Embryonal Tumours(3)

8/14/2019 Embryonal Tumours(3)

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Ain Shams University

Faculty of Medicine

Pathology Department

2009/2010

Embryonic tumors

Names:

1- Ahmed Yaser 1520

2- Osama 1521

3- Eslam Mubarak Mohamed 1522

4- Asmaa Ahmed Mhmoud 1523


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Definition of Embryonic tumors

This broad group of childhood tumours crosses over the standard classification,

because embryonal tumours

They are characterised by the proliferation of tissue that is normally seen only in the

developing embryo. They are generally very rare after childhood, and occur most

commonly in the first few years of life. Several types of embryonal tumour have a

peak of incidence in the first year of life. Some types are occasionally found to be

present at birth.

They occur as:

1. Wilms tumour (nephroblastoma) in the kidney

2. retinoblastoma in the retina

3. hepatoblastoma in the liver

4. medulloblastoma in the cerebellum

5. neuroblastoma in the adrenal medulla

6. embryonal rhabdomyosarcoma in soft tissue

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Nephroblastoma "Wilms' tumour"

Definition:

Wilms' tumor is a rare kidney cancer that primarily affects children. Also known as

nephroblastoma, it's the most common malignant tumor of the kidneys in children.

The peak time of Wilms' tumor occurrence is around ages 3 to 4, and it occurs only

rarely after age 6.

Although Wilms' tumor can occur in both kidneys, it tends to affect just one kidney.

Wilms' tumor is believed to develop from immature kidney cells.

Improved imaging techniques help doctors to determine the extent of the cancer in

Wilms' tumor and to plan treatment. The outlook for most children with Wilms' tumor

is very good.

Gross picture:

synchronous or metachronous bilateral involvement in 510%

Usually:

o Solitary ,well circumscribed ,rounded ,soft consistency

Size variable (median 550 g)

Cut section:

o predominantly solid and pale gray or tan gray

o often cystic change, necrosis, and hemorrhage

Microscopic picture:

Three major components:

1. Blastematous areas:

o

extremely cellular& small round-to-oval primitive cellso cytoplasm usually scanty& sometimes oncocytoid appearance

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o growth pattern may be diffuse ,nodular ,cordlike (serpentine) or

basaloid (with peripheral palisading)

2. Mesenchymal elements:

usually a spindle cell fibroblast-like configuration may be differentiation toward various cell types, particularly smooth

and skeletal muscle

sometimes predominate almost to the exclusion of other components

3. Epithelial component:

embryonic tubular (and sometimes glomerular) structures that closely

recapitulate the appearance of normal developing metanephric tubules (and

glomeruli)

differentiation can be so pronounced that may be tumor analogs of

nearly all segments of normal nephron

these tubular structures can be small and round, simulating the rosettes

of neuroblastoma features favoring tubules over basal lamina are: A lumen, single cell

layer,distinct basal lamina &surrounding fibromyxoid stroma

exceptionally, marked hydropic changes in the tubular epithelium

o Papillonodular type grossly evident projections extend from the septa

into the cyst lumina &appearance on low power may be fibroadenoma like

o May be focal or extensive anaplastic features

o Possible additional features:ciliated, mucinous, squamous, or

transitional epithelium & renin-producing cells

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Diagnosis:

Several tests are used to confirm a Wilms tumor diagnosis and determine the stage of

the disease. Tests that might be used include:

Ultrasonography uses sound waves instead of X-rays to generate animage of the area doctors wish to view.

Computed tomography produces a detailed cross-sectional view of

an organ through X-rays

Magnetic resonance imaging (MRI) uses radio waves and strong

magnets to produce detailed pictures of the internal parts of the body.

X-rays are used to look for any metastasized areas, especially in the

lungs.

Bone scans use small amounts of radioactive material to highlight

areas of diseased bone.

Laboratory tests such as blood tests and urinalysis check the general

health of a patient and to detect any adverse side effects (such as low red or

white blood cell counts) of the treatment.

A physical examination. The doctor will look for possible signs of

Wilms' tumor.

Differential diagnosis: neuroblastoma - no triphasic patterns; has rosettes with no lumen, >1

cell layer, no distinct basal lamina, in contrast to Wilms immature tubules

which have a lumen, a single cell layer, distinct basal lamina and surrounding

fibromyxoid stroma perilobar nephrogenic rest - no fibrous capsule

renal cell carcinoma may resemble epithelial predominant Wilms

small blue cell tumors - if blastema predominates

Special Stains and Immunohistochemistry

Immunohistochemical profiles of various components mirror those of

their counterparts in the developing kidney, including highly specialized

compounds such as transport mediators

o

blastematous elements show only: focal positivity for vimentino epithelial elements react for :keratin ,EMA ,various lectins ,various

components of basement membrane

o mesenchymal elements show reactivity consonant with their

morphologic appearance such as: positivity for myogenin and desmin in

rhabdomyoblastomatous foci

o neural elements (when present) are reactive for: neuron-specific

enolase, glial fibrillary acidic protein, S-100 protein, Type I insulin-like

growth factor receptors:have been found & may be responsible for:

increased proliferation& inhibition of differentiation

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Retinoblastoma:

Definition:

Retinoblastoma (Rb) is a rapidly developing cancer which develops in the cells of the

retina, the light detecting tissue of the eye[1]. In the developed world, Rb has one of

the best cure rates of all childhood cancers (95-98%), with more than nine out of

every ten sufferers surviving into adulthood. Retinoblastoma is a very treatable

cancer.

