Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts
of the bodyCarcinoma vs Sarcoma.
EPIDEMIOLOGY
Bone and soft tissue sarcomas comprise a family of tumours derived from mesenchymal tissue. Even when
considered together, they are rare comprising less than 1% of all new cancer diagnoses.
Soft-tissue sarcomas occur comparatively more frequent than bone sarcoma.
The incidence of bone and soft-tissue sarcomas is marginally higher in males than females.
In the case of soft-tissue sarcomas, the incidence increases with age . In contrast, bone sarcomas
demonstrate a bimodal distribution in both males and females, with peaks of incidence seen in both
definition teenage/adolescent years and the elderly
🔺
🔹Musculoskeletal Neoplasia are RARE!!!
🔹Average orthopaedist sees one malignant case every 5 years or so!
🔹Metastatic Carcinoma is 100x more common!
Benign lesions are some 4x more common than malignant lesions!
Primary bone tumours may arise in all sites but have preponderance for certain anatomical locations.
More than 60% of tumours of bone will arise from the long
bones of the lower limb, particularly around the knee. A further 18% will arise from the bones of the pelvis,
sacrumor coccyx, and a further 13% from the upper limb or shoulder girdle
PHEMISWER'S LAW:
Lesions of Bone occur in aneas of greatest bony actvity
Areas of Greatest Bone Growth:
-proximal tbia
-distal femur
-roximal humerus
-distal radius
-proximal femur
Tumors of bone and soft tissue are classified on the basis of
their principle cell type.
Generally, the higher the grade, the more cellular the tumour.
Higher-grade lesions have a >25% risk of local recurrence and
distant spread, whereas low-grade lesions a <25% risk of local
recurrence and metastases.
Staging is the process of assessing the extent of a tumour both locally and distantly.
As a consequence of most bone and soft-tissue sarcomas metastasizing via the
bloodsream, the lungs are the most common site for metastases, although other sitesmay
include bone, lymph nodes, liver and other soft-tissue locations.
The basis of all staging systems relies on knowledge of the grade of the tumour (a
measure of the aggressiveness of the tumour - high, intermediate or low), the size of the
tumour, the local extent, and the presence of metastases.
The Enneking stages are:
CLASSIFICATION Stage 1A Low-grade, intra-compartmental tumour
Stage 1B Low-grade, extra-compartmental tumour
Stage 2A High-grade, intra-compartmental tumour
Stage 2B High-grade, extra-compartmental tumour
Stage 3 Any of the above with metastases
More recently, the more conventional tumour- node metastasis (TNM) staging has
been applied to primary sarcomas of bone.
This system has, however, gained favour for the staging of soft-tissue sarcomas and has
A benign lesion of bone is defined as one that does not been adopted by the American Joint Committee on Cancer (AJCC), and the Union for
invade surrounding tissue or spread elsewhere in the body. International Cancer Control (UICC) In this system, size is dichotomized to small (<5 cm
Benign lesions can demonstrate a wide variety of behaviours: for soft-tissue sarcomas, <8 em for bone sarcomas) or large (>5 em for soft-tissue
-latent or inactive (e.g. non ossifying fibroma), sarcomas, >8 am for bone sarcomas).
-active, with a higher risk of recurrence after treatment
(e.g.aneurysmal bone cyst). The TNM stages are:
-Intermediate (locally aggressive) lesions of bone can destroy Stage IA Low-grade, small, no metastases
bone and surrounding tissue (e.g. osteoblastoma). STAGING--------> Stage 1B Low-grade, large, no metastases
-Intermediate (rarely metastasizing) lesions often behave in a Stage 2A Intermediate- or high-grade, small, no metastases
similar way to locally aggressive lesions but occasionally Stage 2B Intermediate-grade, large, no metastases
demonstrate the ability to spread to distant sites. Stage 3 High-grade, large, no metastases
The risk of such spread is <2%, is often not fatal and is not Stage 4 Any with metastases
reliably predictable from the histological appearance.
The classic example is the giant cell tumour of bone.
Regardless of the system adopted, the stage of disease has clinical significance to both
the patient and the clinician due to the association of poorer prognosis with advanced-
stage disease .
