A New Treatment for Endoscopic Palliation of Colorectal Cancer

Patients with colorectal cancer (CRC) metastatic to the liver or lung often do not undergo surgical resection of their primary tumor. However, the primary tumor may continue to create symptoms from obstruction, bleeding, or pain.

Calcium electroporation has been used successfully to treat cutaneous metastasis as well as head and neck cancers. The technique involves injecting calcium chloride into the tumor, followed by short electrical pulses that make cell membranes permeable. Tumor tissue appears preferentially susceptible to injury compared to normal tissue.

In this study, 6 patients with metastatic CRC and symptoms from their primary lesion received 10 treatments total. After needle injection of calcium chloride, the single-use EndoVe device (Mirai Medical, Cork, Ireland) is attached to the endoscope. The device is connected to a vacuum that draws in tumor tissue, followed by application of the electrical pulses.

In this phase 1 study, there were no serious adverse events. Two patients had a fever and general malaise for up to 24 hours.

Five of 6 patients had symptom relief, and 4 had a partial endoscopic response at follow-up. One patient had a complete endoscopic response, with no visible residual tumor tissue, and only ulcer and granulation tissue on biopsy. Follow-up radiographic studies showed similar results, and there was no increase in cell-free DNA after treatment.