Radiation Oncology/Sarcoma/Fibrosarcoma


Benign Fibrous HistologiesEdit

  • Nodular fasciitis: rapid growth over several weeks, pain, tenderness. Plump mature fibroblasts. Self-limiting process; recurrence uncommon after excision
  • Fibroma: nonspecific term. Dense fibrous nodule. Simple excision
  • Elastofibroma: rare, slow-growing benign tumor. Typically lower portion of the scapula. Repetitive manual tasks. Considered reactive lesions. Swollen eosinophilic collagen and elastic fibers. Simple excision
  • Superficial fibromatosis: arise from fascia or aponeuroses, small and slow growing
  • Deep fibromatosis: clinically diverse, deep-seated fibrous neoplasms

Fibrosarcoma EpidemiologyEdit

  • 2-6% of primary malignant bone lesions
  • Arise most commonly in tubular long bones, usually femur or tibia
  • Most patients are 30-70; equal men and women
  • Predisposing factors (~30% cases) include Paget's, fibrous dysplasia, osteomyelitis, bone infarcts, bone cysts, benign giant cell tumors, desmoplastic fibromas, or previous RT treatment

Natural HistoryEdit

  • Locally aggressive
  • Metastatic potential related to grade
    • High grade similar to osteosarcoma: 5-year OS ~25%
    • Low grade: 5-year (and 10-year) OS ~50%. Mets rate 5-15%
  • Survival: 5-year 34%, 10-year 28%, 20-year 25%
  • Children have relatively milder prognosis


  • Lytic with no reactive sclerosis
  • High grade lesions show cortical destruction and periosteal reaction; sometimes with soft-tissue mass
  • Radiographically very similar to osteosarcoma


Treatment OverviewEdit

  • Aggressive surgical resection
  • Not considered highly radiosensitive, but RT recommended for inoperable tumors, residual disease, and palliation
  • Perez (4th ed) recommends doses 66-70Gy with shrinking-field technique