Flashcards in Tumours Deck (52):
most common site affected by osteosarcoma?
long-bone metaphyses around knee-distal femur and proximal tibia, and at proximal end of humerus
most common age group affected by osteosarcoma?
those aged between 15 and 20 years
appearance on X-ray of long bone affected by multiple myeloma?
moth eating- numerous lytic lesions
red flag signs in soft tissue sarcomas?
lump more than 5cm
deep to fascia- doesn't move with skin movement
which tumours commonly metastasise to bone?
kidney-high bleeding risk assoc with bony metasases
when should a pathological fracture resulting from a malignancy be suspected?
PAIN-especially before any trauma
inconsistency between resulting damage and degree of trauma
red flag symptoms of back pain?
age: under 18 or over 55yrs
non mechanical back pain
pain that worsens when patient supine
systemic features-fever, weight loss
history of malignancy
history of steroid use
what approach should be taken in any case of a pathological fracture due to metastatic disease?
MDT approach- require input of orthopaedic surgeons, oncologists, radiologists, pathologists, nurses, palliative care team, pharmacists etc.
complications of long bone pathological fractures?
slow functional recovery
all risks reduced with prophylactic fixation-e.g. use of an intramedullary BEFORE any pathological fracture occurs
how is the risk of a pathological fracture predicted?
presence of significant functional pain
more than 50% destruction of cortical bone
formal staging-Mirel's criteria
high stress anatomical regions e.g. proximal femur
why might embolisation be required prior to bone surgery for a metastasis?
some secondary disease very vascular so high bleeding risk
bone profile components?
albumin-important as high proportion of calcium bound to albumin so if albumin low, total calcium may be misleading e.g. in liver cirrhosis and nephrotic syndrome.
if a 55 yr old female was to suffer a fracture after minimal trauma, and her bone profile was found to be normal, what pathology might you expect to have predisposed her to the fracture?
Mirel's criteria can be used to predict the risk of a pathological fracture to determine whether prophylactic bone fixation should occur. what are it's components?
dependent on 4 features:
site of bone lesion: upper limb=1, lower limb=2, peritrochanteric=3
size of lesion: less than 1/3=1, 1/3-2/3=2, more than 2/3=3
bone lesion type: blastic=1, mixed=2, lytic=3
pain: mild=1, moderate=2, functional=3
score more than 8 suggests prophylactic fixation
before carrying out a prophylactic fixation for a bony malignancy, why is it important to know if the malignancy is primary or secondary?
fixation is NOT a curative procedure for the cancer, but if a tumour was found to be primary, there may be a higher likelihood of cure so you would not want to put in an intramedullary nail which will cause the cancer to spread to involve the whole bone and reduce the ability to perform limb-salvage surgery.
a BIOPSY showing a primary bone tumour e.g. sarcoma, may benefit from neoadjuvant chemo/radiotherapy
so do NOT perform prophylactic fixation until BIOPSY confirmed primary neoplasm of bone has been ruled out
goals of fixation in prophylaxis of pathological fractures in bony metastases?
maximise ability for immediate mobilisation and weight bearing
protect entire bone in setting of systemic or metastatic disease
optimise implant choice in context of patient's overall prognosis
fixation for femoral neck and head metastatic lesions?
what can patients be given following prophylactic bone fixation for metastatic bone disease?
treat remaining tumour burden not removed at surgery
most common site for all bony metastases?
most common site for pathologic fracture secondary to bone metastasis?
in investigating pathological fractures, why should an X-ray of the WHOLE bone be taken?
malignancy may be in more than 1 location along the bone
plan for surgery-margins
preferred biopsy in pathological fractures?
investigations in suspected primary bone tumour?
FBC-anaemia-normocyctic with BM infiltration, macrocytic with multiple myeloma-arises from blood forming cells of the BM-plasma cells, so not strictly a primary bone Ca, myeloproliferative disorders, myelodysplasia, neutrophilia, thrombocytosis-reactive secondary to malignancy
Us and Es-multiple myeloma can damage renal function, may be poor renal function with renal tumour that has metastasised to bone
PSA-rule out prostate Ca metastasis to bone
CRP-usually raised with malignancy, and ESR-part of haematology sample, usually raised in osteosarcoma, raised part. in multiple myeloma-raised levels of plasma proteins-Igs
LFTs-ensure if raised ALP not result of liver disease
clotting profile-often abnormal in malignancy, and prior to surgery
urine-Bence Jones protein-rule out multiple myeloma
bone profile-serum ALP may be raised with osteosarcoma
plain X-ray-lump, bone destruction, cortical thickening, 'cyst' appearance-hazy and diffuse boundary suggests invasive tumour, stippled calcification inside a vacant area is characterisitc of cartilage tumours e.g. chondrosarcoma. Ca2+ raised in multiple myeloma.
CT-assess local extent of tumour, important for deciding how much tissue would have to be removed, CT chest/abdo/pelvis for staging
MRI-assess exact location and extent of tumour, relationship to surrounding structures-look for nerve, blood vessel and muscle involvement
PET scan, isotope bone scan-use of radioactive isotope, can evaluate extent of osteosarcoma and any metastatic spread
BIOPSY-needle, although open more reliable, after imaging as biopsy can distort images. tissue may require bacteriological as well as histological examination to rule out chronic osteomyelitis which may present with pain and swelling and show metaphysis destruction and periosteal new bone formation on X-ray, without systemic disease features if suppressed by prev Abx.
definition of a primary 'bone' tumour?
origin is mesenchymal cells
what conditions might mimic a bone tumour?
infection-periosteal reaction on X-ray also seen with malignancy
common bone tumour symptoms and signs?
must examine area of lymphatic drainage of a lump
complications of tumour biopsy?
malignant bone tumour highly sensitive to radiotherapy?
