CNS Malignancies Year 4 Paediatrics Notes OmpathStudy

CNS Malignancies Year 4 · Paediatrics Collection: 4TH YEAR ALL NOTES / PAEDS / PAEDS 4.3 / Munge / ONCOLOGY -- Slide 1 CNS Malignancies Dr Rose Munge Slide 2 Outline Introduction Incidence Risk factors Classification Clinical picture Diagnosis and Treatment Prognosis Slide 3 Introduction Brain tumors are either primary or secondary. Primary brain tumors arise from different cells of the CNS.\nPrimary brain tumors are diagnosed in approximately 52,000 people each year in the United States. At least one-half of these tumors are malignant and associated with a high mortality rate.\nGlial tumors account for about 60% of all primary brain tumors, and 80% of those are malignant neoplasms.\nMeningiomas account for 25%, vestibular schwannomas 10%, and central nervous system (CNS) lymphomas about 2%. Slide 4 Incidence CBTRUS: The incidence rate of all primary malignant and non-malignant brain and CNS tumors is 20.6 cases per 100,000 (7.3 per 100,000 for malignant tumors and 13.3 per 100,000 for non–malignant tumors). The rate is higher in females (22.3 per 100,000) than males (18.8 per 100,000). Slide 5 IARC: The worldwide incidence rate of primary malignant brain and CNS in 2008, age–adjusted using the world standard population, was 3.8 per 100,000 in males and 3.1 per 100,000 in females.\nThe incidence rates were higher in more developed countries (males: 5.8 per 100,000; females: 4.4 per 100,000) than in less developed countries (males: 3.2 per 100,000; females: 2.8 per 100,000). Slide 6 CBTRUS: The incidence rate of childhood primary malignant and non–malignant brain and CNS tumors is 5.1 cases per 100,000. The rate is higher in males (5.2 per 100,000) than females (5.1 per 100,000). Slide 7 Children 80% of pediatric tumors are-juvenile pilocytic astrocytoma, medulloblastoma/primitive neuroectodermal tumor [PNET], diffuse astrocytomas, ependymoma, and craniopharyngioma There is slight predominance of infratentorial tumor location (43.2%), followed by the supratentorial location (40.9%), spinal cord (4.9%), and multiple sites (11%). Slide 8 In infants- supratentorial tumors predominate, most commonly, choroid plexus complex tumors and teratomas. \n1-10 yrs- infratentorial tumors predominate, owing to the high incidence of juvenile pilocytic astrocytoma and medulloblastoma.\nAfter 10 yr of age-supratentorial tumors predominate, diffuse astrocytomas most common.\nTumors of the optic pathway and hypothalamus region, the brainstem, and pineal-midbrain region occur with a greater incidence in children and adolescents than in adults Slide 9 Brain metastases are three times more common than all primary brain tumors combined and are diagnosed in approximately 150,000 people each year.\nMetastases to the leptomeninges and epidural space of the spinal cord each occur in approximately 3–5% of patients with systemic cancer and are also a major cause of neurologic disability in this population.\nLung cancer, melanoma, renal cell carcinoma, and breast cancer are the most common primary tumors that metastasize to the brain. There is evidence of an increasing incidence of CNS tumors in the last 50yrs. Slide 10 Risk Factors No underlying cause has been identified for the majority of primary brain tumors.\nThe only established risk factors are exposure to ionizing radiation (meningiomas, gliomas, and schwannomas) and immunosuppression (primary CNS lymphoma).\nEvidence for an association with exposure to electromagnetic fields including cellular telephones, head injury, foods containing N-nitroso compounds, or occupational risk factors, are unproven.\nA small minority of patients have a family history of brain tumors. Some of these familial cases are associated with genetic syndromes Slide 11 Genetic associations NF-1 (von Recklinghausen) NF-2 gene deletion @ 22 (schwannomas) VHL - capillary haemangioblastoma TSC - subependymal giant cell astrocytoma Li-Fraumeni Syndrome Cowden disease Turcot syndrome Nevoid basal cell carcinoma syndrome Slide 12 Classification 1. Tumours of neuroepithelial tissue\n2. Tumours of cranial and paraspinal nerves 3. Tumours of the meninges 4. Tumors of the haematopoietic system 5. Germ cell tumours 6. Tumours of the sellar region 7. Metastatic Tumours Slide 13 Can also be classified into intrinsic malignant tumors and\n-extrinsic benign tumors Slide 15 supratentorial infratentorial Choroid plexus tumours Teratoma astrocytoma Medulloblastoma Cerebella astrocytoma Ependymoma craniopharyngioma Slide 16 Histopathologic classification Classified by light microscopy according to predominant cell type and graded. Gliomas-80% of primary cns malignancies.-astrocytomas,oligodendrogliomas.\nAre diffusely infiltrative tumors-invade the parenchyma Slide 17 Gliomas Astrocytes are glial cells that help nourish neurons– they help repair damage.\nHigh grade Low grade: commonest; juvenile pilocytic astrocytoma(cerebellum) OLIGODENDROMAS Oligodendrocytes make myelin which help neurons transmit signals through the axons\nT