Kitagawa Yoshiyasu, Ikebe Dai, Suzuki Takuto, Hara Taro, Itami Makiko, Yamaguchi Taketo
Endoscopy Division, Chiba Cancer Center, Chiba, Japan.
Digestion. 2017;95(1):16-21. doi: 10.1159/000452357. Epub 2017 Jan 5.
Rectal neuroendocrine tumors (RNETs) have become common in recent years and are good candidates for endoscopic resection (ER). To achieve clear resection margins, more advanced techniques such as endoscopic submucosal dissection, endoscopic submucosal resection with a ligation device, and cap-assisted endoscopic mucosal resection are available for ER. After ER, lymphovascular invasion (LVI) is regarded as an important predictor of nodal metastasis. Previous studies have shown that small RNETs with LVI were uncommon (0-8.3%). However, using immunohistochemical analysis, a recent study revealed the frequent occurrence of LVI in small RNETs in a systematic manner (46.7%). There is a possibility that the actual detection rate of LVI in small RNETs is not always evaluated accurately because of the limited detection sensitivity of conventional hematoxylin-eosin staining. In addition, the correlation between LVI detected using immunohistochemical analysis and the development of metastasis remains unclear. Further prospective studies are required to clarify the role of LVI detected using immunohistochemical analysis.
直肠神经内分泌肿瘤（RNETs）近年来变得常见，是内镜切除（ER）的良好适应证。为实现切缘阴性，有更多先进技术可用于ER，如内镜黏膜下剥离术、带结扎装置的内镜黏膜下切除术以及帽辅助内镜黏膜切除术。ER术后，脉管侵犯（LVI）被视为淋巴结转移的重要预测指标。既往研究表明，伴有LVI的小RNETs并不常见（0-8.3%）。然而，最近一项研究通过免疫组化分析系统地揭示了小RNETs中LVI的频繁发生（46.7%）。由于传统苏木精-伊红染色检测灵敏度有限，小RNETs中LVI的实际检出率可能并未总是得到准确评估。此外，免疫组化分析检测到的LVI与转移发生之间的相关性仍不清楚。需要进一步的前瞻性研究来阐明免疫组化分析检测到的LVI的作用。
