Bone tumors. Flashcards
what are the benign bone tumors ?
osteoma
osteochondroma - tumor arises from the metaphysis of long bones such as distant femur and proximal tibia in children having laterally bony projection on x ray from the metaphysis
composed of mature hyaline cartilage and osseous tissue
osteoid osteoma ( osteoid is the unmineralized, organic portion of the bone matrix)
osteoblastoma
giant cell tumor
what are the malignant bone tumors ?
osteosarcoma
ewing sarcoma
what is osteoma ?
benign tumor composed of sclerotic well formed bone protruding from cortical surface of a bone
skull and facial bones
what is the treatment o osteoma ?
not premalignant no treatment required
if it causes swelling or bulge into air sinuses simple excision sufficient
what is osteoid osteoma?
a nidus of tangled arrays of partially mineralised osteoid trabecula
rim of highly vascularized, fibrous connective tissue
various degrees of sclerotic reaction seen around it
tibia most commonly affected and dispahysis of long bones
what is the treatment of osteoid osteoma ?
not premalignant - excision of nidus with sclerotic bone done
how does and osteoid osteoma differ from osteoblastoma ?
osteoid osteoma and osteoblastama are histologically the same but having giant cells and being bigger
what is the signs symptoms of osteoid osteoma ?
pain which is constant and progressive
palpable bone
how do we diagnose osteoid osteoma ?
generally on X-ray - visible zone of sclerosis surrounded by radiolucent nidus
how do we treat osteoid osteoma ?
complete excision of nidus with sclerotic bone
what is giant cell tumor ?
malignant variants are known
but mostly benign
tumor cosist of undifferentiated spindle cells interspersed with multinucleate giant cells arising from osteoclasts
the tumor stroma is highly vascularised
commonly affect the lower end of femur and upper end of tibia located at the epiphysis
what are the x ray findings of giant cell tumor ?
osteolytic lesions of the bone in CT and X-ray with soap bubble appearance
none or minimal reactive sclerosis
cortex may be thinned
what is osteosarcoma ?
malignant neoplasm of mesencymal cell origin producing malignant osteoid
commonly occurring in the lower end of femur
or upper end of tibia
can be osteoblastic - with a lot of new bone formation with pleomorphic osteoblasts
chondroid - cartilaginous cells
fibroblastic - contain undiffenatited fibroblasts
telangiectatic/osteolytic type
where does osteosarcoma usually metastasise to ?
to the lungs
what are the x ray features of osteosarcoma ?
medullary and cortical bone destruction
periosteal reaction - as the tumor lifts the periosteum it incites a periosteal reaction it is irregular unlike in osteomyelitis which is smooth
conman triangle - a triangular area of new subperiosteal bone when the tumor lesion breaks into the cortex and raises the periosteum away
sun ray appearance - as the periosteum is unable to contain the tumor
tumor grows into overlying soft tissue
and periosteal bone reaction stretch out perpendicularly within the tumor
