Soft Tissue Tumors Flashcards
What is the basic definition of a soft tissue tumor
Mesenchymal proliferations that occur in the extraskeletal, nonepithelialized tissues of the body, excluding the viscera, coverings of the brain, and the lymphoreticular system.
What do we call a connective tissue neoplasm
A sarcoma.
Lipoma
Basically a benign adipose tumor
Are Lipomas usually slow growing or fast growing?
Usually slow growing
What is the ifference between a Lipoma and Liposarcoma?
THE HISTOLOGY. Histology is important in soft tissue tumors.
In a liposarcoma you will generally see atypical cells. For example, a lipoblast may be present. Basically a lipoblast is a weird cell with an atypical nucleus and lipid vesicles in the cytoplasm.
What is a nodular fascitis?
Rapidly growing, small benign , fibrous proliferationon the subcutis.
Nodular fascitis is most common in what age group?
Young adults
Nodular fascitis characteristically presents with what type of growth pattern?
Rapid
Nodular fascitis generally follows what?
Injury. It is thought to be a mesenchymal reaction to injury
Nodular fascitis most commonly seen in what areas of the body?
Arms. Particularly the flexxor surfaces of the arms
What does the histology look like in nodular fascitis?
Said to have a “loose tissue culture appearance”
What is Myositis Ossificans?
Reactive bone formation in the muscle as a result of injury. Entirely benign.
Mysositis Ossificans generally occurs in what area of the body>?
Lower limb
What is the key feature in differentiating myositis ossificans from a malignancy
Myositis ossificans shows a maturation pattern. The maturation pattern is woven bone at the periphery, but immature bone at the center. Malignancy does not show this pattern.
What are the two classifications of fibromatoses?
Superficial and deep.
Superficial fibromatoses appear where?
Hands, feet, penis
Which of the superficial fibromatoses is most common
The palmar one
Does fibromatoses tend to affect one sex more than the other?
Yes. Male predominance
Palmar fibromatoses generally appear on one side only?
FALSE. Generally bilateral
Plantar fibromatoses
Generally appear in a younger age group but are also bilateral in most cases
Penile fibromatoses
Rare. Generally accompany other superficial fibromatoses
What is infantile digital fibromatoses
superficial fibromatoses that appear in the digits of young children and are characterized by inclusion like condensations of cytoplasmic actin.
What is Dupuytrens’s contracture
It is a condition of fixed flexion of the hand where the fingers bend towards the palm and cannot extend.
What fingers are most commonly affected?
Ring and pinky
Deep Fibromatoses
Aggressive, Rare, More common in females until after their 20’s.
Deep fibromatoses generally occur where in peds and in whom?
Extra-abdominal, females
Deep fibromatoses generally appear where pts in their late 20’s and who is generally affected?
Abdominal wall, females typically affected still. Past this, however, no sex predisposition and tumors do not occur in the abdomen as often.
Does radiation work on these tumors?
Nope. They are not malignant….do not divide quickly.
Definition of a fibrosarcoma
Tumor of mesenchymal origin that is composed of MALIGNANT FIBROBLASTS in a collagen background.q
Where may fibrosarcomas develop?
THey may be soft tissue masses or bone tumors.
Generally develop in the lower extremities (femur and Tibia if in bone, thigh and posterior knee if in soft tissue)
When a fibrosarcoma arises in bone, what part of the bone is it in?
METAPHYSIS OF LONG BONES OR THE PELVIS
Most frequently diagnosed in pts in what decade of life?
4th
What is the prognosis of fibrosarcoma
Poor in adults. There is an infantile form that has a great prognosis however.
Histology of a fibrosarcoma?
Herringbone pattern. Nuclei are spindle shaped with pointed ends
What the hell is a dermatofibroma
Can also be called a fibrous histiocytoma. It basically is a benign growth of dermal dendritic histiocytic cells.
Dermatofibroma may arise after….
relatively minor trauma like an insect bite or thorn prick
DF Generally look like what
firm nodules, small
DFSP
Dermatofibrosarcoma protuberans
DFSP common or uncommon
Uncommon, Locally aggressive though with a high recurrence rate, It is a cutaneous malignancy that arises from the dermis and invades deeper subcutaneous tissue.
DFSP exhibits partial features of three cell types, they are?
fibroblastic, histiocytic, neuroectodermal.
malignant fibrohistiocytoma
MOst common soft-tissue sarcoma
Most important prognostic factor for malignant fibrohistiocytoma?
Clinical stage ( tumor grade, size, presence of metastases)
Distant metastasis of malignant fibrohistiocytoma seems to go where?
lung, bone, liver
Histiologic appearance of malignant fibrohistiocytoma?
Storiform, woven mat appearance
Rhabdomyosarcoma definition
tumor made up of cancerous muscle cells,
Two thirds of rhabdomyosarcomas are found in what age group
children under ten
Most common sites of Rhabdomyosarcoma development>
Adjacent to the skull, Around the eye, Nose and throat, arms and legs, urinary system and reproductive organs
Prototypical cell type in rhabdomyosarcoma
Strap cell. ELongated bizzarre looking cells
Leiomyoma definition
Tumor of the smooth muscle. Usually the wall of the uterus
Leiomyomas affect what percentage of reproductive age women?
25-40%
Most Leiomyomas
regress after menopause, are asymptomatic, may be found anywhere in the body on smooth muscle
Typical cell appearance in a Leiomyoma
Cigar shaped
Leiomyosarcoma are most common where
uterus, abdomen, or pelvis
If you see cigar shaped cells indicative of a Leiomyosarcoma but also see mitotic figures
This is bad.
Sarcomas tend to metastasize where and why?
Lungs, because they typically spread hematogenously.
