PCNA and neoplasm: Compared with that in the tumor group (0.1591±0.0032; 0.0981±0.0031), the positive expression of Ki67 (Fig 6) and PCNA (Fig 6) in the nsPEF group was significantly decreased at days 5 (0.0580±0.0027, P < 0.001; 0.0477±0.0024, P < 0.01) and 7 (0.0478±0.0010, P < 0.001; 0.0229±0.0014, P < 0.01), and the positive expression of Ki67 in the RFA group was also decreased to some degree (0.0791±0.0058, P < 0.001).