Radiation Oncology/Sarcoma/Staging

Sarcoma Staging

AJCC 7th Edition (2009) Primary Tumor:
 * T1 - less than or equal to 5cm
 * T1a - superficial
 * T1b - deep
 * T2 - greater than 5cm
 * T2a - superficial
 * T2b - deep

Regional Lymph Nodes:
 * N0 - no
 * N1 - yes

Distant Metastases:
 * M0 - none
 * M1 - yes

Grade:
 * AJCC now recommends a three-tier system. The FNCLCC (French) system is the preferred grading system.
 * The grade is determined by three parameters:
 * Differentiation
 * Mitotic activity
 * Extent of necrosis

Stage Grouping:
 * IA - T1a/b N0 G1 - low grade (grade 1), small
 * IB - T2a/b N0 G1 - low grade (grade 1), large
 * IIA - T1a/b N0 G2-3 - mod/high grade (grade 2-3), small
 * IIB - T2a/b N0 G2 - mod grade (grade 2), large
 * III - T2a/b G3, or N1 - high grade (grade 3), large; or node positive
 * IV - M1 - metastatic

Changes from AJCC 6th Edition:
 * Now incorporates a three-tiered grading system. For staging, there is now a distinction between G2 and G3, at least for tumors >5 cm.
 * N1 is now Stage III instead of Stage IV
 * Stage I is divided into IA and IB. Stage II is divided into IIA and IIB.
 * Deep or superficial location of tumor no longer is a factor in overall stage

Notes:
 * This staging system does not apply to Kaposi's sarcoma, GIST (is now staged with its own classification), fibromatosis (desmoid tumor), and infantile fibrosarcoma; does not apply to sarcomas arising in the dura mater or brain, parenchymal organs, and hollow viscera.
 * Now includes dermatofibrosarcoma protuberans (which was previously excluded), angiosarcoma, and extraskeletal Ewing's sarcoma
 * Superficial - located entirely in the subcutaneous tissues without any degree of any involvement of the muscular fascia or underlying muscle

Older systems
AJCC 6th Edition (2002)
 * T1 - less than or equal to 5cm
 * T1a - superficial
 * T1b - deep
 * T2 - greater than 5cm
 * T2a - superficial
 * T2b - deep

Stage Grouping:
 * Stage I - All low grade, N0, M0
 * Stage II - T1a/b-T2a, N0, high grade
 * Stage III - T2b, N0, high grade
 * Stage IV - N1 or M1, any grade

Note:
 * Excludes dermatofibrosarcoma protuberans. Also excludes Kaposi's, fibromatosis (desmoid tumor), sarcoma arising from dura mater, brain, parenchymal organs, and hollow viscera.

AJCC 5th Edition (1997)
 * Stage IA - low grade, small
 * Stage IB - low grade, large and superficial
 * Stage IIA - low grade, large and deep
 * Stage IIB - high grade, small and deep
 * Stage IIC - high grade, large, superficial
 * Stage III - high grade, large, deep
 * Stage IV - positive nodes or distant mets

AJCC 1st edition (1975-77)
 * T3 is bone, major nerve, or vessel involvement
 * Stage I - all grade 1
 * Stage II - all grade 2
 * Stage III - all grade 3, or T3