Department of Surgery, City of Hope National Medical Center, Duarte, CA, USA.
Ann Surg Oncol. 2019 Nov;26(12):4008-4015. doi: 10.1245/s10434-019-07637-9. Epub 2019 Jul 29.
Appendiceal neuroendocrine tumors (NETs) are incidentally found in up to 1% of appendectomy specimens. The association of lymphovascular invasion (LVI) with risk of regional lymph node involvement is unclear.
From the National Cancer Database, 2004-2015, this study identified patients who had tumors 2 cm or smaller with one or more lymph nodes (LNs) pathologically evaluated. The histology was defined as typical, goblet cell, or composite NETs. Patient demographics, tumor characteristics, and treatment variables were analyzed.
The histologies for the 1767 identified patients were typical (n = 921, 52.1%), goblet cell (n = 556, 31.5%), and composite (n = 290, 16.4%). The tumor grades were low (70.4%), moderate (18.6%), and high (11%). The overall LN positivity was 17%. Of 1052 tumors evaluated, 215 (20.4%) had LVI. Overall survival decreased with node involvement (mean 84 vs. 124 months; p < 0.0001, log-rank). In the multivariate logistic regression analysis, LVI was independently associated with node involvement [odds ratio (OR) 5.0; p < 0.0001] after adjustment for patient age and tumor histologic subtype, size, and grade. In the subset analysis of typical NETs, tumor size of 1-2 cm (ref. < 1 cm; OR 5.5; p < 0.001) and presence of LVI (ref. absence of LVI; OR 4.8; p < 0.0001) were the only factors independently associated with LN involvement.
Node involvement is associated with worse overall survival in appendiceal NETs. The presence of LVI was strongly associated with lymph node involvement. An appendectomy specimen showing LVI should prompt strong consideration of colectomy with regional lymphadenectomy even for small, typical appendiceal NETs.
阑尾神经内分泌肿瘤（NET）在阑尾切除术标本中约有 1%为偶发发现。淋巴血管侵犯（LVI）与区域淋巴结受累风险的关联尚不清楚。
本研究从国家癌症数据库（2004-2015 年）中确定了肿瘤直径为 2cm 或更小且有一个或多个淋巴结（LNs）经病理评估的患者。组织学定义为典型、杯状细胞或复合 NETs。分析了患者人口统计学、肿瘤特征和治疗变量。
1767 例患者的组织学为典型（n=921，52.1%）、杯状细胞（n=556，31.5%）和复合（n=290，16.4%）。肿瘤分级为低（70.4%）、中（18.6%）和高（11%）。总体 LN 阳性率为 17%。在 1052 例评估的肿瘤中，有 215 例（20.4%）存在 LVI。有淋巴结受累的患者总生存率降低（平均 84 个月 vs. 124 个月；p<0.0001，对数秩检验）。在多变量逻辑回归分析中，调整患者年龄和肿瘤组织学亚型、大小和分级后，LVI 与淋巴结受累独立相关（比值比 [OR] 5.0；p<0.0001）。在典型 NET 亚组分析中，肿瘤大小为 1-2cm（参考<1cm；OR 5.5；p<0.001）和存在 LVI（参考不存在 LVI；OR 4.8；p<0.0001）是与 LN 受累独立相关的唯一因素。
淋巴结受累与阑尾 NET 的总体生存率较差相关。LVI 的存在与淋巴结受累密切相关。阑尾切除标本中出现 LVI 时，即使对于小的典型阑尾 NET，也应强烈考虑行结肠切除术加区域淋巴结切除术。
