Department of Radiation Oncology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Rui Jin Er Road, Shanghai, 200025, China.
Department of Radiation Oncology, Institute Curie, Paris, France.
Radiat Oncol. 2019 Jul 17;14(1):128. doi: 10.1186/s13014-019-1332-y.
Lacking quantitative evaluations of clinicopathological features and the risk factors for loco-regional recurrence (LRR) in gastric cancer after D2 gastrectomy, we aimed to develop a competing risk nomogram to identify the risk predictors for initial LRR.
We retrospectively analysed 1105 patients who underwent radical gastrectomy with D2 resection for stage I-III gastric cancer. A nomogram predicting initial LRR of gastric cancer was conducted based on Fine and Grey's competing risk analysis. The predictive accuracy and discriminative ability of the model were determined using the concordance index (C-index) and calibration curve. Decision tree analysis was performed for patient grouping.
At a median follow-up of 28.4 months, 274 patients developed 373 first recurrence events (local, regional, and distant disease). The median recurrence-free survival (RFS) was 16.7 months. Multivariate competing risk analysis showed that age (SHR, 1.72; 95% CI, 1.10-2.83, p = 0.031), CEA (SHR, 1.94; 95% CI, 1.09-3.46, p = 0.024), pT4 (SHR, 2.77; 95% CI, 1.01-7.57, p = 0.047), lymph node metastasis (SHR 1.92, 95% CI: 1.09-3.38, p = 0.024) and LVI (SHR, 1.84; 95% CI, 1.06-3.20, p = 0.028) were independent risk factors for LRR (all p < 0.05). The nomogram incorporating these factors achieved good agreement between prediction and actual observation with a concordance index of 0.738 (95% CI, 0.767 to 0.709). In a subgroup analysis of node-positive patients, pN3b was associated with increased peritoneal and distant metastasis (p = 0.048). The para-aortic lymph nodes were the most frequent sites (n = 71) of LRR, and among them, the 16a2 and 16b1 nodes exhibited even more prevalence (90.1 and 81.7%).
Adjuvant radiotherapy might be recommended in gastric cancer patients ≥65 years old or those with pN+, pT4, LVI, or increased CEA levels, particularly in high-risk or pN1-3a patients. The competing risk nomograms may be considered as convenient and individualized predictive tools for LRR in gastric cancer after D2 gastrectomy. It is also recommended that the clinical target volume (CTV) include 16a2 and 16b1 regions of para-aortic lymph nodes.
由于缺乏对胃癌 D2 胃切除术后局部区域复发（LRR）的临床病理特征和危险因素的定量评估，我们旨在建立一个竞争风险列线图，以确定初始 LRR 的风险预测因素。
我们回顾性分析了 1105 例接受根治性 D2 胃切除术治疗 I-III 期胃癌的患者。基于 Fine 和 Grey 的竞争风险分析，建立了预测胃癌初始 LRR 的列线图。通过一致性指数（C 指数）和校准曲线来确定模型的预测准确性和判别能力。对患者进行分组进行决策树分析。
中位随访 28.4 个月时，274 例患者发生了 373 例首次复发事件（局部、区域和远处疾病）。中位无复发生存期（RFS）为 16.7 个月。多变量竞争风险分析显示，年龄（SHR，1.72；95%CI，1.10-2.83，p=0.031）、CEA（SHR，1.94；95%CI，1.09-3.46，p=0.024）、pT4（SHR，2.77；95%CI，1.01-7.57，p=0.047）、淋巴结转移（SHR 1.92，95%CI：1.09-3.38，p=0.024）和 LVI（SHR，1.84；95%CI，1.06-3.20，p=0.028）是 LRR 的独立危险因素（均 p<0.05）。纳入这些因素的列线图在预测与实际观察之间具有良好的一致性，一致性指数为 0.738（95%CI，0.767 至 0.709）。在淋巴结阳性患者的亚组分析中，pN3b 与腹膜和远处转移增加相关（p=0.048）。主动脉旁淋巴结是 LRR 最常见的部位（n=71），其中 16a2 和 16b1 淋巴结更为常见（90.1%和 81.7%）。
对于年龄≥65 岁或伴有 pN+、pT4、LVI 或 CEA 水平升高的胃癌患者，建议辅助放疗，尤其是在高危或 pN1-3a 患者中。竞争风险列线图可作为 D2 胃切除术后胃癌 LRR 的方便、个体化预测工具。还建议临床靶区（CTV）包括主动脉旁淋巴结的 16a2 和 16b1 区域。
