Pathology Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What are the prognostic factors in bone tumour staging?

A

In order

  • Presence of metastases
  • Discontinuous tumour (skip lesion)
  • High grade (poorly differentiated)
  • Size
  • Depth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the prognostic factors in soft tissue tumour staging?

A

In order

  • Presence of metastases
  • Grade
  • Size
  • Depth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Most common site of metastasis from bone lesions and soft tissue sarcomas?

A

Lung

Chemotherapy is used to reduce or eliminate pulmonary mets by inducing apoptosis (programmed cell death)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is an osteotomy osteoma?

A

Definition:
A benign bone tumour with a central nidus (woven bone and osteoid with greatest mineralisation in centre, and sharp border of osteoblastic rimming) surrounded by a reactive zone (sclerosis)

Histology:

  • Mineralised woven bone
  • Regularly shaped nuclei containing little chromatin
  • Abundant cytoplasm
  • Appearances similar to osteoblastoma

Epidemiology:

  • Typically < 30 years old
  • M:F 3:1

Locations:
-Usually within diaphysis and cortex
-Prox femur > tibia>
Spine >hands (scaphoid and prox phalanges)>feet (talar neck)

Symptoms:
-Pain at night, increases with time
-Secondary to prostaglandin E2 prod and COX1/COX2 expression
= increase in number/size of unmyelinated nerve fibres within nidus
-Relieved by NSAIDS

Associated conditions:

  • Painful scoliosis, concave on lesion side (remove within 18 months in children < 11 years old)
  • Growth disturbances
  • flexion contractures

Diagnosis:

  • CT better than MR scan
  • Nidus < 1 cm (otherwise osteoblastoma)
  • Technetium bone scan = increased uptake

Treatment

  • 50% improve with NSAIDS
  • CT-guided radiofrequency ablation dominant treatment method (nidus heated to 80 degrees)
  • Surgery is near NV bundle/spinal cord (RFA contraindicated)

Prognosis:

  • Pain resolves in 3 years
  • Lesions spontaneously resolve in 5-7 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Histology of osteoid osteoma?

A

Histology:

  • Mineralised woven bone
  • Regularly shaped nuclei containing little chromatin
  • Abundant cytoplasm
  • Appearances similar to osteoblastoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Epidemiology and location of osteoid osteoma

A

Epidemiology:

  • Typically < 30 years old
  • M:F 3:1

Locations:
-Usually within diaphysis and cortex
-Prox femur > tibia>
Spine >hands (scaphoid and prox phalanges)>feet (talar neck)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which bone tumours and which soft tissue tumours is chemotherapy particularly used?

A

Adjuvant to limb salvage surgery for bone tumours

  • Osteosarcoma
  • Ewing’s sarcoma

Soft tissue tumours

  • Rhabdomyosarcoma
  • Synovial sarcoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does radiotherapy work and when is it used?

And what are the bony complications?

A

Radiotherapy reduces or eliminates local recurrence by inducing DNA damage

Radiotherapy used ALONE for:

  • Metastatic bone disease
  • Lymphoma
  • Myeloma
  • Sometime Ewing’s sarcoma

Radiotherapy used in COMBINATION with limb salvage surgery for:
- Soft tissue sarcomas

May be used PRE or POST operative.
Post op =
- Equal control rates
- Lower wound complications
- Higher incidence of post operative fibrosis

Bony complications:

  • Late stress fractures
  • Post-irradiation sarcomas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When is wide excision used alone?

A
  • Chondrosarcoma
  • Parosteal Osteosarcoma
  • Adamantinoma
  • Chordoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is intralesional resection/curettage used?

A
  • Giant cell tumour
  • Chondroblastoma
  • Osteoblastoma
  • Non-ossifying fibroma
  • ABC
  • LCH (Langerhan’s cells histiocytosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do benign bone tumours in children usually present?

