new who classification liver and bile duct...
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New WHO Classification
Liver and Bile Duct Tumours
P. Schirmacher
Institute of Pathology
University Hospital Heidelberg
Changes/Aims in 5th Edition
• First volume of 5th edition; frontrunner effect
• Stringent formal criteria, harmonized terminology; evidence based claims (not casuistic)
• Completely rewritten; concise text, more tables, better figures
• Non-organ specific entities (haematolymphoidneoplasms, mesenchymal tumors, metastases andothers, hereditary tumor syndromes) taken out ofthe organ chapters, but not in NET
Pattern of HCC
• No significant link to pathogenesis, prognosis and therapy
• Diffuse (cirrhotomimetic) pattern generally underestimated by imaging
nodular massive
diffuse multifocal
HistologicalPattern
(Micro)trabecular
Solid
Macrotrabecular
Pseudoglandular
Macroscopic Pattern
Fat
Mallory hyalin
MDBs
Globular hyaline inclusions (α1AT?) Pale bodies
(fibrinogen?)
Glycogen
(clear cell change)
Copper Oncocyticchange
Bile
• No relevance for prognosis or therapy
• May support diagnosis (metastases)
Cytological Changes (Pattern)
Immunohistological Markers of Hepatocellular Differentiation
WHO-Classification of Tumours (5th ed)Digestive System Tumours
G1 G2 G3 G4
• Several grading schemes (Edmondson-Steiner (1954), AFIP (Nzeako et al., 1995), Burt et al., 2018); none of the grading approaches validated
• No internationally consented, harmonized grading• Prognostic relevance (survival after resection and transplantation)• Needle biopsy grading shows reasonable correlation with resection grading
The Grading Issue
Nzeako et al., 1995
Numeric Descriptive Global Criteria Remarks
I Welldifferentiated
Hepatocyticdifferentiation √Malignancy ?
Maximally mild nuclearatypia; ‚normal-like‘ cytoplasmic differentiation
Differential diagnosisDysplastic nodule, Adenoma
II Moderatelydifferentiated
Hepatocyticdifferentiation √Malignancy √
Moderate nuclear atypia; increased cytoplasmicbasophilia
III Poorlydifferentiated
Hepatocyticdifferentiation ?Malignancy √
Marked nuclear atypia Includes former grade IV, also anaplasia, sarcomatoid dediff.
Proposal: Pragmatic Grading Scheme
Molecular Subtyping of HCC?
Calderaro, J. et al, J. Hepatol. 2017
Open questions:• Unclear whether types or stages• Only stage I/II tumors• Relation/hierarchy of
pattern/changes N• not distinct but overlapping groups• Some defined subtypes missing
Fibrolamellar HCC
DNAJB1-PRKACA Translocation
Honeyman et al., Science, 2014
DNAJB1: Chaperon DNAJ homologue
PRKACA: catalytic domain of PKA
Chr. 19p13.12
• 24/24 FLC positive
• 7/7 FLC PRKACA overexpression
• 0/80 other primary liver tumors positive
• Multinational trial: 102/103 FLC positive
PGK (126 bp)
Graham et al., Mod Pathol, 2015, 2017
DD: FLC-like areasin conventionalHCCSolution:TL-testing
Chromophobe HCC
Wood et al., Mod Pathol 2013
chromophobe abrupt anaplasia
ALT-Phenotype (alternative lenghtening of telomeres)
pseudocysts
- Association with HBV (50%)
- Frequency: 5% of HCCs
- 100% ALT vs. 7% in unselected HCCs
Scirrhous HCC
Characteristics:
• Abundant intratumoral stroma; no capsule
• TSC1/TSC2 mutations; activatedTGFß signalling
• estimated frequency: 3-4%
• Mimicks ICC on imaging
• Prognosis better?
DD: ICCA/Metastasis; solution: Markers of hepatocellular and pancreato-biliary differentiation
Macrotrabecular massive (high AFP) HCC
Calderaro et al., J Hepatol 2017
Lymphocyte-rich HCC(syn: Lymphoepithelioma-like; lymphocyte-rich stroma)
• Better prognosis
• All EBV negative, except 1 (Si et al., 2004)
Emile et al., 2000, Si et al., 2004, Chen et al., 2007, Nemolato et al., 2008, Wie et al., 2015, Cacciato-Insilla et al., 2015, Wang et al., 2017
Homogenous subtype (immunoprofile; hot/cold?)DD: hepatic lymphoma/lymphoma infiltration of liver; solution: prove HCC-cells
Granulocyte-rich HCC(Syn: GCSF-producing)
• Diffuse granulocytic infiltration; sarcomatoid changes• GCSF production by tumor cells• GCSF, CRP, WBC elevated; fever• Resolves after resection
Yamamoto et al., 1999, Araki et al., 2007, Joshitaet al., 2010, Kohno et al., 2013, Nagata et al., 2016
DD: undifferentiated/rhabdoid carcinoma (INI-/SWI/SNF-deficient) ?
