Staging - not myeloma

Author: Nat Pernick, M.D. (see Authors page)

Revised: 22 November 2016, last major update June 2005

Copyright: (c) 2003-2016,, Inc.

PubMed search: staging [title] "bone" NOT myeloma NOT lymphoma

Table of Contents
Definition / general
Cite this page: Staging - not myeloma. website. Accessed December 15th, 2018.
Definition / general
  • Classification excludes lymphoma and myeloma
  • AJCC 7th edition: changes from AJCC 6th are in Stage III, which must be G3 or G4

  • Primary tumor (pT)
    • TX: Primary tumor cannot be assessed
    • T0: No evidence of primary tumor
    • T1: Tumor 8 cm or less in greatest dimension
    • T2: Tumor more than 8 cm in greatest dimension
    • T3: Discontinuous tumors in the primary bone site

  • Regional lymph nodes (pN)
    • NX: Regional lymph nodes cannot be assessed
    • N0: No regional lymph node metastasis
    • N1: Regional lymph node metastasis
      • Note: because of the rarity of lymph node involvement in bone sarcomas, the designation NX may not be appropriate, and cases should be considered N0 unless clinical node involvement is clearly evident

  • Distant metastasis (pM)
    • M0: No distant metastasis
    • M1: Distant metastasis
    • M1a: Lung
    • M1b: Other distant sites

  • Stage grouping
    • IA: T1 N0 M0, well to moderately differentiated / low grade (G1, G2, GX)
    • IB: T2-3 N0 M0, well to moderately differentiated / low grade (G1, G2, GX)
    • IIA: T1 N0 M0, poorly differentiated/undifferentiated / high grade (G3, G4)
    • IIB: T2 N0 M0, poorly differentiated/undifferentiated / high grade (G3, G4)
    • III: T3 N0 M0, G3, G4
    • IVA: Any T N0 M1a, any grade
    • IVB: Any T N1 Any M, any grade or Any T Any N M1b any grade

  • Enneking staging
    • Uses histologic grade and anatomic location of tumor
    • Grade: well differentiated / low grade (tumor cells resemble cells from which they are thought to arise); poorly differentiated / high grade (can barely recognize what normal counterpart of tumor cell would be); also graded as 1 - 4 (1 - 2: low grade, 3 - 4: high grade)
    • Anatomic location: one compartment (confined to bone) or two compartments (tumor has broken through bone into soft tissue)
    • Staging same as TNM except that T1 means one compartment and T2 means 2 or more compartments; stage IIIA is any grade and T1 M1 and stage IIIB is any grade and T2 M1

  • Margins
    • Intralesional margin: microscopic evidence of lesion at margin after debulking or curetting
    • Marginal margin: lesion is shelled out, usually within a pseudocapsule; no normal tissue is removed
    • Wide margin: tumor with pseudocapsule, reactive zone and cuff of normal tissue is removed
    • Radical margin: entire compartment with tumor is removed (does not refer necessarily to the surgery, but the tumor location and tissue removed)