Mesenchymal Chondrosarcoma - Causes, Symptoms, Diagnosis, And Treatment

Introduction:

Sarcoma is a broad term used to describe cancers that originate from the bones and soft tissues of the body. Soft tissues include muscles, fat, nerves, blood vessels, cartilages, ligaments, etc. So far, more than 70 types of sarcomas have been identified. The symptoms, diagnosis, and treatment depend on the type of cancer in question. Read this article to know more about the causes, symptoms, diagnosis, and treatment of mesenchymal chondrosarcoma, a rare soft tissue tumor.

What Is Mesenchymal Chondrosarcoma?

It is essential to understand the terms “mesenchymal” and “chondrosarcoma”.

Mesenchymal: A type of animal tissue composed of immature bone, fat, muscles, nerves, and cartilage cells.

Chondrosarcoma: A rare type of cancer that originates from bones or cartilage (a flexible and supportive tissue found throughout the body).

About Mesenchymal Chondrosarcoma:

Mesenchymal chondrosarcoma is an aggressive yet extremely rare type of cancer compared to the conventional chondrosarcoma. Conventional chondrosarcoma is a bone cancer that originates from cells of the cartilage. The body’s skeletal network is initially made of cartilage and then converted to bone. The cartilage tissue is a soft tissue that acts as a cushion for the skeleton. Most mesenchymal chondrosarcomas develop from the rib, spine, and jawbones. One-third of the cases originate from non-skeletal structures such as the muscles and fat. Mesenchymal chondrosarcoma often occurs in young adults and invades distant organs (metastasis).

Most Common Sites Affected by Mesenchymal Chondrosarcoma:

Mesenchymal chondrosarcomas are malignant neoplasms that typically affect the cartilage. They have diverse morphology and usually initiate in the long bones or the pelvis. The most common sites of mesenchymal chondrosarcoma involvement are the axial skeleton's bones, including the scapula, sternum, ribs, and pelvis. The acetabulum is a more specific site affected by mesenchymal chondrosarcoma in the pelvis. It can also affect the proximal femur and humerus. The extraskeletal areas commonly affected by mesenchymal chondrosarcoma include the central nervous system, lower extremities, and orbits.

What Causes Mesenchymal Chondrosarcoma?

• Like all cancers, the pathogenesis behind mesenchymal chondrosarcoma has not been identified so far. The risk factors that prompt the development of this cancer are yet to be identified.

• Generally, cancer development is influenced by mutations in the genes that control cell growth and division. These genes are known as tumor suppressor genes or oncogenes. An abnormality in these genes results in uncontrolled cell growth, forming a mass.

• Abnormalities in the DNA (deoxyribonucleic acid) that carry the cell cycle code play a vital role in the cancerous transformation of cells.

• The deletion of a part of chromosome 8 is the characteristic genetic change that occurs in mesenchymal chondrosarcoma.

• The new sequence in the broken gene bonds with other genes to form a new code inconsistent with the cell cycle.

• The genes have been identified and termed HEY1 and NCOA2.

What Are the Signs and Symptoms of Mesenchymal Chondrosarcoma?

Depending on the location and aggressiveness of the tumor, the symptoms vary.

The general symptoms include:

1. Pain and swelling in the affected area.

2. The symptoms can be present before the diagnosis is made for a long time.

3. If cancer is large enough to compress nerves, neurological symptoms might become evident.

4. Mesenchymal chondrosarcoma compressing the spinal cord can lead to paralysis.

5. Tumor of the orbit or eyeball can cause visual disturbances, pain, swelling, and protrusion of the eyeball.

6. If the tumor is too aggressive, it can spread to other body parts such as the lungs, lymph nodes, and bones. Metastasis can cause life-threatening complications.

Who Is Affected by Mesenchymal Chondrosarcoma?

• Mesenchymal chondrosarcoma is so rare that only 800 cases have been reported.

• Young adults and children (10 to 30 years) are commonly affected, but these tumors occur in older adults.

• Mesenchymal chondrosarcoma has a female predilection.

• Around 5% to 10% of chondrosarcomas account for mesenchymal chondrosarcoma.

How Is Mesenchymal Chondrosarcoma Diagnosed?

• Clinical Examination: The doctor will look for signs of the tumor such as abnormal mass, neurological disturbances, etc. A thorough medical, personal, and habitual history of the patient is analyzed.

• Biopsy: It is considered the gold standard for confirming the diagnosis of any tumor. A sample of the tumor is taken and microscopically analyzed. Abnormalities in the cell structure and division can be determined after a biopsy. The biopsy can be either needle-guided or open.

• Imaging Modalities: Advanced imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) aid in the visualization of the tumor. It can help determine the extent and boundaries of the tumor. Visualizing the tumor also helps in planning the surgery. Additionally, a CT scan of the lungs is beneficial in confirming lung metastasis.

• Bone Scans and X-rays: If the tumor has spread to the bones, there can be changes in the bone structure and bone activity. These changes can be visualized through X-rays and bone scans.

How Is Mesenchymal Chondrosarcoma Treated?

The treatment of mesenchymal chondrosarcoma involves a multidisciplinary approach. Health professionals such as pediatric or medical oncologists, radiologists, and surgeons play a key role in the treatment. Factors that determine the treatment modality include location, extent, size, metastasis, and tumor stage. Patient factors such as age, systemic conditions, and overall health are to be considered. The benefits and risks of the treatment should be assessed priorly to minimize mortality and morbidity.

1. Surgery: It is the first line of treatment if the tumor is of considerable size. Surgery can be performed before or after the chemotherapy.

2. Chemotherapy: The use of certain drugs called chemotherapeutic agents aid in controlling the growth and division of cancer cells. These drugs target cancer cells by interfering with their cell cycle.

3. Radiation Therapy: For larger tumors, radiation therapy is given after surgical excision to prevent recurrence and increase the quality of life. However, most clinicians prefer chemotherapy over radiation therapy as their treatment of choice.

Prognosis and Survival Rate:

• According to studies, a person's overall mortality rate was 55 %, 43.5 %, and 15.7 % at 5, 10, and 20 years of age, respectively.

• In patients receiving chemotherapy, overall survival rates are 84% and 80%, respectively, within five and ten years.

• The survival rates of five year and ten year survivors without chemotherapy in surveillance are 73% and 46%, respectively.

Conclusion:

Mesenchymal chondrosarcoma is an aggressive yet extremely rare type of cancer originating from bones or cartilage (a supportive tissue found in the body). The symptoms of this cancer include pain, swelling, and neurological changes. The diagnosis can be confirmed after a physical examination, biopsy, and advanced imaging. Surgery and chemotherapy are the preferred treatment modalities. Even after the treatment, it is necessary to follow up with the patients to ensure no cancer recurrence. Overall, mesenchymal chondrosarcoma has a satisfactory prognosis.