Steatohepatitic HCC
Characteristics:
• Histological features ofsteatohepatitis;
• 60% steatohepatitis in nontumorous liver (ETOH, metabolic syndrome)
• estimated frequency: 5-10%
• Activated IL-6/JAK/STAT signaling
HCC
DD: Steatohepatitis; solution: recognize/prove neoplastic nature
Steatohepatitic HCC– mod. Gomori
Clear Cell HCC
Characteristics:
• DD: metastasis (kidney)
• Unclear distinction from clear cellpattern (80%?)
• No specific molecular changes so far
• estimated frequency: 3-5%
• better prognosis?
DD: clear cell carcinoma of kidney metastasis (rarely other extrahepatic primariesSolution: non-clear cell areas/markers of hepatocytic differentiation
Distinct HCC Subtypes
Subtype Histology Molecular Clinical Frequency Prognosis Reference
Steatohepatitic Steatohepatitictumor appearance
IL-6/JAK/STAT activation
5-10 ~ Salomao et al., 2010
Clear cell >80% clear cellmorphology; glycogen
? Later recurrenceafter resection
3-7 ↑ Li et al., 2011
Macrotrabe-cular massive
Macrotrabeculargrowth >50%
High homogenousAFP expression; p53mut; FGF19amp
High AFP, poorprognosis, vascularinvasion
5 ↓ Calderaro et al., 2017
Chromophobe Light/clearcytoplasm, abrupt anaplasia
Alternative lengthening oftelomeres (ALT)
3 ~ Wood et al., 2013
Fibrolamellar Oxyphiliccytoplasm, lamellar fibrosis
DNAJB1:PRKACA Translocation
2 ~ Graham et al., 2015, 2018
Scirrhous Dense tumoralfibrosis, no capsule
TSC1/2 mutations; TGFß activation
Young (median 25), no primary liverdisease
2 ↑/~ Matsuura et al., 2005
Neutrophil-rich Diffuse neutrophils GCSF expression Elevated WBC, CRP, IL6
<1 ↓ Nagata et al., 2016
Lymphocyte-rich
Lymphocytes >> tumor cells
?; not consistentlyEBV-related
1-2 ↑ Emile et al., 2000; Nemolato et al., 2008
HCC ‚NOS‘
Defined subtypes (~ 20-30%): specific morpho-molecular phenotypes
Molecular Pattern
Reanalysis
?
Morpho-molecular HCC Classification
Macroscopic Pattern
Histologic Pattern
Cytologic Pattern
Development of HCC
premalignant lesion small HCC (<2 cm) classical HCC
early HCC
progressed HCC
Dysplastic
FocusDysplastic Nodule (DN)
vague
nodular
Nodule-in-
nodule HCC
G1
G2
International Consensus Group
for Hepatocellular Neoplasia (2009)
G2
G3
G3
advanced HCC
early HCC Progressed small HCC
low-grade high-grade
‚Matrix Diagnosis‘ – HCC and Precursors
• Gender: m > f
• Patient from endemic risk factor area?
• HCC-predisposing diseases: HBV, HCV, NASH, gen. haemochromatosis, alcohol abuse
• State of non-tumorous liver: chronichepatitis, cirrhosis
Molecular Alterations during HCC Development
WHO-Classification of Tumours (5th ed)Digestive System Tumours
Diagnostic Criteria for HCC Precursors and Malignant Transformation
WHO-Classification of Tumours (5th ed)Digestive System Tumours
Tatrai et al., Lab Invest 2006
RN regenerative
nodule
HCC Neoangiogenesis
Sometimes suggestive, but neither sufficiently specific nor sensitive
Lennerz et al., Am J Pathol 2011
HCC – Loss of Ductular Reaction
Benign vs. Malignant
Di Tommaso et al., J Hepatol, 2009
International Consensus Group; Hepatology 49 (2009) 658-664
Distinct: progressed! (12 mm)
Vaguely nodular: early HCC
Small HCCs
Features of Early and Small Progressed HCC
WHO-Classification of Tumours (5th ed)Digestive System Tumours
Focal Nodular Hyperplasia
• No neoplasia (abnormal vascular supply), reactive/ hyperplastic proliferative lesion; no malignant transformation
• F>M
• No significant bleeding risk
• Nonspecific symptoms, if at all
• Typically diagnosed by imaging (abnormal vascularisation)
• Single and multiple (‚FNH-syndrome‘)
Central scar, abnormal vessels, ductules, inflammatory infiltrates, transitional hepatocytesIn unclear cases: GS-IHC (map-like pattern)
Hepatocellular Adenoma
Hepatocellular Adenoma Subtyping
Nault et al., Gastroenterology 2017
New Subtype: shHCA
Prostaglandin-H2 D-Isomerase533 HCAs / 411 Patienten
Henriet et al., Hepatology 2017
New Marker: ASS1+ HCA
- Argininosuccinat Synthase 1 (ASS1)-IHC detects (all?) UHCA
- Association with bleeding risk (ca. 65%)
→ shHCA also ASS1+?
