Chondrosarcoma (synonyms: chondroblastic sarcoma; chondroid sarcoma; chondromyxoid sarcoma; enchondroma malignum; cartilage sarcoma; malignant chondroid tumor; ICD-10-GM C41.9: Bone and articular cartilage, unspecified) is a malignant (malignant) neoplasm (neoplasm) of bone. The tumor cells of chondrosarcoma form a chondroid matrix (cartilage matrix) but, unlike osteosarcoma, do not form an osteoid (soft, not yet mineralized ground substance (matrix) of bone tissue/”immature bone”).
Chondrosarcoma is a primary bone tumor. Typical for primary tumors is their respective course and that they can be assigned to a certain age range (see “Frequency peak”) as well as a characteristic localization (see under “Symptoms – complaints”). They occur more frequently at the sites of most intensive longitudinal growth (metaepiphyseal/articular region). This explains why bone tumors occur more frequently during puberty. They grow infiltratively (invading/displacing), crossing anatomical boundary layers. Secondary bone tumors also grow infiltratively, but usually do not cross boundaries.
Chondrosarcomas can be classified as follows:
- Primary chondrosarcoma – cause unknown.
- Secondary chondrosarcoma – develops by malignant (malignant) transformation from benign (benign) bone tumors
(See also “Classification”).
If a chondrosarcoma occurs simultaneously at different sites in the body, it is called chondrosarcomatosis.
Sex ratio: males are more commonly affected than females.
Frequency peak: the disease occurs predominantly between the 30th and 60th year of life (clustered in the 6th decade of life).3rd degree chondrosarcoma (see under “Course and prognosis”) occurs predominantly < 30 years.
Malignant bone tumors account for 1% of all tumors in adults.Chondrosarcoma is the second most common malignant tumor of bone (20%) after osteosarcoma (40%).
Course and prognosis: Chondrosarcoma grows slowly, therefore symptoms usually occur only in the later course. Compared to other bone tumors, chondrosarcoma causes little pain.Chondrosarcoma can be divided into three degrees of differentiation. The more undifferentiated, the more malignant (malignant) the chondrosarcoma. A 1st grade (low grade) tumor grows slowly and forms virtually no metastases. A 2nd degree chondrosarcoma is already significantly more malignant and is associated with poorer chances of survival if metastases form. A 3rd degree chondrosarcoma (high grade) grows quickly and spreads rapidly. Approximately 60% of chondrosarcomas are 1st grade, 35% are 2nd grade, and 5% are 3rd grade.A chondrosarcoma metastasizes primarily to the lungs (hematogenous/via the bloodstream).It is chemo- and radiation-resistant. Consequently, surgical removal is the method of choice. The prognosis depends not only on the location and histological malignancy grade (degree of malignancy based on fine tissue examination) but also on the radicality of the surgical procedure.Chondrosarcoma can recur (recurrence of the disease) even after 10 years.
The 5-year survival rate for 1st degree chondrosarcoma (low malignancy and radical surgery) is 90%. After 10 years, between half to two-thirds of patients are still alive. The 10-year survival rate for 2nd-degree chondrosarcoma ranges from about 40 to 60% and for patients with 3rd-degree chondrosarcoma from 15 to about 35%.Dedifferentiated and mesenchymal chondrosarcomas have a poor prognosis. Most patients die within the first two years after diagnosis.