A

Incidental finding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Commonest bone tumours by age?
< 5 years
< 30 years
> 50 years

A

< 5 years

  • Leukaemia
  • Osteofibrous dysplasia
  • Rhabdomyosarcoma

< 30 years

  • NOF (non-ossifying fibroma)
  • UBC (unicameral bone cyst)
  • Enchondroma
  • Osteoid osteoma
  • Fibrous dysplasia
  • Chondroblastoma
  • GCT (giant cell tumour)
  • Ewing’s sarcoma
  • Osteosarcoma

> 50 years

  • Bony mets
  • Myeloma / Lymphoma
  • Chondrosarcoma
  • Fibrosarcoma
  • Malignant fibrous histiocytoma
  • Paget’s disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Tumours associated with anterior cortex?

A

Osteofibrous dysplasia

Adamantinoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Tumours associated with posterior cortex of distal femur?

A

Parosteal osteosarcoma

Periosteal desmoid (aka tug lesion caused by repetitive stress at attachment of adductor magnus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which tumours present in the epiphysis?

A

GCT
Chondroblastoma
Clear cell Chondrosarcoma (femoral head)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which tumours present in the metaphysis?

A

Non-ossifying fibroma
ABC
Osteosarcoma

20
Q

Which tumours present in the diaphysis?

A
Osteoid osteoma
Osteoblastoma
Fibrous dysplasia
Eosinophilic granuloma
Ewing’s sarcoma
Multiple myeloma
21
Q

Symptoms and associated conditions of osteoid osteoma

A

Symptoms:
-Pain at night, increases with time
-Secondary to prostaglandin E2 prod and COX1/COX2 expression
= increase in number/size of unmyelinated nerve fibres within nidus
-Relieved by NSAIDS

Associated conditions:

  • Painful nonstructural scoliosis, concave on lesion side (remove within 18 months in children < 11 years old). Occurs due to paraspinal muscle spasm
  • Growth disturbances
  • flexion contractures
22
Q

Imaging of osteoid osteoma

A

Diagnosis:

  • CT better than MR scan
  • Nidus < 1 cm (otherwise osteoblastoma)
  • Technetium bone scan = increased uptake
23
Q

Treatment and prognosis of osteoid osteoma

A

Treatment

  • 50% improve with NSAIDS
  • CT-guided radiofrequency ablation dominant treatment method (nidus heated to 80 degrees)
  • Surgery is near NV bundle/spinal cord (RFA contraindicated)

Prognosis:

  • Pain resolves in 3 years
  • Lesions spontaneously resolve in 5-7 years
24
Q

What are the principles of biopsy?

A
  • Use longitudinal incisions and excise the biopsy tracts
  • Maintain meticulous haemostasis (tourniquet, diathermy). Only in rare cases use small drain in corner of wound to prevent haematoma formation
  • Approach lesions through muscles if possible
  • Avoid functionally important and NV structures
  • Intraoperative frozen section analysis should be performed to ensure that adequate diagnostic tissue is obtained
  • Samples should be sent for bacteriologic analysis
25
Q

What are the 4 surgical margins of tumour excision?

A

1) Intralesional
2) Marginal (through reactive zone)
3) Wide (including a cuff of normal tissue)
4) Radical (entire tumour and its compartment removed, including surrounding muscles, ligaments and connective tissues)

26
Q

What are the 2 essential criteria for limb salvage surgery?

A
  • Outcome of local control is at least equal to that of amputation
  • Limb must be functional
27
Q

What tumours are associated with following genes?

Tumour suppressor genes (Retinoblastoma (RB) and p53)
t(11,22), gene product EWS-FLI1
t(X,18), gene product SYT-SSX1 and 2
t(12,16), gene product FUS-CHOP
t(2,13), gene product PAX3-FKHR
GNAS1 - activating mutation of the GS alpha surface protein

A

Tumour suppressor genes (Retinoblastoma (RB) and p53 - Li Fraumeni syndrome) = OSTEOSARCOMA

t(11,22), gene product EWS-FLI1 = EWING’S SARCOMA

t(X,18), gene product SYT-SSX1 and 2 = SYNOVIAL SARCOMA

t(12,16), gene product FUS-CHOP = MYXOID LIPOSARCOMA

t(2,13), gene product PAX3-FKHR = ALVEOLAR RHABDOMYOSARCOMA

GNAS1 - activating mutation of the GS alpha surface protein = FIBROUS DYSPLASIA

28
Q

How do soft tissue tumours present clinically and on MR scan?

What MR features are worrying?

How should they be worked up?

