Clinical impact of endoscopic ultrasonography for small rectal neuroendocrine tumors

Abstract

Background/Aims: Endoscopic ultrasonography (EUS) is helpful for evaluating the depth of tumor invasion and lymph node metastasis of rectal neuroendocrine tumors (NETs). The aim of this study was to clarify the clinical impact of EUS for rectal NETs less than 10 mm in diameter. Materials and Methods: : A total of 76 rectal NETs treated at our hospital between June 2006 and March 2013 were reviewed retrospectively. All lesions were analyzed with EUS to evaluate the depth of tumor invasion. The lesions were resected by endoscopic submucosal resection with band ligation (ESMR-L) or endoscopic submucosal dissection (ESD) and examined histologically. Results: Endoscopic ultrasonography findings showed that all lesions were confined to the submucosa and revealed no adjacent lymph node metastasis. Seventy-five of the 76 lesions were completely resected by ESMR-L. One lesion was resected by ESD and the resected deep margin of the lesion was histologically positive. Only one lesion exhibited lymphatic invasion. Conclusion: EUS may not be essential for diagnosis and treatment planning for rectal NETs less than 10 mm in size.

Endoscopic treatment of rectal neuroendocrine tumors in a 13-year retrospective single-center study. Are we following the guidelines?

“…[22][23][24] It suggests that a size of 10 mm (not 5 mm as in the ENETS guidelines) should be an indication for EUS. 24,25 Our findings are in line with those of other studies showing the metastatic potential of rNENs smaller than 10 mm, including studies dIsCussION Rectal NETs are subepithelial lesions with a metastatic potential, which have been recently detected with a growing frequency. 1 The key points in the management of those tumors include a proper diagnosis based on endoscopic features and removal of the tumor using EMR, ESD, TEM, or surgery (for lesions with risk features) to achieve R0 resection and prevent the development of metastases.…”

Is endoscopic ultrasonography essential for endoscopic resection of small rectal neuroendocrine tumors?

“…Several studies have examined the utility of EUS in the assessment and management of rectal NETs[2,5-8,21]. However, no previous studies have compared the size measurement of rectal NETs by endoscopy to either measurements by EUS or by histology; although, one study compared endoscopy and EUS in the evaluation of gastrointestinal subepithelial masses, including carcinoid tumor[22].…”

Risk Factors and Clinical Outcomes of 54 Cases of Rectal Neuroendocrine Tumors with Incomplete Resection: A Retrospective Single-Center Study

“…The vast majority of lesions are easily treated by endoscopy, with a high complete resection rate. However, many lesions with depressions, congestion, erosions, or ulcers on the surface are cancerous, so EUS should be performed for a differential diagnosis and a determination of depth of invasion, 12 , 13 and biopsy tissues should be taken. When a tumor is judged to be malignant, endoscopic treatment becomes invalid, and further examinations by abdominal CT, MRI, or positron emission tomography (PET)-CT are necessary.…”