Department of Radiological, Oncological and Pathological Sciences, Policlinico Umberto I, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
Department of Radiotherapy, Policlinico Umberto I, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
Eur Radiol. 2023 Feb;33(2):854-862. doi: 10.1007/s00330-022-09086-7. Epub 2022 Aug 18.
To investigate the predictive role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the assessment of response to total neoadjuvant therapy (TNT) in patients with locally advanced rectal cancer (LARC).
In this single-center retrospective study, patients with LARC who underwent staging MRI and TNT were enrolled. MRI-based staging, tumor volume, and DWI-ADC values were analyzed. Patients were classified as complete responders (pCR) and non-complete responders (non-pCR), according to post-surgical outcome. Pre-treatment ADC values were compared to pathological outcome, post-treatment downstaging, and reduction of tumor volume. The diagnostic accuracy of DWI-ADC in differentiating between pCR and non-pCR groups was calculated with receiver operating characteristic (ROC) analysis.
A total of 36 patients were evaluated (pCR, n = 20; non-pCR, n = 16). Pre-treatment ADC values were significantly different between the two groups (p = 0.034), while no association was found between pre-TNT tumor volume and pathological response. ADC values showed significant correlations with loco-regional downstaging after therapy (r = -0.537, p = 0.022), and with the reduction of tumor volume (r = -0.480, p = 0.044). ADC values were able to differentiate pCR from non-pCR patients with a sensitivity of 75% and specificity of 70%.
ADC values on pre-treatment MRI were strongly associated with the outcome in patients with LARC, both in terms of pathological response and in loco-regional downstaging after TNT, suggesting the use of DW-MRI as a potential predictive tool of response to therapy.
• ADC values of pre-TNT MRI examinations of patients with LARC were significantly associated with a pathological complete response (pCR) and with post-treatment regression of TNM staging. • An ADC value of 1.042 ×10 mm/s was found to be the optimal cutoff value for discriminating between pCR and non-pCR patients, with a sensitivity of 75% and specificity of 70%. • DW-MRI proved to have a potential predictive role in the assessment of response to therapy in patients with LARC, throughout the analysis of ADC map values.
探讨弥散加权磁共振成像（DW-MRI）在评估局部进展期直肠癌（LARC）患者全新辅助治疗（TNT）反应中的预测作用。
本单中心回顾性研究纳入了接受分期 MRI 和 TNT 的局部进展期直肠癌患者。分析了 MRI 分期、肿瘤体积和 DWI-ADC 值。根据术后结果将患者分为完全缓解者（pCR）和非完全缓解者（非-pCR）。比较治疗前 ADC 值与病理结果、治疗后降期和肿瘤体积缩小的关系。采用受试者工作特征（ROC）曲线分析 DWI-ADC 鉴别 pCR 组和非-pCR 组的诊断准确性。
共评估了 36 例患者（pCR 组，n=20；非-pCR 组，n=16）。两组间治疗前 ADC 值差异有统计学意义（p=0.034），而治疗前肿瘤体积与病理反应之间无相关性。ADC 值与治疗后局部降期（r=-0.537，p=0.022）和肿瘤体积缩小（r=-0.480，p=0.044）显著相关。ADC 值能够以 75%的敏感性和 70%的特异性区分 pCR 与非-pCR 患者。
LARC 患者治疗前 MRI 的 ADC 值与病理反应以及 TNT 后局部降期密切相关，提示 DW-MRI 可作为治疗反应的潜在预测工具。
LARC 患者 TNT 前 MRI 检查的 ADC 值与病理完全缓解（pCR）和治疗后 TNM 分期消退显著相关。
1.042×10 mm/s 的 ADC 值被发现是区分 pCR 与非-pCR 患者的最佳截断值，其敏感性为 75%，特异性为 70%。
通过 ADC 图值分析，DW-MRI 证明在评估 LARC 患者对治疗的反应方面具有潜在的预测作用。
