Soft-tissue sarcoma

World Health Organization (WHO) classification of tumours[10]World Health Organization. WHO classification of tumours: soft tissue and bone tumours. 5th ed (Vol 3). Lyon, France: IARC Press; 2020.

The TNM Classification of Malignant Tumours is of limited value because nodal spread is rare outside Ewing's sarcoma, epithelioid sarcoma, synovial sarcoma, angiosarcoma, clear cell sarcoma, and rhabdomyosarcoma. Tumours are staged on size (5 cm or less, >5 cm), location (superficial or deep to deep fascia), and whether or not they are metastatic. In rare circumstances, nodal spread may be included. Histopathological grade is an important factor in determining outcome.

The WHO classification of tumours describes 4 stages.

Stage IA

• Primary tumour 5 cm or less in greatest dimension

• Regional lymph nodes cannot be assessed or no regional lymph node metastasis

• No distant metastasis

• Low grade

Stage IB

• Primary tumour >5 cm in greatest dimension

• Regional lymph nodes cannot be assessed or no regional lymph node metastasis

• No distant metastasis

• Low grade

Stage IIA

• Primary tumour 5 cm or less in greatest dimension

• Regional lymph nodes cannot be assessed or no regional lymph node metastasis

• No distant metastasis

• High grade

Stage IIB

• Superficial primary tumour >5 cm in greatest dimension

• Regional lymph nodes cannot be assessed or no regional lymph node metastasis

• No distant metastasis

• High grade

Stage III

• Deep primary tumour >5 cm in greatest dimension

• Regional lymph nodes cannot be assessed or no regional lymph node metastasis

• No distant metastasis

• High grade

Stage IV

• Any primary tumour size and depth

• Regional lymph node metastasis and no distant metastasis or any regional lymph node involvement and distant metastasis

• Any grade

American Joint Committee on Cancer TNM staging system (8th edition)[52]Amin MB, Edge S, Greene F, et al. (eds); American Joint Committee on Cancer. AJCC cancer staging manual. 8th ed. New York, NY: Springer; 2017.

The American Joint Committee on Cancer staging system describes the extent of disease based on the following anatomical factors: size and extent of the primary tumour (T); regional lymph node involvement (N); and presence or absence of distant metastases (M). Non-anatomical prognostic factors (e.g., tumour grade, biomarkers) may be used to supplement the staging of certain cancers.