Enneking surgical staging system
The Enneking surgical staging system (also known as the MSTS system) is based on tumor grade, local spread and metastatic disease of malignant musculoskeletal tumors.
It does not classify skull tumors or marrow-originating tumors (e.g. lymphoma, plasmacytoma / multiple myeloma, Ewing sarcoma) 1. It is widely accepted and used by orthopaediac surgeons given its compartment-based classification.
Staging
- stage Ia
- low-grade (G1)
- intracompartmental (T1)
- no metastases (M0)
- stage Ib
- low-grade (G1)
- extracompartmental (T2)
- no metastases (M0)
- stage IIa
- high-grade (G2)
- intracompartmental (T1)
- no metastases (M0)
- stage IIb
- high-grade (G2)
- extracompartmental (T2)
- no metastases (M0)
- stage III
- low or high-grade (G1 or G2)
- intra- or extra-compartmental (T1 or T2)
- distant metastases (M1)
Grading
Low-grade corresponds to Broder grade 1 or 2 (<25% chance metastases) and high-grade corresponds to Broder grade 3 or 4 1.
Related Radiopaedia articles
Bone tumours
The differential diagnosis for bone tumors is dependent on the age of the patient, with a very different set of differentials for the pediatric patient.
-
bone tumors
- bone-forming tumors
- cartilage-forming tumors
- fibrous bone lesions
- bone marrow tumors
- other bone tumors or tumor-like lesions
- adamantinoma
- aneurysmal bone cyst
- benign fibrous histiocytoma
- chordoma
- giant cell tumor of bone
- Gorham massive osteolysis
- hemangioendothelioma
- haemophilic pseudotumor
- intradiploic epidermoid cyst
- intraosseous lipoma
- musculoskeletal angiosarcoma
- musculoskeletal hemangiopericytoma
- primary intraosseous hemangioma
- post-traumatic cystic bone lesion
- simple bone cyst
-
skeletal metastases
- morphology
- location
- impending fracture risk
- staging
- approach
- describing a bone lesion
- differentials