Module 8:PEDS: Neoplasms Flashcards
What are the common malignant neoplasms in 0-4 yr olds?
Leukemia Retinoblastoma Neuroblastoma Wilm's Tumor Hepatoblastoma Soft Tissue Sarcoma Teratoma CNS tumor
What are the common malignant neoplasms in 5-9 yr olds?
Leukemia Retinoblastoma Neuroblastoma Hepatocellular carcinoma Soft tissue sarcoma Ewing tumor CNS tumor Lymphoma
What are the common malignant neoplasms in 10-14 yr olds?
Heptocellular Carcinoma Soft tissue sarcoma Osteogenic sarcome Thyroid carcinoma Hodgkin disease
What are some general features of pediatric neoplasms?
Magnitude of pediatric malignancy is much lower than in adult
- most pediatric tumors are embryonal, not carcinomas
- -pediatric tumors dont occur in the same location as adult tumors
- -pediatric tumors are more responsive to therapy
- -better prognosis and survival rate than adults
What are the predisposing factors for pediatric neoplasms?
Down syndrome and agammaglobulinemia
Deletion 13q (retinoblastoma)
Wiskott Aldrich Syndrome (lymphoma)
What are the tumors of embryonal origin?
Small, round, blue cell tumors
- lymphoma/leukemia
- medulloblastoma
- -neuroblastoma
- -rhabdomyosarcoma (embryonal and alveolar)
- wilms tumor
- bone tumors (ewings sarcoma and small cell osteosarcoma)
What is the origin of neuroblastoma?
Poorly differentiated tumor of NCC that normally give rise to the adrenal medulla and sympathetic due to germline mutation in ALK gene
–second most common malignant tumor in kids
What is the presentation for neuroblastoma?
less than 2 years old: mass in abdomen or mediastinum, fever or weight loss
Older children: signs of metastatic disease (bone pain, resp and GI symptoms)
Blueberry Muffin baby: disseminated neuroblastoma
What investigations are done for neuroblastoma?
Gross: calcification in 40-50%
Microscopy: neurophil (eosinophilic fibrillary material) and Homer-Wright Pseudorosettes (tumor cells arrange around neurophil without a lumen)
EM: neurosecretory granules
IHC: neuron-specific enolase and synaptophysin
What confirms diagnosis of neuroblastoma?
Increased blood catecholamines
Increased urine levels of catecholamines (VMA and HVA)
MIBG scintigraphy: concentrates over 90% of tumors – used for assessment of spread and response to therapy
What are the good and poor prognostic factors for neuroblastoma?
Good: stage 4S and increased expression of tyrosine kinase receptor A
Poor: deletion distal 1p and gain of distal 17q; n-myc amplification and telomerase overexpression
Moving on to nephroblastoma (Wilm’s Tumor), what is this?
Malignant embryonal neoplasm from nephrogenic blastemal cells
–most common primary renal tumor of childhood
What are the various etiologies for Wilm’s Tumor?
Most cases are sporadic 10% are associated with: --WAGR syndrome: WT-1 gene mutation --Denys-Drash syndrome: WT-1 gene mutation -Beckwith-Wiedemann syndrome -Mutations of Beta-Catenin Gene
What is the precursor lesion for Wilm’s Tumor?
Nephrogenic rests
What is presentation for Wilm’s Tumor?
Detection of abdominal mass by parent while bathing the child
What is seen on histology for Wilm’s Tumor?
Triphasic pattern due to divergent differentiation
- -blastema: sheets of small round blue cells
- stroma: myxoid
- epithelium: abortive tubules and glomeruli
What are complications of Wilm’s Tumor?
Restricted pattern of metastasis = regional LNs, lungs and liver
What is the anaplastic subtype of Wilm’s Tumor?
5% of cases: characterized by hyperchromatic nuclei with greater than 3 times larger than those in adjacent cells
–correlates with acquired TP53 mutations
Next is retinoblastoma, what is the etiology?
Malignant neoplasm arising from retina
–40% congenital: RB1 gene: multiple, bilateral tumors
(increased susceptibility to other malignant tumors: osteogenic sarcoma, Ewing’s sarcoma, pinealoblastoma)
–60% sporadic: unifocal and unilateral tumors
What is the presentation for retinoblastoma?
Leukocoria Strabismus Poor Vision Spontaneous Hyphema Red and Painful eye
What is found on histology for retinoblastoma?
Flexner-Wintersteiner Rosettes: clusters of cuboidal cells arranged around a central lumen
What are complications of retinoblastoma?
Extension into optic nerve and/or subarachnoid space with intracranial spread
Invasion of blood vessels
Secondary Glaucoma
Finally where do teratomas arise from?
Most arise in the sacro-coccygeal region
–other sites = testes and ovaries
What is the prognosis for teratomas?
Less than 4 months = benign
1 year = 50% malignant
5 years = 100% malignant
–proportion of immature elements is important in gauging degree of malignant potential
