Figure 3.

Intraprocedural challenges of ECT in BCC. As a principle, effective ECT treatment delivery relies on adequate chemotherapy distribution within the tumour (following i.v. or i.t. administration) and complete coverage with electric fields (electroporation). In this regard, lower response rates are associated with previous radiotherapy (likely due to its effect on microcirculation) and the insufficient electroporation of tumour margins, an aspect closely associated with the modalities of electrode application. Generally, the extent and depth of electrode insertion are operator-dependent and based on clinical judgment. (a) An example of nodular BCC with well-circumscribed areas of cancer cells (black arrows) treated with a fixed-length electrode. In this case, the actual BCC depth may be underestimated, thus leaving deep portions of the tumour untreated. (b) An example of infiltrative BCC in which the actual extension of the tumour may be challenging to discriminate with potential repercussions on the coverage of lateral tumour margins. Red arrows indicate the potential depth (a) or extension (b) of electrode application.