Download New Imaging Concepts in Central Nervous System Neoplasms

New Imaging Concepts in
Central Nervous System Neoplasms
Maarten Lequin
Department of Pediatric Radiology
Wilhelmina Children’s Hospital/University Medical Center Utrecht
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
• How will it change our radiological thinking?
– Diagnosis, imaging protocols, treatment strategies
• When to use?
– Conventional and additional advanced MR sequences
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
– Transcriptional profiling
new brain tumor subtypes
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
– Transcriptional profiling
– Subtyping
new brain tumor subtypes
better understanding of tumor behaviour
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
– Transcriptional profiling
– Subtyping
– Subtyping
new brain tumor subtypes
better understanding of tumor behaviour
predict better outcome and may influence
treatment strategy choices
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
– Transcriptional profiling
– Subtyping
– Subtyping
– Subtyping
new brain tumor subtypes
better understanding of tumor behaviour
predict better outcome and may influence
treatment strategy choices
new concept of radiological thinking
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
– Transcriptional profiling
– Subtyping
– Subtyping
– Subtyping
new brain tumor subtypes
better understanding of tumor behaviour
predict better outcome and may influence
treatment strategy choices
new concept of radiological thicking
– Predict subtype
better assess outcome and treatment
strategy choices
Molecular tumor subtypes
MR image characteristics
Molecular markers
“Targeted” treatment
Prognosis
Molecular subtypes in Brain tumors
From 2007 to 2016 WHO Classification of CNS tumors
some major changes
• Formulating concept of how CNS tumor diagnoses are structured in the
molecular era
• Major restructuring of diffuse gliomas, with incorporation of genetically
defined entities
• Major restructuring of medulloblastomas, with incorporation of
genetically defined entities
• Incorporation of a genetically defined ependymoma variant
• Major restructuring of other embryonal tumors, with incorporation of
genetically defined entities and removal of the term “primitive
neuroectodermal tumor”
• Novel approach distinguishing pediatric look-alikes, including
designation of novel, genetically defined entity
Courtesy of Dr. David Louis
(A) Unsupervised hierarchical clustering of human 1.0 exon array expression data from 103
primary medulloblastomas using 1,450 high–standard deviation (SD) genes.
Paul A. Northcott et al. JCO 2011;29:1408-1414
©2011 by American Society of Clinical Oncology
Putative points of origins of WNT-subgroup medulloblastoma in sagittal, transverse, and
coronal planes.
69%
31%
75%
19%
Z. Patay et al. AJNR Am J Neuroradiol 2015;36:2386-2393
©2015 by American Society of Neuroradiology
New Imaging Concepts in Central Nervous
System Neoplasms
What could be potential radiological biomarkers
besides age and location?
– T1, T2, T1 after Gd, DWI, MRS?
– Or should we go for newer imaging modalities?
– ASL, APT, DKI?
Medulloblastoma subgroups and MR Spectroscopy
Medulloblastoma subgroups and MR Spectroscopy
4y old male. Diagnosis?
3y old girl Diagnosis?
16m old boy Diagnosis?
1y old boy Diagnosis?
New Imaging Concepts in Central Nervous
System Neoplasms
• When to use?
– Conventional and additional advanced MR sequences
New Imaging Concepts in Central Nervous
System Neoplasms
 Best differential diagnosis
New Imaging Concepts in Central Nervous
System Neoplasms
 Best differential diagnosis
 Location, age and imaging sequences
New Imaging Concepts in Central Nervous
System Neoplasms
 Best differential diagnosis
 Location, age and imaging sequences
 Posterior fossa DWI for differentiation
New Imaging Concepts in Central Nervous
System Neoplasms
 Best differential diagnosis
 Location, age and imaging sequences
 Posterior fossa DWI for differentiation
 ASL in combination with Gd enhancement (ratio)
characterise brain tumors infra- and supratentorial
New Imaging Concepts in Central Nervous
System Neoplasms
 Best differential diagnosis
 Location, age and imaging sequences
 Posterior fossa DWI for differentiation
 ASL in combination with Gd enhancement (ratio)
characterise brain tumors infra- and supratentorial
 Medulloblastoma, use MRS to differentiate between
the subgroups
6y old boy Diagnosis?