Staging allows prediction of prognosis which improves communication and classification
between units and between patients and clinicians.
Physicians, particularly those dealing with children and adolescents, must maintain a high index of
🔹
suspicion for malignancy.
Patients may be asymptomatic until the lesion is discovered incidentally on radiographs, common for
benign lesions, or for malignant lesions arising in areas where there is room for innocuous expansion, such
🔹
as the pelvis, where tumours can achieve a very large size prior to presentation
Age is often a consistent feature for primary bone tumours;
-osteosarcoma and Bwing's sarcoma have preponderance for children, adolescents and young adults,
- chondrosarcoma typically occurs in older patients.
-With increasing age, the likelihood of a lesion of bone being the result of metastatic disease increases
and the investigation of any pathological lesion of bone in an elderly patient must include an attempt to
🔹
identify a potential primary malignancy elsewhere
The most common symptom experienced by a patient with a bone tumour is pain The pain is initially
mild but then gets worse as the tumour increases in size. Night pain is a particularly worrying symptom
that should always cause concern.
Worrisome features from the history include pain, particularly night pain, pain not responding to simple
analgesia, persistent pain following injury, as well as prior benign or malignant
lesions, family history and previous radiotherapy.
🔹
A recent injury does not rule out a malignant pathology
🔹
The duration of symptoms prior to diagnosis is often measured in months and for slow-growing
tumours such as chondrosarcoma or chordoma in years. Swelling arises only when a tumour has
🔹
extended outside the bone and may initially be diflicult to detect.
Referred pain is not uncommon, particularly with pelvic tumours which can present with abdominal,
🔹
back or leg pain.
While paraesthesia or mumbness are suggestive of compression of a nerve by an expanding mass,
progressive neurological dysfunction is far more worrisome and is suggestive of direct tumour invasion.
CLINICAL PRESENTATION
🔹 Presentation with a pathological fracture has been reported in between 5 and 12% of osteosarcomas
and up to 21% of chondrosarcomas, and in the case of benign lesions is suggestive of a locally aggressive
🔹
lesion.
Prodromal symptoms of worsening functional pain are common and, in children in particular, a
musculoskeletal facture with a disproportionate level of injury (e.g. fall from standing height) should stimulate further
investigation. (Certain facture patterns should raise concern for an underlying lesion, such as
tumors supracondylar femoral fiactures in children, and avulsion fractures of the lesser trochanter in adults.
In elderly patients with diaphyseal long-bone fractures, the possibility of a pathological fracture should
🔹
be considered.
Clinical findings in the case of primary bone tumours are often non-specific. Swelling and tenderness
over the affected bone are the most common findings but there will be limitation of joint movement if
there has been irritation of the joint by the tumour, or the tumour has
🔹
grown into the joint.
Systemic findings are often rare except in extreme cases where presentation is very late and
dissemination has already occurred.
In the case of soft-tissue sarcomas, the majority present
as a painless, enlarging mass. The rapidity of enlargement is often suggestive of a malignant process,
though this does not accurately differentiate benign from a more sinister pathology.
All superficial soft-tissue lesions measuring greater than 5 cm and all deep-seated lesions should be
considered a sarcoma until proven otherwise
X-Rays ???
Computed tomography??
Magnetic resonance imaging??
by fatema okoff 🔹
Radionuclide scanning??
satellite lesions (a lesion distant from the tumour but within the reactive
zone of the tumour)
🔹
or
skip lesions (a lesion outside the reactive zone of the tumour but within
the same bone).
🔷 Evaluation: Radiography
PLAIN RADIOGRAPES IN TWO PLANES!
🔹
Enneking's ‘Big Four' (diagnosis of lesion)
🔹 Where is the lesion?
🔹 What is the lesion doing to the bone?
🔹What is the bone doing to the lesion?
Any additional clues? (matrix characteristics)
Investigating the ‘suspicious bone lesion':
🔹 🔹 🔹
The differential diagnosis of a bone abnormality will depend on the age of the patient, the location
🔹
of the lesion and the radiographic or MRI characteristics of the lesion.
