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Flashcards in Tumours Deck (52):
1

most common site affected by osteosarcoma?

long-bone metaphyses around knee-distal femur and proximal tibia, and at proximal end of humerus

2

most common age group affected by osteosarcoma?

those aged between 15 and 20 years

3

appearance on X-ray of long bone affected by multiple myeloma?

moth eating- numerous lytic lesions

4

red flag signs in soft tissue sarcomas?

lump more than 5cm
deep to fascia- doesn't move with skin movement
enlarging
painful

5

which tumours commonly metastasise to bone?

breast
prostate-osteoblastic lesions
kidney-high bleeding risk assoc with bony metasases
lung
thyroid

6

when should a pathological fracture resulting from a malignancy be suspected?

PAIN-especially before any trauma
inconsistency between resulting damage and degree of trauma
concomitant disease
abnormal X-ray

7

red flag symptoms of back pain?

age: under 18 or over 55yrs
non mechanical back pain
thoracic pain
pain that worsens when patient supine
night pain
systemic features-fever, weight loss
history of malignancy
history of steroid use

8

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.

9

complications of long bone pathological fractures?

slow functional recovery
implant failure
fracture non-union
blood loss
PE

all risks reduced with prophylactic fixation-e.g. use of an intramedullary BEFORE any pathological fracture occurs

10

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
osteolytic lesions

11

why might embolisation be required prior to bone surgery for a metastasis?

some secondary disease very vascular so high bleeding risk

12

bone profile components?

calcium, Ca2+
phosphate, PO43-
ALP
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.

13

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?

osteoporosis

14

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

15

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

16

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

17

fixation for femoral neck and head metastatic lesions?

hemiarthroplasty

18

what can patients be given following prophylactic bone fixation for metastatic bone disease?

post-op radiotherapy:
reduce pain
slow progression
treat remaining tumour burden not removed at surgery

19

most common site for all bony metastases?

spine

20

most common site for pathologic fracture secondary to bone metastasis?

proximal femur

21

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

22

preferred biopsy in pathological fractures?

needle biopsy

23

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.

24

definition of a primary 'bone' tumour?

origin is mesenchymal cells

25

what conditions might mimic a bone tumour?

haematoma
stress fracture
healing fracture
infection-periosteal reaction on X-ray also seen with malignancy

26

common bone tumour symptoms and signs?

pain
lumpy swelling
local tenderness

must examine area of lymphatic drainage of a lump

27

complications of tumour biopsy?

haemorrhage
infection
wound breakdown
pathological fracture

28

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

29

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*

30

main complications of radiotherapy?

postirradiation spindle-cell sarcoma
pathological fracture in WB bones

general ADRs of radiotherapy-sore skin, fatigue, hair loss

31

symptoms and signs of osteosarcoma?

PAIN-constant, worse at night, gradually increases in severity
lump
o/e: swelling and local tenderness
palpable mass in late cases, and overlying tissues look inflamed-red, hot, swollen

32

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

33

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

34

osteosarcoma treatment?

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

35

what type of osteosarcomas are most common after the age of 50 yrs?

paget's sarcoma-malignant transformation of paget's disease of bone

36

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.

37

when should we do a frozen section in the case of a pathological fracture?

if we are suspecting metastatic disease

38

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

39

RFs for osteosarcoma?

young age-10-20years
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
neurofibromatosis possibly*
down's syndrome
paget's disease in older population-paget's sarcoma
parent who had rectal Ca or liver Ca

40

RFs for chondrosarcoma?

age-older than 35-40 ( most commonly pts in their 40s and 50s)
male
pre-existing benign osteochondroma or chondroma
hereditary multiple exostoses
ollier's disease
maffucci's syndrome

41

RFs for Ewing's sarcoma?

age-young-10-20yrs
congenital umbilical hernia
parent who had kidney Ca
1st degree relative with melanoma or bone Ca

42

2nd most common bone tumour in children?

Ewing's sarcoma

43

sites most commonly affected by chondrosarcoma?

pelvis
scapula
rib cage
humerus
proximal femur
tibia

44

sites most commonly affected by Ewing's sarcoma?

femur
pelvis
tibia
fibula
clavicle

45

presentation of chondrosarcoma?

dull ache
gradually enlarging lump
pathological fracture if medullary lesion

46

results of imaging in chondrosarcoma?

plain X-ray: radiolucent area with central flecks of calcification

47

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

48

clinical features of Ewing's sarcoma?

pain-often throbbing
swelling

49

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

50

what diagnosis should be excluded as rapidly as possible in Ewing's sarcoma?

bone INFECTION
must identify malignant cells on biospy, and make distinction between this round-cell tumour and osteosarcoma.

51

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.

52

if secondary bone malignancy diagnosed, what treatment could be given?

prophylactic fixation with an intramedullary nail
radiotherapy