In select patients with pancreatic neuroendocrine tumors, endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is a viable treatment modality that is relatively safe and effective, according to study results published by The Journal of Clinical Endocrinology & Metabolism.
In this retrospective cohort study, investigators analyzed data from patients diagnosed with pancreatic neuroendocrine neoplasms who had been selected for EUS-RFA treatment at 2 tertiary referral centers in Israel between March 2017 and October 2018 (N = 18). Inclusion criteria included the following: histopathologic diagnosis of well-differentiated pancreatic neuroendocrine neoplasm, insulinoma, nonfunctional pancreatic neuroendocrine tumor, localized tumor, minimally advanced pancreatic neuroendocrine tumor, ineligibility for or refusal of surgery, informed nonconsent for initially recommended active surveillance, and a life expectancy >24 months. Complete clinical histories and physical examination, routine laboratory tests, and disease-related markers were included in the workup for each patient. Imaging studies and contrast-enhanced spiral computed tomography were also performed. EUS-RFA procedures were performed endoscopically on an inpatient basis.
Of 18 patients in the study (44% women; mean age at diagnosis, 60.4 years; age range, 28-82 years), 7 patients had insulinoma and 11 patients had nonfunctional pancreatic neuroendocrine tumors. All lesions were well-differentiated Grade 1 tumors. In the patients with nonfunctional pancreatic neuroendocrine tumors, 9 patients had a sporadic tumor and 2 patients had multiple endocrine neoplasia type 1 syndrome association.
Localizations of the lesions by contrast-enhanced computed tomography and EUS were successful in every case. In total, 27 lesions with a mean size of 14.3 ± 7.3 mm were treated with EUS-RFA. In the EUS-RFA procedures, typical post-ablative changes on surveillance imaging were achieved for 26 out of 27 lesions. Radiologic complete response was reported in 17 or 18 patients. All 7 patients with insulinoma had complete relief of hypoglycemia-related symptoms and normalization of glucose levels.
There were no major adverse events within 48 hours after the procedure and no clinically significant recurrences during the mean follow-up of 8.7 ± 4.6 months.
The study was limited by its retrospective, heterogeneous cohort design and relatively short follow-up time.
These findings demonstrate that EUS-RFA is a “relatively safe and effective treatment modality in selected patients with [pancreatic neuroendocrine tumors].” Future studies implementing prospective, multicenter designs including a larger number of patients with pancreatic neuroendocrine tumors are recommended to confirm the results of this study. “[U]ntil such trials will be available, clinicians who manage these patients will [likely] have to rely on personal experience and data from retrospective studies.”
Oleinikov K, Dancour A, Epshtein J, et al. Endoscopic ultrasound-guided radiofrequency ablation: a new therapeutic approach for pancreatic neuroendocrine tumors [published online April 9, 2019]. J Clin Endocrinol Metab. doi:10.1210/jc.2019-00282