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Updated: Aug 5, 2026
Retzius-Sparing Robot-Assisted Radical Prostatectomy
Published on: May 19, 2022
Oncologic Outcomes of Robot-Assisted Radical Cystectomy for Variant Histology Bladder Cancer: A Multi-institutional
Kimitsugu Usui1, Hiroki Ito2, Kentaro Muraoka3
1Department of Urology, Yokosuka Kyosai Hospital, Yokosuka, Japan; Department of Urology, Kanagawa Cancer Center, Yokohama, Japan.
Introduction:
Variant histology (VH) bladder cancer is characterized by aggressive biology and adverse outcomes; however, evidence in the robot-assisted radical cystectomy (RARC) era remains limited. We evaluated oncologic outcomes following RARC for VH using propensity score matching (PSM) in a multi-institutional cohort.
Patients And Methods:
We retrospectively analyzed 280 patients who underwent RARC at 5 institutions (January 2018-November 2024); 60 had VH, and 220 had pure urothelial carcinoma (PUC). Using 11 pretreatment covariates (including institution, smoking status, and comorbidities), 1:1 nearest-neighbor matching (caliper 0.10) yielded 51 matched pairs. The primary endpoint was perioperative and pathologic outcomes. Adjuvant therapy use was recorded as a descriptive measure. Disease-free (DFS), cancer-specific (CSS), and overall survival (OS) were exploratory endpoints.
Results:
Before matching, VH was associated with more advanced clinical stage and significantly worse unadjusted DFS, CSS, and OS. After expanded PSM, baseline characteristics were well balanced. The VH group retained significantly higher rates of ≥ pT3 disease (68.6% vs. 37.3%, P = .003) and transfusion (29.4% vs. 9.8%, P = .025); operative time, blood loss, complications, and hospital stay were comparable. Adjuvant therapy use was more frequent in the VH group (37.3% vs. 9.8%, P = .002). On exploratory Cox analysis, VH remained independently associated with significantly worse DFS, CSS, and OS (hazard ratios 2.3-2.8; all P < .05) after expanded adjustment.
Conclusion:
In this multi-institutional RARC cohort, after PSM for an expanded set of pretreatment clinical and comorbidity factors, perioperative outcomes other than transfusion rate were comparable between VH and PUC, supporting RARC as a feasible surgical approach for VH. However, VH retained significantly higher rates of ≥ pT3 disease, and exploratory survival analysis showed persistently worse DFS, CSS, and OS despite a greater use of adjuvant therapy, indicating that the adverse oncologic behavior of VH is not fully explained by pretreatment factors. Close postoperative surveillance and multimodal systemic therapy remain essential.