Table 3. Subtype/immunohistochemistry of 26 archival NF1 breast cancer tissue samples by age group.

	All patients	Age <40	Age 40–50	Age >50
Patient age	n (%/all)	n (%/age group)	n (%/age group)	n (%/age group)
n (%/all)	26 (100%)	6 (23.1%)	6 (23.1%)	14 (53.8%)
Histological type
Ductal	23 (88.5%)
Lobular	2 (7.7%)
Other	1 (3.8%)
Breast cancer subtype
Luminal A	4 (15.4%)	0	1 (16.7%)	3 (21.4%)
Luminal B	9 (34.6%)	2 (33.3%)	4 (66.7%)	3 (21.4%)
HER2 subtype	8 (30.8%)	3 (50.0%)	1 (16.7%)	4 (28.6%)
Basal-like	4 (15.4%)	1 (16.7%)	0	3 (21.4%)
Triple-negative, other than basal-like	1 (3.8%)	0	0	1 (7.1%)
Ki-67
<20%	9 (34.6%)	1 (16.7%)	3 (50.0%)	5 (35.7%)
>20%	17 (65.4%)	5 (83.3%)	3 (50.0%)	9 (64.3%)
Grade
I	1 (3.8%)	0	0	1 (7.1%)
II	11 (42.3%)	2 (33.3%)	4 (66.7%)	5 (35.7%)
III	14 (53.8%)	4 (66.7%)	2 (33.3%)	8 (57.1%)

Abbreviations: HER2=human epidermal growth factor receptor 2; NF1=neurofibromatosis 1.