Imaging in pediatric Brain tumors: from basics to molecular diagnosis (Dr Felice D'Arco)
•
12 likes•1,543 views
New insights in pediatric brain tumors after the new WHO classification (2016).
Recommended
More Related Content
What's hot
What's hot (20)
Similar to Imaging in pediatric Brain tumors: from basics to molecular diagnosis (Dr Felice D'Arco)
Similar to Imaging in pediatric Brain tumors: from basics to molecular diagnosis (Dr Felice D'Arco) (20)
More from Felice D'Arco
More from Felice D'Arco (17)
Recently uploaded
Recently uploaded (20)
Imaging in pediatric Brain tumors: from basics to molecular diagnosis (Dr Felice D'Arco)
- 1. From basics to molecular diagnosis felice.d’arco@gosh.nhs.uk
- 2. Warm-up case 1 Patient 1 Patient 2 T2 T1C+ T2 T1C+
- 3. Warm-up case 2 T2 ADC T2 ADC Patient 1 Patient 2
- 4. Warm-up case 3 T2 T2 ADC ADC T1C+ T1C+ Patient 1 Patient 2
- 6. Learning objectives Basic appearances of pediatric brain tumors (focus on brainstem and cerebellum) What’s new … and what we need to know as rediologists Pitfalls & mimics
- 8. Medulloblastoma : what’s basic and what’s new T2 ADC T1 C+CT
- 9. Taylor et al. 2012
- 10. Patient 1 Patient 2 • multiple enhancing nodules and presence of cystic components • Nodular or desmoplastic SHH !!! CAVEAT: ADC not always dark (lower cellularity)
- 11. Sonic Hedgehog Medulloblastoma (SHH) cerebellar granule neuron progenitors (CGNPs) Purkinje Cells SHH 1 proliferation 2 migration Tumorigenesi s Huang S and Yang J. 2015 Hatien M and Heintz N. 1995
- 12. D’Arco F and Bisdas S. 2018 (in press)Perrault et al 2014
- 13. Wingless Medulloblastoma - WNT (10%) Patay et al. 2015 VERY GOOD PROGNOSIS!!
- 14. Medulloblastoma group 3 and 4 (non-SHH / non-WNT) Genetic basis of this forms and embryological origin are not known. • Considered pure midline/4th ventricle tumours. • Poor prognosis (metastatic dissemination) • Sometimes do not enhance
- 15. Non-enhancing medulloblastoma D’Arco F and Bisdas S. 2018 (in press) Leptomeningeal dissemination
- 16. To recap…. LOCATION, LOCATION, LOCATION !! WNT: ponto-cerebellar angle/foramen of Luschka, good prognosis. SHH: peripheral location, intermediate prognosis. Group 3 and 4 : pure midline, enhancement +/-, poor prognosis, unknown genetics ↑DWI ; ↓ADC
- 17. Warm-up case T2 T2 ADC ADC T1C+ T1C+ Patient 1 Patient 2 Group 3 and 4 SHH
- 18. “MRI predicts molecular subtypes in about 2/3 case” (unpublished data from Sickkids hospital – Toronto) WNT on the midline…
- 19. Other embryonal tumors : ↑DWI ; ↓ADC Atypical Teratoid /Rhabdoid Tumors (AT/RT) • Heterogeneous tumour in children < 3 year-old, with aggressive radiological features. • Supra or infratentorial: predilection PCA • Frequent cysts, heamorrhages and dissemination
- 20. Warm-up case T2 ADC T2 ADC Patient 1 Patient 2 2.5 year-old 8 year-oldWNT (AT/RT)
- 21. Other embryonal tumors : ↑DWI ; ↓ADC Embryonal tumours with multilayered rosettes (ETMR) • Previously known as ETANTR or CNS PNET. • C19MC amplification • Children < 2 • Large mass with poor enhancement
- 22. PART 2: non-embryonal posterior fossa tumors in children Clint Eastwood et al. 1966
- 23. Pilocytic Astrocytoma • Slow growing tumour in the cerebellar hemisphere or brainstem. • Absence of relevant diffusion restriction • Marked enhancement and presence of cystic component
- 24. Pilocytic Astrocytoma - pitfalls Courtesy of Dr P. Hales ICH-UCL ↓DWI ; ↑ADC
- 25. Pilocytic Astrocytoma – Dissemination (< 10%)
- 26. Pilocytic Astrocytoma: Brainstem localisation : Medulla oblongata or midbrain
- 27. Diffuse Midline Glioma (DMG) -aka: Diffuse intrinsic pontine gliomas • Tumour centered in the pons which is expanded with effacement of the surrounding CSF spaces • Typical encasement of the basilar arteries • Usually do not enhance; localized areas of enhancement are possible • H3 K27 mutant, variable histology
- 29. Diffuse Midline Glioma (DMG) -enhancement and restriction
- 30. Diffuse Midline Glioma (DMG) -supratentorial and spinal locations Midline vs off-midline Patay Z. 2016
- 31. Ependymoma • Posterior fossa mass with plastic extension through the outlet foramina of the IV ventricle and ponto-cerebellar angle (toothpaste appearance). • Heterogeneous: calcium, haemorrhages, cysts (“the ugly”) • Generally ADC values are intermediate between PA and embryonal (areas of low ADC = anaplastic)
- 33. Supratentorial Ependymoma RELA fusion +
- 34. Pajtler et al. 2015
- 35. Pitfalls & Mimics Often streightforward … Pilocytic Astro arachnoid cyst
- 36. Tumour like lesion: resemble a tumour but is not… • Presence and pattern of enhancement • Mass effect • Infiltration • Edema • Signal characteristics
- 37. Tumour like lesion • Optic neuritis • Muscle weakness • Bladder problems • Complete recover NMO-SD ; MOG Ab + • Problems with eye movements • Facial drop DIPG • Optic glioma • Cafè-au-lait spots NF1 related FASI • Acute hearing impairment • Unilateral leg weakness and numbness Pontine stroke Don’t forget that you are clinical radiologists !!!
