光子计数CT在胃肠道恶性肿瘤中的应用：范围综述
最一致的发现是低keV虚拟单能成像改善胰腺癌病灶对比噪声比、提高可切除性评估的读者间一致性，并降低腹部辐射剂量；肝细胞癌、肝转移、直肠癌和食管癌证据仍属初步。
要点
- 低keV虚拟单能成像可改善胰腺癌病灶对比噪声比和可切除性评估的读者间一致性。
- 光子计数CT较能量积分探测器CT可降低腹部辐射剂量。
- 直肠癌T分期准确性与MRI相当，并可提取碘基定量生物标志物。
核心结论
- 光子计数CT是胃肠道肿瘤成像的重要技术进展，早期临床前景良好。
- 最一致且可重复的发现集中于胰腺腺癌低keV虚拟单能成像的肿瘤显影改善和血管受累读者间一致性提高，以及腹部辐射剂量降低。
- 肝细胞癌、肝转移、直肠癌和食管癌的证据仅为初步，来自每类肿瘤仅一至两项研究，应视为探索性和假设生成性。
研究设计与样本
- 质量评估采用纽卡斯尔-渥太华量表，证据等级依据牛津循证医学中心标准分级。
- 未进行荟萃分析，文中报告的各研究数值范围为异质性个体研究的分布，不构成汇总的荟萃分析估计。
关键影像表现/征象
- 在胰腺和肝脏恶性肿瘤中，个体研究报告低keV虚拟单能成像下病灶对比噪声比改善，各研究范围为45%至65%。
- 与能量积分探测器CT相比，腹部辐射剂量降低的各研究范围为25%至40%。
- 胰腺癌可切除性评估的读者间一致性，光子计数CT的κ值为0.61至0.69，能量积分探测器CT为0.56至0.59。
- 光子计数CT对直肠癌T分期的准确性与MRI相当（70% vs 73.3%）。
- 光子计数CT可提取与直肠癌和食管癌治疗反应相关的定量碘基生物标志物。
诊断标准与关键数值
- 直肠癌T分期准确性：光子计数CT为70%，MRI为73.3%。
- 胰腺癌可切除性评估读者间一致性：光子计数CT的κ=0.61-0.69，能量积分探测器CT的κ=0.56-0.59。
- 低keV虚拟单能成像下胰腺和肝脏恶性肿瘤病灶对比噪声比改善的各研究范围为45%-65%。
- 腹部辐射剂量较能量积分探测器CT降低的各研究范围为25%-40%。
临床应用与阅片要点
- 日常阅片可关注低keV虚拟单能图像在胰腺癌病灶显示和血管受累评估中的辅助价值。
- 报告胰腺癌可切除性时，可参考光子计数CT提高读者间一致性的证据，但需注意证据来自回顾性单中心研究。
- 利用光子计数CT的辐射剂量优势时，应结合具体扫描方案个体化调整。
- 直肠癌T分期仍以MRI为参考，光子计数CT可作为补充或替代选择之一，但证据尚不充分。
- 对肝细胞癌、肝转移和食管癌的光子计数CT应用应保持审慎，避免过度解读初步证据。
局限性
- 总体证据基础以2b-3级为主，基于回顾性单中心队列和替代诊断终点。
- 未进行荟萃分析，各研究间异质性大，报告的范围不代表汇总估计。
- 肝细胞癌、肝转移、直肠癌和食管癌的证据仅来自每类肿瘤一至两项研究，研究问题异质，属探索性。
- 需要前瞻性多中心试验进一步验证。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
BACKGROUND: Photon-Counting computed tomography(PCCT) offers superior spatial resolution, improved contrast-to-noise ratio and reduced radiation dose compared with conventional CT. This scoping review maps and synthesizes clinical evidence on PCCT applications in gastrointestinal (GI) oncology following the PRISMA Extension for Scoping Reviews (PRISMA-ScR) guidelines METHODS: A systematic search of PubMed, Embase, Web of Science and Cochrane Library (January 2017-December 2025) identified studies evaluating PCCT in adult patients with confirmed GI malignancies. Quality was assessed using the Newcastle-Ottawa Scale and levels of evidence were graded according to the Oxford Centre for Evidence-Based Medicine.
RESULTS: Thirteen studies (761 patients) met inclusion criteria. Across pancreatic and hepatic malignancies, individual studies reported improvements in lesion contrast-to-noise ratio at low-keV virtual monoenergetic imaging (range across studies, 45-65%), abdominal radiation dose reductions compared with energy-integrating detector CT (range, 25-40%), and improved inter-reader agreement for pancreatic cancer resectability (κ = 0.61-0.69 with PCCT vs 0.56-0.59 with EID-CT). These ranges represent the spread across heterogeneous individual studies and do not constitute pooled meta-analytic estimates, as no meta-analysis was performed (see Section 2.8). PCCT showed comparable accuracy to MRI for rectal cancer T-staging (70% vs 73.3%) and enabled quantitative iodine-based biomarkers associated with treatment response in rectal and esophageal cancer.
CONCLUSIONS: PCCT represents a substantial technical advance with early clinical promise in GI oncologic imaging. The most consistent and reproducible findings concern pancreatic adenocarcinoma (improved tumor conspicuity at low-keV VMI and improved inter-reader agreement for vascular involvement) and abdominal radiation dose reduction. Evidence for hepatocellular carcinoma, liver metastases, rectal cancer, and esophageal cancer is preliminary, derived from only one or two studies per tumor type that address heterogeneous research questions, and should therefore be regarded as exploratory and hypothesis-generating. The overall evidence base is predominantly Level 2b-3 and based on retrospective single-centre cohorts and surrogate diagnostic endpoints, underscoring the need for prospective multicentre trials.
引用
- Spoto F, Robertis R, Monterubbiano L, et al. Photon-counting CT in gastrointestinal malignancies: a scoping review. Eur J Radiol. 2026. PMID: 42102569. doi:10.1016/j.ejrad.2026.112905
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。