Some lesions have absolutely typical presentations: for example:
-in a child an epiphyseal lesion is likely to be either a chondroblastoma or infection while at the same
location in an adult it is more likely to be a clear cell chondrosarcoma or a gaint cell tumor.
well demarcated lesions tend to be benign while ill-defined lesions are more likely to be malignant or
🔹
metastatic.
Metastases to bone are increasingly likely after the age of 35, particularly if the patient has a past
history of malignancy. However, 15% of patients with a bone lesion and a past history of cancer are found
to have a different cancer to the primary. Therefore, it is vital to assume nothing and keep an open
mind.
Always start with a thorough history and examination, looking, for instance, in an older patient at possible
🔹
symptoms or signs of other malignancy.
The usual primary sites that metastasize to bone are bronchus, breast, prostate, kidney and
thyroid
INVESTIGATIONS -If the diagnosis is not clear (to an experienced musculoskeletal radiologist) on plain X-rays, then further
investigation is warranted. Usually, this will consist of an MRI scan to delineate the extent of the lesion in
the bone and other tissues.
-If there is a suspicion of malignancy, then tests should be directed at identifying either a metastatic lesion
or an occult primary. CT scans of the chest, abdomen and pelvis will be helpful to identify occult primary
carcinomas.
-Biochemical tests will help to exclude prostate cancer (PSA)or myeloma (serum electrophoresis and
urinary Bence-Jones proteins) as possible causes.
- In older patients with the possibility of the lesion being metastatic, a bone scan is indicated to assess if
the esion is solitary or multiple .
-Other blood tests may give useful information (e.g raised calcium may indicate hyperparathyroidism,
or raised alkaline phosphatase may indicate Paget's disease which is a prognostic factors in
ostosarrcoma.
🔺
in the case of a suspected brown tumour, serum parathyroid hormone will be elevated.
Finally, it must be remembered that infection can be a great mimic of tumlours and it is good practice
to assess the CRP and ESR in all these patients.
Interestingly, these inflammatory markers have also been shown to be of prognostic value in a variety of
bone and soft-tissue tumours.
BIOPSY
Biopsy remains the gold standard for obtaining a diagnosis in an abnormal lesion of bone. principles that
🔹
must be considered:
🔹 The biopsy tract must be sited to minimize potential contamination of normal tissues .
🔹
🔹
The biopsy must be taken from representative tissue.
Image-guided biopsies should be used to reduce the risk of a sampling error.
🔹
🔹
Complete haemostasis must be achieved.
Samples should always be sent for microbiology as well as histology.
🔹
BONE TUMOUR MIMICS
🔹
▪️
The pathologist reporting the biopsy must have an appropriate level of experience.
If there is a risk of fracture following biopsy, the bone must be appropriately splinted. 🔹
🔹
Soft-tissue haematoma
Myositis ossificans
▪️
▪️
Fine needle aspirate accurate 70-75%
Core needle biopsy accurate 85% 🔹
🔹
Stress fracture
Tendon avulsion injuries
Open biopsy accurate 96-98%
🔹
🔹
Infection
Gout
🔹
🔹
Osteopetrosis
Osteopoikilosis
Melorheostosis
The management of patients with bone sarcomas must be carried out by a multidisciplinary team
-Knowledge of the natural history of all these lesions is essential to avoid both under- and over-treatment.
🔹 Benign lesion
-Latent benign lesions may not require any treatment unless symptomatic
-Active benign lesions usually require intervention to halt the active process and allow healing(biopsy and
curettage to detailed curettage and bone Grafting)
-Intermediate lesions present considerable challenges in management as recurrence is more common, and
ifthis arises, en- bloc removal of the lesion may be required to achieve local control.
Close follow-up is also required because of the risk of recurrence.
malignant lesion
🔹 Malignant tumours
require the full skills of the MDT to decide on optimum management. Many tumours will respond to
chemotherapy (e.g, osteosarcoma and Ewing's sarcoma) and most will require surgical resection. Patients
with a Ewing’s sarcoma or chordoma may also require highly specialized radiotherapy
PRINCIPLES OF MANAGEMENT OF
PRIMARY TUMOURS OF BONE
some benign musculoskeletal tumors
of the bodyCarcinoma vs Sarcoma.
