{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T20:41:15Z","timestamp":1790800875900,"version":"4.1.0"},"reference-count":12,"publisher":"Harborside Press, LLC","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,1]]},"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Neuroendocrine tumors (NETs) of the appendix are typically detected incidentally during appendectomy. Recent studies reported no metachronous metastases among patients with primary tumors &lt;2 cm, regardless of lymph node status or referral for completion hemicolectomy. However, questions persist regarding the possibility of metastases developing decades after surgical resection, particularly because appendiceal NETs are frequently diagnosed in young adults and children. Therefore, we sought to evaluate patients with metastatic appendiceal NETs to assess whether any had been diagnosed previously with an early-stage appendiceal NET. <jats:bold>Methods:<\/jats:bold> We analyzed a large institutional neuroendocrine tumor database to identify appendiceal NETs of all stages and ascertain whether any patients with localized tumors developed metastases and whether any with metastatic disease had initially presented with an early-stage tumor. <jats:bold>Results:<\/jats:bold> Of 3,795 patients with gastroenteropancreatic (GEP) NETs seen in an oncologic NET clinic between January 2008 and August 2023, 124 presented with appendiceal NETs. Of these, only 10 (&lt;0.3% of the total GEP-NET population) had stage IV disease, 8 of whom were diagnosed synchronously at the time of initial diagnosis. Two patients with metastatic disease had reportedly undergone surgical resection for a primary appendiceal NET approximately 20 years before the diagnosis of metastatic disease, but medical records were not available to confirm an appendiceal primary. <jats:bold>Conclusions:<\/jats:bold> Stage IV appendiceal NETs are exceptionally rare, and distant metastases are synchronous in nearly all cases. The risk of metastatic spread after resection of local appendiceal NETs is negligible. Patients with tumors &lt;2 cm should not be managed with completion right hemicolectomy, and the role of this operation for larger tumors is questionable. Postoperative surveillance is unlikely to be of benefit.<\/jats:p>","DOI":"10.6004\/jnccn.2024.7069","type":"journal-article","created":{"date-parts":[[2024,12,20]],"date-time":"2024-12-20T19:03:23Z","timestamp":1734721403000},"source":"Crossref","is-referenced-by-count":3,"title":["Do Appendiceal Neuroendocrine Tumors Metastasize Post Appendectomy or Right Hemicolectomy?"],"prefix":"10.6004","volume":"23","author":[{"given":"Taymeyah","family":"Al-Toubah","sequence":"first","affiliation":[{"name":"Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mintallah","family":"Haider","sequence":"additional","affiliation":[{"name":"Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eleonora","family":"Pelle","sequence":"additional","affiliation":[{"name":"Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Grazia","family":"Maratta","sequence":"additional","affiliation":[{"name":"Fondazione Policlinico Agostino Gemelli, IRCCS, Universita Cattolica del Sacro Cuore, Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan","family":"Strosberg","sequence":"additional","affiliation":[{"name":"Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"4047","reference":[{"key":"B1","series-title":"Neuroendocrinology","first-page":"242","article-title":"Surgical management of patients with neuroendocrine neoplasms of the appendix: appendectomy or more","volume":"106","author":"Pawa N","year":"2018","unstructured":"Pawa N, Clift AK, Osmani H,  Surgical management of patients with neuroendocrine neoplasms of the appendix: appendectomy or more. Neuroendocrinology 2018;106:242\u2013251."},{"key":"B2","series-title":"Am J Gastroenterol","first-page":"422","article-title":"A retrospective analysis of 1570 appendiceal carcinoids","volume":"93","author":"Sandor A","year":"1998","unstructured":"Sandor A, Modlin IM. A retrospective analysis of 1570 appendiceal carcinoids. Am J Gastroenterol 1998;93:422\u2013428."},{"key":"B3","series-title":"N Engl J Med","first-page":"1699","article-title":"Carcinoid tumor of the appendix: treatment and prognosis","volume":"317","author":"Moertel CG","year":"1987","unstructured":"Moertel CG, Weiland LH, Nagorney DM, Dockerty MB. Carcinoid tumor of the appendix: treatment and prognosis. 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Ann Surg 2020;271:527\u2013533."