Conclusion
Positive surgical margin and expression of PD-1+ T cells were associated with CIN persistence/recurrence after conization.
Methods
Medical records of 652 patients diagnosed with CIN and underwent conization were reviewed. The associations between clinicopathologic parameters (e.g., age, parity, initial HPV load, etc.) and persistence/recurrence of CIN were analyzed. Expression of PD-1, PD-L1, and PD-L2 was assessed on 100 conization specimens by immunohistochemistry (IHC) in women matched for propensity-score (50 with persistence/recurrence and 50 without).
Objective
Impaired local cellular immunity contributes to persistent human papillomavirus (HPV) infection and development of cervical intraepithelial neoplasia (CIN). Programmed death-1 (PD-1) and its ligands PD-ligand-1 (L1) and PD-L2 are negative regulators of T cell activity in various cancers, but few studies exist. The aim of this study was to determine the clinicopathologic and immunologic parameters (PD-1, PD-L1, and PD-L2) related to the persistence/recurrence of CIN after conization.
Results
Initial HPV load (>1,000 relative light unit) and positive margin were shown to be significantly associated with CIN persistence/recurrence (p=0.012 and p<0.001, respectively). Multivariate analysis showed that margin status was an independent predictor of persistence/recurrence (hazard ratio=8.86; 95% confidence interval=1.67-16.81; p<0.001). On IHC analysis, none of the patients expressed PD-L1. PD-1+ T cells were observed in 25 of 100 patients. Also, PD-1+ T cells were significantly correlated with increasing grade of CIN (p=0.031). In addition, patients with persistence/recurrence had increased expression of PD-1 compared with those without (36% vs. 14%, respectively; p=0.020). Although PD-L2 expression did not differ between 2 groups, it was significantly higher in patients with high-grade CIN compared to low-grade (34.7% vs. 12%, respectively; p=0.041).