Soft Tissue Sarcoma

• • Soft-tissue sarcomas present as asymptomatic large masses in the extremities or retroperitoneum but may also develop occasionally in the neck or within the abdominal viscera

  • Originate from a wide variety of mesenchymal cell types and include:

  • -Liposarcoma

    -Fibrosarcoma

    -Rhabdomyosarcoma

    -Leiomyosarcoma

    -Desmoid tumors

  • Tumor grade rather than the cell of origin determines natural history

  • Most soft-tissue sarcomas arise de novo; rarely result from malignant degeneration of a benign lesion

  • Sarcomas generally metastasize via a hematogenous route, most commonly to the lung

  • Most important prognostic factors include tumor size and grade

Epidemiology

• • Account for 1% of all new cancer diagnoses

  • 50% of soft-tissue sarcomas arise in the lower extremities, most commonly in the thigh

  • There are familial syndromes that genetically predispose patients to the formation of soft-tissue sarcomas:

  • -Gardner syndrome: Desmoid tumors

    -Recklinghausen disease: Neurofibrosarcomas

    -Li Fraumeni syndrome

  • Risk factors include:

  • -Irradiation

    -Chronic extremity lymphedema

Symptoms and Signs

• • Asymptomatic large soft-tissue mass

  • Nerve compression/invasion may result in pain, parasthesias, or neuropathy

  • Venous compression/invasion may result in deep venous thrombosis (DVT) formation

Imaging Findings

• • Chest x-ray: May demonstrate evidence of metastases

  • CT scan: Demonstrates a homogenous soft-tissue density mass and differentiate between hematoma or abscess

  • MRI

  • -Accurately defines the extent of the sarcoma and invasion of surrounding structures

    -Probably the best imaging test in the evaluation of an extremity sarcoma

• • Soft-tissue sarcoma

  • Traumatic injury

  • Hematoma

  • Cutaneous neoplasm/metastasis

  • Desmoid tumor

  • Subcutaneous or intramuscular lipoma

  • Abscess

Rule Out

• • Other cutaneous malignancy or metastasis

  • Hematoma

  • Abscess

• • Thorough history and physical exam

  • Core needle or incisional biopsy to establish diagnosis

  • CT or MRI (preferred) to define extent of tumor and invasion of surrounding structures

  • Chest x-ray or CT to evaluate for evidence of pulmonary metastases

When to Admit

• • Extremity sarcoma work-up can be performed as an outpatient

When to Refer

• • A multidisciplinary approach is essential to ensure optimal outcomes, including an oncology surgeon, medical oncology, and radiation-oncology

• • Establish diagnosis histologically with a core needle biopsy or incisional biopsy

  • Radiographically define extent of tumor and invasion of surrounding structures

  • Evaluate for pulmonary metastases

  • Surgical wide local excision with a 2 cm margin

  • Postoperative radiation therapy for all high-grade sarcomas and those > 2 cm

  • Sometimes adjuvant chemotherapy

  • Preoperative radiation therapy for patients with tumors larger than 10 cm or to facilitate limb-sparing procedures

Surgery

Indications

• • Initial incisional biopsy to establish diagnosis (always orientate extremity incision longitudinally)

  • Therapeutic wide local excision, ideally with 2 cm margin vs ...