What is osteosarcoma ?
Highly malignant tumor arising from primitive
mesenchymal bone-forming cells.
Histologic hallmark is production of malignant
Mc histological form of primary bone cancer .
most common primary malignant bone tumor after
• Any bone can be involved but the Mc sites are – distal
femur, proximal tibia, proximal humerus.
• Mc metastasis to the lungs through blood stream.
More prevalent in males than female.
Involves any age but highest occurrence in adolescence
(sites of rapid bone growth)
Rapid bone growth – adolescence growth spurt in the
metaphyseal area near the growth plate.
Radiation exposure – mostly causes secondary forms.
Genetic predisposition :
- hereditary form of retinoblastoma( RB gene
- Li-Fraumeni syndrome (p53 gene mutation)
- Rothmund – Thomson syndrome ( autosomal
Paget's disease of bone – mostly secondary forms.
Osteosarcoma occurring at the site of another disease
more common in >50 years of age
most commonly a/w premalignant condition like
- Paget disease
- Previous radiation treatment
- Fibrous dysplasia
- Osteogenesis imperfecta
1. Conventional type: osteoblastic, chondroblastic &
2. Telangiectatic or osteolytic type OS
3. Small cell OS
4. Low grade central OS
5. Periosteal OS
6. Paraosteal OS
7. Secondary OS
8. High grade surface OS
9. Extra skeletal OS
Osteoblastic tumor – grayish white hard & gritty
feeling when cut.
Chondroid type – opalescent & bluish grey.
Fibroblastic – typical fish flesh sarcomatous
Telangiectatic – areas of tumor necrosis & blood
Stroma - Malignant
connective tissue with
anaplastic spindle cells in
Tumor cells surrounded by
osteoid matrix c/f
Osteoblastic – lot of new
fibrous – fibroblasts
Chondroid - cartilaginous
Pain– progressive pain particularly with activity.
Swelling - Palpable mass in the region of metaphysis.
- skin over the swelling shiny with prominent veins.
- swelling may be warm & tender.
Decreased range of motion of the involved joint.
Lymphadenopathy – unusual focal & regional lymph node
Respiratory finding – late stage with lung metastasis.
Fever & night sweats are rare. 12
Irregular destruction in metaphysis.
New bone formation.
Sunray appearance or hair on end
- tumor grows into the overlying soft tissue.
Codman’s triangle – area off sub periosteal new
bone formation seen at the area of
tumor -host cortex junction.
Codman triangle is a term
used to describe the
triangular area of
subperiosteal bone that is
created when a lesion, often
a tumor, raises the
periosteum away from the
• used to know the soft tissue extant.
• Not of much use in osteosarcoma.
CT chest to detect lung metastasis
• Determine vascularity of the tumour
• Detect vascular displacement
• Relationship of vessels to the tumour
A bone scan to look for skeletal
metastases or multi focal disease
Thallium scan - Monitor effects of
chemotherapy & Detect local recurrence
Full blood count, ESR, CRP.
LDH (elevated level is associated with
ALP (highly osteogenic)
Liver function tests
Renal function tests
to conform the diagnosis.
Fine needle aspiration
Core needle biopsy
Open incisional biopsy
Enneking staging system
The staging system is typically depicted as follows
Stage I: Low grade tumors
I-A intra compartmental
I-B extra compartmental
Stage II: High grade tumors
II-A intra compartmental
II-B extra compartmental
Stage III: Any tumors with evidence of
Painful radiologically lytic mass
lesion in the metaphyseal portion
of long bones.
Mc site – distal femur.
Histology - Blood filled vascular
spaces lined by osteoblasts.
Presents with local pain, soft tissue
mass & fractures.
d/d aneurysmal bone cyst.
Mets through hematogenous route
to bones & lung.
Arise from the periosteum.
Mc occurrence in adults.
Mc site Posterior metaphysis of
slow growing & late to metastasize.
Large ossified mass in centre.
Arises from diaphysis of long bones.
Mc femur & tibia
Presents with swelling & tenderness.
25% pathological fractures.
X-ray shows sunburst or hair on end
Histology – lobular & chondroblastic
Extent of the disease
Pts with pulmonary, non pulmonry (bone) or skip metastasis have
Grade of the tumor
High grade tumor have poor prognosis
Size of the primary lesion
Large size tumors have worse prognosis then small size tumors
proximal tumors do worse than distal tumors.
Secondary osteosarcoma: Poor prognosis
Biopsy to confirm diagnosis
Repeat radiological staging (access chemo response, finalize surgical
Surgical resection with wide margin
Reconstruction using one of many
Post op chemo based on preop response
Chemotherapy given preoperatively -Neoadjuvant
Given postoperatively - Adjuvant
Advantages of neoadjuvant chemotherapy -
regression of the primary tumor, making a successful limb
salvage operation easier.
may decrease the spread of tumor cells at the time of surgery
Effectively treating micro metastases at the earliest time possible.
It avoid tumor progression, which may occur during any delay
Given for about 3-4 weeks before definitive procedure
The drugs used most often to treat
Methotrexate with leucovorin (folinic acid)
Cisplatin or carboplatin
The main goal of surgery is to safely and
completely remove the tumor.
Historically – amputation.
Over the past few years - limb-sparing
procedures have become the standard, mainly due
to advances in chemotherapy and sophisticated
Limb salvage procedures now can provide rates of
local control and long-term survival equal to
Limb salvage surgery
Removing the tumor with a wide margin of
normal tissue surrounding it while preserving
vascular and nerve supply to the extremity.
The skeletal defect after limb salvage procedure must be
reconstructed by :
Autologous bone graft.
Endoprosthesis (most common)– replacing the removed
bone with a metal implant.
Rotationoplasty- after tumor rresection the distal portion of
the leg is rotated 180dgrees & reattached to the thigh at the
proximal edge of resection.
compromise between amputation and limb salvage
mc used for osteosarcoma of the distal femur in
skeletally immature patients.
It is a procedure where the neurovascular
structures and distal aspect of the limb (leg) are
retained, and re-attached to the proximal portion
after the tumor has been removed.
For e.g. the distal segment is turned 180 degrees so
that the ankle joint functions as a knee joint, thus
converting an above-knee to a below-knee
amputation in order for prosthetic use to be
Radiation therapy has no major role in
Radiation therapy may be useful in some cases
where the tumor cannot be completely removed
by surgery. E.g. in pelvic bones or in the bones of
Megavoltage (upto 6000-8000 rads)
Portion of the tumour is implanted in sarcoma
survivor & is removed after 14 days.
The sensitised lymphocytes from the survivor are
infused into the patient.
These cells selectively kill the cancer cells.
Follow up and Prognosis
Signs of recurrence, metastasis and treatment
Physical examination,radiographs of the primary
site, serial chest imaging,bone scans and
50 % cases with high grade osteosarcoma have
some type of relapse in 5 months
If recurrence is detected, additional surgery
(radical amputation)and chemotherapy may be
5 year survival rate is 5% - 23%