Virtual Library
Start Your Search
R. Matsumoto
Author of
-
+
P1.08 - Poster Session/ Thymoma, Mesothelioma and Other Thoracic Malignancies (ID 224)
- Event: WCLC 2015
- Type: Poster
- Track: Thymoma, Mesothelioma and Other Thoracic Malignancies
- Presentations: 1
- Moderators:
- Coordinates: 9/07/2015, 09:30 - 17:00, Exhibit Hall (Hall B+C)
-
+
P1.08-007 - Programmed Cell Death 1 Ligand 1 (PD-L1) Expression in Thymoma (ID 46)
09:30 - 09:30 | Author(s): R. Matsumoto
- Abstract
Background:
Programmed cell death 1 ligand-1 (PD-L1) has been reported to be expressed in various malignancies, and is considered to be a prognostic factor and an immunotherapeutic target. The aim of this study was to characterize PD-L1 expression in thymoma and statistical associations between this expression and clinical features.
Methods:
We reviewed formalin-fixed paraffin-embedded tissue specimens from 82 thymoma cases at Kurume University. PD-L1 expression was evaluated by immunohistochemistry (IHC). Statistical associations between PD-L1 expression and clinicopathological features were evaluated by using chi-square test and Fisher’s exact test. Disease-free survival (DFS) analysis, the end event of which is recurrence, was performed by the Kaplan-Meier method.
Results:
A total of 44 thymoma cases (54%) revealed high PD-L1 expression by IHC. No significant differences were observed between high and low PD-L1 expression with respect to sex (P = 0.938), age (P = 1.000), symptomatic myasthenia gravis (P = 0.471), anti-acetylcholine receptor antibody titer (P = 0.513), primary tumor size (P = 0.527), or curability (P = 0.620). However, high PD-L1 expression was statistically associated with Masaoka’s stage III/IV disease (P = 0.043) and WHO type B2 or B3 thymoma (P = 0.044). DFS after complete resection in high PD-L1 expression cases was significantly worse than that in low PD-L1 expression cases (P = 0.021). Figure 1Figure 2
Conclusion:
Characterization of PD-L1 expression in thymoma should enable more effective clinical approaches, including prognostic stratification of patients and use of anti-PD-L1 antibody immunotherapy.