Paediatric Tumours

1. PaediatricTumours Dr Malith Kumarasinghe MBBS (Colombo)

2. Pediatric Neurosurgical Neuropathology • Brain tumors are second only to leukemias in children • Brain tumors are the most common solid organ tumor in children • 70% of pediatric brain tumors are in the posterior fossa • Pilocytic astrocytoma • Medulloblastoma • Ependymoma

3. CNS tumors: pediatric vs. adult • Adults: 70% of tumors are supratentorial • meningioma • pituitary adenoma • High grade astrocytoma • Anaplasticastrocytoma (grade III) • Glioblastomamultiforme (grade IV astrocytoma) • Pediatric: 70% in posterior fossa • pilocyticastrocytoma (cerebellarastrocytoma) • medulloblastoma

4. Brain tumors: intro • Intracranial neoplasms • Primary • Secondary • Metastatic • Local invasion • Tumors of the spinal cord

5. Primary brain tumors: intro • Primary brain tumors are rare • 2.5% of all cancer deaths • Second most common type of tumor in children • There are over 100 different brain tumors • Most common types • Astrocytomas • Grades I-IV • Medulloblastomas • primitive neuroectodermal tumor-PNET • Meningiomas • Pituitary adenomas

6. Clinical presentation • Clinical symptoms depend upon: • Age, location, and type of tumor and grade • Symptoms may include: • Increased intracranial pressure • secondary to obstruction of CSF at aqueduct • hydrocephalus (infants), headache, papilledema, vomiting • seizures • focal neurological deficits • hormonal changes (pituitary adenoma) • visual changes (diplopia, field defects) • Pituitary adenoma - pressure on optic chiasm

7. CNS tumors: diagnosis • Symptoms prompt neuroimaging • CT and MRI • intra-axial vs. extra-axial • Location of tumor • contrast enhancement • typical of high grade • also in some low grade, i.e., pilocytic astrocytomas

8. CNS tumors: location • Extra-axial • meningiomas • Cerebral hemispheres • grade II-III astrocytomas, GBM • Crossing corpus callosum - GBM • optic nerve - pilocytic astrocytoma (NF-1) • Sella - Pituitary adenoma • Peri-III ventricle - Pilocytic astrocytoma, GBM

9. CNS tumors: location • posterior fossa (in children) • pilocytic astrocytoma • medulloblastoma • brainstem (pons) • pontine glioma (astrocytoma) • spinal cord • low-grade astrocytomas (grade I and II)

10. Pilocytic astrocytomas • Most common in children • Grade I astrocytoma • Cerebellum (posterior fossa), optic nerve • Thalamic, spinal cord, cerebral • Discrete, well circumscribed mass • Often with associated cystic area • Contrast enhancing • Histologic appearance: • Biphasic: piloid cells and microcystic areas • Rosenthal fibers • no mitoses

11. Pilocytic astrocytomas Tumor of cerebellum, often with cyst, biphasic, Rosenthal fibers, piloid cells

12. Astrocytoma - high grade • Astrocytoma grade II and III are very, very rare in the pediatric population • Grade IV - glioblastoma multiforme • Diffusely infiltrating glial tumor of cerebral hemispheres • Contrast enhancing tumor • Histological appearance: • Densely cellular, with marked nuclear pleomorphism • Numerous mitoses • Endothelial proliferation • Necrosis with pseudopallisading

13. Glioblastoma (grade IV) • Less common in children than adults, typical pathology (necrosis with psuedopallisading)

14. Pontine glioma Diffuse expansion of pons, usually high grade astrocytoma (III-IV)

15. Medulloblastomas • posterior fossa in children • Histologic appearance: • Densely cellular “small blue cell tumor” • Numerous mitoses • Apoptotic (karyorrhectic) cells • Endothelial proliferation • Necrosis • neuronal or glial differentiation • Homer Wright rosettes • GFAP positive cells

16. Medulloblastoma • Mass arising in roof of fourth ventricle • Homer Wright rosettes

17. Ependymoma • Mass arising in floor of fourth ventricle • Perivascular pseudorosettes

18. Meningiomas • Discrete non-invasive tumor • Extra-axial, pushes into brain • Attached to dura • Hyperostosis or invasion of skull common • Histologic appearance: • Fibroblastic or menigothelial cells • Meningothelial whorls • Psammoma bodies • Rare in children, may be intraventricular (lateral ventricles)

19. Meningiomas Extra-axial tumor, meningothelial cells, whorls and psammoma bodies

20. Ganglioglioma Cerebrum, cervicomedullary, often with cystic component Increased numbers of neurons (some binucleate) and increased glial cells (usually astrocytic)

21. Craniopharyngioma • Heterogeneous, cystic mass in suprasellar region • Basiloid layer, stellate reticulum, “wet” keratin, often calcified

22. Choroid plexus papilloma • Lateral ventricle in children (fourth ventricle in adults)

23. Germ cell tumors Germinoma Teratoma • Pineal - 99% males, most are germinomas • Suprasellar - often mixed germ cell tumor, 50% female • Tertomas are rare

