Al-Toubah Taymeyah, Haider Mintallah, Pelle Eleonora, Maratta Maria Grazia, Strosberg Jonathan
Department of Gastrointestinal Oncology, Moffitt Cancer Center, Tampa, FL.
Fondazione Policlinico Agostino Gemelli, IRCCS, Universita Cattolica del Sacro Cuore, Rome, Italy.
J Natl Compr Canc Netw. 2024 Dec 20;23(1):e247069. doi: 10.6004/jnccn.2024.7069.
Neuroendocrine tumors (NETs) of the appendix are typically detected incidentally during appendectomy. Recent studies reported no metachronous metastases among patients with primary tumors <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.
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.
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 (<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.
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 <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.
阑尾神经内分泌肿瘤（NETs）通常在阑尾切除术中偶然发现。最近的研究报告称，原发性肿瘤<2 cm的患者中无异时性转移，无论淋巴结状态如何或是否因行根治性半结肠切除术而转诊。然而，关于手术切除数十年后发生转移的可能性仍存在疑问，特别是因为阑尾NETs在年轻人和儿童中经常被诊断出来。因此，我们试图评估转移性阑尾NETs患者，以确定是否有患者之前被诊断为早期阑尾NET。
我们分析了一个大型机构神经内分泌肿瘤数据库，以识别所有阶段的阑尾NETs，并确定是否有局部肿瘤患者发生转移，以及是否有转移性疾病患者最初表现为早期肿瘤。
在2008年1月至2023年8月期间在肿瘤NET诊所就诊的3795例胃肠胰（GEP）NETs患者中，124例表现为阑尾NETs。其中，只有10例（占GEP-NET总人群的<0.3%）患有IV期疾病，其中8例在初次诊断时为同时性诊断。据报道，2例转移性疾病患者在诊断转移性疾病前约20年曾因原发性阑尾NET接受手术切除，但无法获取病历以证实阑尾原发性。
IV期阑尾NETs极为罕见，几乎所有病例的远处转移均为同时性。局部阑尾NETs切除术后发生转移扩散的风险可忽略不计。肿瘤<2 cm的患者不应行根治性右半结肠切除术，该手术对较大肿瘤的作用值得怀疑。术后监测不太可能有益。
