Table 2.

APM expression and CD8⁺ T cell infiltration in primary breast cancers with or without brain metastases

	Without brain mets (N = 50)	With brain mets (N = 15)	P value*
HLA	0.81 ± 0.89	0.73 ± 1.02	0.61
β2m	0.99 ± 0.90	0.23 ± 0.56	<0.001
Tapasin	0.91 ± 0.97	0.47 ± 0.61	0.13
TAP1	1.55 ± 0.90	0.43 ± 0.70	<0.001
TAP2	0.72 ± 0.69	1.20 ± 0.88	0.061
LMP2	1.41 ± 0.73	1.37 ± 0.74	0.87
Calnexin	1.99 ± 0.76	1.33 ± 1.10	0.03
CD8+ T cells/10HPF†	130.04 ± 139.15	38.80 ± 50.54	<0.001

Data indicate mean scores ± SD

* Mann–Whitney U test. Bold: Statistically significant (P < 0.05)

† HPF high power field