AUTHOR=Gou Miaomiao , Zhang Yong , Liu Tiee , Qu Tongtong , Si Haiyan , Wang Zhikuan , Yan Huan , Qian Niansong , Dai Guanghai 

TITLE=The Prognostic Value of Pre-treatment Hemoglobin (Hb) in Patients With Advanced or Metastatic Gastric Cancer Treated With Immunotherapy

JOURNAL=Frontiers in Oncology

VOLUME=Volume 11 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2021.655716

DOI=10.3389/fonc.2021.655716

ISSN=2234-943X

ABSTRACT=Background
The biomarker such as prevailing PD-L1 expression and TMB was of controversy to predict the benefit population from Immunotherapy with advancedor or metastatic gastric cancer  (AGC or MGC). Our study aims to investigate whether pretreatment hemoglobin (Hb) level associated with survival exposure to immunotherapy in patients with AGC and MGC . 
Methods
We retrospectively reviewed patients with AGC or MGC receiving PD-1 inhibitor. at our center  The Propensity Score Matching (PSM) (1:1) was performed to balance  baseline confounding factors. Progression-free survival (PFS) and overall survival (OS) was analyzed among different Hb level (normal Hb group and decreased Hb group). Objective response rate (ORR), disease control rate (DCR) were also analyzed. Univariate analysis and multivariate analysis were performed further to validate the prognostic value of Hb level. 
Results
We included 137 patients with AGC and MGC who received PD-1 inhibitors (including Pembrolizumab, Nivolumab, Sintilimab, Toripalimab) in this study. After PSM matching, there were no significant differences between the two groups for baseline characteristics. The median PFS was 7.8 months in the normal Hb level group and 4.3 months in the decreased Hb group (HR 95% CI 0.5(0.31, 0.81), P=0.004). The OS was 14.4 months with normal Hb level as compared with 8.2 months with decreased Hb level( HR 95% CI 0.59(0.37, 0.94), P=0.024). The ORR was 40.7% and DCR was 83.0% in the normal Hb group, while the ORR was 25.5% and DCR was 85.1% in the decreased Hb group. No significant differences were found in the ORR and DCR between the two groups (P=0.127, P=0.779). Univariate analysis and multivariate analysis showed that Hb level was only independent predictor for PFS and was significant prognostic factor influencing the OS. Only when patients had normal Hb level, anti-pd-1 monotherapy or combined with chemotherapy was superior to anti-pd-1 plus anti-angiogenic therapy with respect to PFS (P=0.031) and OS( P=0.001). 
Conclusions
    Our study have demonstrated that pretreatment Hb level was an independent prognostic biomarker in term of PFS and OS with immunotherapy for AGC and MGC patients. Correction of anemia for GC patients as immunotherapy would be a strategy to improve the survival.