Background: The importance of lymph node dissection (LND) at the time of radical cystectomy for urothelial carcinoma (UC) is widely accepted despite known risks. The therapeutic benefits of LND for variant subtype bladder cancer (VBC), a heterogenous and distinct set of diseases, are not well established. We aim to characterize the impact of LND on overall survival across VBC subtypes. Methods: The National Cancer Database was queried for all cases of variant subtype bladder cancer managed with radical cystectomy between 2004 and 2020, using the International Classification of Disease-O-3 morphological codes. The cases were stratified by receipt of individual variant subtypes. The primary outcome was overall survival associated with pathologic nodal status and receipt of nodal dissection. A Kaplan–Meier analysis and Cox proportional hazards analysis were used for survival analyses. Results: A total of 30,911 patients with VBC that were managed with radical cystectomy were included in our analysis. The pNx rates ranged from 33.1% in the micropapillary subtype, 42.2% in the sarcomatoid subtype, 68.4% in the squamous subtype, 48.9% in the adenocarcinoma subtype, and 56.2% in the neuroendocrine subtype. The median OS was higher in those that received a nodal dissection across subtypes but was statistically significant only for the squamous (71.0 [68.0 vs. 74.0] vs. 37.2 [33.6 vs. 40.9] monthsp< 0.001) and adenocarcinoma (45.9 [32.9 vs. 59.0] vs. 37.9 [28.6 vs. 47.1] monthsp= 0.037) subtypes. Using Cox proportional hazards regression, LN dissection was associated with improved OS for the squamous (0.50 (0.44–0.58)p< 0.001) and adenocarcinoma (0.65 [0.45–0.93)p= 0.030) subtypes. Conclusions: The role of LND across VBC subtypes is not clearly defined and warrants further investigation to develop a more risk-adaptive approach. We demonstrate heterogeneity with respect to the OS benefit associated with LND at the time of surgery. Among certain VBC subtypes, LND may not offer a significant therapeutic benefit, while LND in squamous and adenocarcinoma VBCs is correlated with improved survival.
背景：尽管存在已知风险，根治性膀胱切除术中淋巴结清扫（LND）对于尿路上皮癌（UC）的重要性已被广泛认可。然而，对于变异亚型膀胱癌（VBC）这一组异质性且独特的疾病，LND的治疗获益尚未明确。本研究旨在评估LND对不同VBC亚型患者总生存期的影响。 方法：通过查询美国国家癌症数据库，使用国际疾病分类-O-3形态学编码，筛选出2004年至2020年间接受根治性膀胱切除术的所有VBC病例。病例按具体变异亚型进行分层。主要研究终点是与病理淋巴结状态及是否接受淋巴结清扫相关的总生存期。采用Kaplan-Meier分析和Cox比例风险模型进行生存分析。 结果：本研究共纳入30,911例接受根治性膀胱切除术的VBC患者。各亚型pNx（未评估淋巴结）率分别为：微乳头亚型33.1%、肉瘤样亚型42.2%、鳞状亚型68.4%、腺癌亚型48.9%、神经内分泌亚型56.2%。接受淋巴结清扫的患者在各亚型中的中位总生存期均较高，但仅在鳞状亚型（71.0 [68.0-74.0] 月 vs. 37.2 [33.6-40.9] 月，p<0.001）和腺癌亚型（45.9 [32.9-59.0] 月 vs. 37.9 [28.6-47.1] 月，p=0.037）中差异具有统计学意义。Cox比例风险回归分析显示，淋巴结清扫与鳞状亚型（HR=0.50，95%CI 0.44-0.58，p<0.001）和腺癌亚型（HR=0.65，95%CI 0.45-0.93，p=0.030）的总生存期改善相关。 结论：LND在不同VBC亚型中的作用尚未明确界定，需要进一步研究以制定更具风险适应性的治疗策略。本研究表明，手术时进行LND带来的总生存获益存在异质性。在某些VBC亚型中，LND可能无法提供显著的治疗获益，而在鳞状细胞癌和腺癌亚型中，LND与生存改善相关。
Evaluating the Therapeutic Role of Lymph Node Dissection in Variant Subtype Bladder Cancer
肿瘤(癌症)患者之家