Soft Tissue Sarcoma and its Management

Of note, gastrointestinal stromal tumours (GIST) (sarcomas originating in the GI tract) are unresponsive to current chemotherapies, but respond to imatinib [Demetri 2002] and sunitinib, which are tyrosine kinase inhibitors. Therefore, GIST is no longer included in current STS chemotherapy studies and will no longer be part of this discussion.

Several staging systems [e.g. the American Joint Committee on Cancer 2002 (AJCC) and International Union against Cancer (UICC) staging systems] have been devised for STS to help determine the prognosis for individual patients. The stage of disease is determined based on the histopathological grade, and depth and size of the tumour (Table 2). Stage I tumours are low grade (i.e. not aggressive), small and superficial or deep but with no metastases; patients with stage I disease have a good prognosis – 5-year survival rates are approximately 90% [Stojadinovic 2002]. In contrast, high grade, deep and/or bulky tumours are associated with a 5-year survival of only 10–20% [Stojadinovic 2002].

Management of STS depends on the stage of disease and histological subtype [Clark 2005]. Surgery is the standard treatment for all patients with adult-type localized soft tissue sarcomas. While radiation therapy as an adjuvant to surgery is a standard for intermediate-high grade deep tumours with a diameter of >5 cm, it is an option in selected cases of deep lesions >5 cm or low-grade tumours. Radiation therapy should be administered post-operatively. Adjuvant chemotherapy might improve, or at least delay, distant and local recurrence in high-risk patients. A recently reported meta-analysis found a limited benefit in survival. However, studies are conflicting, and a final demonstration of efficacy is lacking. Therefore, adjuvant chemotherapy is not standard treatment in adult-type soft tissue sarcomas, and can be proposed as an option to the high-risk individual patient (having a G2–3, deep, >5 cm tumour) [Casali 2009].

Table 2. AJCC staging for soft tissue sarcoma tumours.

Stage Definition  

Stage I

Low-grade, superficial or deep, no metastases

  • Tumour grade: well differentiated or moderately   differentiated
  • Tumour size: ≤ 5 cm and superficial or deep, or >5 cm
    and superficial or deep
  • No metastases

Stage II

High-grade, superficial or deep, no metastases

  • Tumour grade: poorly differentiated or undifferentiated
  • Tumour size ≤5 cm and superficial or deep, or >5 cm
    and superficial
  • No metastases

Stage III

High-grade, large and deep, no metastases

  • Tumour grade: poorly differentiated or undifferentiated
  • Tumour size: >5 cm and deep
  • No metastases

Stage IV

Any metastases to lymph nodes or distant sites

  • Any tumour grade
  • Any tumour size
  • Metastases to lymph nodes or distant sites

American Joint Committe on Cancer 2002