Skip to main content

Table 5 Disease-free survival according to the size of the internal mammary lymph node

From: Optimal radiotherapy for patients with internal mammary lymph node metastasis from breast cancer

CharacteristicsIMN size < 1.0 cm (n = 42)IMN size ≥1.0 cm (n = 42)
5-year DFSp-value5-year DFSp-value
Age≤40 years100.0%0.00971.3%0.131
> 40 years77.3% 45.1%
Subtypes1)Non-TNBC96.4%0.03163.5%0.120
TNBC69.2% 47.1%
cT stages1–291.1%0.26765.2%0.119
3–484.2% 44.4%
cN stages2b or 3b89.7%0.11856.4%0.847
3c83.3% 55.6%
Malignant cells on FNABx of the IMN(−) or86.5%0.32754.5%0.930
unknown
(+)
89.7% 58.7%
Extent of IMNSingle ICS90.0%0.89957.0%0.658
Multiple ICS85.9% 56.0%
Neoadjuvant chemotherapyNot performed83.3%0.85240.0%0.417
Performed89.7% 58.5%
EQD2 of the IMN2)50.0–63.5 Gy89.7%0.93233.3%0.019
63.6–70.4 Gy86.4% 69.3%
  1. 1)TNBC was defined as tumors that were negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 on immunohistochemical staining of the breast tumor
  2. 2)Radiotherapy dose was calculated using the EQD2 assuming the α/β ratio of 3.5 Gy
  3. Abbreviations: IMN Internal mammary node, DFS Disease-free survival, TNBC Triple-negative breast cancer, FNABx Fine needle aspiration biopsy, ICS Intercostal space, EQD2 Biologically equivalent dose in 2 Gy fractions