24. Metastatic tumors • The most common “brain” tumor in adults is metastatic • Metastatic tumors are rare in children • The most common metastatic tumor in children is osteosarcoma • Local extension of malignant tumors of vertebral bodies (Ewing’s sarcoma) or paravertebral soft tissues (neuroblastoma) are not uncommon

25. Other tumors • Subependymal giant cell astrocytoma (SEGA) • Intraventricular tumor in Tuberous sclerosis • Desmoplastic infantile ganglioglioma (DIG) • Superficial cerebral tumor in infants • Dysembryoplastic neuroepithelial tumor (DNET) • Hamartomatous lesion associated with seizures • Atypical teratoid rhabdoid tumor (ATR, AT/RT) • Infants, posterior fossa, very malignant • Eosinophilic granuloma • A type of Langerhans cell histiocytosis • Single discrete osteolytic lesion in skull • Meningioangiomatosis • Hamartomatous superficial cerebral lesion associated with seizures

26. Hereditary syndromes • Neurofibromatosis type I • Café-au-lait spots • Dermatofibromas, multiple • optic nerve gliomas, bilateral • plexiform neurofibroma • Malignant peripheral nerve sheath tumor • Neurofibromatosis type II • bilateral acoustic neuroma • multiple meningiomas • ependymomas

27. 􀂄 Most intraspinal tumors present by compression rather than invasion

28. Compression Syndromes 􀂄 Root– severe, sharp, shooting pain with weakness or numbness in distribution of root (radicular) 􀂄 Bone– continuous dull pain and tenderness– may not be relieved by rest

29. Compression Syndromes􀂄 Anterior– bilateral weakness, dissociated sensory loss(loss of pain and temperature, retainedposition sense, pressure, vibration)􀂄 Posterior– rare, produces paresthesias, impairedposterior column function

35. Compression Syndromes 􀂄 Lateral – aka Brown Sequard – contralateral loss of pain and temperature 1-2 segments below injury – ipsilateral loss of posterior column function and weakness – best prognosis of any spinal cord syndrome

37. Compression Syndromes 􀂄 Central – weakness of UE > LE – “cape-like” sensory deficit

38. Location 􀂄 Extradural (ED) 􀂄 Intradural Extramedullary (IDEM) 􀂄 Intramedullary (IM)

39. Extradural Tumors 􀂄 55% of spine tumors 􀂄 tissues: bone, epidural fat, vessels 􀂄 majority are metastatic 􀂄 “feathered”appearance on myelogram

40. Extradural Tumors • Metastatic – usually cause bone destruction – include lung, lymphoma, breast, and prostate (last two may be osteoblastic) • Tumors with both ED and ID potential – meningiomas (15% are wholly extradural) – neurofibromas

41. Spine Based Tumors 􀂄 Benign – hemangioma, osteoidosteoma,osteoblastoma, osteochondroma, giant cell tumors, eosinophilicgranulomas, aneurysmalbone cysts 􀂄 Malignant – chordoma, osteosarcoma, chondrosarcoma, fibrosarcoma, Ewing’s sarcoma, multiple myeloma, lymphoma, neuroblastoma, mets

42. Extradural Tumors 􀂄 Chloromas – focal infiltrate of leukemic cells 􀂄 Angiolipomas – very rare (60 cases in literature) 􀂄 Spine based tumors

43. IntraduralExtramedullary 􀂄 40% of spinal tumors 􀂄 tissues: nerve roots, meninges, CSF 􀂄 4% of spinal metastatic lesions 􀂄 sharp meniscus on myelogram

44. IntraduralExtramedullary 􀂄 Nerve Sheath Tumors – Schwannomas, Neurofibromas, Ganglioneuroma, Neurofibrosarcoma 􀂄 Meningiomas 􀂄 Lipomas 􀂄 mets

45. Intramedullary 􀂄 Ependymoma, 30% 􀂄 Astrocytoma, 30% 􀂄 Misc, 30% – rare: GBM, dermoid, epidermoid, teratoma, lipoma, hemagioblastoma – very rare: neuroma, mets – extremely rare: cholesteatoma, oligodendroglioma, lymphoma

46. Treatment • Surgery recommended for benign and malignant primary spinal cord tumors, the role of surgery in spinal metastasis, or cancer that has spread to the spine, is controversial. Recent developments in imaging as well as new surgical tools and techniques, such as ultrasonic aspirators and lasers, have significantly expanded the role of surgery as an intervention.

47. For metastatic tumors with spinal cord compression, some neurosurgeons may perform surgery in selected patients to relieve pressure and pain, reconstruct or stabilize the spine, preserve mobility and bowel and bladder function, and to maximize quality of life. • Some doctors may only recommend surgery for patients with a single metastatic tumor and no evidence of cancer growing at another site.

48. Radiation Therapy • Most patients with primary spinal cord tumors will not require radiation therapy. • Radiation, however, is used to treat spinal cord compression due to metastatic cancer or cancer that has spread from other locations. • Other targets of radiation include some primary cancers of the spine and more rarely, benign or low-grade spinal cord tumors that cannot be completely removed surgically.

49. Chemotherapy Chemotherapy, may be recommended in adults for spinal gliomas that progress after surgery and radiation.

50. Thank you