Malignant Transformation of HCA
Pilati et al ; Cancer Cell 25,,2014, 428 - 441
CK7
Hepar-1
Combined HCC-CC, ‚Classical Type‘
CK7
Hepar-1
EpCAM CD117
CK19AFP
Intermediate PLC
Subtyping of Mixed LC/Combined HCC/CC
Moeini, A. et al., J. Hepatol. 2017
CholangiolocellularCarcinoma –cHCC/CCA or CCA?
cHCC/CCA, Intermediate and UndifferentiatedPLC
Subtype Definition Frequency
Combined HCC/CCA Unequivocal hepatocyticand biliary differentiation
> 2,5%
Intermediate PLC tumor cell differentiationintermediate betweenhepatocytic and biliary
Very rare
UndifferentiatedPLC
Liver cancer withoutconvincing furtherdifferentiation
Very rare
Aishima et al., Am J Surg Pathol 2007
~ periductal infiltrating type (Sasaki et al., 1998)
~ mass-forming type (Sasaki et al., 1998)
Intrahepatic Cholangiocarcinoma Two Different Entities - Macroscopy
Intrahepatic Cholangiocarcinoma Two Different Entities - Histology
Liau et al., Mod Pathol, 2014
Large Duct Type – distal, periductal infiltrating
Small Duct Type – peripheral; mass forming
Histo-pattern; mucin productionIHC: NCAM, EMA, CRP?
Intrahepatic CholangiocarcinomaTwo different Entities
CCA- large duct type; distal/central, periductal-infiltrative
ICCA- small duct type; proximal/peripheral, primary mass forming
Anatomically extrahepatic (ECCA)
Anatomically intrahepatic (ICCA)
Premalignant Biliary Changes
Kappa-Values:
Reactive: 0.42
BilIN-1: 0.40
BilIN-2: 0.16
BilIN-3: 0.44
Zen et al., Mod Pathol 2007
BilIN-1
BilIN-2
BilIN-3
Low
High
CK7 PR
Biliary Intraepithelial Neoplasia (BilIN)
Mucinous Cystic Neoplasia (MCN)
Intraductal Papillary Neoplasia of the Bile Ducts (IPNB)
Intrahepatic CholangiocarcinomaTwo different Entities – Premalignant Lesions
CCA- large duct type; distal/central, periductal-infiltrative
ICCA- small duct type; proximal/peripheral, primary mass forming
Anatomically extrahepatic (ECCA)
Anatomically intrahepatic (ICCA)
BilINIPNBMCNAdenofibroma
?
Bridgewater et al., J Hepatol, 2014
Global Incidence of ICCA
Intrahepatic CholangiocarcinomaTwo different Entities – Etiology
CCA- large duct type; distal/central, periductal-infiltrative
ICCA- small duct type; proximal/peripheral, primary mass forming
Anatomically extrahepatic (ECCA)
Anatomically intrahepatic (ICCA)
FlukesPSCStones
HBV, HCVNASH, ASHFe, CuCirrhosis
Different Molecular Pattern of ICCA vs ECCA
Nakamura et al., Nature Genet, 2015
Graham et al., Hum Pathol, 2014
Goeppert, Rössler et al, 2018
Intrahepatic CholangiocarcinomaTwo different Entities – Molecular Pattern
CCA- large duct type; distal/central, periductal-infiltrative
ICCA- small duct type; proximal/peripheral, primary mass forming
Anatomically extrahepatic (ECCA)
Anatomically intrahepatic (ICCA)
RASPRKACA/B-TLELF3ARID1B
IDH1/2FGFR2-TLBRAF V600BAP-1ARID1A
Mutation ICC (%)
KRAS/NRAS 10-20
TP53 Mut 10-20
FGFR2 TL 20-30 *
IDH1/2 Mut 20-35 (*)
SMAD4 Mut 2-10
Her2/neu Mut 2-5 (*)
BRAF V600E 3-6 (*)
ARID1A 5-15
BAP1 5-15
PTEN 0-5
EGFR 2-3 (*)
BRCA1/2 3-4 (*)
NTRK-TL 2-3 (*)
ALK-TL 1-2 (*)
ROS1-TL 2-3 (*)
Frequency of druggable mutations in ICCA
60-80% ?
