Soft Tissue Tumors Flashcards
What do soft tissue tumors arise from?
not mature cells, but pluripotent stem cells (soft tissue tumors are not that common)
Where are soft tissue tumors typically found?
up to 40% can be found on the thigh
What are the joint tumors?
ØGanglion cyst
ØGiant cell tumor of tendon sheath
ØTenosynovial Giant Cell Tumor
What is a ganglion cyst?
psuedocyte (because theres no true epithelial lining) arising from the joint capsule or tenden sheath and is considered a myxoid degeneration
What is this?
Ganglion cyst with the myxoid degeneration (light-blue)
treated by excision
What is a tenosynovial giant cell tumor?
collective name for a family of benign related tumors including localized neoplasms (aka giant cell tumor of tendon sheath) or diffuse (pigmented villa-nodular synovitis)
What is this?
a giant cell tumor of tendon sheath - multinucleated giant cells in a background of histiocytes and cells that resemble synoviocytes
this is the localized type of tenosynovial giant cell tumors
What dis?
This is the diffuse type of tenosynovial giant cell tumor previously called pigmented villanodular synovitis
Where does pigmented villanodular synovitis show up most commonly?
the knee and causes synovium proliferation
What are the tumors of adipose?
- lipomas
- liposarcomas
What dat?
lipoma- a benign tumor of fat (most common soft tissue tumor in adults) commonly found on the trunk in older men
How can you differentiate lipomas from angiolipomas?
most lipomas are mobile, slow growing, and PAINLESS (angiolipomas can have pain)
What this?
Lipoma- complete excision usually curative
remember: mobile, slow growing and PAINLESS
What is a common mutation assoicated with lipomas?
55-75% of solitary lipomas have rearrangements of HMGA2/HMGIC at 12q13-15
What is this? How to get rid of?
liposarcoma with the hallmark ‘lipoblast’ cell (lipid vacuoles that intent the central nucleus)
surgery is the mainstay
What is a liposarcoma?
common soft tissue tumor in late adulthood (50-60s) that RECUR LOCALLY AND REPEATEDLY UNLESS ADEQUATELY EXCISED
most common soft tissue sarcoma of adults
Where are liposarcomas commonly found?
DEEP soft tissue of the proximal extremities and in the retroperitoneum (bad!)
Immunostains for liposarcomas?
MDM2 and CDK4 for molecular testing for 12q13-15 amplification
What are the fibrous tumors?
- Nodular fasciitis
- Myositis Ossificans
- Fibromatosis (Superficial and Deep)
- Fibrosarcoma
What is nodular fasciitis?
a reactive pseudosarcoma consisting of plump fibroblasts that are solitary, RAPIDLY GROWING AND THERE IS A HX OF TRAUMA
What is the classic spot for nodular fasciitis?
the subdermal fat, commonly in the arms and antibrazos
What is Myositis ossificans?
a neoplasm distinguished by the presence of metaplastic bone that arises in the proximal extremities after TRAUMA, typically in **YOUNG ATHLETES**
looks like an osteosarcoma
What is superficial fibromatosis?
A benign, infiltrative fibroblastic proliferation that causes local deformity common in males
PALMAR surface neoplasm!!
What dis?
Deep fibromatosis
What are deep fibromatoses?
large infiltrative masses that occur but do not metastasize in females from teens-30s
Deep fibromatoses have an association with what?
APC gene or Beta-Catenin, both leading to increased WNT signaling
-Gardner’s Syndrome
Deep fibromatosis
two types: extra or intraabdominal
What are fibrosacromas?
malignant neoplasm of fibroblasts in adults
Where are fibrosarcomas commonly found?
deep in the thigh or retroperitoneum
Where do fibrosarcomas go to?
heme spread to the lungs most commonly (25%)
local recurrence is common
What dis?
Fibrosarcomas- patterns vary from resemblin fibromatosis to herringbone patterns to architectural disarray
How do fibrosarcomas appear grossly?
unencapsulated with necrosis and hemorrhage
What are the tumors of muscle?
