Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou; Guangdong Provincial Key Laboratory on Precision and Minimally Invasive Medicine for Gastrointestinal Cancers, Guangzhou, China; Department of Radiation Oncology, Stanford University School of Medicine, Stanford, USA.
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, USA.
Ann Oncol. 2020 Jun;31(6):760-768. doi: 10.1016/j.annonc.2020.03.295. Epub 2020 Mar 30.
The tumor immune microenvironment can provide prognostic and predictive information. A previously validated ImmunoScore of Gastric Cancer (IS) evaluates both lymphoid and myeloid cells in the tumor core and invasive margin with immunohistochemical staining of surgical specimens. We aimed to develop a noninvasive radiomics-based predictor of IS.
In this retrospective study including four independent cohorts of 1778 patients, we extracted 584 quantitative features from the intratumoral and peritumoral regions on contrast-enhanced computed tomography images. A radiomic signature [radiomics ImmunoScore (RIS)] was constructed to predict IS using regularized logistic regression. We further evaluated its association with prognosis and chemotherapy response.
A 13-feature radiomic signature for IS was developed and validated in three independent cohorts (area under the curve = 0.786, 0.745, and 0.766). The RIS signature was significantly associated with both disease-free and overall survival in the training and all validation cohorts [hazard ratio (HR) range: 0.296-0.487, all P < 0.001]. In multivariable analysis, the RIS remained an independent prognostic factor adjusting for clinicopathologic variables (adjusted HR range: 0.339-0.605, all P < 0.003). For stage II and stage III disease, patients with a high RIS derived survival benefit from adjuvant chemotherapy {HR = 0.436 [95% confidence interval (CI) 0.253-0.753], P = 0.002; HR = 0.591 (95% CI 0.428-0.818), P < 0.001, respectively}, whereas those with a low RIS did not.
The RIS is a reliable tool for evaluation of immunoscore and retains the prognostic significance in gastric cancer. Future prospective studies are required to confirm its potential to predict treatment response and select patients who will benefit from chemotherapy.
肿瘤免疫微环境可以提供预后和预测信息。之前经过验证的胃癌免疫评分（IS）通过对手术标本的免疫组织化学染色评估肿瘤核心和浸润边缘的淋巴和髓样细胞。我们旨在开发一种基于非侵入性放射组学的 IS 预测因子。
在这项包括四个独立队列的 1778 例患者的回顾性研究中，我们从增强 CT 图像的肿瘤内和肿瘤周围区域提取了 584 个定量特征。使用正则化逻辑回归构建放射组学特征（RIS）来预测 IS。我们进一步评估了它与预后和化疗反应的关系。
建立并验证了一个由 13 个特征组成的 IS 放射组学签名，在三个独立队列中（曲线下面积：0.786、0.745 和 0.766）。RIS 签名与训练队列和所有验证队列的无病生存率和总生存率显著相关[风险比（HR）范围：0.296-0.487，所有 P < 0.001]。多变量分析中，RIS 仍然是一个独立的预后因素，可调整临床病理变量（调整后的 HR 范围：0.339-0.605，所有 P < 0.003）。对于 II 期和 III 期疾病，高 RIS 的患者从辅助化疗中获益[HR=0.436（95%CI 0.253-0.753），P=0.002；HR=0.591（95%CI 0.428-0.818），P<0.001]，而低 RIS 的患者则没有。
RIS 是评估免疫评分的可靠工具，在胃癌中保留了预后意义。需要进一步的前瞻性研究来证实其预测治疗反应和选择受益于化疗的患者的潜力。
