Sentinel lymph node biopsy in clinically detected ductal carcinoma in situ

Table 1 Patient characteristics

Character	NO.	%
Age
Mean	49.7
Range	35-70
Menopausal status
Pre	12	60
Post	8	40
Clinical presentation
Mammographically detected	2	10
Clinically detected	18	90
Palpable mass	15	83.30
Nipple discharge	1	5.50
Paget’s	2	11.10
Multicentricity/mulifocality	5	25
Initial diagnostic tool
FNA	2	10
CNB	18	90
Type of surgery
Lumpectomy	5	25
Simple mastectomy	10	50
Skin sparing mastectomy	5	25
Tumor size
< 3 cm	3	15
> 3 cm < 6 cm	12	60
> 6 cm	5	25
Nuclear grade
Low	0
Intermediate	9	45
High	11	55
Histology
With central necrosis	11	55
Without central necrosis	9	45
Final histology
Pure DCIS	14	70
DCIS + MIC	3	15
DCIS + IDC	3	15
Hormonal receptors
ER+ PR+	6	30
ER- PR-	10	50
Unknown	4	1
Her2/neu
Her2/neu+	9	45
Her2/neu-	4	1
Unknown	7	35
Adjuvant radiotherapy
Yes	5	25
No	15	75

FNA: Fine needle aspiration; CNB: Core needle biopsy; DCIS: Ductal carcinoma in situ; IDC: Invasive ductal carcinoma; MIC: Microinvasion; ER: Estrogen receptor; PR: Progesterone receptor.

Table 2 Accuracy of sentinel lymph node

Accuracy	NO.	%
Total number	20
SLN removed
Range	1-3
Mean	2
SLN positive	2-20	10
Non-SLN positive	0/2	0
SLN visualization rate	20	100
SLN identification rate	20	100
False negative rate	0 out of 18	0

SLN: Sentinel lymph node.

Table 3 Pathology of sentinel lymph node and non-sentinel lymph node

Final diagnosis	n	%	SLN positive		Non-SLN positive
			n	%	n	%
Pure DCIS	14	70	1/14	7.1	None	0
DCIS/MIC	3	15	0/3	0
DCIS/IDC	3	15	1/3	33.3	None	0
Total	20		2/20	10	0/2	0

DCIS: Ductal carcinoma in situ; MIC: Microinvasion; IDC: Invasive ductal carcinoma; SLN: Sentinel lymph node.

Table 4 Comparison between initial and final pathology “underestimation rate”n (%)

Initial diagnosis	Final diagnosis	Underestimation rate
		NO.	%
Pure DCIS	Pure DCIS 14 (70)
	DCIS/MIC 3 (15)	6/18	33%
	DCIS/IDC 3 (15)

DCIS: Ductal carcinoma in situ; MIC: Microinvasion; IDC: Invasive ductal carcinoma.