Table 1. Summary of the regional lymph nodes irradiation studies.

	Whelan et al.[5], 2015	Poortmans et al.[6], 2015	Hennequin et al.[8], 2013	Stemmer et al.[7], 2003	Thorsen et al.[9], 2016
Study Types	Randomized	Randomized	Randomized	Prospective Nonrandomized	Prospective Nonrandomized
Enrolling Year	2000–2007	1996–2004	1991–1997	1994–1998	2003–2007
Eligible Criteria	ALN+/ High-risk ALN-	ALN+/ Central or medial tumor	ALN+/ Central or medial tumor	Stage II-IIIA	ALN+ Left-side IMNI Right-side no IMNI
No. of pts	1,832	4,004	1,334	100	3,089
Median age (year)	54	54	57	45	56
Breast Surgery	100% Lumpectomy	76.1% Lumpectomy 23.9% Mastectomy	100% Mastectomy	54% Lumpectomy 46% Mastectomy	65% Mastectomy 35% Lumpectomy
Systemic Treatment	CT (91%); HT (76%)	CT (25%); HT (30%); CT+HT (30%)	CT (61%); HT (52%)	CT (100%); HT (42%)	CT (19%); CT+HT (47%)
ALN Status
N0	9.7%	44.4%	24.8%	0%	0%
N1–3+	85.0%	43.1%	44.1%	0%	58.9%
N ≥ 4+	5.3%	12.5%	31.1%	100%	41.1%
Target Range	Breast ± RLN	Breast/chest wall ± RLN	Chest wall + SCV LN ± IMN	Breast/chest wall + SCV LN ± IMN	Breast/chest wall + SCV LN ± IMN
Intercostal Spaces of IMNI	1–3	1–5 (LIQ) 1–3 (other)	1–5	1–5	1–4
Dose of Breast/Chest wall	50 Gy/25 fx	50 Gy/25 fx	Base on the center	50.4 Gy/28 fx	48 Gy/24 fx
Dose of IMNI	45 Gy/25 fx	50 Gy/25 fx	45 Gy/25 fx	50.4 Gy/28 fx	48 Gy/24 fx
Median FU	9.5	10.9	11.3	6.4	8.9
OS % Improved	1%, P = 0.38	1.6%, P = 0.06	3.3%, P = 0.8	14%, P = 0.8	3.7%, P = 0.005
Other Outcomes Improved	DFS 5%, P= 0.01; BCM 1%, P= 0.11	DFS 3%, P= 0.04; DMFS 3%,P = 0.02	DFS 3.3%, P = 0.35	DFS 21%, P = 0.02	BCM 2.5%, P = 0.03; DRR 2.3%, P = 0.07

Abbreviations: ALN Axillary lymph node; IMNI Internal mammary lymph node irradiation; CT chemotherapy; HT hormonal therapy; RLN Regional lymph node; SCV LN supraclavicular lymph node; IMN Internal mammary lymph node; LIQ lower inner quadrant; fx fractions; FU Following-up; OS overall survival; DFS disease free survival; BCM breast cancer mortality; DMFS distant recurrence free survival; DR distant recurrence rate