Minimally Invasive Electrochemotherapy Procedure for Treating Nasal Duct Tumors in Dogs using a Single Needle Electrode

Background Nasal cavity tumors are usually diagnosed late, when they already have infiltrated adjacent tissues thus requiring very aggressive treatments with serious side effects. Here we use electrochemotherapy (ECT), a well demonstrated treatment modality for superficial tumors. Materials and methods In the case of deep-seated tumors, the main limitation of ECT is reaching the tumor with an appropriate electric field. To overcome this limitation we introduce the single needle electrode (SiNE), a minimally invasive device that can deliver an appropriate electric field with a simple procedure. Twenty-one canine patients with spontaneous tumors were selected, eleven were treated using the SiNE with ECT, and ten with surgery plus adjuvant chemotherapy as a control group. Results In the SiNE group, 27% achieved a complete response, 64% had a partial response, and 9% had a stable disease. This means that 91% of objective responses were obtained. The mean overall survival was 16.86 months (4-32 months, median 16.5 months), with a survival rate significantly higher (p = 0.0008) when compared with control group. The only side effect observed was the inflammation of the treated nasal passage, which was controlled with corticosteroid therapy for one week. One year after the treatment, 60% of the canine of the SiNE group vs. 10% of the control group remained alive, and after the 32 months follow-up, the survival rate were 30% and 0%, respectively. Conclusions ECT with the SiNE can be safely used in canine to treat nasal tumors with encouraging results.