这项工作的重点是开发和验证基于光谱CT的评分卡，以术前预测局部晚期胃癌（LAGC）中的神经周围侵袭（PNI）。本项工作前瞻性包括196个接受三重增强光谱CT扫描的LAGC患者（男性139名，女性57名，年龄为59.55±11.97岁）。根据病理学报告，将患者标记为神经周围侵袭（PNI）阳性或阴性，然后进一步分为初步组（n = 130）和验证组（n = 66）。提取临床病理信息、随访数据、碘浓度（IC）及动脉/静脉/延迟相（AP/VP/DP）的标准化IC值相对于主动脉（nICs）。比较神经周围侵袭（PNI）阳性和阴性组之间的临床病理特征和IC值。进行多变量 logistic 回归以筛选 PNI 的独立风险因素。然后，建立了一个评分卡，并通过 ROC 曲线确定了其能力。通过决策曲线分析评估其临床使用。通过对数秩生存分析探索了 PNI 和评分卡与患者生存率的相关性。Borrmann 分类、肿瘤厚度和 nICDP 是 PNI 的独立预测因子，用于建立评分卡。评分卡在初步研究和验证组中的AUC值分别为0.853（0.744-0.928）和0.782（0.701-0.850），高于任何其他参数（p<0.05）。PNI 和评分卡都与术后治疗规划有关。在初步组中，只有PNI与无病生存期的患者生存率相关（p<0.05）。本研究前瞻性建立了一种基于光谱CT的评分卡，能够有效预测手术前的PNI，并可能指导LAGC的术后治疗策略。提出的评分卡包括形态学特征和来自光谱CT的定量碘浓度值，具有预测LAGC的PNI的潜力，并指导术后治疗规划。延迟相的标准化碘浓度是最有价值的定量参数，提示了胃CT中延迟增强的重要性。©2023年作者，独家许可欧洲放射学会。

This work focused on developing and validating the spectral CT-based nomogram to preoperatively predict perineural invasion (PNI) for locally advanced gastric cancer (LAGC).This work prospectively included 196 surgically resected LAGC patients (139 males, 57 females, 59.55 ± 11.97 years) undergoing triple enhanced spectral CT scans. Patients were labeled as perineural invasion (PNI) positive and negative according to pathologic reports, then further split into primary (n = 130) and validation cohort (n = 66). We extracted clinicopathological information, follow-up data, iodine concentration (IC), and normalized IC values against to aorta (nICs) at arterial/venous/delayed phases (AP/VP/DP). Clinicopathological features and IC values between PNI positive and negative groups were compared. Multivariable logistic regression was performed to screen independent risk factors of PNI. Then, a nomogram was established, and its capability was determined by ROC curves. Its clinical use was evaluated by decision curve analysis. The correlations of PNI and the nomogram with patients' survival were explored by log-rank survival analysis.Borrmann classification, tumor thickness, and nICDP were independent predictors of PNI and used to build the nomogram. The nomogram yielded higher AUCs of 0.853 (0.744-0.928) and 0.782 (0.701-0.850) in primary and validation cohorts than any other parameters (p < 0.05). Both PNI and the nomogram were related to post-surgical treatment planning. Only PNI was associated with disease-free survival in the primary cohort (p < 0.05).This work prospectively established a spectral CT-based nomogram, which can effectively predict PNI preoperatively and potentially guide post-surgical treatment strategy in LAGC.• The present prospective study established a spectral CT-based nomogram for preoperative prediction of perineural invasion in LAGC. • The proposed nomogram, including morphological features and the quantitative iodine concentration values from spectral CT, had the potential to predict PNI for LAGC before surgery, along with guide post-surgical treatment planning. • Normalized iodine concentration at the delayed phase was the most valuable quantitative parameter, suggesting the importance of delayed enhancement in gastric CT.© 2023. The Author(s), under exclusive licence to European Society of Radiology.