Endoscopic ultrasound-guided radiofrequency ablation for management of gastric gastrointestinal stromal tumor

A 56-year-old man presented with abdominal pain and dyspepsia. On upper digestive endoscopy, a submucosal lesion was found in the distal gastric lesser curvature, but no conclusive diagnosis could be achieved with conventional biopsies. Endoscopic ultrasound (EUS) showed a 12 × 7 mm well-defined, homogeneous, hypoechoic nodule without signs of infiltration into the muscularis propria, suggestive of benign gastrointestinal stromal tumor (GIST) ([Fig. 1]). Fine-needle aspiration with a 22-gauge needle (Expect; Boston Scientific, Marlborough, Massachusetts, USA) was performed, confirming a low risk GIST. Histopathological examination revealed a GIST presenting less than 5 mitoses per high-power field.

Fig. 1 Endoscopic ultrasound image of gastrointestinal stromal tumor. a Radial view. b Linear view.

The patient rejected surgical treatment, so we proposed EUS-guided radiofrequency ablation (RFA) ([Video 1]). We punctured the lesion with an 18-gauge EUS-RFA electrode needle connected to a radiofrequency generator (VIVA-RF generator; STARme, Seoul, South Korea), and applied ablative radiofrequency four times (50 W for 10 seconds).

Video 1 Diagnosis of benign gastrointestinal stromal tumor (GIST) and treatment with endoscopic ultrasound (EUS)-guided radiofrequency ablation (RFA). EUS follow-up was performed after 4 weeks, and showed a slight mural thickening of the muscularis propria and submucosal layers, while the lesion itself could not be identified. A second EUS 6 months later confirmed eradication of the lesion, and showed a well-preserved layer pattern.

EUS follow-up was performed after 4 weeks, and showed a slight mural thickening of the muscularis propria and submucosal layers; the lesion itself could not be identified ([Fig. 2]). A fine-needle biopsy with 22-gauge histological needle (Acquire; Boston Scientific) was performed and confirmed the absence of GIST-type mesenchymal structures. A second EUS 6 months later confirmed eradication of the lesion, and showed a well-preserved layer pattern ([Fig. 3]).

Fig. 2 Endoscopic ultrasound image of gastrointestinal stromal tumor after treatment with ablative radiofrequency. a Radial view. b Linear view.

Fig. 3 Endoscopic ultrasound 6 months later confirmed eradication of the lesion, and showed a preserved layer pattern.

Guidelines recommend radical surgical resection with a clear margin (R0) as the gold standard for localized primary GIST [1]. Although endoscopic resection of GISTs has been reported [2], it is not supported by current guidelines because of the low rate of successful R0 resections achieved [1]. RFA uses high frequency alternating current applied via an electrode to generate localized areas of coagulative necrosis and tissue desiccation [3] [4]. Although it is usually applied percutaneously or laparoscopically, successful outcomes of EUS-guided RFA using an 18-gauge needle for benign and malignant pancreatic lesions have been reported recently [5]. To our knowledge, this is the first report of a successful ablative radiofrequency therapy of a gastric GIST.

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• References

• 1 Poveda A, García del Muro X, López-Guerrero JA. et al. GEIS guidelines for gastrointestinal sarcomas (GIST). Cancer Treat Rev 2017; 55: 107-119
• 2 Mosquera-Klinger G, de la Serna Higuera C, Pérez-Miranda M. Treatment of gastric GIST using endoscopic techniques combined with the application of endoloop and intralesional cyanoacrylate in a non-surgical patient. Rev Esp Enferm Dig 2018; 110: 825
• 3 Song TJ, Seo DW, Lakhtakia S. et al. Initial experience of EUS-guided radiofrequency ablation of unresectable pancreatic cancer. Gastrointest Endosc 2016; 83: 440-443
• 4 Yoon IS, Shin JH, Han K. et al. Ultrasound-guided intraoperative radiofrequency ablation and surgical resection for liver metastasis from malignant gastrointestinal stromal tumors. Korean J Radiol 2018; 19: 54-62
• 5 Crinò SF, D’Onofrio M, Bernardoni L. et al. EUS-guided radiofrequency ablation (EUS-RFA) of solid pancreatic neoplasm using an 18-gauge needle electrode: feasibility, safety, and technical success. J Gastrointest Liver Dis 2018; 27: 67-72