Chondrosarcoma

All information given here is of general nature only, a tumor therapy always belongs in the hands of an experienced oncologist!

Synonyms

Cartilage sarcoma, malignant chondroid tumor, enchondroma malignum, chondroblastic sarcoma, chondromyxoid sarcoma, chondroid sarcoma English: chondroblastic sarcoma, chondrosarcoma

Definition

Chondrosarcoma is a malignant tumour derived from cartilage cells. In rare cases, a chondrosarcoma can also occur at different sites simultaneously. In these cases one speaks of chondrosarcomatosis. After osteosarcoma, chondrosarcoma is the most common malignant bone tumour.

Frequency

Chondrosarcoma is the second most common solid malignant (malignant) bone tumor, accounting for 20% of all cases. The peak of the disease lies in adulthood between the ages of 30 and 50, but in principle it can occur at any age.

Localization

Chondrosarcoma occurs preferentially in the following locations:Frequencies 23% Thigh 19% Ilium 5% Pubic bone 2% Ischium 10% Upper arm close to the shoulder 5% Shoulder bladeThe most frequent location of chondrosarcoma is thus close to the hip joint (thigh and pelvis) (49%). The second most common location is the shoulder region at 15%.

Cause

The cause of the primary chondrosarcoma is not clear. Chondrosarcoma are derived from highly differentiated cartilage cells. The more differentiated a tumour is, i.e. the more similar the tumour is under the microscope to the original cell, the more benign the tumour behaves.

Secondary chondrosarcomas develop from benign chondromas. The malignant degeneration of a single enchondrome is generally unlikely. The risk of degeneration increases with the number of enchondromes present.

The risk of degeneration of a single enchondrome is estimated at about 1%. However, there is a high risk of degeneration in enchondromatosis with or without Ollier’s disease and in Maffucci syndrome. If there are many osteochondromas, the risk of degeneration is estimated to be significantly higher at approx. 10%.

Metastasis

In most cases, chondrosarcoma is a tumour with a high degree of differentiation (see above). The transitions from a benign cartilage cell to a malignant tumour are fluid and often difficult to differentiate. A decrease in differentiation (similarity of the tumour tissue to the original tissue) is accompanied by an increase in malignancy.

To the same extent, the probability of metastases increases and the prognosis worsens. Therefore, differentiation is an important prognostic factor. Chondrosarcoma metastasizes primarily hematogenically into the lung.

There are many classifications that describe different subtypes. Essentially, differentiation is based on fine tissue examination under the macroscope. Primary chondrosarcoma:

  • Chondrosarcoma (conventional)
  • Dedifferentiated chondrosarcoma
  • Juxtacortical (periosteal) chondrosarcoma
  • Mesenchymal chondrosarcoma
  • Clear cell chondrosarcoma
  • Malignant chondroblastoma
  • Secondary chondrosarcoma

Differentiation

Especially if a tumour occurs close to the body, i.e. does not occur on the arms and legs, the probability of malignancy increases. Chondrosarcomas, which occur close to the trunk, usually have different districts. This means that there are areas in which the tumour is “still benign” and in other areas it has already reached malignancy.

Therefore the complete tumour must always be examined under the microscope. Furthermore, all available sources of information must be collected in order to exclude a tumour (examination findings, x-rays and other imaging procedures, fine tissue examination). The following principles apply:

  • Larger tumours close to the body stem or tumours that change on the X-ray image should be completely removed.

If a malignancy is subsequently discovered, the edges of the incision should be removed again with a corresponding safety margin. – Chondrosarcoma occurring on fingers and feet have a rather benign behaviour, even if they show all signs of malignancy under the microscope. Imaging diagnostics: Special tumour diagnostics: Tumour markers have no diagnostic value in the case of chondrosarcoma, as there are no reliable tumour markers to indicate a chondrosarcoma.

Biopsy: If the benign or malignant nature of the tumour cannot be clearly determined, a sample can be taken (biopsy) of the suspect area so that it can be examined in detail. However, it is to be considered that this sampling also causes a so-called scattered metastasis by releasing the tumour from its compound. – X-ray image in two planes of the suspicious area

