ALDH1A1 and carcinoma: The main findings of the present study were as follows: (1) positive ALDH1A1 expression was related to positive PD-L1 expression and HTILs, (2) pathologic complete response was more frequently achieved by patients with positive ALDH1A1 carcinomas, (3) smaller tumors more frequently showed positive ALDH1A1 and PD-L1 expression and HTILs, and (4) patients with HTILs have better DFS than LTIL cases.