Enneking staging system
Stage Grade Site Metastases
I A Low Intra None B Low Extra None
II A High Intra None B High Extra None
Notes:
The Enneking system of staging is similar to the TNM system except that sarcomata do not metastasize to the lymph nodes, so these are ignored in the system.
Stage 1 is a low grade tumor, 2 is high grade and 3 is where a met. is present
Site is whether the tumor is in one compartment or more. E.g. an Osteosarcoma in the popliteal fossa is in more than one compartment.
If one or more metastasis is present the tumor is classified as a Grade 3.
Osteosarcoma is usually grade 2b or 3 when first seen.