3/11 Kipp et al., Hum Pathol, 2011
IDH-Mutations in ICC
Grassian, Curr Opin Gastroenterol 2014
IDH-Mutations in ICC
• Better natural course
• Correlation with morphology(clear cell change)
• Entity-specific IDH-mutation spectrum
• Poor response to IDH-inhibition in ICC (high resistance rate)
• Option: broader/2nd generationinhibition
Harding et al., Cancer Discov, 2018
Mutation ICC (%)
KRAS/NRAS 10-20
TP53 Mut 10-20
FGFR2 TL 20-35
IDH1/2 Mut 20-35
SMAD4 Mut 2-10
Her2/neu Mut 2-5
BRAF V600E 3-6
ARID1A 5-15
BAP1 5-15
PTEN 0-5
BRCA1/2 3-4%
NTRK-TL 2-3
ALK-TL 1-2
ROS1-TL <1
TLs/Gene Fusions in ICCA
Moeini et al, CCR, 2016
Gene fusions are a particular featureof small duct ICC
Heterogenous
Tailing effect
NTRK Gene Fusions
• Large intronic regions1,2
• Low complexity sequence, GC rich
• Inconsistent break points and fusion partners
• Fusions occur in a tumour-agnostic fashion
• Is endogenously expressed in some tumour/tissue types
• What does this means for testing?
– DNA-only panels, even with intronic coverage, lack sensitivity of detection
– IHC may lack specificity
– RT-PCR is not comprehensive
– FISH requires at least 3 assays
Take home: RNA-based NGS is the preferred method for detecting NTRK gene fusions in tumors
NTRK, neurotrophic tyrosine receptor kinase1. Sigal D et al. J Natl Compr Canc Netw 2017;15:1317-22; 2. Gagan J, Van Allen EM. Genome Med 2015;7:80; 3. Vaishnavi A et al. Cancer Discov 2015;5:25-34
Conclusion• 5th edition with more stringent formal criteria, harmonized
terminology/definitions and evidence based claims
• Aiming for increased reproducibility (worldwide, different expertiselevels), clinical relevance/making meaningful trials possible and tumordocumentation/registries
• Completely rewritten and updated in all subchapters
• Non-organ-specific entities taken out of organ chapters; relevant for liverespecially in vascular tumors and metastases!
• Novel conclusive morpho-molecular (sub)classification of HCC and ICCA reflecting macro- and histomorphology, etiology, pathogenesis, and clinicalpicture; should guide further trials and therapeutic approaches
• ICCA exemplifies the potential conflict between anatomical/organ-basedand histological classification/typing
• Small duct ICCA offers a high frequency of translocations and potential therapeutic options; should be recognized as specific entity
Future• Further shapen morpho-molecular typing (more
data) especially in ICCA; data with new technologies(e.g. proteomic, methylation, digital imageanalysis/AI)
• Integration in clinical and diagnostic trials, tumorboards etc.
• Basis for further translational research approaches; more predictive markers
• Use it, spread the news, and please give feedback!
• Check the internet version
• Update planned for 2021 (internet)
Thank you!Authors of the liver chapter:
C Sempoux, P Bioulac-Sage, S Kakar, JC Nault, MS Torbenson, IOL Ng, YN Park, M Roncalli, M Sakamoto, R Saxena, A Quaglia, WM Tsui, Y Nakanuma, O Basturk, S Aishima, I Esposito, DS Klimstra, M Komuta, Y Zen, F Kondo, P Schirmacher
Authors of the bile duct chapter:
I Esposito, S Aishima, O Basturk, Y Nakanuma, DS Klimstra, JC Roa, NV Adsay, J Arola, WM Tsui, Y Zen, S La Rosa
Editors of chapters:
V Paradis, NY Park, M Fukayama, AK Lam, DS Klimstra, P Schirmacher
Ian Cree and the IARC Team