- 38. Case : 16 y M, high fever and cerebellar signs Muccio C, D’Arco F et al 2014
- 39. Case : 7 y, intractable vomiting. MRI shows brainstem lesion. Consideration for proton therapy Biopsy? Piloid gliosis, a type of chronic gliosis characterized by […] varying degrees of hypercellularity and glial atypia and associated with Rosenthal fibers, may be very difficult to distinguish from a monomorphous densely fibrillated PA. -Collins et al Acta Neuropathol 2015
- 40. “Given the radiographic findings in the setting of a prolonged clinical course and near normal neurologic examination, a diagnosis of low grade glioma was considered. However, the unusually symmetric appearance of the lesion prompted other “mutation analysis of the glial fibrillary acidic protein (GFAP) gene mutation was performed and ultimately revealed a novel pathogenic GFAP gene mutation”
- 41. Case : 7 y, mulifocal seizures TSC ! • Cerebellar tubers : 1/3 cases of TSC • Wedge shaped and folia distortion • Enhancement : 30% • Retraction of the cerebellar margin : 75% • 20% increase in size and enhancement overtime Daghistani R, Rutka J, Widjaja E. 2015
- 42. Case : 15 y, 2 wks history of fever, low back pain and focal seizures I am sure these are metastases ! TBC !
- 43. Companion Case : child from Egypt, ongoing treatment for TBC Diffuse leptomeningeal glioneuronal tumor
- 44. Case : 2 y, perinatal history of difficulty in swallowing Briguglio M, Pinelli L et al 2014 Pontine Tegmenta l Cap Dysplasia
- 45. WHO CNS 2016: A couple of tips… Removal of the term primitive neuroectodermal tumor or PNET: if C19MC- altered pathologist call them ETMR We should call them: “in keeping with embryonal tumour” Removal of the term Gliomatosi Cerebri (no longer an entity) We still use as a descriptive term representing a growth pattern found in many gliomas.
- 46. Take Home Messages New tumor classification including histological and molecular data Imaging can be used as a surrogate for molecular diagnosis Location – location –location ! (…but not only) Clinical context and careful analysis of image characteristics helps in DDX with tumor-like lesions
- 47. Acknowledgments • Dr. K. Mankad • Dr K. Chong • Dr. W. Jan • Dr. VH Marussi • Dr. U. Lobel
Editor's Notes
- Same image characteristics…. What about the location? Different right? These are exactly the same tumour.
- Despite similar location and appearances they are completely different
- different location…. Same imaging characteristics …they are in the same moment the same entity (medulloblastoma) and completeyl different tumors (two different subgroup with different prognosis)
- These examples are to show that in the last few years the classification of brain tumours become much more complicated buth also more precise, and you need to read papers on the new classification to have an overview.
- Let’s start with cerebellar embryonal tumours
- CT findings: Hyperdense mass in the posterior fossa (often in fourth ventricle), due to high cellularity (e-Figure 1). Possible presence of calcification/haemorrhages (1/5 of the cases) and small cystic/necrotic areas (up to half of the cases). Often associated with hydrocephalus Typical appearances in T2 (hypo) ADC (low values- restriction ) enhancement. We see something like that in the child and we think of Medulloblastoma… but the thinks are not so easy.
- 4 groups with different demographics, histology , progonsis and genetics …now can we distinguish groups using images…maybe yes…let’s start with something easy. As you can see an histological variant (desmoplastic / nodular) is always SHH subtypes so when we have typical nodular/desmoplastic appearance we are sure that this is a SHH….meaning good prognosis in infant and intermediate in older children…
- Remeber not all the SHH have nodular/desmoplastic appearance, but it is also peripheral
- different location…. Same imaging characteristics …they are in the same moment the same entity (medulloblastoma) and completeyl different tumors (two different subgroup with different prognosis)
- Why only 2/3 cases? Red: EGL
- Similar location but more heterogeneoity in comparison to WNT
- Despite similar location and appearances they are completely different
- Descrizione delle immagini
- Both are H3 K27 mutant, again is important location but the focus is not supra , infratentorial or brain vs spine but more midline vs off-midline
- We are not dealing with only one tumour this is just the tip of the iceberg
- stregithforward
- In questo caso le caratteristice di impregnazione , il poco effetto massa in confronto alla enorme
- abscess
- Alexander: c’e simmetria e non tanto effetto massa della lesione (nonostante enhancement). La testa del bambino e’ grande.. A volte anche una biopsia puo essere problematica ....
- Vomiting!!
- Tubero sclerosis cerebellar enhancement , Dale, Samuel
- 893205 she happened to do a plain film pre op : «There are multiple centrilobular lung parenchymal nodules with extensive infiltrate in the dependent pulmonary lobes tending to confluence in the dependent lung in keeping with haematogenous (miliary) infection. There is bilateral bibasal pleural change, in keeping with either pleural thickening or pleural fluid. There is a large pericardial fluid collection. The oesophagus is intimately involved with the para vertebral soft tissue mass and it would be important to assess the swallowing mechanism in this patient.”
- The same as disseminated oligodendroglial-like leptomeningeal tumor of childhood
- PTCD
- I hope I was more clear than that!