CD8A and pachyonychia congenita: Studies have shown that the presence of CTLs (CD8+ TILs) in the tissue of solid tumors is associated with a better prognosis due to their cytotoxic and anti-tumor activity, while in PC, this has not yet been fully established, and some studies have reported that increase of CTLs in the prostate TME has led to worsening of the condition in patients (25–27).