Pathology: Malignant Bone Tumours Flashcards
what age group are primary bone tumours common in
younger
what do bony lesions in older population usually relate to
metastases from epithelial malignancies
describe the pain that metastatic cancer affecting the bone produces
severe and usually worse at night systemic symptoms may present
when do 1y bone tumours present
late - tend to have already metastasised some have an ill defined bony swelling
what is seen on X ray
cortical destruction, periosteal reaction, new bone formation and extension into surrounding soft tissue
what is a periosteal reaction
formation of new bone in response to periosteum (injury to)
most common form of primary bone tumour
osteosarcoma
what mutation are most osteosarcomas associated with
mutations in Retinoblastoma gene (tumour suppressor protein)
where do most osteosarcomas occur
60% bones around knee also proximal femur, proximal humerus and pelvis
what can prolong survival with osteosarcomas
chemotherapy
chondrosarcoma
cartilage producing primary bone tumour
what age group does chondrosarcoma tend to present in
older (45)
where do chondrosarcoma tend to occur
pelvis and proximal femur
describe the characteristics of chondrosarcoma
large and slow to metastasise compared to osteosarcomas which are fairly aggressive
what is the prognosis of chondrosarcoma dependent on
histological grade - majority low grade
what is the effect of radio and chemo therapy on chondrosarcoma
not effective
who is Ewings sarcoma most commonly seen in
teenagers , highly malignant
where do Ewings sarcomas tend to occur
along long bones
what is the radiological appearance of Ewings sarcoma
onion skin
what group do ewings sarcoma belong to
small round blue cell tumours - wide DD
what translocation is Ewings sarcoma associated with
t11:22 translocation involving EWS gene on chromosome 22
what CF is Ewings sarcoma assoicated with
fever, raised inflammatory markers and warm swelling (may be misdiagnosed as osteomyelitis)
is ewings sarcoma radio or chemo sensitive
both
outline the treatment of primary bone tumours
usually surgery to remove the tumour and surrounding tissue to prevent recurrence
amputations and limb salvage surgery also used
what are the staging investigations for primary bone tumours
bone scan and CT
chest MRI and CT are useful to determine the local extent of tumour and involvement of muscle and vessels etc
what must be done prior to surgery
biopsy for histological diagnosis grading
what must be done after surgery
joint involved needs reconstruction with special joint replacements
when are radio and chemo used
when appropriate neo- adjuvant chemo (prior to surgery) can improve survival
what is lymphoma called when it presents as a primary bone tumour
non hodgkins lymphoma
where does 1y lymphoma of the bone tend to affect
pelvis or femur
how does one treat 1y lymphoma of the bone
surgical resection
what CF may be present with metastatic lymphoma
lymphadenopathy or splenomegaly - treat with chemo/radio
where does myeloma arise from
marrow
what is a solitary lesion of myeloma referred to as
plasmacytoma
what are multiple lesions of myeloma referred to as
multiple myeloma
how does myeloma present
malignant clonal proliferation of abnormal plasma cells, these produce abnormal proteins called PARAPROTEINS (defective Immunoglobulin) that are deposited throughout many organ sites
what is deposition of abnormal proteins known as
amyloidosis
what is the amyloidosis known as in myeloma
AL amyloid - protein represents immunoglobulin light chain
what age are the patients with myeloma typically
45-65
how do patients with multiple myeloma typically present
weakness, back pain, bone pain, fatigue and weight loss
marrow suppression - anaemia and recurrent infection
pathological fracture
how is myeloma diagnosed
identification of the abnormal proteins either by plasma protein electrophoresis and/or early morning urine collection for Bence Jones protein assay
what will the plasma protein electrophoresis show in myeloma
high level of paraprotein
treatment of myeloma
solitary plasmacytoma - radio
multiple myeloma - chemo
name the primary malignant tumours that commonly metastasise to bone (in order of frequency)
breast
prostate
lung
renal
thyroid
what may the pain of bone metastases frequently be diagnosed as
muscle strain
how are fractures or impending fractures treated
stabilisation using long rods if destruction of the joint replacement may be better
The most common form of primary bone tumour, producing abnormal bone. Most cases are seen in younger age groups (adolescence and early adulthood) with 60% involving the bones around the knee.
osteosarcoma
A malignant tumour of unknown histogenesis characterised by the t(11;22) translocation.
ewings sarcoma
A malignant tumour that only rarely occurs in bone and usually only if the bone is abnormal (Paget’s etc.).
fibrosarcoma
