Gallo C, Rossi RE, Cavalcoli F, Barbaro F, Boškoski I, Invernizzi P, Massironi S. Rectal neuroendocrine tumors: Current advances in management, treatment, and surveillance. World J Gastroenterol 2022; 28(11): 1123-1138 [PMID: 35431507 DOI: 10.3748/wjg.v28.i11.1123]
Corresponding Author of This Article
Sara Massironi, MD, PhD, Doctor, Division of Gastroenterology and Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, European Reference Network on Hepatological Diseases, San Gerardo Hospital, Via Pergolesi, 33, Monza 20900, Italy. s.massironi@asst-monza.it
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
Minireviews
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This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Gastroenterol. Mar 21, 2022; 28(11): 1123-1138 Published online Mar 21, 2022. doi: 10.3748/wjg.v28.i11.1123
Rectal neuroendocrine tumors: Current advances in management, treatment, and surveillance
Camilla Gallo, Roberta Elisa Rossi, Federica Cavalcoli, Federico Barbaro, Ivo Boškoski, Pietro Invernizzi, Sara Massironi
Camilla Gallo, Pietro Invernizzi, Sara Massironi, Division of Gastroenterology and Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, European Reference Network on Hepatological Diseases, San Gerardo Hospital, Monza 20900, Italy
Roberta Elisa Rossi, Division of HPB Surgery, Hepatology and Liver Transplantation, Department of Pathophysiology and Transplantation, University of Milan, ENETS Center of Excellence, Fondazione IRCCS Istituto Nazionale Tumori (INT, National Cancer Institute), Milan 20133, Italy
Federica Cavalcoli, Diagnostic and Therapeutic Endoscopy Unit, Fondazione IRCCS Istituto Nazionale Tumori, Milan 20133, Italy
Federico Barbaro, Ivo Boškoski, Digestive Endoscopy Unit, Università Cattolica del Sacro Cuore di Roma, Center for Endoscopic Research Therapeutics and Training, Fondazione Policlinico Universitario Agostino Gemelli IRCSS, Rome 00168, Italy
Author contributions: Massironi S, Gallo C, and Rossi RE conceived of the contents of the manuscript; Gallo C, Boskoski I, and Barbaro F developed the revision regarding the therapeutic options for r-NENs; Boskoski I and Barbaro F furnished the pictures; Massironi S developed the introduction, the surveillance paragraph, and the conclusive chapter; Rossi RE and Cavalcoli F developed the paragraph regarding the risk factors; Invernizzi P together with all authors, revised entirely the manuscript and contributed to its final aspect.
Conflict-of-interest statement: The authors declare no conflict of interests for this article.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Sara Massironi, MD, PhD, Doctor, Division of Gastroenterology and Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, European Reference Network on Hepatological Diseases, San Gerardo Hospital, Via Pergolesi, 33, Monza 20900, Italy. s.massironi@asst-monza.it
Received: October 15, 2021 Peer-review started: October 15, 2021 First decision: December 12, 2021 Revised: December 24, 2021 Accepted: February 20, 2022 Article in press: February 20, 2022 Published online: March 21, 2022 Processing time: 152 Days and 9 Hours
Abstract
Rectal neuroendocrine neoplasms (r-NENs) are considered among the most frequent digestive NENs, together with small bowel NENs. Their incidence has increased over the past few years, and this is probably due to the widespread use of endoscopic screening for colorectal cancer and the advanced endoscopic procedures available nowadays. According to the current European Neuroendocrine Tumor Society (ENETS) guidelines, well-differentiated r-NENs smaller than 10 mm should be endoscopically removed in view of their low risk of local and distant invasion. R-NENs larger than 20 mm are candidates for surgical resection because of their high risk of distant spreading and the involvement of the muscularis propria. There is an area of uncertainty regarding tumors between 10 and 20 mm, in which the metastatic risk is intermediate and the endoscopic treatment can be challenging. Once removed, the indications for surveillance are scarce and poorly codified by international guidelines, therefore in this paper, a possible algorithm is proposed.
Core Tip: Rectal neuroendocrine neoplasms (r-NENs) represent 1%-2% of all rectal tumors, but an increasing incidence rate has been recently reported. Up to 90% of r-NENs are < 10 mm in size, confined to the submucosa, and well-differentiated, so that the endoscopic resection represents their gold-standard therapy. Advanced metastatic NENs are usually poorly differentiated G3 carcinomas treated with chemotherapy, except for rare G1-G2 neoplasms, which can be targeted with less aggressive systemic options. Locally advanced r-NENs invading submucosal layers, with a ≥ 10 mm diameter, but still without distant metastases, represent the real therapeutic challenge among rectal tumors.
