Clinical Practice Status of Sentinel Lymph Node Biopsy for Early-Stage Breast Cancer Patients in China: A Multicenter Study

Figures & data

Table 1 Characteristics of the Patients and Tumors

Characteristic	Number (n,% or Mean (SD))
Number of patients	11,942
Age at diagnosis	51.40 (11.18)
Operative procedure
Lumpectomy	3604 (30.2%)
Mastectomy	7595 (63.6%)
Reconstruction	581 (4.8%)
Unknown	162 (1.4%)
Histology
Ductal carcinoma in situ (DCIS)	1585 (13.3%)
Lobular carcinoma in situ	20 (0.2%)
Invasive ductal carcinoma	8718 (73.0%)
Invasive lobular carcinoma	354 (3.0%)
Other	1103 (9.2%)
Unknown	162 (1.4%)
Molecular subtype
Luminal A	3208 (26.9%)
Luminal B	4203 (35.2%)
Her2-enriched	1333 (11.2%)
Triple-negative	1138 (9.5%)
Unknown	2060 (17.3%)
Tumor size
Tis	1292 (10.8%)
T1	5790 (48.5%)
T2	3213 (26.9%)
T3	145 (1.2%)
T4	23 (0.2%)
Unknown	1479 (12.4%)

Figure 1 The tracer methods used in 11,942 patients to perform SLNB. Dual-tracer refers to a combination of blue dye and radiotracer or fluorescent dye.

Table 2 The Effects of Tracer Method on the Number of Resected SLNs, Metastases Rate of SLNs, and Number of Metastases SLNs

		Tracer Method^a
		A single mapping agent (n=8707)	A combination of blue dye and radiotracer (n=1526)
Number of resected SLNs (n, %)	1–3	3952 (45.4%) 95% CI = 44.3–46.4%	844 (55.3%) 95% CI = 52.8–57.8%
	4–6	3990 (45.8%) 95% CI = 44.8–46.9%	536 (35.1%) 95% CI = 32.7–37.5%
	≧7	765 (8.8%) 95% CI = 8.2–9.4%	146 (9.6%) 95% CI = 8.1–11.0%
Metastases rate of SLNs (%)		1577 (18.1%) 95% CI = 17.3–18.9%	322 (21.1%) 95% CI = 19.1–23.2%
Number of metastases SLNs (median)		1.0	1.0
		Median difference = 0.204 95% CI of the difference = 0.199–0.215

Note: ^aThere are 1709 missing cases in “tracer method”.

Abbreviation: 95% CI, 95% confidence interval.

Table 3 Number of SLN Metastases Classified by Clinical Node States

Clinical Node States*	Number of SLN Metastases, N(%)
	0	1–2	≧3
Clinically node-negative (cN0)	6118 (86.4%) 95% CI = 85.6–87.2%	878 (12.4%) 95% CI = 11.6–13.2%	86 (1.2%) 95% CI = 1.0–1.5%
Clinically node-positive (cN1 or cN2)	448 (49.1%) 95% CI = 45.9–52.4%	392 (43.0%) 95% CI = 39.8–46.2%	72 (7.9%) 95% CI = 6.1 −9.6%

Notes: *3294 patients lacked information of clinical node states. And this table does not include 654 patients who underwent neoadjuvant chemotherapy.

Table 4 The Number of Resected SLNs, The Metastasis Rate of SLNs, and the Number of Metastases SLNs According to Time of Neoadjuvant Chemotherapy (NAC)

	Number of Resected SLNs (Median)	Metastases Rate of SLNs (%)	Number of Metastases SLNs (Median)
Underwent SLNB before NAC	4.0	28.8% (95% CI = 23.0–34.6%)	1.0
Underwent SLNB after NAC	4.0	14.2% (95% CI = 9.5–18.8%)	1.0
Median difference	0.069	/	0.682
95% confidence interval of the difference	0.045–0.091	/	0.563–0.750