Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account

Genetic syndromes

A minority in soft tissue tumors

Li-Fraumeni syndrome

Soft tissue SARCOMA; defective p53 gene. These patients are prone to different malignancies

Neurofibromatosis type I

Maligant peripheral nerve sheath tumor, neurofibromas

Osler-Weber Rendu

Telangiectasia (superficial - skin, mucus membranes) and arteriovenus malformations (organs). Arterioles directly connect to venules.

Gardner syndrome

Fibromatosis/ desmoids tumors. Multiple colonic polyps, associated with colonic adenmoas

Tumors of adipose tissue



Benign, most common soft tissue tumor (STT) characteristic cytogenetic abnormalities in the subcutaneous tissue of the prox. Extremities and trunk. Well encapsulated and consists of mature adipose tissue; Painless,soft, and mobile and cured by excision

Lipoma subtypes


Conventional lipoma

Discussed above; abnormal chromosomal rearrangements





Spindle cell lipoma

Abnormal chromosomal rearrangements



Pleomorphic lipoma



Malignant tumor of adipose tissue. MOST common Sarcoma of adulthood located deep in the soft tissue, Prox. Extremities and retroperoneum. Masses are LARGE and bulky. 3 grades: well differentiated Grade I; Mixoid - Grade II; Pleomorphic - Grade III. May recur after excision

Tumor like conditions of adipose tissue


Fat necrosis

Can occur in the pancreas. In other areas it is painless palpable mass. Skin thickening or retraction; mammographic density or calcification (common in breasts); prior history of trauma. Major clinical significance is confusion with malignancy

Fine needle aspiration

Use it to withdraw some biopsy material; ethanol fixed slide, air dried slide;

Fibrous tumors

Non neoplastic, secondary to trauma(physical, ischemic), grow rapidly. Histo: hypercellular with plump fibroblast and mitosis. Proliferative lesions that can be confused with cancer.

Fibrous Tumor-like conditions

Non neoplastic, secondary to trauma(physical, ischemic), grow rapidly. Histo: hypercellular with plump fibroblast and mitosis. Proliferative lesions that can be confused with cancer.

Pseudosarcomatous proliferation


Nodular fasciitis/ pseudosarcomatous fasciitis

Most common reactive pseudosarcoma in adults; chest, arms, back; history is several weeks. Solitary, rapidly growing, painful mass that preceding truma. It has a decent capsule and zonation, the central zone is eosinophilic and the peripheral zone is cellular. Looks malignant like spindle cell carcinoma (DDx); Histo: located deep in dermis, subcutis, muscle, poorly defined borders. Immature fibroblasts/myofibroblasts. Pleomorphic, conspicuous nuclei, abundant mitotic figures with extravasated blood and lymphocytes

Myositis ossificans

Adolescents. Reactive fibroblastic proliferation with calcifying mass in soft tissue or metaplastic bone tissue. Common in muscles of proximal extremities. It is a 3-6 cm well demarcated lesion with history of previous trauma (>50).

Looks like extraskeletal osteosarcoma (DDx)



Tumor like conditions/ proliferation of fibroblasts



Dupuytren contracture

Thickening of palmar skin due to proliferation of fibroblasts between picky and ring finger, slow progression. Has functional problems extending fingers and often bilateral

Plantar fibromatosis

Doesn't cause much functional problems because fibroblast thickening on sole of foot and often unilateral

Peyronie disease

Fibrous penile disease leading to deformities and preventing intercourse, usually thickened on the dorsum

Deep seated


Desmoid tumors

M=F of any age but often in found in TEENs. Well differentiated fibroblasts; they don't metastasize; these are low grade malignant tumors and can encase the abdominal organs and cause fibrosis and constriction. Can be disfiguring, disabling, painful and responds to chemo like malignant tumors do. This thing is proliferative, benign, and malignant! Adequate excision is usually curative; recur locally if incompletely excised.

3 types



Extra abdominal - shoulder, chest wall, back thigh MALES = FEMALES


Abdominal - musculo-aponeurotic structures of abdominal wall found in women after pregnancy


Intra-abdominal - mesenteric or pelvic wall and is associated with Gardner's syndrome (familial adenomatous polyposis)

Anything benign cannot

Metastasize (obviously)

Malignant tumors of fibrous tissue



Malignant tumors of fibroblasts. SEE BONE section for more INFO. It is unencapsulated/ hypercelluar with a Herringbone pattern. Infiltrative + pleomorphic . Aggressive, metastatic, and often reoccur. If it's very malignant and high grade, you don't see a good herring bone so you have to do immunohistochemistry. IN this case there is usually hemorrhage, necrosis, and mitosis.

Fibrohistocytic tumors

Descriptive term for cells that look like fibroblast and macrophages (histocytes). They are in reality, fibroblastic in origin.

Benign fibrous histiocytoma/ dermatofibroma

Middle aged FEMALES' legs are affected. Painless, slow growing (<1cm), and can be pigmented. Confused with seborrhic keratosis or melanoma. DOWNWARD dimpling upon compression lateral compression. Benign spindle cells with overlying epithelial hyperplasia

Malignant fibrous histiocytoma

Renamed to Fibrosarcoma b/c this description is an oxymoronic paradox (paradoxical oxymoron?) it's just a contradiction

Tumors of skeletal muscles


Benign rhabdomyoma

Found in cardiac cells associated with tuberous sclerosis

Malignant rhabdomyosarcoma

<20 people. Most common Soft tissue tumor of childhood. Found in head, neck, and genitourinary tract. Diagnostic is tadpole cell or strap cell; Immunohistochemistry: DESMIN, myogen, MYOD1 markers

Pleomorphic rhabdomyosarcoma

RARE, grade III, and located deep in soft tissues. They are numerous, large, bizarre, and multinucleated.

Alveolar rhabdomyosarcoma

EARLY adolescents. Grade II. 20% of rhabdomyosarcoma found in, deep muscles of the extremities. Fibrous septae resembling alveoli

Embryonal rhabdomyosarcoma

CHILDREN < 10Grade I, 60% of rhyabdomyosarcomas. Found in head or genital region

Sarcoma botryoides

Part of embryonal rhabdomyosarcoma that resembles bunches of grapes.

Tumors of smooth muscles


Benign leiomyomas


Malignant leiomyosarcoma

20% of tissue sarcomas. Found in the deep soft tissues of the extremities or retropreitoneum. NOT COMMON in Uterus. Pain, firm, bulky mass with malignant smooth muscle spindle cells; IHC: Smooth muscle Actin (SMA); DESMIN

Glomus Tumor/ glomangioma

Benign painful tumors of the distal digits underneath the fingernails. Derived from MODIFIED smooth muscle cells

Other tumors


Synovial Sarcoma

Soft tissue tumor growing around the joint, knee, or thigh. Only 10% grows IN the join. It's BIPHASIC - epithelial and mesenchymal tissue present with radiographic calcification



Cytogenetically: t(x;18)(p11;q11)


Metastatic to lung, bone, lymph nodes


Chemo and surgery is treatment


Pyogenic granuloma

Does not live up to its name. Capillary hemangioma that is rapidly growing with pedunculated red nodules seen on skin, gingival, or oral mucosa. My ulcerate and bleed. Pregnancy tumor

Painful soft tissue tumors








Eccrine poroma






Fine Needle aspiration

Diagnosis depends on the tissue you picked up so try to get as much as possible

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording