Chondrosarcoma is a primary, malignant bone tumour characteristically configuring a cartilaginous matrix demonstrating chondrocytes embedded within distinct lacunae. Chondrosarcoma frequently incriminates pelvic bones, femur, or humerus. Chondrosarcoma depicts genomic mutations within IDH1 and IDH2 genes, TP53, aneuploidy and active signalling pathways incorporating RB1, CDKN2A or CDK. Neoplasm exemplifies clinical symptoms such as pain, localized swelling or enlarging tumefaction. Variably and preponderantly cellular chondrosarcoma exhibits significant nuclear atypia, mitotic activity and a lobular or diffuse tumour configuration. An abundant cartilaginous matrix with embedded chondrocytes permeating lacunae or inter-trabecular spaces is observed. Chondrosarcoma requires segregation from chondroblast osteosarcoma, enchondroma, fracture callus or chondromyxoid fibroma. Surgical extermination of neoplasm along with removal of broad perimeter of uninvolved tissue is optimal.
Chondrosarcoma is a locally aggressive, primary, malignant bone tumour characteristically configuring a cartilaginous matrix with chondrocytes embedded within distinct lacunae. Chondrosarcoma contributes to ~20% of primary, malignant bone tumours and follows osteosarcoma in frequency. Conventional chondrosarcoma is sub-classified into primary, secondary, and periosteal chondrosarcoma. Periosteal chondrosarcoma may be denominated as juxta-cortical chondrosarcoma. Low grade neoplasms may be scripted as low grade, cartilaginous neoplasm. Chondrosarcoma grade I is designated as atypical cartilaginous tumour and commonly incriminates appendicular skeleton. Mesenchymal and clear cell chondrosarcoma may infrequently be observed [1,2].
Primary chondrosarcoma incriminates elderly population or middle-aged individuals whereas secondary and periosteal chondrosarcoma implicates younger subjects. A male predominance is observed. Chondrosarcoma frequently incriminates pelvic bones, femur, and humerus. Additionally, tumefaction is observed within trunk, skull, or facial bones. Small bones of hands and feet are exceptionally involved. Periosteal chondrosarcoma incriminates metaphysis of long bones as distal femur or humerus [1,2]. Conventional chondrosarcoma frequently emerges within the larynx.
Around ~50% chondrosarcomas depict genomic mutations within IDH1 and IDH2 genes. Tumours of advanced grade demonstrate aneuploidy. Besides, chromosomal mutations within TP53 and associated active signalling pathways incorporating RB1, CDKN2A or CDK may emerge within high grade chondrosarcomas. Primary chondrosarcoma is a neoplasm of obscure aetiology and appears devoid of pertinent benign precursor lesions [1,2]. Secondary chondrosarcoma may arise due to malignant metamorphosis of benign precursors. Central secondary chondrosarcoma emerges within pre-existing enchondroma whereas peripheral secondary chondrosarcoma occurs within pre-existing cartilaginous cap of an osteochondroma [1,2].
Enhanced possible emergence of secondary chondrosarcoma is discerned with Ollier’s disease and Maffucci syndrome. Periosteal chondrosarcoma arises upon the surface of bone in association with bony periosteum [1,2]. Chondrosarcoma exemplifies clinical symptoms such as pain, localized swelling, and enlarging tumefaction. Neoplasms incriminating skull base may demonstrate neurological symptoms. Enchondroma or osteochondroma may undergo malignant metamorphosis indicated by altered tumour magnitude or cogent clinical symptoms [1,2].
Grossly, neoplastic hyaline cartilage appears lobular. A cut surface demonstrates a grey/tan appearance with and foci of myxoid or mucoid substance. Focal mineralization
enunciates chalky deposits of calcium. Erosion of bony cortex
and neoplastic infiltration into circumscribing soft tissue ensues
[1,2]. Secondary peripheral chondrosarcoma delineates a thick
cartilaginous cap of magnitude ~2 centimeters incorporated
with cystic cavities. Periosteal chondrosarcoma manifests as an
enlarged, lobulated tumefaction adhering to surface of subjacent
The frozen section exemplifies nodules of hyaline cartilage
representing variable atypia. Low grade tumefaction can be
nomenclated as ‘low grade cartilaginous neoplasm’ [1,2]. Upon
cytological examination, an abundant extracellular matrix
appears admixed with definitive lacunae permeated with binucleated
or multinucleated chondrocytes. Atypical cartilaginous
tumour or grade I chondrosarcoma morphologically simulates an
enchondroma [1,2]. Grade II or III chondrosarcoma is cellular and
composed of cells with significant cytological and nuclear atypia
intermingled within abundant myxoid matrix [1,2].
