Table 2.

PD-1 and PD-L1 expression in breast cancers, according to the molecular subtype

Breast cancer subtypes (n = 116)PD-1 expression/hpf (TILs; % and range)PD-L1 (tumor cells; %)Concurrent PD-1 and PD-L1 expression (%)
Luminal tumors (n = 58)
 Luminal A (n = 33)25% (1–>10)33%13%
 Luminal B (n = 25)44% (1–20)33%17%
HER2 positive (n = 5)60% (1–9)20%20%
Triple-negative (n = 53)70% (1–20)a59%a45%a

Abbreviation: hpf, high-power fields.

  • aSignificantly higher than in luminal tumors.