Introduction
Neuroendocrine tumors (NETs) are heterogeneous neoplasms originating from neuroendocrine cells, predominantly located in the gastrointestinal tract and pancreas. While surgical resection remains the primary curative intervention, a significant number of patients are ineligible for surgery due to comorbidities or the anatomical positioning of the tumor. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as a minimally invasive alternative; however, the extant evidence is predominantly derived from small-scale case studies.
Aims & Methods
This multicenter study aims to comprehensively evaluate the efficacy, safety, and technical considerations of EUS-RFA in the management of NETs. A retrospective analysis was conducted on 45 patients with histologically confirmed neuroendocrine tumors (NETs) from five countries: Costa Rica, Egypt, India, Palestine, and Romania. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) was performed using a standardized 19-gauge RFA needle equipped with a 1 cm active-tip electrode. The primary outcomes assessed were treatment success, categorized as complete, partial, or failure. Secondary outcomes included the evaluation of complications and their correlations with tumor characteristics (such as grade, location, and histology), technical parameters (including power settings and ablation duration), and clinical factors. Statistical analyses were conducted using SPSS, employing Chi-square and Kruskal-Wallis tests.
Results
The cohort consisted of 53.3% females, with a mean age of 47.87 years. The overall complete ablation rate was 75.6%, with higher success rates observed for higher-grade tumors (G2/G3: 100% vs. G1: 80.8%). Tumor location significantly influenced outcomes, with pancreatic tail/neck lesions achieving 100% complete ablation compared to 58.8% for head lesions. Power settings of 35W, 40W, and 60W yielded 100% success, whereas 50W and 30W demonstrated lower efficacy (72.2% and 62.5%, respectively). Ablation duration tended to be longer in successful cases (mean 16.36 seconds) compared to failures (4.50 seconds). Insulinomas exhibited an 89.7% complete ablation rate, surpassing non-functioning NETs (50%). Complications were minimal, underscoring the procedure's safety.
Conclusion
Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) represents a safe and efficacious minimally invasive approach for the treatment of neuroendocrine tumors (NETs), particularly in patients who present a high surgical risk. The success of this technique is contingent upon the biological characteristics of the tumor, anatomical considerations, and the precision of the procedure. Future research should aim to standardize protocols, integrate advanced imaging techniques, and investigate combination therapies to further enhance this promising intervention.
References
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