A

Painless or painless enlarging mass

On MR scan

  • well defined (pseudocapsule) and heterogenous
  • Low intensity on T1, high intensity on T2

Any large (> 5 cm) soft tissue mass, which is deep to the fascia, should be considered a sarcoma

Metastatic work up includes CT chest
CT abdo/pelvis required for liposarcomas because of synchronous retroperitoneal liposarcoma

29
Q

Most common sarcoma of the hand?

Most common sarcoma of the foot?

A

Hand —> Epithelioid sarcoma

Foot —> Synovial sarcoma

30
Q

Which soft tissue sarcomas usually metastasise?

Where do they usually metastasise to?

A

Sarcomas that usually metastasise —> Pneumonic ESARC

  • Epithelioid
  • Synovial
  • Angiosarcoma
  • Rhabdomyosarcoma
  • Clear cell

Lymphatic metastasis occurs in 5% of sarcoma cases

Most metastases to lungs

31
Q

Name 4 fibrous tissue tumours

A

Extra-abdominal desmoid tumours

Nodular fasciitis

Undifferentiated pleomorphic sarcoma (previously known as malignant fibrous histiocytoma)

Fibrosarcoma

32
Q

What is an extra-abdominal desmoid tumour?

A
  • “Rock hard” clinically
  • 10,000 fold increased risk of developing in Gardner’s syndrome (familial adenomatous polyposis)
  • Estrogen beta receptor inhibitors used for treatment
  • Treat with wide margin resection but recurrence is common
33
Q

What is nodular fasciitis?

A

15-35 years of age, M=F

Most common fibrous soft tissue lesion
Reactive lesion

Half of the lesions present in upper extremity

Painful rapidly enlarging mass over 1-2 weeks

Avid enhancement with gadolinium, inhomogenous mass
Nodularity with extension across fascia planes

Treatment —> marginal resection

34
Q

What is an undifferentiated pleomorphic sarcoma?

Previously known as malignant fibrous histiocytoma

A

Most common malignant soft tissue sarcoma in adults

Similar to Fibrosarcoma

Presents as enlarging painless mass

MR - deep seated inhomogenous mass, low T1 and high T2 signal

Histology - spindle and histiocytic cells arranged in stroiform (cartwheel) pattern

Treatment - wide marginal excision and adjuvant radiotherapy (latter if tumour > 5 cm)

35
Q

What is a Fibrosarcoma?

A

Malignant tumour, 30-80 years old

Painless enlarging mass

MR —> inhomogenous mass

If lesion in bone (rather than soft tissue) —> X-ray reveals permeating pattern, and bone scan very hot

Histology —> Tissue organised in herringbone fashion
Spindle cells separated by interwoven collagen fibres

Treatment —> wide local resection with perioperative radiation (latter if tumour > 5 cm)

36
Q

Name 3 tumours of fatty tissue?

A

Lipoma
Myxoid liposarcoma
Liposarcoma

37
Q

What is a lipoma?

A

A common benign tumour of mature fat cells

M>F, 40-60 years

Location:
Subcutaneous, INTERmuscular or INTRAmuscular

Painless slow-growing mass

MR:
Well demarcated lesion, with high T1/T2 signal and low signal on fat suppression sequences

Histology:
Acellular mature fat

LIPOMAS DO NOT PREDISPOSE A PATIENT TO LIPOSARCOMA

Treatment:
Observation
Excision if…
- Symptomatic —> local recurrence uncommon
- Rapidly growing
- Deep or retroperitoneal as increased risk of liposarcoma

38
Q

What is a liposarcoma?

A
Definition:
A heterogenous class of sarcomas with differentiation towards adipose tissue

Epidemiology:
M>F, 50-80 years

Location:
Commonly in lower extremity and retroperitoneum

Histology:
Thicker and more irregular septa than lipomas
The Lipoblast (signet-ring type cell) is pathognomic

Higher grade = increased metastasis risk

Types:

  • Well differentiated
  • Myxoid (intermediate grade) = most common (50%), t(12;16) chromosomal translocation
  • Round cell
  • Pleomorphic
  • Dedifferentiated

Treatment:

1) well differentiated —> marginal resection only
2) Others —> wide surgical resection with adjuvant radiotherapy