New Imaging Concepts in Central Nervous
System Neoplasms
 Supratentorial brain tumors are less easy to
characterise using conventional and advanced
sequences
 DWI and MRS are no good predictors for tumor
grading in glial tumors
 Still a lot of research has to be done to look for new
radiological biomarkers in other common brain
tumors like glial tumors
Another possible New Imaging Concept in
Central Nervous System Neoplasms
To abandon the use of Gd in neuro-oncology imaging:
 Recently multiple papers focus on the cumulation of
Gd in the brain and their possible side effects
 In the future we have to look for alternative
sequences which may give the same information
 Follow-up imaging without T1 after Gd?
 Arterial spin labeling (ASL)
 Amide Proton Transfer (APT) imaging could be an
alternative?
 Diffusion kurtosis imaging (DKI)?
New Imaging Concepts in Central Nervous
System Neoplasms
New Non-contrast Imaging Concepts in
Central Nervous System Neoplasms
Arterial spin labeling (ASL)
 No Gd contrast, measures CBF
 Three methods, continues, pulsed and pseudocontinues
 Pediatric brain tumor imaging
 Ratio with contrast enhancement may predict tumor
grading
 No tumor subtyping
New Non-contrast Imaging Concepts in
Central Nervous System Neoplasms
Amide Proton Transfer (APT) imaging
 Type of chemical exchange dependent saturation
transfer (CEST) magnetic resonance imaging (MRI), in
which amide protons of endogenous mobile proteins
and peptides in tissue are detected
 Especially useful in high grade brain tumors
 APT shows better diagnostic performance than
diffusion- and perfusion-weighted imaging in nonenhancing gliomas
Park KJ et al. Eur Radiol. 2016 Feb 16. Added value of amide proton transfer imaging to conventional and perfusion MR imaging
for evaluating the treatment response of newly diagnosed glioblastoma.
New Non-contrast Imaging Concepts in
Central Nervous System Neoplasms
Diffusion kurtosis imaging (DKI)
 Diffusion weighted method with 2 non-zero b-values
 More sensitive for brain tumor imaging
 May differentiate between low and high grade tumors
Diffusion kurtosis imaging (DKI) in a 7 year old with
resected large cell anaplastic medulloblastoma
2nd post-op study 2 weeks later
Courtesy to Susan Palasis
Normalized kmean map to MNI space
superimposed on T1 C+
kmean in right ROI is 0.9841
kmean in left ROI is 0.7342
Findings show definite tumor around 4th ventricle and foramen of Luschka.
Concern for tumor infiltration of right cerebellar hemisphere.
Summary
Challenge: balancing desires and needs
‘Stay connected’
‘Most accurate diagnosis’
• Provide the best possible diagnosis
• Utilize the most accurate, cuttingedge techniques
• Fine-tune imaging protocol (D,FU)
• Incorporate the latest molecular
signatures
• Do not disrupt current clinical
diagnosis and patient
management
• Weigh the availability and cost
of novel diagnostic techniques
• Preserve the ability for longterm clinical, experimental and
etiological correlations
Courtesy of Dr. David Louis
New Imaging Concepts in Central Nervous
System Neoplasms
• What are the new concepts?
Molecular biology, Non Gd imaging
• How will it change our radiological thinking?
Dedicated imaging protocols
• When to use?
Depends on brain tumor subtyping
New Imaging Concepts in Central Nervous
System Neoplasms
Acknowledgements:
 Pieter Wesseling
 Zoltan Patay
 Susan Palasis
 Arthur Adams
 Jeroen Hendrikse
 Dik Rutgers