Chondrosarcoma is a malignant tumor of cartilage-producing cells which consist of a heterogeneous group of lesion with diverse morphological features and clinical behavior.
Chondrosarcoma is also called as tumor with hyperglycemia
It is the most common sarcoma of the bone greater than 20 years (25% of all sarcomas)
WHO Classification of Chondrosarcoma
- Primary and Secondary Chondrosarcoma
- Juxtacortical (Periosteal) Chondrosarcoma
- Dedifferentiated Chondrosarcoma
- Mesenchymal Chondrosarcoma
- Clear cell Chondrosarcoma
Primary Chondrosarcoma
90% of chondrosarcoma
Primary Chondrosarcoma is a malignant cartilage tumor arising centrally in a previously normal bone
It is 3rd most common after Myeloma and Osteosarcoma
It is also called Central / Conventional Chondrosarcoma
Etiology
Age: Adulthood ( Peak in 3rd- 7th decade)
Male > Female = 3:2
Site:- Pelvis is the most common site (Ilium), Proximal femur, Proximal humerus, distal femur, ribs
It is uncommon in small bones of hands and feet
Clinical Features
Pain
Pathological Fracture
X-Rays:
Expansion of the medullary portion of bone and thickening of the cortex
Periosteal reaction: absent/ scant
Endosteal scaffolding as well as annular, punctate, or comma-shaped stippled calcification (ring and arcs appearances)
Similar to Enchodromas
Endosteal scalloping of more than 2/3rd of the cortical thickness is suggestive of a more aggressive lesion.
It shows the different radiological lesions
| Adequate | Aggressive |
|---|---|
| Cortical Expansion with handling thickening | Cortical disruption + soft tissue masses |
Predictor of malignancy:- Localization of axial skeletal:- Size larger than 5 cm
Symptomatic intramedullary cartilaginous tumor but doesn’t shows adaptive aggressive signs: Low-grade chondrosarcoma/ Enchrondomas
The appearance of lysis in the previously calcified area: herald tumor prognosis
CT Scan
It helps in the detection and characterization of lesions in the anatomical complex areas, especially the sacrum, and spine.
MRI Scan
The intramedullary extension is best demonstrated
Bone Scan
Radionucleotide uptake in the lesion ( Grade from 1-3)
| Grade | Uptake |
|---|---|
| Grade 1 | Uptake less than that in ASIS |
| Grade 2 | Uptake similar to ASIS |
| Grade 3 | Uptake greater than ASIS |
PET Scan: To detect differentiation from benign
Laboratory Diagnosis
Non-specific
Not contract CT: Lung most common site for metastasis
Pathology
Gross features
Glistening, translucent, blue-gray, or blue-white
Calky white area of calcification
Microscopic features
Irregular lobules of cartilage which permeates the host
Hyaline cartilaginous matrix with a variable amount of myxoid changes
As per cellular atypia (3- Grades)
| Grade | Cellular atypia |
|---|---|
| Grade 1 | Moderately cellular (vis-a-vis enchondroma) |
| Grade 2 | More cellular shows more nuclear atypia |
| Grade 3 | Very cellular and shows pleomorphic and anaplastic tumor cells |
Treatment
Surgery is the only reliable treatment
It is not sensitive to chemotherapy and radiotherapy
Grade 1
In long bones (aggressive radiological features:- Wide excision)
Extended Intralesional curretage
It has advantageous function results that are superior to resection
The cartilaginous lesion in the pelvis and sacrum: Intralesional excision (Frequent reoccur)
Radiotherapy: Limited
Prognosis:
Most pulmonary metastasis within 5 years of initial presentation
Predictor of metastasis: Histological grade
Secondary Chondrosarcoma
Secondary chondrosarcoma is known to occur after being a precursor lesion
- Osteochondroma
- Enchondroma
Develop earlier than primary chondrosarcoma
Peripheral Chondrosarcoma: Malignant transformation within the cartilaginous cap
Clinical Features
The sudden onset of pain and increase in size suggests a malignant transformation in an enchondromas
X-Ray Features
Irregular mineralization and increased thickness of cartilaginous cap in osteochondromas
Pre-existing enchondromas: reveals destructive permeating of bone and development of a soft tissue mass
CT Scan/ MRI
Invasion of the surrounding tissue and marked myxoid changes
Pathology
Invasion of the surrounding tissue and marked myxoid changes
Treatment
Wide surgical excision of the lesion
Should not be violated ( cartilaginous cap):- during resection of tumor arising in osteochondromas
Periosteal Chondrosarcoma
It is also called Juxta-cortical chondrosarcoma
It arises from the outer surface, the highest incidence is seen in 4th decade
Radiological Features
Round in shape and lies on the surface of the bone with indistinct and irregular
Radiolucent lobulated lesion: Stippled calcification and tends to affect the metaphyseal cortex
Dedifferentiated Chondrosarcoma
Dedifferentiated Chondrosarcoma is the most malignant of all chondrosarcoma and has a very poor prognosis
It has two different pathological tissue components
- Well-differentiated cartilage tumor (Low-grade chondrosarcoma)
- High-grade non-cartilaginous sarcoma
Average age: 50-60 years
Male=Female
Mesenchymal Chondrosarcoma
Mesenchymal Chondrosarcoma is a biomorphic pattern- highly differentiated, small round cells and an island of well-differentiated hyaline cartilage
Craniofacial bones: Jaw Bones
Meninges: Most common site for extraskeletal involvement
Clear Cell Chondrosarcoma
Clear Cell Chondrosarcoma has a clinical behavior that is less aggressive than conventional chondrosarcoma
Predilection: Epiphyseal End of Long Bone
Histological it is characterized by the presence of bland clear cells in addition to the hyaline cartilage
Age predisposition: 25-50 years
2/3rd of the lesion: Femoral head or humerus head
Chordoma
Chordoma is a rare, low to the intermediate-grade malignant bone tumor of the cranium and spine.
1- 4 % of all bone malignancy
Age:
Spheno-occipital tumors (35-40%): Usually develop in young adults
Sacro-coccygeal tumors (40-50%): Develop after 40 years of age
No age in immune
Male: Female = 1.8:1
Clinical Features
Chordoma is a slow-growing tumor that is insidious in onset
Sacrococcygeal tumors show symptoms due to expansions and bone destruction
Presents with pain in the anal and rectal region
Pain is mild and intermittent in nature
Other features :
- Constipation
- Urinary difficulty
Neurological Deficit: More likely to occur in chordomas of the mobile spine than in the sacrococcygeal region
Skull bone Chordomas present with cranial nerve palsies and endocrinopathies and rarely epistasis and intracranial hemorrhages
X-Ray Features
X-ray features show mid-line lesion and often appears on plain radiographs as a destructive bone lesion with an epicenter in the vertebral body and surrounding soft tissue mass
Pathology
Microscopic Lobulated and shows fibrous septa
Have abundant: Clear cytoplasm ( Physaliferous cells)
Chondroid variant: Hyaline, myxoid cartilages
Tumor cells: S100 protein, pan-cytokeratin, EMA
Treatment options
Complete En-bloc surgical resection
Surgery is extensive, and necessary, sacrificing several sacral nerves at times resection of bowel loops with colostomy, complete sacral and bony reconstruction with allograft
The tumor is radioresistant, radiotherapy is done only for surgically inaccessible sites.
See also: Ewing Sarcoma
See also: Osteosarcoma
See also: Musculoskeletal Malignancy: Management
