Radiation Oncology/Breast/Staging

From Wikibooks, open books for an open world
Jump to: navigation, search

Front Page: Radiation Oncology | RTOG Trials

Breast: Main Page | Staging | Breast Overview | Prevention | Benign | DCIS | LCIS | Paget's | Phyllodes tumor | Early stage | Advanced stage | Post mastectomy | Inflammatory | Partial breast irradiation | Regional lymphatics | Hormonal therapy | Chemotherapy | RT technique | Recurrence | Toxicity of RT | Randomized | NSABP trials

Current staging[edit]

AJCC 7th Edition (2009)
Primary Tumor:

  • T0 - no primary tumor found
  • Tis - in situ (DCIS or LCIS or Paget's)
  • T1 ≤ 2 cm
    • T1mi ≤ 0.1 cm (microinvasive)
    • T1a > 0.1 to 0.5 cm
    • T1b > 0.5 to 1 cm
    • T1c > 1 to 2 cm
  • T2 > 2 to 5 cm
  • T3 > 5 cm
  • T4 Chest wall /skin
    • T4a Chest wall (not including pectoralis muscle)
    • T4b Skin edema (peau d'orange), ulceration, or satellite skin nodules
    • T4c Both 4a and 4b
    • T4d Inflammatory carcinoma
Regional Lymph Nodes
Clinical staging Pathologic staging
cN0 No lymph node metastases pN0 No lymph node metastases
cN1 Movable ipsilateral axillary lymph nodes pN1mi Micrometastases (> 0.2mm but <= 2.0 mm)
    pN1a 1-3 axillary lymph nodes (at least 1 > 2.0mm)
    pN1b Metastases in IM nodes (micrometastases, or macrometastases detected by SLN biopsy but not clinically detected)
    pN1c 1-3 axillary lymph nodes and metastases in IM nodes (micrometastases, or macromets detected by SLN but not clinically detected)
cN2a Ipsilateral axillary lymph nodes fixed or matted pN2a 4-9 axillary lymph nodes (at least 1 > 2.0 mm)
cN2b Clinically detected internal mammary nodes in the absence of axillary lymph node metastases pN2b Metastases in clinically detected IM nodes in the absence of axillary lymph nodes
cN3a Infraclavicular lymph nodes (level III) pN3a 10 or more axillary lymph nodes (at least 1 > 2.0 mm); or infraclavicular (level III) lymph nodes
cN3b Clinically apparent internal mammary nodes with axillary lymph node involvement pN3b Metastases in clinically detected IM nodes in the presence of positive axillary nodes; or microscopic IM nodes and more than 3 axillary lymph nodes
cN3c Supraclavicular lymph nodes pN3c Supraclavicular lymph nodes

Mnemonics: "A" Nodes are "A"xillary, "B" Nodes are internal "B"reast (eg IMNs), "C" Nodes are supra"C"lavicular - excludes N1 subgroups

Distant Metastases:

  • M0 - none
  • cM0(i+) - no clinical or radiographic evidence of distant metastases, but tumor cells detected in circulating blood, bone marrow, or other tissues (e.g. prophylactically removed ovaries), ≤ 0.2 mm, in a patient without symptoms or signs of metastases.
  • M1 - distant detectable metastases; or histologically proven > 0.2 mm

Stage Grouping:

  • 0: Tis
  • IA: T1 N0
  • IB: T0-T1 N1mi
  • IIA: T0-1 N1 or T2 N0
  • IIB: T2 N1 or T3 N0
  • IIIA: T3 N1 or T0-3 N2
  • IIIB: T4 N0-2
  • IIIC: N3
  • IV: M1

Changes from 6th edition:

  • T1mic changed to T1mi to indicate microscopic disease
  • Clarification of wording of "not clinically detected" and "clinically detected" internal mammary nodes. *Clarification of Isolated tumor cells (ITC).
  • Subdivision of Stage I into IA and IB (IB includes T0-T1 with N1mi nodal micrometastases). Otherwise, no changes in TNM or Overall Stage
  • New cM0(i+) category for circulating tumor cells or incidentally discovered metastatic cells in other tissue
  • Clarification of assigning staging after neoadjuvant therapy (yc or ypTNM)


