2 articles - one is Irreversible electroporation on canine, and second is Reversible electroporation combined with direct intratumoral injection of bleomycine. Both cases are resulted in complete response.
Ultrasound guidance facilitated electrode placement, with the center energized (2.5-cm exposure length) and one side grounded at a time (1.5-cm exposure), for a total of two pulse sets. Pulses were synchronized to 500s after the R-peak wave of the patient’s cardiac rhythm. Both IRE treatments resulted in progressive coagulative tumor necrosis in the periods of 24 to 48 hours post therapy , and the majority of skeletal muscle at the margin of the tumor remained viable. In addition,
the IRE resulted in marked influx of mixed inflammatory infiltrate into the treatment region, which was composed of neutrophils, macrophages, and primarily CD3⫹lymphocytes
Volumetric tumor regression occurred for several weeks after IRE, as necrotic tissue was resorbed by the immune system and local tissue healing and remodeling occurred. At the 6-month recheck, the patient was in complete remission according to clinical and CT examinations.
Purpose. Examination of the potential of electroporation therapy (EPT) in a patient with metastatic soft tissue sarcoma.
Patient. A 24-year-old male who underwent extensive resection and postoperative radiotherapy for a malignant peripheral nerve sheath tumor in the right infratemporal fossa with intracranial extension and invasion of the maxillary sinus and mandible had a recurrence in the scar of his craniotomy for which he was initially treated with doxorubicin. After discontinuation of doxorubicin he developed a metastatic mass at the same site for which he was treated with electroporation therapy.
Method. The subcutaneous metastasis was infiltrated with bleomycin and electroporated.
Results. Gradually the tumor became increasingly necrotic and demarcated from surrounding tissue. After 10 weeks no tumor was seen anymore. The wound healed secondarily.
Discussion. Intralesional bleomycin followed by EPT is potentially effective, well tolerated, and easy to perform in well accessible soft tissue sarcoma sites.
What is a mechanism behind of complete tumor suicide that was triggered with electroporation? Same behavior could be observed in some radiotherapy treatments.