant”.

Thegoalistooptimizecommunicationwiththereferringphysician.Itthefindingsaredefinite,itisimportanttocommunicateusingtheright,veryspecificwords.Ifthereisrealuncertaintyabouttheinterpretation,thenitisessentialthattheuncertaintybeclearlycommu-nicated.Vaguelanguageonlyconfusesthereferringphysicianandcanresultinsub-optimalpatientcare.

Finally,itshouldberecognizedthatradiologyreportsarenowmadeavailabletopatientsatmanyinstitutions.WhileitisimportanttobedefinitiveintheImpressionsectionofPET/CTreports,itisalsoimportanttorecognizethelimitationsoftheimagingstudies,andthattheresultsmustbetakeninthecontextofeachclinicalsituation.Reportsmustconveythenecessaryinformaitontothereferringphysicianwithoutcausingunnecessaryanxietytothepatient.

6. Sample Normal Reports

BothofthefollowingreportsareexamplesofhowaPET/CTreportshouldbeorganizedusingtheaboverecommendations.BothareasynthesisofPriorityandAnatomicSitestyles.NotethateventhoughneitherpatienthasPETfindingssuggestingdiseaserecurrence,thereisstillanumberofrelevantpositiveandnegativefindingsconveyedineachreport.Theorganizationofeachsubsectionisdifferentforthetworeports,reflectingtheapplicationofOrderofImportance.Inthefirstcase,thepertinentnegativeshavetodowiththestatusoflymphnodesandspleen,andtheseareaddressedearlyineachsubsection.Inthesecondcase,apatientwithanindeterminatepulmonarynodule,thenoduleitselfisaddressedfirstandforemost.NotethateventhoughthenoduleisnegativeonPET,thereisstillaTNMformattotheChestsubsectionframedinthecontextofpertinentnegativefindings.

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Sample Normal Report #1 – Negative Lymphoma

PATIENTNAME:Smith,JohnV.EXAMDATE:__/__/____MRN/DOB:123456-7

EXAMINATION: 18F-FDGPET/CTScan,SkullBasetoMid-Thigh

CLINICAL HISTORY: Restagingoffollicularlymphoma,statuspostchemotherapycompletedin2004.

PROCEDURE:12.5mci(18F)-fluorodeoxyglucosewasadministeredintravenouslyviatherightantecubitalvein.Toallowfordistributionanduptakeofradiotracer,thepatientwasallowedtorestquietlyfor60-90minutesinashieldedroom.Imagingwasperformedonanin-tegrated16-slicePET/CTscanner,withscanningfromtheskullbasetothemidthigh.Serumbloodglucoseatthetimeoftheinjectionwasmeasuredat104mg/dL.CTscanningwasperformedwithoutoralorintravenouscontrastmaterial.

COMPARISON: PreviousPET/CTperformed7/10/07andCTperformed5/4/07.

FINDINGS: Head and Neck: Thereisnonodalhypermetabolismintheneck.ThevisualizedportionsofthebrainarenormalinappearanceonCT.

Chest:Thereisnonodalhypermetabolisminthechest.Thereareslightchangesofcentrilobularemphysemaatthelungapices.Thereareno pulmonary nodules.

Abdomen and Pelvis: Thereisnonodalhypermetabolisminretroperitonealorpelvicchains.ThespleenisnormalinsizeandFDGavidity.Incidentalnoteismadeoftinystonesinthelumenofthegallbladder,withnoCTevidenceofcholecystitis.

Musculoskeletal:Marrowuptakeiswithinnormalrange.

IMPRESSION: Noevidenceofrecurrentlymphoma.

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Sample Normal Report #2 – Negative SPN

PATIENTNAME:Smith,JohnV.RECORDNUMBER:123456-7EXAMINATION:PET/CTBaseofskulltomidthighEXAMDATE:__/__/____

CLINICAL HISTORY:Mr.Smithisa64yearoldmanwhowasincidentallyfoundtohavearightupperlobepulmonarynoduleonchestx-ray.CTon07/01/2008showeda10mm,smooth,noncalcifiednoduleintherightupperlobe.Therewasnohilarormediastinaladenopathy.Therearenopriorstudiesforcomparison.Thepatienthasa40-packyearsmokinghistory,andnohistoryofcancer.ThepatientisreferredforPET/CTformetaboliccharacterizationofthenoduletodeterminethelikelihoodofmalignancy.

RADIOPHARMACEUTICAL:F-18fluorodeoxyglucose(FDG)15.0mCiIV.

COMPARISON STUDY:CTThorax07/01/2008

PROCEDURE:Thepatient’sfastingbloodglucoselevelwas100mg/dL.ThepatientwaspositionedinthePET/CTscannerapproximately60minutesafterinjectionoftheradiopharmaceutical.Anon-contrastCTscanwasacquiredfromthebaseoftheskullthroughtheinguinalregion.A3Demissionscanofthesameareawasacquiredin6bedpositionsover12minutes.Imageswerereviewedinthetransaxial,coronal,and sagittal planes.

FINDINGS:Head and neck:Thereisnocervicaladenopathy.PhysiologicFDGuptakeisseenintheoropharynx,salivaryglands,andlarynx.

Thorax:Thereisa10x12mmsmooth,noncalcifiednoduleintheupperlobeoftherightlung(image197)thatisunchangedcomparedtoCTon07/01/2008,andshowsnoFDGuptake.Therearenootherpulmonarynodulesorothersignificantparenchymalabnormalities.Thereisnosupraclavicularoraxillaryadenopathy.Thereisnohilarormediastinaladenopathy.NormalFDGuptakeisseenthroughoutbothlungs.Therearenopleuralorpericardialabnormalities.PhysiologicFDGuptakeisnotedintheheart.Thecaliberofthethoracicaortaisnormal.Thethyroidgland is normal.

Abdomen and pelvis:Thereisnoadenopathyornodalhypermetabolismintheabdomenorpelvis.Theliver,gallbladder,pancreas,andspleenarenormal.Therearenoadrenalnodules.PhysiologicFDGexcretionisseeninthekidneysandbladder.Thecaliberoftheabdominalaortaisnormal.

Musculoskeletal:NormalFDGactivityisseenintheaxialskeleton.NoblasticorlyticlesionsarenotedonCT.

IMPRESSION:The10x12mmrightupperlobepulmonarynoduleseenonCTshowsnoFDGuptakeaboveregionalbackground,suggestingabenignetiology.Aslow-gradepulmonarymalignanciessuchasbronchoalveolarcarcinomamaynotbehypermetaboliconPET,CTfollowupisrecommendedto assure nodule stability.

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