EPIDEMIOLOGY
Bone and soft tissue sarcomas comprise a family of tumours derived from mesenchymal tissue. Even when
considered together, they are rare comprising less than 1% of all new cancer diagnoses.
Soft-tissue sarcomas occur comparatively more frequent than bone sarcoma.
The incidence of bone and soft-tissue sarcomas is marginally higher in males than females.
In the case of soft-tissue sarcomas, the incidence increases with age . In contrast, bone sarcomas
demonstrate a bimodal distribution in both males and females, with peaks of incidence seen in both
definition teenage/adolescent years and the elderly
🔺
🔹Musculoskeletal Neoplasia are RARE!!!
🔹Average orthopaedist sees one malignant case every 5 years or so!
🔹Metastatic Carcinoma is 100x more common!
Benign lesions are some 4x more common than malignant lesions!
Primary bone tumours may arise in all sites but have preponderance for certain anatomical locations.
More than 60% of tumours of bone will arise from the long
bones of the lower limb, particularly around the knee. A further 18% will arise from the bones of the pelvis,
sacrumor coccyx, and a further 13% from the upper limb or shoulder girdle
PHEMISWER'S LAW:
Lesions of Bone occur in aneas of greatest bony actvity
Areas of Greatest Bone Growth:
-proximal tbia
-distal femur
-roximal humerus
-distal radius
-proximal femur
Tumors of bone and soft tissue are classified on the basis of
their principle cell type.
Generally, the higher the grade, the more cellular the tumour.
Higher-grade lesions have a >25% risk of local recurrence and
distant spread, whereas low-grade lesions a <25% risk of local
recurrence and metastases.
Staging is the process of assessing the extent of a tumour both locally and distantly.
As a consequence of most bone and soft-tissue sarcomas metastasizing via the
bloodsream, the lungs are the most common site for metastases, although other sitesmay
include bone, lymph nodes, liver and other soft-tissue locations.
The basis of all staging systems relies on knowledge of the grade of the tumour (a
measure of the aggressiveness of the tumour - high, intermediate or low), the size of the
tumour, the local extent, and the presence of metastases.
The Enneking stages are:
CLASSIFICATION Stage 1A Low-grade, intra-compartmental tumour
Stage 1B Low-grade, extra-compartmental tumour
Stage 2A High-grade, intra-compartmental tumour
Stage 2B High-grade, extra-compartmental tumour
Stage 3 Any of the above with metastases
More recently, the more conventional tumour- node metastasis (TNM) staging has
been applied to primary sarcomas of bone.
This system has, however, gained favour for the staging of soft-tissue sarcomas and has
A benign lesion of bone is defined as one that does not been adopted by the American Joint Committee on Cancer (AJCC), and the Union for
invade surrounding tissue or spread elsewhere in the body. International Cancer Control (UICC) In this system, size is dichotomized to small (<5 cm
Benign lesions can demonstrate a wide variety of behaviours: for soft-tissue sarcomas, <8 em for bone sarcomas) or large (>5 em for soft-tissue
-latent or inactive (e.g. non ossifying fibroma), sarcomas, >8 am for bone sarcomas).
-active, with a higher risk of recurrence after treatment
(e.g.aneurysmal bone cyst). The TNM stages are:
-Intermediate (locally aggressive) lesions of bone can destroy Stage IA Low-grade, small, no metastases
bone and surrounding tissue (e.g. osteoblastoma). STAGING--------> Stage 1B Low-grade, large, no metastases
-Intermediate (rarely metastasizing) lesions often behave in a Stage 2A Intermediate- or high-grade, small, no metastases
similar way to locally aggressive lesions but occasionally Stage 2B Intermediate-grade, large, no metastases
demonstrate the ability to spread to distant sites. Stage 3 High-grade, large, no metastases
The risk of such spread is <2%, is often not fatal and is not Stage 4 Any with metastases
reliably predictable from the histological appearance.
The classic example is the giant cell tumour of bone.
Regardless of the system adopted, the stage of disease has clinical significance to both
the patient and the clinician due to the association of poorer prognosis with advanced-
stage disease .
