Otolaryngology--Head and Neck Surgery (eBook)

1

Second to accidents, what is the most common cause of death in children between 1 and 14 years of age?

Malignancy

2

What is the most common sarcoma of childhood?

Rhabdomyosarcoma. Up to 35% are found in the head and neck.

3

Which cell type gives rise to rhabdomyosarcoma, and what major histologic variants are described?

Primitive skeletal muscle cells (small, round blue cell tumor of childhood): embryonal, botryoid, alveolar, undifferentiated. Some include anaplastic. Embryonal and alveolar are the most common types, and embryonal type carries the best prognosis.

4

Where does pediatric head and neck rhabdomyosarcoma most commonly occur?

Parameningeal (50%): Paranasal sinuses, nasopharynx, nasal cavity, middle ear, mastoid, infratemporal fossa (5-year survival: 49%; considered high risk)

Orbit (25%) (5-year survival: 84%)

Nonorbital, nonparameningeal (25%): Scalp, parotid, oral cavity, pharynx, thyroid, parathyroid, neck (5-year survival: 70%)

5

What are the common initial symptoms associated with head and neck pediatric rhabdomyosarcoma?

Symptoms are due to progressive mass effect, local swelling, neurologic sequelae, or tissue necrosis. Bone marrow involvement can manifest as hematologic concerns.

6

What are the most important negative prognostic factors associated with pediatric rhabdomyosarcoma?

Diagnosis during infancy or adolescence; metastatic disease at diagnosis; alveolar histology; disease identified in a parameningeal location (risk for intracranial spread), in the extremities, or in the retroperitoneum or trunk; recurrence or progression during therapy

7

What diagnostic techniques are required to evaluate the primary tumor in rhabdomyosarcoma?

Biopsy: Open biopsy is done to ensure adequate tissue unless the lesion is small and difficult to access, in which case, needle biopsy may be acceptable.

Imaging: CT scan and magnetic resonance imaging (MRI) to evaluate extent of disease

8

What diagnostic techniques are required to evaluate locoregional and/or distant metastases in rhabdomyosarcoma?

Laboratory work (complete blood count [CBC], electrolytes, liver function, coagulation studies, renal function tests)

Technetium-99 bone scan

CT chest

Positron emission tomography (PET)/CT scan

Aspiration/biopsy of iliac bone marrow.

Distant metastases are more commonly found in the brain, lung, bone, and bone marrow.

9

Which group is credited with increasing the survival rate for patients with rhabdomyosarcoma from 30 to 70% since the 1970s?

The Intergroup Rhabdomyosarcoma Study Committee (now the Soft Tissue Sarcoma Committee of the Children's Oncology Group)

10

What is the clinical grouping or surgical pathologic staging system commonly used for staging rhabdomyosarcoma?

( Table 2.1)

Stage

Description

Group I

Localized disease, completely resected

A

Confined to organ or muscle of origin

B

Invasion outside organ/muscle of origin; regional nodes not involved

Group II

Compromised or regional resection including

A

Grossly resected tumors with microscopic residual tumor

B

Regional disease, completely resected, in which nodes may be involved and/or tumor extends into an adjacent organ

C

Regional disease with involved nodes, grossly resected, but with evidence of microscopic residual

Group III

Incomplete resection or biopsy with gross residual disease

Group IV

Distant metastases, present at onset

Data from Crist WM, Garnsey L, Beltangady MS, et al. Prognosis in children with rhabdomyosarcoma: a report of the intergroup rhabdomyosarcoma studies I and II (Intergroup Rhabdomyosarcoma Committee). J Clin Oncol. 1990 Mar;8 (3):443–52.

11

What is the tumor, node, and metastases (TNM) staging system for rhabdomyosarcoma introduced by the Intergroup Rhabdomyosarcoma Study IV?

( Table 2.2)

Stage

Description

T1

Confined to the anatomical site or origin

T2

Extension beyond site of origin

A: ≤ 5 cm in diameter

B: > 5 cm in diameter

N0

No clinically involved lymph nodes

N1

Clinically involved lymph nodes

NX

Clinical status unknown

M0

No distant metastasis

M1

Distant metastasis

MX

Distant metastasis unknown

Data from Neville HL, Andrassy RJ, Lobe TE, et al. Preoperative staging, prognostic factors, and outcome for extremity rhabdomyosarcoma: a preliminary report from the Intergroup Rhabdomyosarcoma Study IV (1991–1997). J Pediatr Surg. 2000 Feb;35(2):317–21.

12

Describe the staging system for rhabdomyosarcoma that combines the TNM and clinicopathologic groups to provide both prognostic and therapeutic recommendations.

Rhabdomyosarcoma prognostic stratification and standard treatment assignment (Prognosis, Event-Free Survival):

Excellent (> 85%)

Very good (75 to 85%)

Good (50 to 70%)

Poor (< 30%)

This system allows for risk-directed therapy.

13

Describe the favorable and unfavorable locations for head and neck rhabdomyosarcoma.

Favorable: Orbit and eyelid

Unfavorable: Parameningeal

14

True or False. In a patient with localized nonorbital, nonparameningeal head and neck embryonal rhabdomyosarcoma, if complete surgical excision can be achieved, radiation therapy may be avoided.

True. However, chemotherapy is recommended for all patients with rhabdomyosarcoma.

15

Is elective neck dissection for clinically negative necks recommended in patients with nonparameningeal rhabdomyosarcoma of the head and neck?

No

16

What are the most commonly used chemotherapeutic agents for treatment of rhabdomyosarcoma?

Vincristine, actinomycin D, cyclophosphamide

17

What are the most common late complications in patients treated for rhabdomyosarcoma of the head and neck?

Short stature, regional tissue hypoplasia, poor dentition, malformed teeth, impaired vision, decreased hearing, and learning disorders

18

What is the most common fibrous tumor of infancy?

Infantile myofibromatosis (solitary or multicentric; well-circumscribed, spindle-shaped cells, including fibroblasts and smooth muscle cells on histopathology)

19

What is the natural history of infantile myofibromatosis?

Most will involute by age 1 to 2 years. Visceral lesions causing functional impairment (e.g., pulmonary), may require surgical excision. For nonresectable, rapidly progressive, recurrent or symptomatic lesions, surgery, radiation therapy and chemotherapy should be considered.

20

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...