Association between PD-L1 expression and lymph node metastasis in cutaneous squamous cell carcinoma

Area of Science:

• Oncology
• Immunology
• Dermatology

Background:

• Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer.
• Programmed cell death ligand 1 (PD-L1) is an immune checkpoint protein implicated in tumor immune evasion.
• The role of PD-L1 expression in cSCC progression remains incompletely understood.

Purpose of the Study:

• To investigate the association between PD-L1 expression in cSCC and clinicopathological variables.
• To determine if PD-L1 expression is a predictive marker for disease progression.

Main Methods:

• Immunohistochemistry was used to assess PD-L1 expression in tumor cells (TCs) and tumor-infiltrating immune cells (ICs) in 46 cSCC cases.
• PD-L1 expression was evaluated using both intensity and proportion scoring for TCs, and proportion scoring for ICs.
• Fisher's exact test was employed for statistical analysis of associations.

Main Results:

• High PD-L1 intensity in TCs was observed in 39.1% of cases and correlated significantly with lymph node metastasis (P=0.008) and female gender (P=0.017).
• PD-L1 expression proportions in TCs or ICs did not show a significant relationship with lymph node metastasis.
• Multivariate analysis identified high PD-L1 intensity in TCs as an independent risk factor for lymph node metastasis.

Conclusions:

• High intensity PD-L1 expression in tumor cells is significantly associated with lymph node metastasis in cSCC.
• PD-L1 intensity may serve as a valuable prognostic biomarker for predicting metastasis risk in cSCC.