Gross pictures-:In the gross pathology of the eye, we should comment of the following:

-The size of the tumour-The location of the tumour (endophytic or exophytic; single or multiple; any vitreal

seedings(

-Any spread outside the globe (especially of the optic nerve. In optic nerve

involvement, there may be abnormal optic nerve enlargement or tumour surrounding

the nerve. Extraocular spread is of great prognostic value

Microscopic pictures:Under the microscope, retinoblastoma contains deep blue cells with little cytoplasm.

As the tumour cells usually outgrow their blood supplies, necrosis and haemorrhage

are common within the tumour

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Diagnosis:-

Retinoblastoma can be diagnosed by an eye examination, supported by imaging

studies. There are no blood tests available to diagnose retinoblastoma.

The following tests and procedures may be used:

History: The doctor will first seek to know if there is a family history of

retinoblastoma.

A physical examination of the person will be carried to check for general signs of

disease.

An eye examination will be carried out on the person by dilating the pupils with

medicated drops to look at the retina through the lens and pupil. In the case of

children, this exam may be done under anesthesia.

Ultrasound examination may be carried

CT scan: This procedure is also called computerized tomography. Detailed pictures

of the inside of the eye can be taken, from different angles, to define the extent of the

tumor

Magnetic resonance imaging : This procedure, that uses a magnet, radio waves,

and a compute, is also used to make detailed pictures of the eye. This procedure is

also called nuclear magnetic resonance imaging (NMRI).

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A chest x-ray, bone marrow biopsy and/or a CT scan of the chest, may be carried

out. A biopsy is usually not required to diagnose retinoblastoma.

If the disease is extensive, a lumbar puncture is carried out to examine the

cerebrospinal fluid for the degree of damage

Hepatoblastoma

Definition:

Hepatoblastoma is the most common malignant liver tumor in early childhood. Mostpatients present before the age of 3 years with an enlarging asymptomatic abdominal

mass. Some patients have fever, pain, anorexia, and weight loss

Gross picture

On gross inspection, the epithelial type tends to be homogenous, while mixed

epithelial-mesenchymal tumors demonstrate a more variegated appearance with areas

of osteoid, cartilage, calcification, fibrosis, necrosis, and hemorrhage. The anaplastic

variant frequently contains a large focus of central necrosis. Microscopic vascular

invasion may be seen beyond an apparently encapsulated tumor

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Microscopic picture

Hepatoblastoma can be classified into a range of subgroups, although the prognosticsignificance of these are unclear : 75% are epithelial (fetal and embryonal types) and

the remainder are mixed epithelial or mesenchymal (figure 1). At the present time, no

stratification is made on the basis of pathology ; however, patients with pure fetal

histology, particulary those with small localised tumours may have a better outcome.

Diagnosis

In addition to a complete medical history and physical examination, diagnostic

procedures for hepatoblastoma may include:

Biopsy a sample of tissue is removed from the tumor and examined under a

microscope.

Complete blood count (CBC) a measurement of size, number and maturity

of different blood cells in a specific volume of blood.

Additional blood tests may include blood chemistries, evaluation of liver

and kidney functions and genetic studies.

Multiple imaging studies, including:

o Computed tomography scanuses a combination of X-rays and

computer technology to produce cross-sectional images, both

horizontally and vertically, of the body. A CT scan shows detailed

images of any part of the body, including the bones, muscles, fat and

organs. CT scans are more detailed than general X-rays.

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o Magnetic resonance imaging (MRI) uses a combination of large

magnets, radio frequencies and a computer to produce detailed images of

organs and structures within the body.

o X-ray uses invisible electromagnetic energy beams to produce

images of internal tissues, bones and organs onto film.

o Ultrasounduses high-frequency sound waves and a computer to

create images of blood vessels, tissues and organs. Ultrasounds are used

to view internal organs as they function and to assess blood flow through

various vessels.

o Bone scans pictures or X-rays taken of the bone after a dye has been

injected that is absorbed by bone tissue. These are used to detect tumors

and bone abnormalities.

Alpha-fetoprotein test alpha-fetoprotein levels in the blood

Recurrent the disease has returned after it has been treated. It may come

back in the liver or in another part of the body.

References

www.cancer.gov

http://medsavailable.com

http://www.pathconsultddx.com

http://peir2.path.uab.edu

http://www.wikipedia.org

http://emedicine.medscape.com

http://www.md.ucl.ac.be/pedihepa/Liver%20tumours.htm

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http://www.cancer.gov/http://medsavailable.com/http://www.pathconsultddx.com/http://peir2.path.uab.edu/http://www.wikipedia.org/http://emedicine.medscape.com/http://www.md.ucl.ac.be/pedihepa/Liver%20tumours.htmhttp://www.cancer.gov/http://medsavailable.com/http://www.pathconsultddx.com/http://peir2.path.uab.edu/http://www.wikipedia.org/http://emedicine.medscape.com/http://www.md.ucl.ac.be/pedihepa/Liver%20tumours.htm


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Embryonal Tumours(3)