childhood cancers
TRANSCRIPT
Belgorod State National Research University
Department: Pathological Anatomy.
Topic: Childhood Tumors.
Compiled by:
N. K. Gaur
Small,Round, Blue Cell Tumors in Childhood.
Primitive appearance (not anaplastic or pleomorphic)
Sheets of small,round,blue cells (with dark nuclei,scant
cytoplasm,indistinct borders.)
May show features of organogenesis specific to the tissue
of origin.
Neuroblastoma
Embryonal malignant tumour
Neural crest origin
Neoplastic neuroblasts
Site: adrenal medulla &sympathetic ganglia
7-10% of solid paediatric malignancies.
Sporadic occurance.
Rarely familial (bilateral,multifocal)
Pathology of Neuroblastoma.
Site :Paravertebral, Posterior mediastinum, abdomen ,Adrenal
1/3
Gross appearance:
Nodular, of varying size
May be encapsulated or infiltrative
Cut section: grey-tan, soft and friable
Varigated, necrosis, hemorrhage, calcification, cystic change
Microscopy of Neuroblastoma
Sheets of small, round, blue cells with dark nuclei, scant cytoplasm,
indistinct borders.
Mitosis++, Karyorrhectic debris +
Pleomorphism +/-
Homer-Wright rosettes, Neuropil.
Maturation: Schwann cell, stroma &ganglion cell differentiation.
Clinical features.
Abdominal mass, fever
Blueberry muffin
Wide metastasis
Secrete catecholamines
Vanillylmandelic acid (VMA)/Homovanillic acid (HVA) screening.
Prognosis
Stage
spread to regional lymph nodes,liver,lungs,bones etc
Age :< 1 yr.
Morphology –gangliocytic differentiation better
MYCN (N myc) gene amplification-worse.
Retinoblastoma
Malignant tumour of the eye in childhood
Neuroepithelial origin –posterior retina
Familial,- 60-70%, associated with germ line mutation, heritable.
Sporadic:30-40%,somatic gene mutation.
Associated with Rb 1 gene
Secondary malignancy –osteosarcoma
RB gene
RB gene is on chromosome 13
RB gene function is the most critical checkpoint in the cell cycle and allows the cell to enter from
G1 to S
Tumour supressor gene
If both RB genes are abnormal i.e. mutated or have a missing allele, it permits unregulated cell proliferation.
Knudson’s two-hit hypothesis
People with RB mutations are susceptibe to malignancies especially osteosarcoma
Morphology of retinoblastoma.
Gross: occular masses.
Microscopy: Sheets of small,round,blue cells with dark nuclei,scant
cytoplasm,indistinct borders
Flexner-Wintersteiner rosettes.
Behaviour .
Spread through optic nerve or to subarachnoid space to CNS, bone,
lymph nodes.
Cure with treatment.
Spontaneous cure.
Second malignancy.