Pedi Other Sarcomas Flashcards
What tumor type is composed of a mixed group
of mesenchymal malignancies that are generally
defined as either soft tissue (80%) or bony/
cartilaginous (20%) tissue?
Sarcomas. These tumors can arise from muscle, nerve, fat,
vessel, fibrous tissue, bone, or cartilage.
What is the most common initial manifestation
of head and neck sarcoma?
Painless mass. Symptoms generally are related to the
structures involved and uncommonly include pain. Referred
otalgia may be seen in patients with oropharyngeal or
hypopharyngeal lesions. Pain can also represent bony
impingement of nervous structures.
How are sarcomas defined in general terms?
Tissue of origin
Histologic grade
Anatomical subsite in the head and neck
List examples of high-grade and low-grade
sarcomas of the head and neck.
High grade ● Osteosarcoma* ● Malignant fibrous histiocytoma* ● Rhabdomyosarcoma* ● Angiosarcoma* ● Synovial sarcoma ● Alveolar soft part sarcoma ● Ewing sarcoma Low grade ● Dermatofibrosarcoma protuberans ● Desmoid tumors ● Atypical lipomatous tumors ● Require individual grading ● Chondrosarcoma ● Fibrosarcoma ● Neurogenic sarcoma ● Hemangiopericytoma *Most common in the head and neck (50%)
How does the anatomical subsite within the head
and neck influence decision-making in the
management of sarcomas?
The ability to resect the tumor fully, without causing undue
morbidity, significantly influences surgical versus nonsur-
gical decision-making.
In the pediatric population, what percentage of
sarcomas manifest in the head and neck?
Around 35% of sarcomas in children manifest in the head
and neck; this rate is greater than that in adults.
What historical factors increase the risk of
developing a sarcoma?
History of radiation of the head and neck Li-Fraumeni syndrome (p53 mutation) Hereditary retinoblastoma (Rb-1 mutation) Neurofibromatosis type 1 (NF-1) Gardner syndrome Nevoid basal cell carcinoma syndrome Carney triad Hereditary hemochromatosis Werner syndrome
How might a sarcoma differ from a squamous cell
carcinoma of the same anatomical subsite during
examination of the upper aerodigestive tract?
Sarcomas will appear as a submucosal mass.
What radiographic workup is necessary for
pediatric head and neck sarcomas?
CT scan: Soft tissue extent, nodal involvement, cortical
bony involvement
MRI scan: Soft tissue, bone marrow, perineural extension,
orbital and intracranial involvement
Fludeoxyglucose (FDG)-PET/CT scan: Staging, response to
therapy, surveillance
What is the most likely site of metastasis from
head and neck sarcomas, and how does this
influence diagnostic workup?
Lung. Imaging of the chest is required: chest-X-ray for low-
grade lesions, CT for high-grade lesions.
During initial diagnosis of a soft tissue mass in the
head and neck, why might core needle biopsy or
excisional biopsy be preferred to FNA?
FNA may not provide enough tissue for extensive immu-
nohistochemical analysis, and it has a higher risk of being
nondiagnostic. However, FNA is minimally invasive, can be performed without conscious sedation in some children,
and has a reported sensitivity of 95%.
What mesenchymal vascular sarcoma arises from
the pericytes of Zimmerman?
Hemangiopericytoma
Notably, 10 to 25% of all hemangiopericytomas
are in the head and neck. What is the most
common subsite?
Sinonasal tract
True or False. All hemangiopericytomas diagnosed
in the pediatric population are acquired after birth.
False. 5% of all hemangiopericytomas are congenital and are
considered benign.
How do pediatric hemangiopericytomas most
commonly present?
Most are slow-growing, soft, subcutaneous, painless
masses. Compared with adult-onset hemangiopericytomas,
the pediatric variant generally follows a more benign clinical
course.
How are pediatric hemangiopericytomas
managed?
Surgical resection to negative margins is the mainstay of
treatment for malignant lesions.
Radiation and chemotherapy may improve local and distant
control, although distant metastases are less common in
the head and neck.
Chemotherapy has been used for congenital lesions.
What aggressive malignant sarcoma arises most
commonly in the axial long bones of the lower
extremities and pelvis but can arise in extraosseous
soft tissue sites, such as the sinonasal tract and
paranasal sinuses, orbit, scalp, and paravertebral
areas of the neck?
Ewing sarcoma
What is the tissue of origin for Ewing sarcoma?
This topic is controversial; possible origins include totipo-
tential mesenchymal cells and primitive neuroectodermal tumors.
What are the most common initial symptoms
associated with Ewing sarcoma?
Pain and regional swelling
What proportion of patients with Ewing sarcoma
manifest with metastatic disease?
Ewing sarcoma is considered metastatic at presentation in
nearly all patients.
How is Ewing sarcoma managed?
Treatment comprises surgical excision with concurrent
chemotherapy (vincristine, actinomycin-D, cyclophospha-
mide) and radiation therapy.
What tumor is a type of spindle cell sarcoma
that is either associated with peripheral nerves or
shows nerve sheath differentiation?
Malignant peripheral nerve sheath sarcoma is a malignant,
aggressive tumor with a high rate of metastases.
Malignant peripheral nerve sheath tumors are
masses that can be associated with pain and
dysesthesia. How often is a nerve of origin
identified?
~ 70%
What hereditary condition is a significant risk
factor for the development of malignant
peripheral nerve sheath tumors?
NF-1. Up to 40% of tumors develop in a preexisting
neurofibroma.
What important prognostic factors predict poor
outcome in patients with malignant peripheral
nerve sheath tumors?
Tumor size > 5 cm, tumor invasiveness (T2), concomitant
NF-1, head and neck location
What is the management strategy for malignant
primary nerve sheath tumors?
Surgical resection is the mainstay of treatment and a strong
predictor of survival. Adjuvant chemotherapy or radiation
therapy potentially has a role.
Alveolar soft part sarcoma arises from which tissue type(s)?
Myogenic and neural cells (controversial)
Although they are extremely rare, two-thirds of
head and neck alveolar soft part sarcomas arise in
which anatomical subsites and manifest with what
common symptom(s)?
They manifest in the orbit and tongue as a painless mass.
What demographic is most commonly affected
by alveolar soft part sarcomas?
Females aged 10 to 30 years
How are alveolar soft part sarcomas treated?
Surgical resection with adjuvant radiation therapy or
chemotherapy (in phase I or phase II trials)
What are the two most common locations for
osteosarcoma within the head and neck?
Mandible and maxilla
What are the most common initial symptoms
associated with osteosarcoma of the head and
neck?
2 to 6 months of a painless mass, dental pain, or loose teeth
What is the mainstay of therapy for osteosarcoma
of the head and neck?
Aggressive surgical resection. Postoperative radiation ther-
apy is controversial. The addition of chemotherapy to
surgery has been shown to be beneficial.
Despite advances in treatment, surgical resection,
and reconstruction, survival for patients with
osteosarcoma is poor. What prognostic factors
have been identified?
Surgical margins (i.e., positive margins are associated with poor outcome), recurrence, primary tumor arising in
previously radiated bone, and tumors arising in extra- gnathic bone (i.e., less likely to achieve wide resection). No
differences have been identified between pediatric and
adult populations.
