Sarcoma

What Is Sarcoma?

Sarcomas are solid tumors arising from mesenchymal tissues (bone, muscle, fat, blood vessels, connective tissue). They differ from carcinomas (which arise from epithelial tissues like skin or organ linings).

Key fact: Sarcomas account for less than 1% of all cancers but are common in children. Many sarcomas are chemotherapy-responsive and curable with multimodal treatment.

Types

• Soft tissue sarcomas: Leiomyosarcoma, liposarcoma, fibrosarcoma, synovial sarcoma. Can occur anywhere soft tissue exists.
• Bone sarcomas: Osteosarcoma (most common), Ewing sarcoma (usually in adolescents/young adults). Arise in bone.
• Other types: Rhabdomyosarcoma (children), angiosarcoma, desmoid tumors.

Risk Factors

• Age: Osteosarcoma and Ewing sarcoma typically occur in ages 10-25. Soft tissue sarcomas increase with age.
• Genetic syndromes: Li-Fraumeni syndrome, neurofibromatosis, familial adenomatous polyposis (FAP).
• Prior radiation: Can develop years after radiation therapy for another cancer.
• Lymphedema: Angiosarcoma can develop in chronically swollen arms.

Symptoms

• Mass or swelling (soft tissue or bone)
• Pain (especially bone sarcomas)
• Functional impairment if near joints
• Pathological fracture (bone breaks easily)
• For Ewing sarcoma: fever, fatigue

Important: Any mass that persists for more than 2 weeks warrants evaluation.

Diagnosis

Diagnostic approach:

• Imaging: MRI (soft tissue) or X-ray/CT (bone) to assess location and size.
• Biopsy: Core needle or incisional biopsy for pathology. Biopsy approach matters for surgical planning.
• Staging: CT chest (check for lung metastases, common site for sarcoma spread).
• Molecular testing: Specific translocations (e.g., EWSR1 in Ewing sarcoma) aid diagnosis and prognosis.

Staging & Grade

Sarcomas use TNM staging. Grade (histological grade) is critical for prognosis:

• Low-grade: Slower growing, lower metastatic risk.
• High-grade: Aggressive, higher metastatic risk. Most require chemotherapy.

Treatment Options

Surgery (Limb-Sparing)

Complete surgical resection with adequate margins is critical. Modern limb-sparing surgery allows removal of tumor while preserving function, often without amputation.

Chemotherapy

For high-grade sarcomas, especially bone sarcomas (osteosarcoma, Ewing). Neoadjuvant chemo shrinks tumor before surgery; adjuvant chemo treats micrometastases. Standard regimens vary by sarcoma type.

Radiation Therapy

Used if surgery cannot achieve adequate margins, or for unresectable disease. Can be primary treatment for some soft tissue sarcomas.

Targeted Therapy & Immunotherapy

Emerging options based on molecular characteristics. Increasingly used in advanced disease or when standard treatments fail.

Prognosis

Depends on size, grade, location, and type:

• Low-grade: Often excellent prognosis with surgery alone; 5-year survival 80-90%+.
• High-grade localized: With chemotherapy and surgery, 5-year survival 60-80%.
• Osteosarcoma/Ewing: With multimodal therapy, 70-80% 5-year survival for localized disease.
• Metastatic: More guarded prognosis, but many remain long-term survivors with aggressive treatment.

Key Questions for Your Doctor

• What type and grade of sarcoma do I have?
• Is my tumor localized or metastatic?
• Can limb-sparing surgery be done?
• Do I need chemotherapy? For how long?
• What are functional outcomes after treatment?
• Are there genetic implications for family members?