Introduction: Upper tract urothelial carcinoma (UTUC) is a rare genitourinary malignancy that represents only 5-10% of all urothelial carcinoma (UC). While the majority of these cancers will be derived from urothelium, variant histology (VH) is reported in < 5% of these cases. We sought to identify prognostic and treatment factors for variant histology of UTUC using a nationwide database.
Methods: The National Cancer Database (NCDB) was queried for all cases of UTUC from 2004-2016. Patients with other cancer diagnoses, metastasis, and/or diagnosis on autopsy were excluded. Kaplan-Meier and Cox proportional hazards regression were used to identify independent predictors of overall survival.
Results: We identified 27,737 patients with UC versus 1,093 with VH, respectively. VH presented at both higher T and N stage versus UC and was more commonly metastatic. Not only was overall median survival significantly worse for VH (30 months, 95% CI 22.3 – 37.8 versus 67.5 months, 95% CI 63.3 – 73.0) but also inferior when stratified by stage. On multivariable cox proportional hazards analysis, VH was associated with worse hazards of survival versus UC (HR 1.341, 95% CI 1.196 – 1.504). On sub-analysis, patients who were =pT2N0/XM0/X or pN+M0/X after radical nephroureterectomy appeared to benefit from adjuvant chemotherapy across both UC and VH with improved hazards of survival.
Conclusions: Variant histology of the upper urinary tract is associated with later stage at presentation and worse survival when compared to UC, even when adjusted for stage. Adjuvant chemotherapy may improve survival in this cohort. Source of