Systematic Resection of the Visible Scar After Incomplete Endoscopic Resection of Rectal Neuroendocrine Tumors.

INTRODUCTION: When initial resection of rectal neuroendocrine tumors (r-NETs) is not R0, persistence of local residue could lead to disease recurrence. This study aimed to evaluate the interest of systematic resection of non-R0 r-NET scars. METHODS: Retrospective analysis of all the consecutive endoscopic revisions and resections of the scar after non-R0 resections of r-NETs. RESULTS: A total of 100 patients were included. Salvage endoscopic procedure using endoscopic submucosal dissection or endoscopic full-thickness resection showed an R0 rate of near 100%. Residual r-NET was found in 43% of cases. DISCUSSION: In case of non-R0 resected r-NET, systematic scar resection by endoscopic full-thickness resection or endoscopic submucosal dissection seems necessary.

Post first-line dacarbazine or temozolomide in neuroendocrine carcinoma.

OBJECTIVE: First-line chemotherapy in metastatic neuroendocrine carcinomas (NECs) is based on etoposide and platinum. However, there is no standard concerning second-line treatment. The objective of this study was to evaluate efficacy and tolerance of dacarbazine or temozolomide in metastatic digestive NEC as post first-line treatment. MATERIAL AND METHODS: This study included patients with a metastatic NEC of digestive or unknown primary site. All patients received platinum-etoposide as first-line chemotherapy. Primary endpoint was progression-free survival (PFS). Secondary endpoints were clinical/morphological responses, toxicity, and overall survival (OS). RESULTS: Twenty-seven patients were included: 17 received dacarbazine and 10 temozolomide as post-first line treatments. Median PFS was 3.0 (95%CI (2.2;3.7)) months. There was no significant difference between dacarbazine and temozolomide on PFS. Clinical and morphological responses were found in 12 and 9 patients, respectively. Median OS was 7.2 (95%CI (2.2;12.2)) months. The toxicity profile was that expected with such treatments. CONCLUSION: LV5FU2-dacarbazine or temozolomide-capecitabine chemotherapies allow a temporary clinical response for almost half of patients and/or a morphological response for a third of patients.

Endoscopic management of 345 small rectal neuroendocrine tumours: A national study from the French group of endocrine tumours (GTE).

Introduction: Small rectal neuroendocrine tumours are good candidates for endoscopic resection provided that complete pathological resection (R0) is obtained and their risk of metastatic progression is low. We conducted a large multicentre nationwide study to evaluate the outcomes of the management of non-metastatic rectal neuroendocrine tumours ≤2 cm diagnosed endoscopically. Patients and methods: The medical records, the endoscopic and pathological findings of patients with non-metastatic rectal neuroendocrine tumours ≤2 cm managed from January 2000-June 2018 in 16 French hospitals, were retrospectively analysed. The primary objective was to describe the proportion of R0 endoscopic resections. Results: A total of 329 patients with 345 rectal neuroendocrine tumours were included, 330 (96%) tumours were managed by local treatments: 287 by endoscopy only and 43 by endoscopy followed by transanal endoscopic microsurgery. The final endoscopic R0 rate was 134/345 (39%), which improved from the first endoscopy (54/225, 24%), to the second (60/100, 60%) and the third endoscopy (20/26, 77%). R0 was associated with endoscopic technique (90% for advanced techniques, 40% for mucosectomy and 17% for polypectomy), but not with tumour or patient characteristics. Twenty patients had metastatic disease, which was associated with tumour size ≥10 mm (odds ratio: 9.1, 95% confidence interval (3.5-23.5)), tumour grade G2-G3 (odds ratio: 4.2, (1.5-11.7)), the presence of muscular (odds ratio: ∞, (11.9-∞)) and lymphovascular invasion (odds ratio: 57.2, (5.6-578.9)). Conclusions: The resection of small rectal neuroendocrine tumours often requires multiple procedures. Training of endoscopists is necessary in order to better recognise these tumours and to perform the appropriate resection technique.

Endoscopic, transanal, laparoscopic, and transabdominal management of rectal neuroendocrine tumors.

Rectal neuroendocrine tumors (RNET) are rare tumors but their prevalence is constantly increasing due to a prolonged survival and rising incidence related to a growing number of colonoscopies and improved knowledge. Their main prognostic determinant is tumor stage. While most RNET are localized, their management should be tailored depending on the presence or absence of the factors predictive of lymph-node metastases including tumor size, endoscopic aspect, T stage, grade and lymphovascular invasion. Endoscopic ultrasonography is the most relevant technique for locoregional assessment. Low-risk RNET can be treated using advanced endoscopic resection techniques or transanal endoscopic microsurgery, in expert centers because they require technicity and experience. Conversely, radical surgery with lymphadenectomy should be proposed in the presence of any pejorative factor. The long-term evolution of RNET remains to be specified, and prospective studies should be conducted in order to determine the relevance of the current management strategies.