title: PD-L1 expression of the residual tumor serves as a prognostic marker in local advanced breast cancer after neoadjuvant chemotherapy.
abstract: This study sought to investigate the prevalence of programmed death ligand 1 (PD-L1) and its prognostic value in patients with residual tumors after neoadjuvant chemotherapy (NCT) for locally advanced breast cancer. A total of 309 patients considered as non-pathological complete responders (non-pCR) after NCT followed by mastectomy were selected. The expression of PD-L1 and tumor-infiltrating lymphocytes (TILs) in residual breast cancer cells was assessed by immunohistochemistry in surgical specimens. The median density was used to classify PD-L1 expression from low to high. The prognostic value of various clinicopathological factors was evaluated. The expression of PD-L1 was more commonly observed in patients with low levels of total TILs (p < 0.001), high levels of FOXP3+ TILs (p < 0.001) and low levels of CD8+ TILs (p < 0.001). This served as an independent prognostic factor for both relapse-free survival (Hazard ratio = 1.824, p = 0.013) and overall survival (OS) (Hazard ratio = 2.585, p = 0.001). High expression of PD-L1 was correlated to worse survival, which is most significantly observed in triple-negative patients. Patients classified as PD-L1-high/CD8-low exhibited relatively unfavorable survival, whereas patients with either low expression of PD-L1 or high expression of CD8 had similar outcomes. PD-L1 expression in residual tumor can be used as a prognostic marker in non-pCR patients after receiving NCT for breast cancer, which highlights the importance of immune evasion in the therapeutic vulnerability of chemoresistant cancer cells as well as the potential of anti-PD-L1 treatments in non-pCR responders.
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai, People's Republic of China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai, People's Republic of China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
authors.forename: Ruo-Xi
authors.initials: RX
authors.lastname: Wang
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai, People's Republic of China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.|Department of Pathology, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai, People's Republic of China.
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Yang
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center/Cancer Institute, Shanghai, People's Republic of China.|Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.|Institutes of Biomedical Science, Fudan University, Shanghai, People's Republic of China.
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Shao
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D060890:B7-H1 Antigen / Q000096:biosynthesis*; D001943:Breast Neoplasms / Q000737:chemistry* / Q000188:drug therapy / Q000401:mortality / Q000601:surgery; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology*; D003131:Combined Modality Therapy; D005260:Female; D051858:Forkhead Transcription Factors / Q000032:analysis; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision; D016246:Lymphocytes, Tumor-Infiltrating / Q000737:chemistry; D008408:Mastectomy; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D018365:Neoplasm, Residual; D011379:Prognosis; D012189:Retrospective Studies; D064726:Triple Negative Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000401:mortality / Q000601:surgery; D059016:Tumor Microenvironment
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D009363:Neoplasm Proteins
keywords: PD-L1; TILs; breast cancer; neoadjuvant chemotherapy; prognosis