PD-L1 expression and survival in unresectable/recurrent gastric cancer treated by 1st-line treatment without immune checkpoint inhibitors: JCOG1013A1
BACKGROUND: The prognostic significance of PD-L1 expression in unresectable/recurrent gastric cancer treated by first-line chemotherapy without an immune checkpoint inhibitor (ICI) remains unclear. The phase III trial JCOG1013 demonstrated no overall survival (OS) or progression-free survival (PFS) benefit of docetaxel/cisplatin/S-1 over cisplatin/S-1. This ancillary analysis of JCOG 1013 evaluated the prognostic value of PD-L1 expression. METHODS: PD-L1 expression was assessed in pretreatment tumor specimens using the Dako 28-8 pharmDx assay. Combined positive score (CPS) and tumor proportion score (TPS) were calculated. PD-L1 positivity was defined as CPS ≥ 5 or TPS ≥ 1%. Univariable and multivariable analyses were performed for OS and PFS. RESULTS: Among 741 patients enrolled in JCOG1013, 540 patients were included. In univariable analyses, neither CPS ≥ 5 nor TPS ≥ 1% was significantly associated with OS or PFS. In multivariable analyses, CPS ≥ 5 was not significantly associated with OS (HR 0.86, 95% CI 0.71-1.04; p = 0.127) or PFS (HR 0.92, 95% CI 0.77-1.11; p = 0.392); however, TPS ≥ 1% was significantly associated with longer OS (HR 0.78, 95% CI 0.62-0.97; p = 0.028) and PFS (HR 0.76, 95% CI 0.62-0.94; p = 0.012). CONCLUSIONS: TPS ≥ 1% is an independent favorable prognostic factor for survival in patients with unresectable/recurrent gastric cancer receiving chemotherapy alone. CLINICAL TRIAL REGISTRATION: UMIN000007652.
Authors
- Shigeki Sekine (ORCID: https://orcid.org/0000-0003-0884-8981)
- Hisato Kawakami (ORCID: https://orcid.org/0000-0002-3280-4850)
- Narikazu Boku (ORCID: https://orcid.org/0000-0002-1438-707X)
- Mizutomo Azuma
- Masanori Terashima (ORCID: https://orcid.org/0000-0002-2967-8267)
- Kengo Nagashima (ORCID: https://orcid.org/0000-0003-4529-9045)
- Takaki Yoshikawa (ORCID: https://orcid.org/0000-0003-1936-9484)
- Yukinori Kurokawa (ORCID: https://orcid.org/0000-0002-2883-0132)
- Hidekazu Hirano (ORCID: https://orcid.org/0000-0003-1343-1419)
- Shigenori Kadowaki (ORCID: https://orcid.org/0000-0001-9923-5309)
- Nobuyoshi Hiraoka (ORCID: https://orcid.org/0000-0003-4215-4385)
- Keisuke Kanato
- Toshiyasu Ojima (ORCID: https://orcid.org/0000-0003-4958-9525)
- Satoru Iwasa (ORCID: https://orcid.org/0000-0003-3863-9582)
- Naoki Takahashi (ORCID: https://orcid.org/0000-0001-6377-9507)
- Daisuke Takahari (ORCID: https://orcid.org/0000-0002-2492-6014)
- Yasuhide Yamada (ORCID: https://orcid.org/0000-0003-0692-8419)
- Nozomu Machida
- Hiroaki Hata
- Takahiro Kinoshita
Institutions
- Tokyo University of Science (JP)
- Wakayama Medical University (JP)
- Tohoku University (JP)
- Kyoto Medical Center (JP)
- Kanagawa Prefectural Hospital Organization (JP)
- Institute for Security Studies (KE)
- Shizuoka Cancer Center (JP)
- Keio University Hospital (JP)
- Kitasato University Hospital (JP)
- Saitama Cancer Center (JP)
- Aichi Cancer Center (JP)
- National Cancer Center Hospital East (JP)
- Japan Clinical Cancer Research Organization (JP)
- Tokyo National Hospital (JP)
- Japanese Foundation For Cancer Research (JP)
- Kanagawa Cancer Center
- Kindai University (JP)
- The University of Osaka (JP)
Publication Details
- Journal
- British Journal of Cancer
- Published
- 2026-09-04
- DOI
- https://doi.org/10.1038/s41416-026-03607-7
- Primary Topic
- Cancer Immunotherapy and Biomarkers
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Amgen
- Bristol-Myers Squibb
- Eli Lilly and Company
- AstraZeneca
- GlaxoSmithKline
- Medpace
- Merck KGaA
- Taiho Pharmaceutical
- National Center for Global Health and Medicine
- Miyarisan Pharmaceutical
- BeiGene
- Boehringer Ingelheim Japan
- Seagen
- Daiichi-Sankyo
- Eisai
- Astellas Pharma
- Otsuka Pharmaceutical
- Ono Pharmaceutical
- Chugai Pharmaceutical
- Eli Lilly Japan
- Bayer Yakuhin
- Daiichi Sankyo Europe