Feline squamous cell carcinoma (SCC) is currently treated with surgery, radiation therapy and electrochemotherapy (ECT). Both the efficacy and/or safety of ECT were evaluated as a sole therapy with bleomycin to treat feline nasal planum SCC (npSCC). Sixty-one cats were enrolled. Local treatment response was evaluated as complete remission (CR), partial remission (PR) or stable disease (SD). Recurrence rate (RR), disease-free interval (DFI) and progression free survival (PFS) were calculated. A six-point scale was used for ECT toxicity. The median tumor size was 1.5 cm. CR was achieved in 65.6% of cases, PR in 31.1% and SD in 3.3%. The overall response rate was 96.7%, RR was 22.5%, median DFI was 136 days, and median PFS was 65.5 days. ECT toxicity was ≤2 in 51% of cats. Tumor recurrence/progression (p = 0.014) and local treatment response (PR: p < 0.001; SD: p < 0.001) influenced survival time. Cats with toxicity >2 showed a higher probability of tumor recurrence/progression. Tumor-related death was higher in cats with PR (p < 0.001) and recurrence/progression (p = 0.002), in ECT treatment with 1 Hz (p = 0.035) and 1200 V/cm (p = 0.011) or 1300 V/cm (p = 0.016). Tumor size influenced local treatment response (p = 0.008) and toxicity (p < 0.001). ECT is an effective treatment for feline npSCCs and should be considered as the first-line procedure for low-stage tumors.
Electrochemotherapy (ECT) is a technique that combines chemotherapy with local application of specific electric pulses with the aim of increasing the permeability of the plasma membrane in a reversible way, improving the influx of chemotherapeutic drugs into the cytoplasm and potentiating their cytotoxic effects. This technique has broadened the range of possible treatments for oncological patients, either on its own or as adjuvant to surgical procedures. It is especially useful in tumors located in regions with only a small surgical safety margin, such as the limb extremities, skull, oral cavity, neck and perianal region, among others. ECT makes it feasible to perform procedures more conservatively, or even to perform otherwise infeasible procedures, by expanding the margins without removing healthy tissues. The objective of this paper is to provide a brief bibliographic review of the principles, applications and future possibilities of electrochemotherapy, helping to disseminate pertinent information about this relatively new technique for the treatment of cancer.