Patients with PDAC showed elevated CEACAM 6 serum expression compared to both, CP and BD (PDAC median 2.90 μg/l, range 1.34–5.46 μg/l; CP median 2.25 μg/l, range 0.77–5.15; BD median 2.34 μg/l, range 1.25–6.99 μg/l; P = 0.06 and P = 0.029, respectively). The gene discussed is CP; the disease is Behcet disease.