Staging allows prediction of prognosis which improves communication and classification
between units and between patients and clinicians.
Physicians, particularly those dealing with children and adolescents, must maintain a high index of
🔹
suspicion for malignancy.
Patients may be asymptomatic until the lesion is discovered incidentally on radiographs, common for
benign lesions, or for malignant lesions arising in areas where there is room for innocuous expansion, such
🔹
as the pelvis, where tumours can achieve a very large size prior to presentation
Age is often a consistent feature for primary bone tumours;
-osteosarcoma and Bwing's sarcoma have preponderance for children, adolescents and young adults,
- chondrosarcoma typically occurs in older patients.
-With increasing age, the likelihood of a lesion of bone being the result of metastatic disease increases
and the investigation of any pathological lesion of bone in an elderly patient must include an attempt to
🔹
identify a potential primary malignancy elsewhere
The most common symptom experienced by a patient with a bone tumour is pain The pain is initially
mild but then gets worse as the tumour increases in size. Night pain is a particularly worrying symptom
that should always cause concern.
Worrisome features from the history include pain, particularly night pain, pain not responding to simple
analgesia, persistent pain following injury, as well as prior benign or malignant
lesions, family history and previous radiotherapy.
🔹
A recent injury does not rule out a malignant pathology
🔹
The duration of symptoms prior to diagnosis is often measured in months and for slow-growing
tumours such as chondrosarcoma or chordoma in years. Swelling arises only when a tumour has
🔹
extended outside the bone and may initially be diflicult to detect.
Referred pain is not uncommon, particularly with pelvic tumours which can present with abdominal,
🔹
back or leg pain.
While paraesthesia or mumbness are suggestive of compression of a nerve by an expanding mass,
progressive neurological dysfunction is far more worrisome and is suggestive of direct tumour invasion.
CLINICAL PRESENTATION
🔹 Presentation with a pathological fracture has been reported in between 5 and 12% of osteosarcomas
and up to 21% of chondrosarcomas, and in the case of benign lesions is suggestive of a locally aggressive
🔹
lesion.
Prodromal symptoms of worsening functional pain are common and, in children in particular, a
musculoskeletal facture with a disproportionate level of injury (e.g. fall from standing height) should stimulate further
investigation. (Certain facture patterns should raise concern for an underlying lesion, such as
tumors supracondylar femoral fiactures in children, and avulsion fractures of the lesser trochanter in adults.
In elderly patients with diaphyseal long-bone fractures, the possibility of a pathological fracture should
🔹
be considered.
Clinical findings in the case of primary bone tumours are often non-specific. Swelling and tenderness
over the affected bone are the most common findings but there will be limitation of joint movement if
there has been irritation of the joint by the tumour, or the tumour has
🔹
grown into the joint.
Systemic findings are often rare except in extreme cases where presentation is very late and
dissemination has already occurred.
In the case of soft-tissue sarcomas, the majority present
as a painless, enlarging mass. The rapidity of enlargement is often suggestive of a malignant process,
though this does not accurately differentiate benign from a more sinister pathology.
All superficial soft-tissue lesions measuring greater than 5 cm and all deep-seated lesions should be
considered a sarcoma until proven otherwise
X-Rays ???
Computed tomography??
Magnetic resonance imaging??
by fatema okoff 🔹
Radionuclide scanning??
satellite lesions (a lesion distant from the tumour but within the reactive
zone of the tumour)
🔹
or
skip lesions (a lesion outside the reactive zone of the tumour but within
the same bone).
🔷 Evaluation: Radiography
PLAIN RADIOGRAPES IN TWO PLANES!
🔹
Enneking's ‘Big Four' (diagnosis of lesion)
🔹 Where is the lesion?
🔹 What is the lesion doing to the bone?
🔹What is the bone doing to the lesion?
Any additional clues? (matrix characteristics)
Investigating the ‘suspicious bone lesion':
🔹 🔹 🔹
The differential diagnosis of a bone abnormality will depend on the age of the patient, the location
🔹
of the lesion and the radiographic or MRI characteristics of the lesion.
