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Answer: Phalangeal Ewing's tumour
Ewing's sarcoma
Also known as:
Ewing's angioendothelioma
Ewing's endothelial sarcoma
Ewing’s syndrome
Ewing’s tumour
Synonyms:
Diffuse bone endothelioma, endothelial myeloma, endothelial sarcoma, omoblastoma,
roundcell sarcoma.
Associated persons:
James
Ewing (American pathologist, born December 25, 1866, Pittsburgh,
Pennsylvania; died May 16, 1943, New York.)
Description:
A primary tumour in the bone that may occur in any bone but is most prevalent in
the shafts of the long bones of the lower extremities, never in the growth
joints, and never exhibiting osteoblastic properties. Intermittent pain in any
bone, most frequently the jaws, shafts of long bone and pelvis, increasing with
progress of disease. The skull, clavicle, ribs, and shoulder and pelvic girdles
may be involved. Slight fever. The tumour is composed of compact, uniform cells
with large, round, or ovoid nuclei containing scattered chromatin. Mitotic
changes are common; small vascular channels may be present.
The sarcoma is very destructive and soon will spread to other parts of the body.
Even with radical treatment the death rate is very high. Most commonly affected
are children, adolescents, and young adults. Ewing's sarcoma accounts for 10-15%
of all primary malignant bone tumours. Incidence is about 0.6 per million, less
common in black and Chinese populations. Te origin of Ewing's Tumour still
remains unclear.
Similar tumours had been reported earlier by Georg Albert Luecke in 1866 and
Otto Hildebrand (1858-1927) in 1890, but it was the work of Ewing which
established that the disease was separate from lymphoma or neuroblastoma.
Ewing's first paper on "his" sarcoma was first presented at a meeting
of the New York Pathological Society in 1920.
Bibliography:
Ewing's
sarcoma is a highly malignant tumor that is a type of peripheral primitive
neuroectodermal tumor (PNET). Ewing's sarcoma is found in the lower extremity
more than the upper extremity, but any long tubular bone may be affected. The
most common sites are the metaphysis and diaphysis of the femur followed by the
tibia and humerus. Ewing's sarcoma is most common in the first and second decade
but may affect persons from age 2 to 80. This tumor preferentially
affects whites more than blacks and Asians. The ratio of male to female is 3:2.
The clinical presentation of Ewing's sarcoma includes
pain and swelling of weeks or months duration. Erythema and warmth of the local
area are sometimes seen. Osteomyelitis is often the initial diagnosis based on
intermittent fevers, leukocytosis, anemia and an increased ESR.
Radiologically, Ewing's sarcoma is often associated
with a lamellated or "onion skin" periosteal reaction. This appearance
is caused by and splitting and thickening of the cortex by tumor cells. The
lesion is usually lytic and central. Endosteal scalloping is often present. The
"onion-skin" appearance is often followed with a
"moth-eaten" or mottled appearance and extension into soft tissue. .
Bone marrow infiltration is not obvious on plain x-ray. While Ewing's sarcoma is
usually lytic it may present as a sclerotic lesion with bone expansion. CT is
helpful in defining bone destruction. MRI is essential to elucidate the soft
tissue involvement because with TI-weighted images the tumor has low intensity
compared to the normal high intensity of bone marrow. On :1 2 -weighted images
the tumor is hyper intense compared to muscle. Ewing's sarcoma has increased
uptake on bone scan.
Grossly, the tumor is gray to white in color and poorly
demarcated. The consistency is soft and gray and sometimes semi-liquid
especially after breaking through the cortex. Areas of hemorrhage and necrosis
are common. The destruction is often greater on gross appearance than was
visible on
radiographs.Under the microscope, Ewing's sarcoma consists of densely packed
uniform small cells in sheets. The cells have scant cytoplasm without distinct
borders. The cells are two to three times as big as lymphocytes and have a
single oval or round nucleus without prominent nucleoli. The tumor spreads
through Haversian canals which cause the appearance of permeative margins on
x-ray. Glycogen is present within the cells causing a positive reaction to
periodic acid-schiff (PAS) stain. Most Ewing's sarcomas are positive with HBA-71
or 0-13 stain which is an antibody to the protein product of myc 2. The
microscopic differential includes lymphoma and metastatic neuroblastoma which
must be excluded by reticulin stain and urine vanillyl mandelic acid and
homovanillic acid respectively. Rhabdomyosarcoma is ruled out if the specimen
stains negatively with desmin, myoglobin and actin stains.A neural origin is
supported by electron microscope findings of pseudorosettes. This is further
supported by the common finding in Ewing's sarcoma and primitive neuroectodermal
tumors of choline acetyltransferase and the translocation t(11:22)(q24;ql2). It
is thought that Ewing's sarcoma with its few organelles is the poorly
differentiated end of the spectrum of PNET. Neuroepithelioma is an example of
well differentiated PNET and has neurosecretory granules and neuritic processes.
