Endoscopic Assisted Calcium Electroporation in Esophageal Cancer

In this pilot study, patients with non-curable esophageal cancer will be treated with endoscopic assisted calcium electroporation (CaEP). CaEP is a novel cancer treatment where intratumoral injection with calcium is combined with locally applied electrical pulses, in order to increase calcium influx which leads to tumor necrosis. It is hypothesized that: * Endoscopic assisted CaEP is a safe and feasible procedure in patients with non-curable esophageal cancer * CaEP debulks the tumor, facilitating the patient's ability to eat and drink In this single-arm pilot study, eight patients will be treated.