  • Sonography (ultrasound) of the tumour (provided it is not bone or cartilage)
  • Blood analysis: Blood count BSG (blood cell sedimentation rate) CRP (C-reactive protein) electrolytes (when the bone is attacked, there is an increase in blood calcium) Alkaline phosphatase (aP) and bone-specific aP: in bone-dissolving (osteolytic) processes, prostate specific antigen (PSA) increases: increased in prostate-ca acid phosphatase (sP): increased in prostate-ca uric acid (HRS): increased in case of high cell turnover (very active tumour) Iron: in tumours reduces total protein: in consuming processes reduces protein electrophoresis, immune fixation (special examinations) Urine status: paraproteins – indication of plasmacytoma
  • Blood count
  • BSG (blood cell sedimentation rate)
  • CRP (C-reactive protein)
  • Electrolytes (when the bone is attacked, there is an increase of calcium in the blood)
  • Alkaline phosphatase (aP) and bone-specific aP: increased in bone-dissolving (osteolytic) processes
  • Prostate specific antigen (PSA): elevated in prostate CA Acid phosphatase (sP): elevated in prostate CA
  • Uric acid (HRS): increased with high cell turnover (very active tumour) Iron: decreased with tumours
  • Total protein: lowered in consuming processes
  • Protein electrophoresis, immunofixation (special tests)
  • Urine status: paraproteins – indication of plasmocytoma
  • Blood count
  • BSG (blood cell sedimentation rate)
  • CRP (C-reactive protein)
  • Electrolytes (when the bone is attacked, there is an increase of calcium in the blood)
  • Alkaline phosphatase (aP) and bone-specific aP: increased in bone-dissolving (osteolytic) processes
  • Prostate specific antigen (PSA): elevated in prostate CA Acid phosphatase (sP): elevated in prostate CA
  • Uric acid (HRS): increased with high cell turnover (very active tumour) Iron: decreased with tumours
  • Total protein: lowered in consuming processes
  • Protein electrophoresis, immunofixation (special tests)
  • Urine status: paraproteins – indication of plasmocytoma
  • Local diagnostics (= apparatus-based examination of the local tumour): MRI: With MRI, the spread of the tumour into neighbouring structures such as muscle tissue, nerves and vessels can be clarified.

The use of contract agents can improve the differentiation between benign and malignant tissue. CT: The CT provides special information about the tumor’s bone involvement PET (positron emission tomography): (valence however not yet sufficiently validated)

  • MRI: MRI can be used to clarify the spread of the tumour into neighbouring structures such as muscle tissue, nerves and vessels. The use of contract agents can improve the differentiation between benign and malignant tissue.
  • CT: The CT provides special information about the tumor’s bone involvement
  • PET (Positron Emission Tomography): (valence however not yet sufficiently validated)
  • Locoregional diagnostics (= search for lymph node metastases that rarely occur in chondrosarcoma): Sonography (ultrasound), CT or MRT
  • Sonography (ultrasound)
  • CT if necessary
  • MRI if necessary
  • Extraregional diagnostics: Examination of organs that are particularly frequently affected by chondrosarcoma metastases: -primarily the lungs, liver and adrenal glands. – Examination of organs that are particularly frequently affected by chondrosarcoma metastases: -primarily lungs, liver and adrenal glands. – Systemic diagnostics (= diagnosis of spread and general tumour search): skeletal scintigraphy (3-phase scintigraphy) PET (positron emission tomography; valency not yet sufficiently validated) Special tumour laboratory diagnostics Immunoelectrophoresis: if monoclonal antibodies are detected, indication of plasmacytoma Haemocult test (detection of blood in stool) Tumour markers (e.g.

NSE = neuron-specific enolase in Ewing sarcoma)

  • Skeletal scintigraphy (3-phase scintigraphy)
  • PET (positron emission tomography; valence not yet sufficiently validated)
  • Special tumor laboratory diagnostics
  • Immunoelectrophoresis: if monoclonal antibodies are detected, indication of plasmocytoma
  • Hemoccult test (detection of blood in stool)
  • Tumour markers (e.g. NSE = neuron-specific enolase in Ewing’s sarcoma)
  • MRI: MRI can be used to clarify the spread of the tumour into neighbouring structures such as muscle tissue, nerves and vessels. The use of contract agents can improve the differentiation between benign and malignant tissue. – CT: The CT provides special information about the tumor’s bone involvement
  • PET (Positron Emission Tomography): (valence however not yet sufficiently validated)
  • Sonography (ultrasound)
  • CT if necessary
  • MRI if necessary
  • Examination of organs that are particularly frequently affected by chondrosarcoma metastases: -primarily the lungs, liver and adrenal glands. – Skeletal scintigraphy (3-phase scintigraphy)
  • PET (positron emission tomography; valence not yet sufficiently validated)
  • Special tumor laboratory diagnostics
  • Immunoelectrophoresis: if monoclonal antibodies are detected, indication of plasmocytoma
  • Hemoccult test (detection of blood in stool)
  • Tumour markers (e.g. NSE = neuron-specific enolase in Ewing’s sarcoma)

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  1. Chondrosarcoma
  2. Tumor aftercare