1H-5 Using Intraluminal Ultrasound for the Treatment of Esophageal Tumors: First Clinical Results

Esophageal tumors generally bear a poor prognosis. Radical surgery is generally the only curative method available but is not feasible in the majority of patients; palliative therapy with stent placement is generally performed. It has been demonstrated that high intensity ultrasound (HIU) can induce rapid, complete and well-defined coagulation necrosis. Thus, for the treatment of this cancer, we designed an ultrasound applicator that uses an intraluminal approach to fill up this therapeutic gap. Thermal ablation is performed with water-cooled ultrasound transducers operating at a frequency of 10 MHz. Elementary lesions extend from the transducer surface up to 10 mm in depth when applying an intensity of 14 W/cm2 for 10s. A lumen inside the therapy applicator provides path for an endoscopic ultrasound imaging probe. The rotation of the applicator around its axis enables treatment of sectorial or cylindrical volumes. This method is thus particularly suitable for esophageal tumors that may develop only on a portion of the esophageal circumference. Previous experiments were conducted from bench to in vivo studies on pig esophagi. In this study, four patients with esophageal tumors included in a pilot study have been treated using this ultrasound applicator. The treatment of esophageal tumors is done under fluoroscopic guidance and ultrasound imaging. Tumor response was observed in all cases. This clinical work demonstrated the efficacy of interstitial high intensity ultrasound therapy for local tumor destruction in the esophagus