In contrast to primary chondrosarcoma, metastatic
chondrosarcoma is adequately discerned upon cytological
examination [1,2]. Upon microscopy, tumefaction is variably and
preponderantly cellular with significant nuclear atypia and mitotic
activity. Contingent to grade, neoplasm exhibits lobular or diffuse
pattern of tumour configuration. An abundant cartilaginous
matrix demonstrates chondrocytes embedded within lacunae
with permeation of inter-trabecular spaces.
Foci of myxoid alterations and tumour necrosis are observed.
Chondroid matrix may demonstrate liquefaction. The low grade,
secondary peripheral chondrosarcoma may configure nodules
and cystic cavities [1,2]. Periosteal chondrosarcoma commonly
manifests as low grade, grade I or grade II neoplasm confined to
extraneous bony surface. Foci of infiltration into bony cortex or
circumscribing soft tissue and tumour magnitude > 5 centimeters
favors a malignant tumefaction, in contrast to periosteal
chondroma [1,2] (Figure 1 & 2).
a) Grade I composed of low grade, locally aggressive
neoplasm with a nodular pattern of tumour evolution,
denominated as atypical cartilaginous tumour. Grade I lesion
simulate normal cartilage or benign enchondroma. Distinction
between benign and malignant tumefaction is contingent to
detection of ‘chondrosarcoma permeation pattern’ with tumour
infiltration through bone marrow cavity. Grade I chondrosarcoma
is minimally or moderately cellular wherein neoplastic cells
demonstrate plump, uniform, hyperchromatic nuclei. Bi-nucleate
nuclei are occasionally discerned.
b) Grade II exemplifies moderately cellular neoplasms
with diffuse pattern of tumour progression. Nuclear atypia with
hyperchromatic nuclei, altered nuclear magnitude and mitotic
activity is discernible.
c) Grade III enunciates neoplasms of enhanced cellularity.
Tumour cells are preponderantly atypical, pleomorphic and
depict frequent mitotic activity. Neoplastic cells confined to
periphery of tumour lobules appear spindle-shaped and minimally
d) Grade IV manifests dedifferentiated chondrosarcoma
(~10%) morphologically demonstrating a high grade,
pleomorphic, spindle-shaped tumefaction devoid of significant
cartilaginous matrix and associated with an adverse prognosis
Chondrosarcoma is immune reactive to S100 protein and
D2-40. Chondrosarcoma is immune non-reactive to cytokeratin
[3,4]. Chondrosarcoma requires segregation from neoplasms
such as chondroblastic osteosarcoma, enchondroma, fracture
callus or chondromyxoid fibroma [3,4]. Chondrosarcoma can be
appropriately discerned with pertinent imaging techniques as
plain radiographs, computerized tomography (CT) and magnetic
resonance imaging (MRI) along with cogent surgical tissue
sampling (Tables 1 & 2).
Radiographic assessment of low-grade neoplasms is
mandatory and beneficial [3,4]. Upon plain radiography, tumour
exhibits popcorn-like calcification manifesting as punctate or
ring-like opacities, lytic lesions, endosteal scalloping, thickened
bony cortex with cortical erosion or destruction and incrimination
of circumscribing soft tissue [3,4].
Cortical destruction and infiltration of surrounding soft tissue
within pre-existing enchondroma may indicate emergence of
secondary central chondrosarcoma [3,4]. Secondary peripheral
chondrosarcoma exhibits a dense cartilaginous cap exceeding
>2-centimetre thickness. Periosteal chondrosarcoma denominates
a multi-lobulated countenance [3,4]. Computerized tomography
and magnetic resonance imaging are beneficial in assessing extent
of tumour [3,4].
Chondrosarcoma is appropriately treated with surgical
extermination of neoplasm along with removal of broad
perimeter of uninvolved tissue. Low grade chondrosarcoma
may be completely alleviated with precise surgical intervention
[3,4]. Generally, chondrosarcoma is resistant to chemotherapy
and radiotherapy although cartilaginous neoplasms mandate
intense radiation therapy [3,4]. Surgical extermination of highgrade
chondrosarcoma followed by adjuvant radiotherapy is
accompanied by superior outcomes. Prognostic outcomes are
contingent to factors such as histologic grade, extra-compartmental
tumour dissemination and localized tumour reoccurrence [3,4].
Atypical cartilaginous tumour or chondrosarcoma grade I is
locally aggressive and exhibits superior prognostic outcome with
5-year proportionate survival at ~85% [3,4]. Chondrosarcoma
grade II or grade III enunciate an inferior prognosis with 5-year
proportionate survival at ~50%. Localized tumour reoccurrence
is contingent to tumour magnitude, adequacy of surgical resection
and tumour free tissue perimeter [3,4].