cT1期肾癌术后升期为pT3a期风险因素的列线图预测模型

Risk nomogram model for predicting the postoperative upgrade to pT3a of cT1 renal cancer

目的评估cT1期肾癌术后升期为pT3a期的风险因素,建立术后升期的列线图预测模型,以提高预测肾癌局部进展的能力。方法回顾性分析2010年1月至2016年12月天津医科大学第二医院手术治疗的1376例cT1期(直径≤7cm)肾肿瘤患者的临床资料。男979例,女397例;年龄(57.65±10.92)岁;体质指数(25.47±3.27)kg/m2;肿瘤长径(4.02±1.52)cm;左侧肿瘤711例,右侧肿瘤665例;363例有临床症状,567例有吸烟史,732例有慢性疾病史。CT检查示289例有肿瘤坏死,636例有肿瘤外凸,822例肿瘤轮廓不规则,738例有肾窦压迫。396例行肾部分切除术,980例行根治性肾切除术。单因素分析采用Mann-WhitneyU检验和χ^2检验,多因素分析采用logistic回归分析术后升期的预测因子,R软件进行列线图预测模型的构建,C-index评价模型区分度,校准曲线法评价模型的一致性。结果1376例术后病理诊断为肾透明细胞癌1195例,乳头状细胞癌48例,嫌色细胞癌57例,其他类型76例。1376例cT1期肾肿瘤患者中75例术后升期为pT3a期,占5.5%。单因素分析结果显示,升期至pT3a期的患者较未升期至pT3a期的患者年龄大[(63.08±10.17)岁与(57.34±10.88)岁]、肿瘤长径大[(5.24±1.35)cm与(3.95±1.51)cm],有临床症状的比例高[46.7%(35/75)与25.2%(328/1301)],CT检查提示肿瘤坏死[40.0%(30/75)与19.9%(259/1301)]、肿瘤轮廓不规则[73.3%(55/75)与59.0%(767/1301)]及行根治性肾切除术[(92.1%(70/75)与70%(910/1301)]的比例高,差异均有统计学意义(P<0.01)。多因素分析结果示升期的独立预测因素是年龄较大(OR=1.046,P<0.001)、肿瘤较大(OR=1.504,P<0.001)、有临床症状(OR=2.153,P=0.004)、肿瘤轮廓不规则(OR=2.466,P=0.002)、CT检查提示肿瘤坏死(OR=2.588,P<0.001)。C-index为0.808,校准曲线与理想曲线贴合良好,说明模型在预测肾癌升期风险上与实际升期风险有较好的一致性。结论本研究基于5个术前预测因素即年龄、肿瘤大小、有无临床症状、肿瘤轮廓是否规则、CT检查肿瘤有无坏死,开发了预测cT1期肾癌升期为pT3a期风险的列线图。该列线图具有较好的预测效力,在肾癌手术治疗前可为医生制订治疗决策提供参考。

Objective To evaluate the risk factors of postoperative upgrade to pT3a of cT1 renal cell carcinoma, and to establish a nomogram prediction model to improve the ability of predicting locally advanced renal cell carcinoma and provide a reference for clinical surgical decision-making. Methods Clinical data of 1 376 patients with cT1 (diameter ≤ 7 cm) renal tumor hospitalized for surgery from January 2010 to December 2016 were retrospectively analyzed. There were 979 males and 397 females, with the mean age of (57.65±10.92) years. The mean body mass index (BMI) was (25.47±3.27) kg/m2 and the average tumor size was (4.02±1.52) cm. There were 711 tumors on the left and 665 on the right. There were 363 cases with clinical symptoms, 567 patients with smoking history , 732 cases with history of chronic disease. There were 289 cases with tumor necrosis, 636 cases with tumor protrusion, 822 cases with irregular tumor , and 738 cases with renal sinus compression. Partial nephrectomy and radical nephrectomy were performed in 396 cases and 980 cases respectively. Mann-whitney U test and chi-square test were used for univariate analysis, logistic regression analysis was used for multivariate analysis to analyze the predictors of upgrading, R software was used to construct the nomogram predictive model, C-index was used to evaluate the model discrimination, and calibration curve method was used to evaluate the consistency of the model. Results Postoperative pathology of total 1 376 cases showed that there were 1 195 cases of clear cell carcinoma of kidney, 48 cases of papillary cell carcinoma, 57 cases of chromophobe cell carcinoma, and 76 cases of other types. Among the 1 376 patients with cT1 renal tumor, 75 patients were upgraded to pT3a, accounting for 5.5% of all patients. Univariate analysis showed that the patients who upgraded to pT3a were older [(63.08±10.17) years old and (57.34±10.88) years old], and the tumor length and diameter were larger [(5.24±1.35) cm and (3.95±1.51) cm]. Patients with clinical symptoms [46.7%(35/75) vs. 25.2%(328/1 301)], patients with CT indication of tumor necrosis [40.0%(30/25 975) vs. 19.9%(259/1 301)], patients with irregular tumor contour [73.3%(55/76 775) vs. 59.0%(767/1 301)], and patients with radical nephrectomy were higher [(92.1%(70/91 075) vs. 70%(910/1 301)]. All the differences were statistically significant (P<0.01). Multivariate analysis showed that the independent predictors of upgrading were age (OR=1.046, P<0.001), larger tumor (OR=1.504, P<0.001), clinically symptom (OR=2.153, P=0.004), irregular tumor profile (OR=2.466, P=0.002), and tumor necrosis on CT (OR=2.588, P<0.001). The C-index was 0.808, the calibration curve of forecasting curve with the standard curve fit was good, and the prediction of renal cancer are better in predict consistency. Conclusions Based on the five preoperative predictors, including age, tumor size, clinical presence or absence of symptoms, tumor profile, and whether or not the tumor necrosis indicated by CT, this study developed a nomogram of cT1 renal cancer upgrade to pT3a. This nomogram has a good statistical significance, and this model can provide prognosis consultation for patients and provide reference for doctors to make decisions before treatment.