Objective: To provide a real-world, population-based assessment of the incidence and outcomes of neuroendocrine neoplasms (NENs) of unknown primary. Methods: Surveillance, Epidemiology and End Results (SEER) database was accessed and cases with NENs of unknown primary were reviewed. Rates of NENs diagnosis 1975-2017 according to primary tumor site were also reviewed. Survival outcomes of patients with NENs of unknown primary compared to metastatic NENs with known primary were determined through Kaplan-Meier estimates and multivariable Cox regression analysis. Overall and cancer-specific survival analyses were stratified by primary site and histology (neuroendocrine tumor versus neuroendocrine carcinoma). Results: A total of 3,550 cases (7%) were diagnosed with NENs of unknown primary within the study duration. The annual percent change for NENs of unknown primary was 3.4 (95% CI: 2.6- 4.2). Within the cohort of metastatic neuroendocrine tumor patients (carcinoid tumor histology), the following factors were associated with a lower risk of death; younger age (HR: 0.477; 95% CI: 0.443-0.513), female sex (HR: 0.922; 95% CI: 0.860-0.989), and small intestinal primary (HR for unknown primary versus small intestinal primary: 1.532; 95% CI: 1.408-1.668). Within the cohort of metastatic neuroendocrine carcinoma, the following factors were associated with a lower risk of death in this cohort; younger age (HR: 0.646; 95% CI: 0.612-0.681), female sex (HR: 0.843; 95% CI: 0.801-0.888), and small intestinal primary (HR for unknown primary versus small intestinal primary: 2.961; 95% CI: 2.586-3.391). Conclusions: The diagnosis of NENs of unknown primary has increased across the past four decades. Outcomes of individuals with metastatic small intestinal NENs seem to be better than those with metastatic NENs of unknown primary, both neuroendocrine tumors, and carcinomas.


中文翻译：

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对未知原发性神经内分泌肿瘤发病率和结果的真实世界、基于人群的研究。

目的：对未知原发性神经内分泌肿瘤 (NENs) 的发病率和结局提供真实的、基于人群的评估。方法：访问监测、流行病学和最终结果 (SEER) 数据库，并对原发性未知的 NEN 病例进行回顾。还回顾了 1975-2017 年根据原发肿瘤部位的 NEN 诊断率。通过 Kaplan-Meier 估计和多变量 Cox 回归分析确定原发性未知 NEN 患者与已知原发性转移性 NEN 患者的生存结果。总体和癌症特异性生存分析按原发部位和组织学（神经内分泌肿瘤与神经内分泌癌）进行分层。结果：在研究期间，共有 3,550 例 (7%) 被诊断为原发性不明的 NEN。未知原发性 NEN 的年度百分比变化为 3.4（95% CI：2.6-4.2）。在转移性神经内分泌肿瘤患者（类癌肿瘤组织学）队列中，以下因素与较低的死亡风险相关；年龄较小（HR：0.477；95% CI：0.443-0.513）、女性（HR：0.922；95% CI：0.860-0.989）和小肠原发性（未知原发性与小肠原发性的 HR：1.532；95% CI：1.408-1.668）。在转移性神经内分泌癌队列中，以下因素与该队列中较低的死亡风险相关；年龄较小（HR：0.646；95% CI：0.612-0.681）、女性（HR：0.843；95% CI：0.801-0.888）和小肠原发性（未知原发性与小肠原发性的 HR：2.961；95% CI：2.586-3.391）。结论：在过去的四年中，对原发性不明的 NEN 的诊断有所增加。转移性小肠 NENs 个体的结果似乎优于原发性不明的转移性 NENs 患者，包括神经内分泌肿瘤和癌。