},{"key":"B5","series-title":"Endocrine","first-page":"20","article-title":"The risk of lymph node metastases and their impact on survival in patients with appendiceal neuroendocrine neoplasms: a systematic review and meta-analysis of adult and paediatric patients","volume":"67","author":"Daskalakis K","year":"2020","unstructured":"Daskalakis K, Alexandraki K, Kassi E,  The risk of lymph node metastases and their impact on survival in patients with appendiceal neuroendocrine neoplasms: a systematic review and meta-analysis of adult and paediatric patients. Endocrine 2020;67:20\u201334."},{"key":"B6","series-title":"Endocrine","first-page":"178","article-title":"The effect of prophylactic surgery in survival and HRQoL in appendiceal NEN","volume":"70","author":"Alexandraki KI","year":"2020","unstructured":"Alexandraki KI, Kaltsas G, Grozinsky-Glasberg S,  The effect of prophylactic surgery in survival and HRQoL in appendiceal NEN. Endocrine 2020;70:178\u2013186."},{"key":"B7","series-title":"Neuroendocrinology","first-page":"144","article-title":"ENETS consensus guidelines for neuroendocrine neoplasms of the appendix (excluding goblet cell carcinomas)","volume":"103","author":"Pape UF","year":"2016","unstructured":"Pape UF, Niederle B, Costa F,  ENETS consensus guidelines for neuroendocrine neoplasms of the appendix (excluding goblet cell carcinomas). Neuroendocrinology 2016;103:144\u2013152."},{"key":"B8","series-title":"Pancreas","first-page":"753","article-title":"The NANETS consensus guideline for the diagnosis and management of neuroendocrine tumors: well-differentiated neuroendocrine tumors of the jejunum, ileum, appendix, and cecum","volume":"39","author":"Boudreaux JP","year":"2010","unstructured":"Boudreaux JP, Klimstra DS, Hassan MM,  The NANETS consensus guideline for the diagnosis and management of neuroendocrine tumors: well-differentiated neuroendocrine tumors of the jejunum, ileum, appendix, and cecum. Pancreas 2010;39:753\u2013766."},{"key":"B9","article-title":"NCCN Clinical Practice Guidelines in Oncology: Neuroendocrine and Adrenal Tumors. Version 2.2024","author":"Bergsland E","unstructured":"Bergsland E, Rose JB, Benson AB III,  NCCN Clinical Practice Guidelines in Oncology: Neuroendocrine and Adrenal Tumors. Version 2.2024. Accessed October 1, 2024. To view the most recent version, visit https:\/\/www.nccn.org\/"},{"key":"B10","series-title":"Lancet Oncol","first-page":"187","article-title":"Hemicolectomy versus appendectomy for patients with appendiceal neuroendocrine tumours 1-2 cm in size: a retrospective, Europe-wide, pooled cohort study","volume":"24","author":"Nesti C","year":"2023","unstructured":"Nesti C, Br\u00e4utigam K, Benavent M,  Hemicolectomy versus appendectomy for patients with appendiceal neuroendocrine tumours 1-2 cm in size: a retrospective, Europe-wide, pooled cohort study. Lancet Oncol 2023;24:187\u2013194."},{"key":"B11","series-title":"Lancet Oncol","first-page":"e189","article-title":"Omitting hemicolectomy for patients with appendiceal neuroendocrine tumours of 1-2 cm","volume":"24","author":"Halfdanarson TR","year":"2023","unstructured":"Halfdanarson TR, Grotz TE, Gudmundsdottir H,  Omitting hemicolectomy for patients with appendiceal neuroendocrine tumours of 1-2 cm. Lancet Oncol 2023;24:e189."},{"key":"B12","series-title":"Pediatr Blood Cancer","first-page":"e27069","article-title":"Systematic review and meta-analysis of appendiceal carcinoid tumors in children","volume":"65","author":"Njere I","year":"2018","unstructured":"Njere I, Smith LL, Thurairasa D,  Systematic review and meta-analysis of appendiceal carcinoid tumors in children. Pediatr Blood Cancer 2018;65:e27069."}],"container-title":["Journal of the National Comprehensive Cancer Network"],"original-title":[],"link":[{"URL":"https:\/\/jnccn.org\/view\/journals\/jnccn\/23\/1\/article-e247069.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/jnccn.org\/downloadpdf\/journals\/jnccn\/23\/1\/article-e247069.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/jnccn.org\/downloadpdf\/journals\/jnccn\/23\/1\/article-e247069.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,1,15]],"date-time":"2025-01-15T13:55:27Z","timestamp":1736949327000},"score":1,"resource":{"primary":{"URL":"https:\/\/jnccn.org\/view\/journals\/jnccn\/23\/1\/article-e247069.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1]]},"references-count":12,"journal-issue":{"issue":"1"},"URL":"https:\/\/doi.org\/10.6004\/jnccn.2024.7069","relation":{},"ISSN":["1540-1405","1540-1413"],"issn-type":[{"value":"1540-1405","type":"print"},{"value":"1540-1413","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1]]}}}