Pedi Other Sarcomas

Question 1

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?

Answer 1

Sarcomas. These tumors can arise from muscle, nerve, fat,

vessel, fibrous tissue, bone, or cartilage.

Question 2

What is the most common initial manifestation

of head and neck sarcoma?

Answer 2

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.

Question 3

How are sarcomas defined in general terms?

Answer 3

Tissue of origin
Histologic grade
Anatomical subsite in the head and neck

Question 4

List examples of high-grade and low-grade

sarcomas of the head and neck.

Answer 4

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%)

Question 5

How does the anatomical subsite within the head
and neck influence decision-making in the
management of sarcomas?

Answer 5

The ability to resect the tumor fully, without causing undue

morbidity, significantly influences surgical versus nonsur-
gical decision-making.

Question 6

In the pediatric population, what percentage of

sarcomas manifest in the head and neck?

Answer 6

Around 35% of sarcomas in children manifest in the head

and neck; this rate is greater than that in adults.

Question 7

What historical factors increase the risk of

developing a sarcoma?

Answer 7

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

Question 8

How might a sarcoma differ from a squamous cell
carcinoma of the same anatomical subsite during
examination of the upper aerodigestive tract?

Answer 8

Sarcomas will appear as a submucosal mass.

Question 9

What radiographic workup is necessary for

pediatric head and neck sarcomas?

Answer 9

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

Question 10

What is the most likely site of metastasis from
head and neck sarcomas, and how does this
influence diagnostic workup?

Answer 10

Lung. Imaging of the chest is required: chest-X-ray for low-

grade lesions, CT for high-grade lesions.

Question 11

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?

Answer 11

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%.

Question 12

What mesenchymal vascular sarcoma arises from

the pericytes of Zimmerman?

Answer 12

Hemangiopericytoma

Question 13

Notably, 10 to 25% of all hemangiopericytomas
are in the head and neck. What is the most
common subsite?

Answer 13

Sinonasal tract

Question 14

True or False. All hemangiopericytomas diagnosed

in the pediatric population are acquired after birth.

Answer 14

False. 5% of all hemangiopericytomas are congenital and are

considered benign.

Question 15

How do pediatric hemangiopericytomas most

commonly present?

Answer 15

Most are slow-growing, soft, subcutaneous, painless
masses. Compared with adult-onset hemangiopericytomas,
the pediatric variant generally follows a more benign clinical
course.

Question 16

How are pediatric hemangiopericytomas

managed?

Answer 16

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.

Question 17

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?

Answer 17

Ewing sarcoma

Question 18

What is the tissue of origin for Ewing sarcoma?

Answer 18

This topic is controversial; possible origins include totipo-
tential mesenchymal cells and primitive neuroectodermal tumors.

Question 19

What are the most common initial symptoms

associated with Ewing sarcoma?

Answer 19

Pain and regional swelling

Question 20

What proportion of patients with Ewing sarcoma

manifest with metastatic disease?

Answer 20

Ewing sarcoma is considered metastatic at presentation in

nearly all patients.

Question 21

How is Ewing sarcoma managed?

Answer 21

Treatment comprises surgical excision with concurrent

chemotherapy (vincristine, actinomycin-D, cyclophospha-
mide) and radiation therapy.

Question 22

What tumor is a type of spindle cell sarcoma
that is either associated with peripheral nerves or
shows nerve sheath differentiation?

Answer 22

Malignant peripheral nerve sheath sarcoma is a malignant,

aggressive tumor with a high rate of metastases.

Question 23

Malignant peripheral nerve sheath tumors are
masses that can be associated with pain and
dysesthesia. How often is a nerve of origin
identified?

Answer 23

~ 70%

Question 24

What hereditary condition is a significant risk
factor for the development of malignant
peripheral nerve sheath tumors?

Answer 24

NF-1. Up to 40% of tumors develop in a preexisting

neurofibroma.

Question 25

What important prognostic factors predict poor
outcome in patients with malignant peripheral
nerve sheath tumors?

Answer 25

Tumor size > 5 cm, tumor invasiveness (T2), concomitant

NF-1, head and neck location

Question 26

What is the management strategy for malignant

primary nerve sheath tumors?

Answer 26

Surgical resection is the mainstay of treatment and a strong
predictor of survival. Adjuvant chemotherapy or radiation
therapy potentially has a role.

Question 27

Alveolar soft part sarcoma arises from which
tissue type(s)?

Answer 27

Myogenic and neural cells (controversial)

Question 28

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)?

Answer 28

They manifest in the orbit and tongue as a painless mass.

Question 29

What demographic is most commonly affected

by alveolar soft part sarcomas?

Answer 29

Females aged 10 to 30 years

Question 30

How are alveolar soft part sarcomas treated?

Answer 30

Surgical resection with adjuvant radiation therapy or

chemotherapy (in phase I or phase II trials)

Question 31

What are the two most common locations for

osteosarcoma within the head and neck?

Answer 31

Mandible and maxilla

Question 32

What are the most common initial symptoms
associated with osteosarcoma of the head and
neck?

Answer 32

2 to 6 months of a painless mass, dental pain, or loose teeth

Question 33

What is the mainstay of therapy for osteosarcoma

of the head and neck?

Answer 33

Aggressive surgical resection. Postoperative radiation ther-
apy is controversial. The addition of chemotherapy to

surgery has been shown to be beneficial.

Question 34

Despite advances in treatment, surgical resection,
and reconstruction, survival for patients with
osteosarcoma is poor. What prognostic factors
have been identified?

Answer 34

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.