Anterior wall adenocarcinoma of bladder with similar clinicopathological and prognostic characteristics as common bladder carcinomas should not be treated as or classified into urachal adenocarcinomas

Abstract Purpose To discuss whether the dome or anterior wall of bladder adenocarcinoma (BAC) should be classified into urachal carcinoma (UrC) and the relationship of primary tumor location (PTL) as well as treatment with survival. Methods Surveillance, Epidemiology, and End Results 18 database was examined for eligible patients from 1975 to 2016. Patients were classified into adenocarcinoma originating from the urachus (UAC), the dome (D‐BAC), the anterior wall (A‐BAC), and the other sites adenocarcinoma of the bladder (O‐BAC). The clinicopathological features, treatment, and survival were compared among the groups. Results Comparable clinicopathologic features were obtained between UAC and D‐BAC, which were different from those of A‐BAC and O‐BAC; otherwise, the latter two had similar clinicopathologic features. Univariable and multivariable Cox regression analyses indicated that PTL was an independent predictor for survival. O‐BAC conferred the worst prognosis then followed by A‐BAC, D‐BAC, and UAC. For non‐metastatic UAC or D‐BAC, partial cystectomy (with an en bloc resection of the urachus and umbilicus) is optimal for survival. However, the worse survival of non‐metastatic D‐BAC (compared with UAC) suggested different modalities, maybe more intensive surgery approaches, should be considered for D‐BAC. Conclusion This study illustrates that PTL of UAC and BAC was an independent predictor for survival. A‐BAC had comparable characters and prognosis with O‐BAC and should not be classified into and treated as UrC. For non‐metastatic disease, non‐metastatic D‐BAC may need more intensive modality