Viale et al identified risk factors associated with metastasis to axillary sentinel lymph nodes in patients with breast cancer. These can help stratify patients based on the risk of nodal metastasis. The authors are from the Universities of Milan and Bari in Italy.
Factors associated with an increase risk of sentinel nodal metastasis:
(1) tumor size (> 2 cm most, <= 0.5 cm least)
(2) multifocal breast involvement
(3) peritumoral vascular invasion (PVI)
Factors associated with a decreased risk of sentinel nodal metastasis:
(1) favorable histology (medullary, cribriform, tubular or mucinous)
(2) negative progesterone receptor status
Features |
Tumor Diameter < 1 cm |
Tumor Diameter 1 - 2 cm |
Tumor Diameter > 2 cm |
PVI negative favorable histology |
10% |
16% |
12% |
PVI negative ductal or lobular unifocal |
15% |
26% |
38% |
PVI negative ductal or lobular multifocal |
18% |
38% |
62% |
PVI positive |
57% |
66% |
77% |
after Table 4, page 497
where:
• A low risk group is 10-18%, moderate risk 26-38% and high risk 57-77%.
• I could not find how tumor size was handled with multifocal tumors. One option is the size of the largest tumor. The second is somehow combining dimensions of each focus; simple addition of diameters would be inadequate.
Specialty: Hematology Oncology, Surgery, general, Obstetrics & Gynecology