Altered lymphatic drainage patterns in re-operative sentinel lymph node biopsy for ipsilateral breast tumor recurrence

Table 6 Lymphatic drainage patterns according to previous radiotherapy

a) non-AX group^a
	Without RT^c	With RT
	N = 54	N = 27	P value
Visualization on lymphoscintigraphy
Yes	52 (96.3%)	25 (92.6%)	ns^d
No	2 (3.7%)	2 (7.4%)
Lymphatic drainage patterns
Ipsilateral axilla	51 (98.1%)	16 (64.0%)	< 0.0001
Aberrant drainage	10 (19.2%)	15 (60.0%)	< 0.001
Internal mammary chain (IMC)	7 (13.5%)	5 (20.0%)	ns
Contralateral axilla	1 (1.9%)	13 (52.0%)	< 0.0001
Intramammary	4 (7.7%)	2 (8.0%)	ns
Supraclavicular	0 (0%)	0 (0%)	ns
Contralateral IMC	0 (0%)	1 (4.0%)	ns
b) AX group^b
	Without RT	With RT
	N = 38	N = 17	P value
Visualization on lymphoscintigraphy
Yes	30 (78.9%)	14 (82.4%)	ns
No	8 (21.1%)	3 (17.6%)
Lymphatic drainage patterns
Ipsilateral axilla	19 (63.3%)	4 (28.6%)	< 0.05
Aberrant drainage	20 (66.7%)	13 (92.9%)	ns
Internal mammary chain (IMC)	17 (56.7%)	7 (50%)	ns
Contralateral axilla	2 (5.3%)	9 (64.3%)	< 0.0001
Intramammary	3 (10.0%)	0 (0%)	ns
Supraclavicular	1 (3.3%)	1 (7.1%)	ns
Contralateral IMC	0 (0%)	0 (0%)

Lymphatic drainage patterns were compared among the patients according to the presence or absence of previous radiotherapy in the non-AX group and the AX group. RT had little impact on the visualization rate of re-SLNs in both groups (Table 6a, b). In the non-AX group, lymphatic drainage to ipsilateral axilla was significantly decreased and aberrant drainage to contralateral axilla was significantly increased in patients with RT (Table 6a). In the AX group, re-SLNs were visualized at contralateral axilla more commonly in patients with RT (Table 6b)
^anon-AX group: patients with previous SLNB and no previous axillary surgery
^bAX group: patients with previous axillary lymph node dissection
^cRT: previous radiotherapy after breast-conserving surgery
^dns: no significant difference

ISSN: 1748-717X