Low GATA6 IHC expression was associated with shorter overall survival [median OS 6.2 months for patients with GATA6 low tumors vs. 11.5 months for patients with GATA6 high tumors, HR 1.66 (95% CI 1.15–2.40), P = 0.007]. Progression appears to be higher in GATA6-low tumors compared to GATA6-high tumors in patients treated with mFFX (P = 0.024) but not in patients treated with gemcitabine regimens....In patients who received first-line modified FOLFIRINOX (mFFX; n = 63), median OS was 7.6 months in GATA6-low versus 14.8 months in GATA6-high subgroups [HR 1.90; 95% confidence interval (CI) 1.0729–3.3526; P = 0.025)...our study demonstrates that GATA6 IHC can be used as a single biomarker to predict clinical outcome in advanced PDAC...