Soft Tissue Tumors Flashcards
What are soft tissue tumors?
mesenchymal proliferations that occur in the extraskeletal, nonepithelialized tissues of the body, excluding the viscera, coverings of the brain, and the lymphoreticular system
What is sarcoma?
a connective tissue neoplasm, usually highly malignant, formed by proliferation of mesodermal cells
What is a Lipoma?
benign, circumscribed, lobular, non-encapsulated mass, most are small and may grow for a long time
What is a liposarcoma?
a malignant fat tissue tumor
- grossly looks like lipoma; but microscopically - cellular with atypical cells – lipoblasts are present
* lipoblasts have bizarre nucleus w/ vesicles of lipid in cytoplasm
What is nodular fascitis?
- a reactive proliferation
- small benign fibrous proliferation on subcutis
- young adults, rapid growth
- found on arms! - flexor aspects of forearm
What is Myositis ossificans?
- reacitve proliferation
- as a result of injury, entirely benign
- often lower limb after blunt trauma
- Woven bone is well-formed at the periphery but immature bone is at the center
- the previous maturation in number 4 is not going to be present in malignancy- useful for distinguishing!
What is fibromatosis superficial?
- small lesion of hand - plantar is most common, bilateral, young male
- lesion of penis - Peyronie dz - in association w/ other superficial
- lesion of feet - in kids, also bilateral
What is Duptyren’s Contracture?
- fixed flexion contracture of the hand where the fingers bend towards the palm and cannot be fully extended
- palmar aponeurosis becomes hyperplastic and undergoes contracture
- progresses slowly, painless
- tissue under skin thickens and shortens on palm
What is deep fibromatosis?
- Tumors are large, and local control can prove difficult
- bland, spindle cell proliferation with no mitotic figures and no necrosis, despite the very large size of the tumor
What is a fibrosarcoma?
- a tumor of mesenchymal cell origin that is composed of malignant fibroblasts in a collagen background
- painful
- metaphysis of long bone and pelvis
- men, lower extremities
5 Dxed in 4th decade commonly. if in kids – good prognosis!
- . It can occur as a soft-tissue mass or as a bone tumor
What is the difference of fibromas related to soft tissue and those of bone tumors?
Soft Tissue
- the thigh and the posterior knee
- large, painless mass deep to fascia and has an ill-defined margin
What is this pattern called and what cancer is it found it in?
fibrosarcomas are said to demonstrate a “herringbone” patter
What is a dermatofibroma?
- a fibrohistiocytic tumor
- growth of dermal dendritic histiocytic cells
- found in legs and arms
- firm nodules – yellow to brown
- dimpling : tethering of the skin to the underlying fibrous tissue.
What is a deramtofibrosarcoma protuberans?
- relatively uncommon soft tissue neoplasm with intermediate- to low-grade malignancy
- high recurrence rate
- cutaneous malignancy that arises from the dermis and invades deeper subcutaneous tissue
- gross path: umbilicated, somewhat irregular neoplasm (not dimpled!)
What is Malignant Fibrous Histiocytoma?
- spindled and rounded cells exhibiting a storiform
- MFH accounts for 20-24% of soft-tissue sarcomas – most common soft tissue sarcoma of adult
- common site of mets is lungs, rarely to bone and liver
Describe what is happening here!
the transition from benign to malignan
Left: Dermatofibroma : bland histiocytic type cells interdigitate between normal collagen bundles.
Middle: dermatofibrosarcoma protuberans : greater cellularity, greater cellular atypia
Right :malignant fibrous histiocytoma (storiform)
What is rhabdomyosarcoma?
- tumor made up of cancerous muscle cells called rhabdomyoblasts
- fish flesh appearance
- common sites: Adjacent to the base of the skull (parameningeal); around the eye (orbital); other sites in the head and nec
What cancer is this?
Rhabdo – usually made up of bizarre cells
What is a leiomyoma?
- benign smooth muscle – can be ubquitious since SM is found everywhere
- uterus is a common site
- reach quite a large size; in doing so they outgrow their blood supply and may undergo areas of necrosis with ultimate formation of one or more cysts (arrow).
key points about uterine leiomyomas
Etiology unknown
Cells are clonal and are estrogen sensitive
Affect 25-40% of reproductive age women
Tend to regress after menopause
Most are asymptomatic
May be solitary or multiple
May be submucosal, intramural, or subserosal with pedunculation (on a stalk)
What types of cells are seen in leiomyomas and leiomyosarcoma?
cigar shaped: has spindle shaped nuclei with blunt ends
What are leiomyosarcoma?
- malignant cancer of smooth muscle.
- more common in the uterus, abdomen, or pelvis
What is the difference btw the two pics?
Both are leiomyosarcoma.
Left: show two mitotic figures within one field, a very worrisome observation = low grade
Right: more bizarre cells are almost unrecognizable as having a smooth muscle origin = high grade
Where do sarcomas like to go to?
lungs b/c tend to spread through the bloodstream (hematogenous spread) rather than through the lymphatic system
* Pulmonary metastases are a major cause of mortality for all sarcoma patients
