Güncel Patoloji Dergisi
2026, Cilt 10, Sayı 2
Pathologist–Artificial Intelligence Concordance in PD-L1 Scoring in Non-Small Cell Lung Carcinoma: A Single-Center Validation Study
1 Atatürk Üniversitesi Tıp Fakültesi, Tıbbi Patoloji Anabilim Dalı, Erzurum, Türkiye
2 Van Yüzüncü Yıl Üniversitesi Tıp Fakültesi, Tıbbi Patoloji Anabilim Dalı, Van, Türkiye
3 Bursa Şehir Hastanesi Tıbbi Patoloji Laboratuvarı, Bursa, Türkiye
4 Erzurum Şehir Hastanesi Tıbbi Patoloji Laboratuvarı, Erzurum, Türkiye
5 Ankara Atatürk Sanatoryumu Eğitim ve Araştırma Hastanesi Patoloji Laboratuvarı, Ankara, Türkiye
6 Iğdır Dr. Nevruz Erez Devlet Hastanesi Tıbbi Patoloji Laboratuvarı, Iğdır, Türkiye
7 Yeni Yüzyıl Üniversitesi Tıp Fakültesi, Tıbbi Patoloji Anabilim Dalı, İstanbul, Türkiye
8 Atatürk Üniversitesi Tıp Fakültesi, Göğüs Hastalıkları Anabilim Dalı, Erzurum, Türkiye
9 Kars Harakani Devlet Hastanesi Patoloji Laboratuvarı, Kars, Türkiye
10 Acıbadem Bursa Hastanesi Onkoloji Kliniği, Bursa, Türkiye
DOI :
10.5146/jcpath.2026.728
Objective: Classification of programmed death ligand 1 (PD-L1) tumor proportion scores at clinical thresholds may vary by evaluator. This study assessed concordance between the primary pathologist assessment (KY-1) and the Gemini 3.1 Pro artificial intelligence model (YZ), and explored a blinded second pathologist assessment (KY-2) in discordant cases. Material and Methods: This single-center retrospective validation study included 25 archival cases. Four-micrometer formalin-fixed paraffin-embedded sections were stained with CAL10 and ultraView Universal DAB on a BenchMark ULTRA platform. At least 10 Full HD images covering all tumor-bearing areas and collectively containing at least 100 viable tumor cells were captured per case using a 20× objective. Each Turkish prompt was run once, and a single YZ output was recorded. Scores were categorized as <1%, 1–49%, or ≥50%. KY-1–YZ agreement was assessed with Cohen’s kappa and exact McNemar tests; the KY-2 subset was analyzed exploratorily. Results: KY-1 classified 15 cases as negative, 6 as low-positive, and 4 as high-positive; YZ classified 14, 5, and 6 cases, respectively. Exact agreement was 16/25 (64.0%), Cohen’s kappa was 0.377, and quadratically weighted kappa was 0.531. YZ assigned a higher category in five cases and a lower category in four. Marginal differences were absent at the 1% and 50% thresholds (p=1.000; p=0.625). In eight discordant cases with KY-2 data, KY-2 matched KY-1 in seven cases (kappa = 0.784); the KY-2–YZ kappa was -0.366. Conclusion: KY-1 and YZ showed limited-to-moderate agreement, without a systematic directional difference at clinical thresholds. KY-2 reproduced KY-1 in most selected discordant cases. Because no independent multi-reader consensus standard was available, YZ accuracy could not be established. Local validation, standardized imaging and prompting, and blinded adjudication are required before clinical implementation.
Anahtar Kelimeler :
Carcinoma, Non-small-cell lung, Programmed cell death 1 ligand 1 protein, Immunohistochemistry, Observer variation, Artificial intelligence
2 Van Yüzüncü Yıl Üniversitesi Tıp Fakültesi, Tıbbi Patoloji Anabilim Dalı, Van, Türkiye
3 Bursa Şehir Hastanesi Tıbbi Patoloji Laboratuvarı, Bursa, Türkiye
4 Erzurum Şehir Hastanesi Tıbbi Patoloji Laboratuvarı, Erzurum, Türkiye
5 Ankara Atatürk Sanatoryumu Eğitim ve Araştırma Hastanesi Patoloji Laboratuvarı, Ankara, Türkiye
6 Iğdır Dr. Nevruz Erez Devlet Hastanesi Tıbbi Patoloji Laboratuvarı, Iğdır, Türkiye
7 Yeni Yüzyıl Üniversitesi Tıp Fakültesi, Tıbbi Patoloji Anabilim Dalı, İstanbul, Türkiye
8 Atatürk Üniversitesi Tıp Fakültesi, Göğüs Hastalıkları Anabilim Dalı, Erzurum, Türkiye
9 Kars Harakani Devlet Hastanesi Patoloji Laboratuvarı, Kars, Türkiye
10 Acıbadem Bursa Hastanesi Onkoloji Kliniği, Bursa, Türkiye