Older staging versions[edit]

AJCC 6th edition (2002)
Primary Tumor:

  • T0 - no primary tumor found
  • Tis - in situ (DCIS or LCIS or Paget's)
  • T1 ≤ 2 cm
    • T1mic ≤ 0.1 cm (microinvasive)
    • T1a > 0.1 to 0.5 cm
    • T1b > 0.5 to 1 cm
    • T1c > 1 to 2 cm
  • T2 > 2 to 5 cm
  • T3 > 5 cm
  • T4 Chest wall /skin
    • T4a Chest wall (not including pectoralis muscle)
    • T4b Skin edema (peau d'orange), ulceration, or satellite skin nodules
    • T4c Both 4a and 4b
    • T4d Inflammatory carcinoma
Lymph nodes
Clinical staging Pathologic staging
cN0 No lymph node metastases pN0 No lymph node metastases
cN1 Movable ipsilateral axillary lymph nodes pN1mi Micrometastases (> 0.2mm but <= 2.0 mm)
    pN1a 1-3 axillary lymph nodes
    pN1b Microscopic involvement of IM nodes (not clinically apparent) but no axillary nodes
    pN1c 1-3 axillary lymph nodes and microscopic involvement of IM nodes
cN2a Ipsilateral axillary lymph nodes fixed or matted pN2a 4-9 axillary lymph nodes
cN2b Clinically apparent internal mammary nodes in the absence of axillary lymph node metastases pN2b Clinically apparent IM nodes in the absence of axillary lymph nodes
cN3a Infraclavicular lymph nodes pN3a 10 or more axillary lymph nodes; or infraclavicular lymph nodes
cN3b Clinically apparent internal mammary nodes with axillary lymph node involvement pN3b Clinically apparent IM nodes in the presence of positive axillary nodes; or microscopic IM nodes and more than 3 axillary lymph nodes
cN3c Supraclavicular lymph nodes pN3c Supraclavicular lymph nodes

Mnemonics: "A" Nodes are "A"xillary, "B" Nodes are internal "B"reast (eg IMNs), "C" Nodes are supra"C"lavicular - excludes N1 subgroups

Nodes:

  • Isolated tumor cells (ITC) - small clusters of cells <= 0.2 mm, usually with no histologic evidence of malignant activity (such as proliferation or stromal reaction). Designated pN0. If IHC or PCR is performed, may be designated pN0(i+),pN0(i-),pN0(mol+),or pN0(mol-).
  • Micrometastases (pN1mi) - > 0.2mm but <= 2.0 mm. May also be designated pN1mi(i+) or pN1mi(i-) if IHC is performed.

Distant metastasis:

  • M0 No
  • M1 Yes

Stage grouping:

  • Stage 0: Tis
  • Stage I: T1,N0,M0
  • Stage IIA: T0-1,N1,M0 or T2,N0,M0
  • Stage IIB: T2,N1,M0 or T3,N0,M0
  • Stage IIIA: T3,N1,M0 or T0-3,N2,M0
  • Stage IIIB: T4,any N,M0
  • Stage IIIC: any T,N3,M0
  • Stage IV: any T,any N,M1


AJCC 5th Edition (1997)

  • pN1a - micrometastases (<0.2 cm)
  • pN1bi - 1-3 nodes, < 2 cm
  • pN1bii - 4+ nodes, < 2 cm
  • pN1biii - extracapsular extension, < 2 cm
  • pN1biv - > 2 cm

Otherwise unchanged compared to 6th edition

New Classifications[edit]

For additional information, see Tissue microarrays (Breast/Breast overview)

Gene expression profiling is the basis for additional classification schemes.

  • Luminal A type - ER+ and/or PR+, HER2–. Usually low grade. These express genes similar to normal cells lining breast ducts and glands
  • Luminal B type - ER+ and/or PR+, HER2+. These are similar to luminal A, but grow faster and have a slightly poorer prognosis.
  • Basal type - ER–, PR–, HER2–, cytokeratin 5/6 positive, and/or HER1+. Also known as "triple negative". Higher prevalence in young African American women.
  • HER2 type - ER-, PR-, HER2+. Usually high histological grade.