Treatment for Ewing's sarcoma includes surgery,
radiation and multi-drug chemotherapy. Radiation or chemotherapy with
vincristine, dactinomycin and cyclophophamide (VAC) are used preoperatively.
Adjuvant chemotherapy follows surgery and decreases recurrences.i The tumor
metastasizes to lungs and lymph nodes. Poor prognostic signs include increased
age, increased ESR and leukocytosis at presentation.
References
Eggli, KD et al., Ewing's Sarcoma, Radiologic Clinics of North America,
31(2):325-337, March, 1994.
Bulloughs, Peter, Orthopaedic Pathologv (third edition), Times Mirror
International Publishers Limited, London, 1997.
Fletcher, Christopher, Diagnostic Histopathology of Tumors, Churchill
Livingstone:New York, 1990.
Huvos, Andrew, Bone Tumors:Diagnosis Treatment and Prognosis, W.B.Saunders, Co.,
1991.
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Solid Tumor: Ewing Sarcoma Family Tumors
Alternative Names:
Ewing's sarcoma, pPNET, Askin tumor
Definition
Ewing sarcoma family tumors are small, round cell tumors that arise
either in bone or soft tissues (extraosseous). These tumors are often
referred to as "Ewing sarcoma's" or "pPNET"
(peripheral primitive neuroectodermal tumor). In the past, chest
wall pPNET’s were called Askin tumor. The cell of origin of this
family of tumors is unknown. Ewing sarcoma family tumors can occur
at any site, but most commonly develop in the arms or legs, pelvis or
chest wall. These tumors can spread to the lungs, bone and bone
marrow. Pain and swelling at the sites of disease are the most
common presenting symptoms. Sometimes patients may also have fever.
Because these symptoms are suggestive of an infection, a delay in the
diagnosis of a malignancy may occur.
More than 85 percent of Ewing sarcoma family tumors are
characterized by a specific translocation between chromosomes 11 and 22. This
translocation puts together pieces of two chromosomes (genetic material)
that would normally not be together, and fuses two genes, FLI and
EWS, creating what is called a fusion transcript. This translocation is
felt to be important in why these tumors develop. In addition, the
detection of this translocation in tumor samples has improved our
ability to accurately diagnose these tumors.
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Incidence
Ewing sarcoma family tumors are the second most common type of bone
cancer in children and adolescence. There are approximately 200 new
cases of this type of tumor diagnosed in the United States per year.
Almost 50 percent of patients with Ewing family of tumors are between 10
and 20 years of age.
Influencing Factors
These tumors are very uncommon in people of African American and Asian
descent.
Ewing sarcoma family of tumors are not commonly associated with other
congenital diseases and there is no convincing evidence that this type
of tumor is inherited. Although a rare occurrence, Ewing sarcoma
family of tumors can occur as a second malignancy, especially in
patients who have received radiotherapy.
Survival Rates
About two-thirds of children with localized disease become long-term
survivors. Within this group of patients, patients with tumors that are
not easily accessible to surgery, such as primary tumors in the pelvis,
have a poorer outcome. Younger patients and those with smaller
tumors tend to do better although these factors seem to be less
important when more intensive chemotherapy is used.
If the disease has spread to other parts of the body, survival rates
are less than 30 percent.
Treatment Strategies
From past experience, it is clear that most patients who are treated
with local therapy alone (surgery and/or radiation therapy), will have
tumor recurrence, usually at a distant site. For this reason,
chemotherapy has become part of the standard treatment for Ewing family
of tumors. Chemotherapy kills tumor cells at the site of primary
disease as well as tumor cells in other areas of the body that cannot be
seen. Vincristine, cyclophosphamide, doxorubicin, etoposide and
ifosfamide are the most commonly used chemotherapeutic agents. Certain
patients may also benefit from blood stem cell transplantation or an
autologous bone marrow transplant. Autologous transplants use the
patient's own marrow.
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BRTS
