Abstract：
OBJECTIVE: This study aimed to identify cases in which lateral lymph node (LLN) dissection (LLND) can be excluded by clarifying preoperative factors, including an evaluation of the middle rectal artery (MRA), associated with LLN metastasis.
METHODS: Fifty-five consecutive patients who underwent preoperative positron emission tomography-computed tomography (PET/CT) and total mesorectal excision with LLND for rectal cancer were included. We retrospectively investigated the preoperative clinical factors associated with pathological LLN (pLLN) metastasis. We analyzed the regions of pLLN metastasis using MRA.
RESULTS: pLLN metastasis occurred in 13 (23.6%) patients. According to a multivariate analysis, clinical LLN (cLLN) metastasis based on short-axis size and LLN status based on PET/CT were independent preoperative factors of pLLN metastasis. The negative predictive value (NPV) was high (97.1%) in patients evaluated as negative based on PET/CT and cLLN short-axis size. MRA was detected in 24 patients (43.6%) using contrast-enhanced CT, and there was a significant relationship between pLLN metastasis and the presence of MRA. pLLN metastasis in the internal iliac region but not in the obturator region was significantly correlated with the presence of MRA.
CONCLUSIONS: Combined cLLN metastasis based on short-axis size and PET/CT showed a higher NPV, suggesting this to be a useful method for identifying cases in which LLND can be excluded.
METHODS: Fifty-five consecutive patients who underwent preoperative positron emission tomography-computed tomography (PET/CT) and total mesorectal excision with LLND for rectal cancer were included. We retrospectively investigated the preoperative clinical factors associated with pathological LLN (pLLN) metastasis. We analyzed the regions of pLLN metastasis using MRA.
RESULTS: pLLN metastasis occurred in 13 (23.6%) patients. According to a multivariate analysis, clinical LLN (cLLN) metastasis based on short-axis size and LLN status based on PET/CT were independent preoperative factors of pLLN metastasis. The negative predictive value (NPV) was high (97.1%) in patients evaluated as negative based on PET/CT and cLLN short-axis size. MRA was detected in 24 patients (43.6%) using contrast-enhanced CT, and there was a significant relationship between pLLN metastasis and the presence of MRA. pLLN metastasis in the internal iliac region but not in the obturator region was significantly correlated with the presence of MRA.
CONCLUSIONS: Combined cLLN metastasis based on short-axis size and PET/CT showed a higher NPV, suggesting this to be a useful method for identifying cases in which LLND can be excluded.
摘要：
目的：本研究旨在通过明确术前因素来确定可以排除外侧淋巴结（LLN）清扫（LLND）的病例。包括对直肠中动脉（MRA）的评估，与LLN转移相关。
方法：纳入了55例连续的患者，这些患者接受了术前正电子发射断层扫描-计算机断层扫描（PET/CT）和全直肠系膜切除联合LLND治疗直肠癌。我们回顾性调查了与病理性LLN（pLLN）转移相关的术前临床因素。我们使用MRA分析了pLLN转移的区域。
结果：13例（23.6%）患者发生pLLN转移。根据多变量分析，基于短轴大小的临床LLN（cLLN）转移和基于PET/CT的LLN状态是pLLN转移的独立术前因素。根据PET/CT和cLLN短轴大小评估为阴性的患者的阴性预测值（NPV）较高（97.1％）。使用对比增强CT在24例患者中检测到MRA（43.6％），pLLN转移与MRA的存在之间存在显着关系。pLLN在内部区域而不是在闭塞区域的转移与MRA的存在显着相关。
结论：基于短轴大小和PET/CT的联合cLLN转移显示出较高的NPV，这表明这是一种识别可以排除LLND的病例的有用方法。
方法：纳入了55例连续的患者，这些患者接受了术前正电子发射断层扫描-计算机断层扫描（PET/CT）和全直肠系膜切除联合LLND治疗直肠癌。我们回顾性调查了与病理性LLN（pLLN）转移相关的术前临床因素。我们使用MRA分析了pLLN转移的区域。
结果：13例（23.6%）患者发生pLLN转移。根据多变量分析，基于短轴大小的临床LLN（cLLN）转移和基于PET/CT的LLN状态是pLLN转移的独立术前因素。根据PET/CT和cLLN短轴大小评估为阴性的患者的阴性预测值（NPV）较高（97.1％）。使用对比增强CT在24例患者中检测到MRA（43.6％），pLLN转移与MRA的存在之间存在显着关系。pLLN在内部区域而不是在闭塞区域的转移与MRA的存在显着相关。
结论：基于短轴大小和PET/CT的联合cLLN转移显示出较高的NPV，这表明这是一种识别可以排除LLND的病例的有用方法。