Some lesions have absolutely typical presentations: for example:
-in a child an epiphyseal lesion is likely to be either a chondroblastoma or infection while at the same
location in an adult it is more likely to be a clear cell chondrosarcoma or a gaint cell tumor.
well demarcated lesions tend to be benign while ill-defined lesions are more likely to be malignant or
🔹
metastatic.
Metastases to bone are increasingly likely after the age of 35, particularly if the patient has a past
history of malignancy. However, 15% of patients with a bone lesion and a past history of cancer are found
to have a different cancer to the primary. Therefore, it is vital to assume nothing and keep an open
mind.
Always start with a thorough history and examination, looking, for instance, in an older patient at possible
🔹
symptoms or signs of other malignancy.
The usual primary sites that metastasize to bone are bronchus, breast, prostate, kidney and
thyroid
INVESTIGATIONS -If the diagnosis is not clear (to an experienced musculoskeletal radiologist) on plain X-rays, then further
investigation is warranted. Usually, this will consist of an MRI scan to delineate the extent of the lesion in
the bone and other tissues.
-If there is a suspicion of malignancy, then tests should be directed at identifying either a metastatic lesion
or an occult primary. CT scans of the chest, abdomen and pelvis will be helpful to identify occult primary
carcinomas.
-Biochemical tests will help to exclude prostate cancer (PSA)or myeloma (serum electrophoresis and
urinary Bence-Jones proteins) as possible causes.
- In older patients with the possibility of the lesion being metastatic, a bone scan is indicated to assess if
the esion is solitary or multiple .
-Other blood tests may give useful information (e.g raised calcium may indicate hyperparathyroidism,
or raised alkaline phosphatase may indicate Paget's disease which is a prognostic factors in
ostosarrcoma.
🔺
in the case of a suspected brown tumour, serum parathyroid hormone will be elevated.
Finally, it must be remembered that infection can be a great mimic of tumlours and it is good practice
to assess the CRP and ESR in all these patients.
Interestingly, these inflammatory markers have also been shown to be of prognostic value in a variety of
bone and soft-tissue tumours.
BIOPSY
Biopsy remains the gold standard for obtaining a diagnosis in an abnormal lesion of bone. principles that
🔹
must be considered:
🔹 The biopsy tract must be sited to minimize potential contamination of normal tissues .
🔹
🔹
The biopsy must be taken from representative tissue.
Image-guided biopsies should be used to reduce the risk of a sampling error.
🔹
🔹
Complete haemostasis must be achieved.
Samples should always be sent for microbiology as well as histology.
🔹
BONE TUMOUR MIMICS
🔹
▪️
The pathologist reporting the biopsy must have an appropriate level of experience.
If there is a risk of fracture following biopsy, the bone must be appropriately splinted. 🔹
🔹
Soft-tissue haematoma
Myositis ossificans
▪️
▪️
Fine needle aspirate accurate 70-75%
Core needle biopsy accurate 85% 🔹
🔹
Stress fracture
Tendon avulsion injuries
Open biopsy accurate 96-98%
🔹
🔹
Infection
Gout
🔹
🔹
Osteopetrosis
Osteopoikilosis
Melorheostosis
The management of patients with bone sarcomas must be carried out by a multidisciplinary team
-Knowledge of the natural history of all these lesions is essential to avoid both under- and over-treatment.
🔹 Benign lesion
-Latent benign lesions may not require any treatment unless symptomatic
-Active benign lesions usually require intervention to halt the active process and allow healing(biopsy and
curettage to detailed curettage and bone Grafting)
-Intermediate lesions present considerable challenges in management as recurrence is more common, and
ifthis arises, en- bloc removal of the lesion may be required to achieve local control.
Close follow-up is also required because of the risk of recurrence.
malignant lesion
🔹 Malignant tumours
require the full skills of the MDT to decide on optimum management. Many tumours will respond to
chemotherapy (e.g, osteosarcoma and Ewing's sarcoma) and most will require surgical resection. Patients
with a Ewing’s sarcoma or chordoma may also require highly specialized radiotherapy
PRINCIPLES OF MANAGEMENT OF
PRIMARY TUMOURS OF BONE
some benign musculoskeletal tumors
