Pediatric Tumors Flashcards
1
Q
Epidemiology
A
2
Q
Leukemia
A
- Most common malignancy in childhood
-
Most common type is ALL (80% of childhood leukemia)
- Most are B-cell leukemias
- There is a T-cell leukemia (lymphoblastic)
- Commonly seen in adolescent males
- Presents with a mediastinal mass
- Chromosomal abnormalities ⇒ seen in many types
- Trisomy 21 ⇒ high rate of acute leukemia
3
Q
Lymphoma
A
- Hodgkin’s Disease uncommon in children
- Non-Hodgkin’s Lymphoma
- Burkitts lymphoma
- In Africa they present in the jaw
- Here they present in the abdomen
- B-cell in origin
4
Q
Langerhans Cell Histiocytosis
A
- Affects the lungs, liver, or hematopoietic system
- Excess immature Langerhans cells form tumors called Eosinophilic Granulomas
- Also known as pulmonary histiocytosis X (PHX)
-
Letterer-Siwe disease
- One of the four recognized clinical syndromes of LCH
- Causes ~ 10% of LCH disease
- Most severe form
- Langerhans cells contain Birbeck granules
5
Q
Medulloblastoma
A
- Type of embryonal neuroendocrine tumor
- Most common type of malignant brain tumor in children
- Usually occur in the cerebellum
6
Q
Astrocytomas
A
- Originates from astrocytes
- Can form in the brain or spinal cord
- Usually benign in children
- Malignant Astrocytoma and Glioblastoma multiforme are VERY RARE in children
7
Q
Ependymomas
A
- Malignant tumors originating from ependymal cells
- Found in the brain or any part of the spine
- Can be seen in children and are likely to come back after tx
8
Q
Craniopharyngiomas
A
- Derived from Rathke’s pouch up near the pituitary
- Difficult to remove
9
Q
Pinealoblastoma
A
- Pineal gland tumor
- Poor prognosis
10
Q
Pituitary Tumors
A
Pituitary adenomas and meningiomas are rare in children
11
Q
Neuroblastoma
Overview
A
- 2nd most common solid tumor in children
- Usually arise in the adrenal medulla
- Location in the adrenal is worse than locations elsewhere
- Can also be seen in the sympathetic ganglion ⇒ paraganglioma
- Typically occurs in the posterior mediastinum
- Tumors secrete catecholamines
- Especially Homovanillic Acid (HVA)
- Worse to get the tumor as an older child (4‐5 y/o)
12
Q
Neuroblastoma
Progression
A
- A malignant neuroblastoma can mature into a benign tumor
- First into a ganglioneuroblastoma
- Then into a ganglioneuroma
13
Q
Neuroblastoma
Histology
A
Small round blue cells that often form rosettes
14
Q
Neuroblastoma
Genetics
A
- Neuroblastomas can be congenital
- Two‐hit hypothesis
- Two mutations involved in development of this tumor
- Deletion of the short arm of chromosome 1
- Amplification of the gene N‐myc
- AD pattern of susceptibility to neuroblastomas
15
Q
Wilms’ Tumor
Overview
A
- “Mesoblastic Nephroma”
- Most common intra-abdominal tumor in children
- This tumor tries to make a kidney
- Demonstrates the two-hit hypothesis
16
Q
Wilms’ Tumor
Histology
A
- Primitive tubules form along with a mesenchymal component
- Nodular renal blastema is also seen
- Primitive undifferentiated cells
- Thought to be a remnant of kidney formation
17
Q
Wilms’ Tumor
Treatment and Prognosis
A
- Kidney is removed
- Patient goes through chemotherapy and radiation therapy
- 2-year survival between stages I to III is between 80-90%
- Prognosis ‐ the younger the better
18
Q
Wilms’ Tumor
Associated Syndromes
A
- 13-15% are associated with other congenital abnormalities, esp. GU anomalies
- Can be a part of Denys-Drash syndrome
- Kidney disease present at birth, Wilms tumor, and malformation of the sexual organs
-
Beckwith Wiedemann Syndrome can be seen in these children
- Hemihypertrophy, omphalocele, large tongue
- This is an equivalent of a first hit
- Can see aniridia with Wilms ⇒ absence of the iris, usually involving both eyes
- Have chromosomal deletion of gene on P arm of Chromosome 11
- Can be associated with the WAGR complex
- Wilms’ Tumor-Aniridia-Genitourinary Anomalies-Mental Retardation Syndrome
19
Q
Rhabdomyosarcoma
Overview
A
- Most common soft tissue neoplasm in children
- Derived from skeletal muscle
- Cells w/ abundant eosinophilic striated cytoplasm
- Immunohistochemistry used to ensure origin
- Muscle specific actin ⊕
- Desmin ⊕
20
Q
Alveolar Rhabdomyosarcoma
(ARMS)
A
- Involves a t(2;13) translocation
- Makes up a larger portion of RMS in older children, teens, and adults than in younger children
- Most often occurs in large muscles of the trunk, arms, and legs
21
Q
Sarcoma Botryoides
A
- Embryonal form of rhabdomyosarcoma
- Found in the walls of hollow, mucosa lined structures
- Looks like a grape‐like mass protruding through the vagina of a little girl
- Great strides have been made in the treatment of this tumor
22
Q
Hemangiomas
A
- Benign tumors of blood vessels
- Common in children
- Can spontaneously regress
- Malignant form is an angiosarcoma
23
Q
Osteogenic Sarcoma
A
- Most common in adolescents
- Distal femur and proximal tibia are common locations
24
Q
Ewing’s Sarcoma
A
Small round blue cell tumor
25
**Teratomas**
* Germ Cell Tumors
* Can be located in the ovaries, mediastinum, or sacrococcygeal area
* Composed of tissue from different germ layers
* Usually benign in the **cystic form**
* Maturity of tissues involved in the teratoma determines benign vs malignant
* Immature teratomas of the ovaries are usually seen in children as opposed to adults
26
**Endodermal Sinus Tumor**
* “Yolk sac tumor”
* Most common malignant neoplasm in the infant testis
* Secretes AFP
27
**Testicular**
**Germ Cell Neoplasms**
* **Embryonal carcinoma**
* Non-seminomatous germ cell tumor (NSGCT)
* Tends to grow rapidly and spread outside the testicle
* **Choriocarcinoma**
* Non-seminomatous germ cell tumor (NSGCT)
* Rarest and most aggressive form of testicular cancer
* **Secretes Beta HCG**
28
**Retinoblastoma**
* Used to derive the two-hit hypothesis
* Most cases are sporadic, not hereditary
* **RB1 gene (retinoblastoma suppressor gene) located on Chromosome 13**
* Diagnosed by seeing leukocoria (white pupil)
* Treatment usually necessitates enucleation of the eye
29
Genetic Associations
