Malignant Mesenchymal Neoplasms

Question 1

What oral path lesion is described below?

“malignancy of fibroblastic differentiation”

Answer 1

fibrosarcoma

Question 2

How common is fibrosarcoma? What age group is most affected?

Answer 2

• once among the most common soft tissue sarcomas, but not less frequent due to improved subclassification
• adults

Question 3

Describe the clinical appearance of fibrosarcoma. Histology?

Answer 3

• may present as a soft tissue mass or as an intrabony lesion
• note: histology has a “herring bone” pattern; highly cellular proliferation, lots of mitotic figures

Question 4

What is the recommended treatment for fibrosarcoma?

Answer 4

• wide to radical surgical excision; little response to radiation/chemotherapy, similar to many soft tissue sarcomas

Question 5

What is the prognosis of fibrosarcoma? Recurrence? 5-year survival? Metastasis?

Answer 5

• 50% recurrence
• 40-70% 5-year survival
• metastasizes to lung, bone, liver

Question 6

What oral path lesion is also known as neurogenic sarcoma?

Answer 6

malignant peripheral nerve sheath tumor

note: malignancy of schwann cell differentiation

Question 7

What are the 2 causes of malignant peripheral nerve sheath tumor? What age groups are affected by each?

Answer 7

• spontaneously (around 5th decade)

- associated with neurofibromatosis, type 1 (around 4th decade)

Question 8

Describe the histology of malignant peripheral nerve sheath tumors.

Answer 8

• invasive cellular proliferation of spindle-shaped cells with wavy nuclei
• similar appearance with routine hematoxylin and eosin-stained sections to several other tumors
• usually shows S100+ by IHC (S100 proteins are marker for neural tissue)

Question 9

What is the recommended treatment for malignant peripheral nerve sheath tumors?

Answer 9

• radical surgical excision +/- chemotherapy or radiation therapy
• overall 50% 5-year survival and 35% 10-year survival

Question 10

What oral path lesion was first described as a disease in elderly white males of Mediterranean descent?

Answer 10

kaposi sarcoma

Question 11

What oral path lesion is a malignancy of the blood vessels? This is caused by infection of ___.

Answer 11

• karposi sarcoma

- HHV-8

Question 12

What are the 4 types of karposi sarcoma?

Answer 12

• classic
• endemic (african)
• iatrogenic (transplant associated)
• epidemic (AIDS-related)

Question 13

Where does classic karposi sarcoma usually present? What does it look like clinically?

Answer 13

• lower extremities of older adult males; oral involvement uncommon
• initially purple cutaneous macules that gradually develop into plaques and tumors

Question 14

What age range is most at risk for endemic (African) karposi sarcoma? What sites can it become involved in?

Answer 14

• affects wide age range of patients, including children
• widely varied course, from indolent to aggressive
• lymph nodes and viscera involved in lymphadenopathic form (poor prognosis!)

Question 15

What sites are affected with iatrogenic (transplant-associated) karposi sarcoma? How can it be treated?

Answer 15

• usually affects the skin of a small percentage (

Question 16

What category of patients are most affected by epidemic (AIDS-related) karposi sarcoma? How common is it? What is the most common site?

Answer 16

• predominantly in gay or bisexual men; rarely in women

- frequency has declined from 25% to

Question 17

What is the recommended treatment for karposi sarcoma?

Answer 17

• excision for small cosmetically unacceptable lesions
• radiation therapy for skin lesions
• systemic chemotherapy or intralesional injections with anti-cancer agents (vinblastine)

Question 18

What is the prognosis for each type of karposi sarcoma?

Answer 18

• CLASSIC: fair (patients usually die of something else)
• ENDEMIC: variable (lymphadenopathic form has poor prognosis)
• IATROGENIC: fair to poor (lesions may regress with reduction in immunosuppressive therapy)
• AIDS-RELATED: fair

Question 19

What oral path lesion is described below?

“relatively uncommon malignancy of skeletal muscle”

Answer 19

rhabdomyosarcoma

Question 20

What age group is most affected by rhabdomyosarcoma? What sites?

Answer 20

• children and adolescents (50% of childhood soft tissue sarcomas)
• head and neck involvement is common (35%)

Question 21

What is the clinical appearance of rhabdomyosarcoma?

Answer 21

• infiltrative rapidly growing mass
• when rhabdomyosarcoma grows into body cavity (like oral cavity), lesion may appear similar to a bunch of grapes (called “sarcoma botyoides”)

Question 22

Describe the histology of rhabdomyosarcoma.

Answer 22

• rounded spindle cells with a large nuclei
• may have strap cells (skeletal muscle differentiation)
• immunohistochemistry will show skeletal muscle (desmin stain)

Question 23

What is the recommended treatment of rhabdomyosarcoma? Prognosis?

Answer 23

• wide surgical excision combined with radiation therapy and multi-agent chemotherapy
• prognosis depends on stage and subtype; 5-year survival ranges 44-72%