Ewing's sarcoma-originates from endothelial cells in the BM and presents in patients commonly between 10 and 20 years of age
define the difference between immunotherapy and chemotherapy
immunotherapy (biologic therapy): treatment stimulating the body's own IS to fight the cancer. uses substances made by the body or mimics them e.g. monoclonal antibodies and particular proteins*
main complications of radiotherapy?
postirradiation spindle-cell sarcoma
pathological fracture in WB bones
general ADRs of radiotherapy-sore skin, fatigue, hair loss
symptoms and signs of osteosarcoma?
PAIN-constant, worse at night, gradually increases in severity
o/e: swelling and local tenderness
palpable mass in late cases, and overlying tissues look inflamed-red, hot, swollen
why is leukaemia NOT a primary bone Ca?
it is a blood Ca, originating from the blood forming cells of the BM-white blood cells
features of osteosarcoma on imaging?
plain X-ray: lytic lesions, may be alternating areas of increased bone density, tends to affect long bone metaphyses around the knee and proximal humerus
poorly defined tumour margins
breaching of cortex, sunburst effect if streaks of new bone radiating out from cortex
periosteal reaction-new bone, reactive new bone in angle between periosteum and cortex-Codman's triangle
radio-isotope scan-skip lesions
pulmonary CT-about 10% of pts have pulmonary metastases by time they're 1st seen-haematogenous spread
multi-agent chemotherapy for 8-12 wks before surgery, then as long as tumour resectable and there are no skip lesions-skip metastases equivalent to stage III metastatic disease, carry out wide resection. can then replace that segment of bone with large bone graft or custom made implant. amputation may be more appropriate in some cases for cure or to achieve adequate local control.
continue chemo for another 6-12 mnths post op if bone specimen shows marked tumour necrosis (more than 90%) highlighting response to pre op chemo. substitute different chemotherapeutic agent if response poor.
may do lung wedge resection for lung metastases
what type of osteosarcomas are most common after the age of 50 yrs?
paget's sarcoma-malignant transformation of paget's disease of bone
treatment of paget's sarcoma?
often advanced at diagnosis with pulmonary metastases
can try radical excision and chemo, but low 5 yr survival
palliative radiotherapy may be preferable, espec. as chemo usually difficult as uncertain renal and cardiac function.
when should we do a frozen section in the case of a pathological fracture?
if we are suspecting metastatic disease
excision of a bone tumour would be considered if?
isolated primary and good prognosis- depends on grading of cells following biopsy-high grade more likely to recur and spread after surgical removal
in general, low grade intracompartmental lesions (not extending into interfascial or extrafascial planes) can be treated by wide excision without exposing the tumour.
high grade and confined to bone may need radical excision, with or without bone graft or prosthesis
amputation may be needed if high grade with extracompartmental spread of primary malignant tumour
RFs for osteosarcoma?
previous radiotherapy or chemotherapy-due to treatment itself and likely gene faults producing previous Ca role in this presentation
hereditary retinoblastoma-retinoblastoma tumour suppressor gene (Rb
paget's disease in older population-paget's sarcoma
parent who had rectal Ca or liver Ca
RFs for chondrosarcoma?
age-older than 35-40 ( most commonly pts in their 40s and 50s)
pre-existing benign osteochondroma or chondroma
hereditary multiple exostoses
RFs for Ewing's sarcoma?
congenital umbilical hernia
parent who had kidney Ca
1st degree relative with melanoma or bone Ca
2nd most common bone tumour in children?
sites most commonly affected by chondrosarcoma?
sites most commonly affected by Ewing's sarcoma?
presentation of chondrosarcoma?
gradually enlarging lump
pathological fracture if medullary lesion
results of imaging in chondrosarcoma?
plain X-ray: radiolucent area with central flecks of calcification
treatment of chondrosarcoma?
usually slow growing and metastasise late, so ideal case for wide excision and prosthetic replacment
amputation may be safer if not certain tumour can be removed without exposing it and causing unacceptable loss of function
does NOT respond to chemo or radiotherapy
clinical features of Ewing's sarcoma?
imaging results in Ewing's sarcoma?
plain X-ray: bone destruction predominantly mid diaphysis in contrast to metaphyses in osteosarcoma, may be new bone formation extending along shaft, sometimes appearing as fusiform bone layers around lesion-onion peel effect.
CT and MRI-large extraosseous component
radio-isotope scan-lesions elsewhere in skeleton
what diagnosis should be excluded as rapidly as possible in Ewing's sarcoma?
must identify malignant cells on biospy, and make distinction between this round-cell tumour and osteosarcoma.
treatment of Ewing's sarcoma?
prognosis always poor
radotherapy dramatic effect on tumour, but nor much enhancement of overall survival-70% if localised, 30% if lung metastases and 20% if other bones/BM involved
chemotherapy more effective-5 yr survival 50%
best results with combination: pre op neoadjuvant chemo, wide excision if favourable site, or radiotherapy followed by local excision if less accessible, then further course of chemo for a year.