- rhabdomyoma
- rhabdomyosarcoma
ID
rhabdomyoma with ‘spider’ cells
What is the most frequent primary tumor of the pediatric heart?
rhabdomyoma
may cause valvular or cardiac chamber obstruction
What is the progression of rhabdomyomas?
most spontaneously regress (more of a hamartoma than a true neoplasm)
50% of rhabdomyomas are associated with what?
tuberous sclerosis -mutations of TSC1 (hamartin) and TSC2 (tuberin)
ID
Rhabdomyosarcoma
these eosinophilic inclusions are the hallmark to histo diagnosis= rhabdomyoblasts! (these have sarcomeres and Z bands)
What is a rhabdomyosarcoma?
a MALIGNANT mesenchymal tumor with skeletal muscle differentiations
What are the subtypes of rhabdomyosarcomas?
- alveolar
- embryonal
- pleomorphic
What are the most common soft tissue sarcomas of childreen (under 20 yo)?
alveolar and embryonal rhabdomyosarcomas
the pediatric forms typically arise in the sinuses, head, neck, and GU tract
Pleomorphic rhabdomyosarcomas are in what patient pop?
adults
What is this?
pleomorphic rhabdomyosarcoma- more common in ADULTS and there are numerous, multinucleated bizarre eosinophilic tumor cells
What stains can comfirm a pleomorphic rhabdomyosarcoma?
Myogenin (IHC stain)
What is this?
alveolar rhabdomyosarcoma- seen in children and kind of looks like lung
What is this?
Embryonal rhabdomyosarcoma- seen in children and characterized by soft gray infiltrative mass compound of spindled and round cells in myxoid stroma
What is sarcoma botyoides?
A variant of embryonal rhabdomyosarcoma that develops in the wall of hallow mucosa lined area (nasopharynx and vagina) and form a CAMBLUM layer
What mutations are common in alveolar rhabdomyosarcoma? Which one has the worst prognosis?
t(1,13) and t(2,13)
with t(2,13)= worse prognosis
What is this?
Sarcoma botyoides (variant of embryonal rhabdomyosarcoma)
What is this showing?
In sarcoma botyoides, you seen a polypoid mass covered by mucosa, with an underlying hypercellular zone of pporly differentiated cells (cambium layer)
What are the tumors of smooth muscle?
- leiomyoma
- leiomyosarcoma
What is this?
Leiomyoma- a benign tumor of smooth muscle (the most common neoplasm in women)- tend to be positive for estrogen receptor
Image: Fascicles of densely eosinophilic spindle cells that often intersect at right angles
What causes Hereditary leiomyomatosis and renal cell cancer syndrome?
– germ line loss-of-function mutation in the fumerate hydratase (enzyme in Krebs cycle) gene
What is this?
Leiomyomas arise almost anywhere in the body, since smooth muscle is ubiquitous and rarely transform to leiomyosarcoma.
What is the most common location for a leiomyomas?
Uterus is the most common site; the wall of the uterus is made up of smooth muscle.
What is this?
Leiomyosarcoma - look at how non-uniform this looks
Where are leiomyosarcomas common?
Deep soft tissue of the extremities and retroperitoneum (more in women than men)
10-20% of soft tisse sarcomas
they are typically painless and can be large and bulky
Whats going on here?
Leiomyosarcoma metastatic to lung
T or F. Sarcomas tend to spread through the bloodstream (hematogenous spread) rather than through the lymphatic system
T, so one very characteristic place for them to metastasize to is the lungs, where the capillary bed acts as a filter for circulating tumor cells. Once filtered, some tumor cells are able to grow.
Pulmonary metastases are generally multiple, frequently numerous and tend to be larger and more numerous in the basal lower lobes because of the gradient in pulmonary arterial blood flow, which goes from highest in the bases to lowest in the apices.
Pulmonary metastases are a major cause of death for patients with sarcomas of all kinds.
What is a synovial sarcoma?
A misnomer, this tumor is of uncertain origin and can present in locations that lack synovium, often as painless deep seated masses for several years
these represent 10% of all soft tissue sarcomas
What is the most common mutation in synovial sarcomas?
t(X,18)
Facts about synovial sarcomas
most common in 20s-40s
METs common to lung and lymph nodes
Treatment: aggressive with limb-sparing surgery and often chemo
What is this?
Undifferentiated pleomorphic sarcoma- Malignant high grade waste basket – these tumors don’t fit anywhere and can not be identified based on histology, immunohistochemical profile, ultrastructure or molecular genetics.
Dx?
Giant cell tumor of tendon sheath
Dx?
Squamous cell carcinoma
What is this?
McCune Albright
Dx?
radiolucent nidus of osteoid osteoma
