Division of Oncology, Department of Medicine, University of Washington, Seattle Cancer Care Alliance, Seattle, WA.
Department of Urology, University of Washington, Seattle, WA.
Clin Genitourin Cancer. 2021 Apr;19(2):144-154. doi: 10.1016/j.clgc.2020.10.002. Epub 2020 Oct 14.
Micropapillary urothelial carcinoma (MPC) is a rare urothelial carcinoma variant with conflicting data guiding clinical practice. In this study, we explored oncologic outcomes in relation to neoadjuvant chemotherapy (NAC) in a retrospective cohort of patients with MPC, alongside data from Surveillance, Epidemiology, and End Results (SEER)-Medicare.
We retrospectively identified patients with MPC or conventional urothelial carcinoma (CUC) without any variant histology undergoing radical cystectomy (RC) in our institution (2003-2018). SEER-Medicare was also queried to identify patients diagnosed with MPC (2004-2015). Clinicopathologic data and treatment modalities were extracted. Overall survival (OS) was estimated with the Kaplan-Meier method. Mann-Whitney-Wilcoxon and chi-square tests were used for comparative analysis and Cox regression for identifying clinical covariates associated with OS.
Our institutional database yielded 46 patients with MPC and 457 with CUC. In SEER-Medicare, 183 patients with MPC were identified, and 63 (34%) underwent RC. In the institutional cohort, patients with MPC had significantly higher incidence of cN+ (17% vs. 8%), pN+ stage (30% vs. 17%), carcinoma-in-situ (43% vs. 25%), and lymphovascular invasion (30% vs. 16%) at RC versus those with CUC (all P < .05). Pathologic complete response (ypT0N0) to NAC was 33% for MPC and 35% for CUC (P = .899). Median OS was lower for institutional MPC versus CUC in univariate analysis (43.6 vs. 105.3 months, P = .006); however, MPC was not independently associated with OS in the multivariate model. Median OS was 25 months in the SEER MPC cohort for patients undergoing RC, while NAC was not associated with improved OS in that group.
Pathologic response to NAC was not significantly different between MPC and CUC, while MPC histology was not an independent predictor of OS. Further studies are needed to better understand biological mechanisms behind its aggressive features as well as the role of NAC in this histology variant.
微乳头尿路上皮癌（MPC）是一种罕见的尿路上皮癌变异型，其临床实践指导数据存在冲突。在这项研究中，我们通过回顾性队列研究，探讨了接受新辅助化疗（NAC）的 MPC 患者的肿瘤学结果，并结合监测、流行病学和最终结果（SEER）-医疗保险的数据。
我们回顾性地确定了在我们机构接受根治性膀胱切除术（RC）的 MPC 或无任何变异组织学的常规尿路上皮癌（CUC）患者（2003-2018 年）。还通过 SEER-医疗保险查询了 2004-2015 年诊断为 MPC 的患者。提取临床病理数据和治疗方式。使用 Kaplan-Meier 法估计总生存期（OS）。使用 Mann-Whitney-Wilcoxon 和卡方检验进行比较分析，使用 Cox 回归分析与 OS 相关的临床协变量。
我们的机构数据库中共有 46 例 MPC 患者和 457 例 CUC 患者。在 SEER-医疗保险中，确定了 183 例 MPC 患者，其中 63 例（34%）接受了 RC。在机构队列中，与 CUC 患者相比，MPC 患者在 RC 时的 cN+（17%对 8%）、pN+期（30%对 17%）、原位癌（43%对 25%）和血管淋巴管侵犯（30%对 16%）发生率显著更高（均 P<.05）。MPC 对 NAC 的病理完全缓解（ypT0N0）率为 33%，CUC 为 35%（P=.899）。单因素分析中，机构 MPC 与 CUC 的中位 OS 较低（43.6 对 105.3 个月，P=.006）；然而，多因素模型中 MPC 与 OS 无关。SEER MPC 队列中接受 RC 的患者的中位 OS 为 25 个月，而 NAC 并未改善该组的 OS。
MPC 和 CUC 之间对 NAC 的病理反应无显著差异，而 MPC 组织学不是 OS 的独立预测因子。需要进一步的研究来更好地了解其侵袭性特征背后的生物学机制，以及 NAC 在这种组织学变异中的作用。
