三种淋巴结指标对阴茎鳞状细胞癌预后的预测价值比较

Comparison of three lymph node indicators in predicting prognosis of squamous cell carcinoma of the penis

目的探讨阳性淋巴结数量(NMLN)、阳性淋巴结比率(LNR)和阳性淋巴结对数比(LODDS)对阴茎鳞状细胞癌(SCCP)患者预后的预测价值。方法选取2004年—2019年SEER数据库中诊断为SCCP且进行淋巴结清扫的患者作为研究对象,剔除缺失值,最终纳入781例,平均年龄(61.46±12.73)岁。参考2017年AJCC阴茎癌TNM分期系统,将研究对象分为NMLNⅠ期、NMLNⅡ期、NMLNⅢ期;使用X-tile软件确定LNR和LODDS的截断值,将研究对象分为LNRⅠ期、LNRⅡ期、LNRⅢ期和LODDSⅠ期、LODDSⅡ期、LODDSⅢ期。使用Kaplan-Meier法绘制生存曲线并使用Log-rank检验比较组间差异。将单因素分析结果中差异具有统计学意义的变量作为协变量,分别与NMLN分期、LNR分期、LODDS分期纳入Cox比例风险模型并进行模型评价。根据是否有淋巴结包膜外侵犯(ENE)或盆腔淋巴结转移进行亚组分析。结果Log-rank检验显示,在NMLN分期(χ^(2)=97.964,P<0.001)、LNR分期(χ^(2)=187.786,P<0.001)和LODDS分期(χ^(2)=183.486,P<0.001)中,各期患者肿瘤特异性生存期(CSS)比较差异具有统计学意义。单因素分析结果显示,年龄、分化程度、T分期、M分期、NMLN分期、LNR分期和LODDS分期为SCCP患者CSS的影响因素(P<0.05)。多因素分析结果显示,NMLN分期、LNR分期和LODDS分期均为SCCP患者CSS的独立影响因素(P<0.05)。模型评价结果显示,纳入LNR分期、LODDS分期的Cox回归模型,在模型准确性和拟合度上无显著差异,且均优于纳入NMLN分期的模型。亚组分析结果显示,有ENE或盆腔淋巴结转移的亚组中,LNR分期和LODDS分期为SCCP患者CSS的独立影响因素(P<0.05),NMLN不是影响因素(P>0.05),纳入NMLN分期的Cox回归模型C指数小于0.7,准确性较差,在模型准确性和拟合度上均比纳入LNR分期和LODDS分期的模型差。结论LNR和LODDS能够更好地预测SCCP患者的预后,在ENE或盆腔淋巴结转移的SCCP患者中,同样具有一定的预测能力。

Objective To investigate the predictive value of number of metastatic lymph nodes(NMLN),lymph node ratio(LNR),and log odds of positive lymph nodes(LODDS)on the prognosis of patients with squamous cell carcinoma of the penis(SCCP).Methods The data from patients diagnosed with SCCP and who underwent lymph node dissection between 2004 and 2019 from the SEER database were selected as study objects.After excluding cases with missing values,a total of 781 patients with a mean age of 61.46±12.73 years were finally included in the study.According to the 2017 AJCC penile cancer tumor node metastasis(TNM)staging system,study objects were classified into NMLN stageⅠ,Ⅱ,andⅢ;the cut-off values for LNR and LODDS were determined using X-tile software,and patients were classified into LNR stageⅠ,Ⅱ,andⅢand LODDS stageⅠ,Ⅱ,andⅢ.Kaplan-Meier curves were plotted and Log-rank tests were used to compare differences between groups.Variables with statistically significant differences identified from univariate analysis were included as covariates and separately incorporated into Cox proportional hazards models for NMLN staging,LNR staging,and LODDS staging,followed by model evaluation.Subgroup analyses were conducted according to the presence or absence of extranodal extension(ENE)or pelvic lymph node metastasis.Results Log-rank tests revealed statistically significant differences in cancer-specific survival(CSS)among patients in NMLN staging(χ^(2)=97.964,P<0.001),LNR staging(χ^(2)=187.786,P<0.001),and LODDS staging(χ^(2)=183.486,P<0.001).Univariate analysis showed that age,differentiation degree,T stage,M stage,NMLN stage,LNR stage,and LODDS stage were factors affecting CSS in SCCP patients(P<0.05).Multivariate analysis indicated that NMLN staging,LNR staging,and LODDS staging were independent prognostic factors for CSS in SCCP patients(P<0.05).The model evaluation shows no significant difference in accuracy and goodness of fit between Cox regression models using LNR staging and LODDS staging.Additionally,both models perform better than the model using NMLN staging.Subgroup analysis revealed that in the subgroup with ENE or pelvic lymph node metastasis,LNR staging and LODDS staging were independent prognostic factors for CSS in SCCP patients(P<0.05),while NMLN staging was not(P>0.05);the C-index of the Cox regression model incorporating NMLN staging was less than 0.7,indicating poor accuracy,and the model′s accuracy and goodness-of-fit were inferior to those incorporating LNR staging and LODDS staging.Conclusions LNR and LODDS show superior predictive ability for the prognosis of patients with SCCP.They also demonstrate predictive capacity in SCCP patients with ENE or pelvic lymph node metastasis.