Differences in the electric potential of pancreatic head cancer tissues

Identifying the electrical properties of cancer relies on the understanding of the electric potential (EP) of cancer tissues. This study aimed to investigate the EP properties in 49 pancreatic head cancer tissues using a digital multimetre. The anode was placed at the central side of the tumour, and the electric potential differences (EPDs) between cancerous and cancerous, cancerous and noncancerous, and noncancerous and noncancerous lesions at approximately 1-cm intervals following resection were evaluated. Pathological evaluation identified 30 of these samples as pancreatic invasive ductal carcinoma (PIDC, 10 without preoperative chemotherapy and 20 after chemotherapy), seven other pancreatic cancers, three tumours of Vater’s ampulla (VA), and eight extrahepatic cholangiocarcinoma (EHCC) samples. We also evaluated the differences in pH for cancerous and noncancerous lesions in nine PIDC samples. Our data suggest that the EP of pancreatic cancerous tissues is higher than that of noncancerous tissues, especially in PIDCs. We also noted that EPD was the highest when comparing cancerous and noncancerous lesions. Additionally, PIDC tissues presented with low pH; the pH difference between cancerous and noncancerous sites was significantly correlated with EPD (P = 0.011). These EPDs were also correlated with tumour size in PIDCs and inversely correlated with their response to chemotherapy. The EP values for both the cancerous and noncancerous sites in both the VA tumours and EHCC samples were not significantly different, whereas EPD in PIDC correlated with tumour extension and viable tumour content, suggesting that EPD might be useful for evaluating the viability and effectiveness of neoadjuvant chemotherapy.