In a preclinical study using a syngeneic orthotopic PC mouse model, the combination of anti-PD-1 antibodies (10 mg/kg) and hypofractionated RT (8 Gy × 3 fractions delivered daily for 3 days, at a dose rate of 3 Gy/minute) improved survival compared with anti-PD-1 or RT alone. Here, PDCD1 is linked to pachyonychia congenita.