PT - JOURNAL ARTICLE AU - NARA YOON AU - JIYOUNG KIM AU - LEE-SO MAENG AU - JOONG HYUN AHN AU - EUN SU PARK TI - Prominent Nucleoli and Non-glandular Feature Are Independent Predictors of PD-L1 Expression in Lung Adenocarcinoma AID - 10.21873/anticanres.12949 DP - 2018 Oct 01 TA - Anticancer Research PG - 6003--6008 VI - 38 IP - 10 4099 - http://ar.iiarjournals.org/content/38/10/6003.short 4100 - http://ar.iiarjournals.org/content/38/10/6003.full SO - Anticancer Res2018 Oct 01; 38 AB - Background/Aim: In patients with non-small cell lung cancer, relationships between PD-L1 (programmed death-ligand 1) expression and clinicopathological characteristics have been examined. However, the association between cytological features and PD-L1 expression remains unknown. Thus, the aim of this study was to investigate whether nuclear features might be correlated with PD-L1 expression in patients with advanced and inoperable lung adenocarcinoma using small biopsy specimens. Materials and Methods: Archived slides from 90 patients with lung adenocarcinoma who underwent small biopsy between October 2014 and May 2017 at the Incheon St. Mary's Hospital, were reviewed. PD-L1 expression was detected by immunohistochemistry using PD-L1 22C3 IHC assay. Associations of PD-L1 expression with pathological and molecular features (EGFR mutation, ALK and ROS-1 rearrangement) were statistically analyzed. Results: PD-L1 expression in tumor cells was positive in 33 of 90 cases (36.7%). Higher PD-L1 expression (≥50%) was more frequent in cases with marked nuclear pleomorphism (p<0.001), coarse chromatin pattern (p=0.006), predominant nucleoli (≥3 μm) (p<0.001), large nuclear diameter (>5× small lymphocyte) (p=0.006), non-glandular feature (p<0.001), and atypical mitosis (p=0.034). There were no significant correlations between PD-L1 positivity and molecular features. In multivariable logistic regression analysis, PD-L1 positivity was independently associated with prominent nucleoli (p=0.005) and non-glandular feature (p=0.007). Conclusion: Prominent nucleoli and non-glandular feature are independent predictors of PD-L1 expression in lung adenocarcinoma.