Prognostic Impact of Human Lymphocyte Antigen (HLA) Class I Expression in Patients With Breast Cancer.

Background/aim: Various biomarkers are utilized in the field of breast cancer. Human lymphocyte antigen (HLA) class I molecules have a critical role in cancer immune surveillance. Therefore, this study aimed to assess the HLA class I expression and analyze the correlation with clinicopathologic factors in breast cancer.

Patients and methods: We investigated the clinical pathology archives of 150 consecutive patients with breast cancer who underwent a curative operation at the Sapporo Medical University, Japan, from January 2012 to December 2014. Immunohistochemical staining was used to evaluate HLA class I expression and CD8-positive T cell infiltration. The Pearson χ² test was used to assess HLA class I expression level and clinicopathological parameters. The Kaplan-Meier method was used to evaluate survival and the log-rank test to analyze the differences between survival curves.

Results: Patients with dull/negative HLA class I had significantly poor disease-free survival (DFS) compared with those with positive HLA class I (p=0.0073). Univariate analyses revealed that pT, pN, positive lymphatic invasion, and dull/negative HLA class I were significantly associated with DFS. Multivariate analyses revealed dull/negative HLA class I as an independent poor prognostic factor (hazard ratio=2.75, 95% confidence interval=1.30-5.80, p=0.008).

Conclusion: HLA class I expression level may have a very sensitive prognostic effect on patients with breast cancer.