Urachal carcinoma (UrC) is a rare malignancy, and patients with this disease have a poor prognosis. In this article, the authors report 50 years of experience with this tumor at the Mayo Clinic.

A urachal mass was described in 130 patients, and 66 of those masses were malignant. The authors identified multivariate predictors of malignancy in clinically diagnosed urachal masses and predictors of UrC-specific survival. This report presents a novel 4-category staging system for UrC along with the treatment history of this tumor and the results of salvage therapy.

Twenty women and 46 men were identified with UrC. The strongest predictors of malignancy in a urachal mass were hematuria and age older than 55 years. The 5-year cancer-specific survival rate was 49%. The new Mayo staging system was less complicated than the Sheldon system, although both systems predicted cancer-specific mortality equally well. Positive surgical margins (hazard ratio [HR], 4.7), high tumor grade (HR, 3.6), positive local lymph nodes (HR, 5.1), metastases at diagnosis (HR, 3.3), advanced tumor stage (HR, 4.8), failure to perform umbilectomy (HR, 3.0), and primary radiation therapy (HR, 2.9) were all univariately associated with death (P <.05). Only grade and margins were significant in the multivariate analysis. No survival benefit was noted for lymphadenectomy or adjuvant therapy. Salvage surgery resulted in a long-term cure for 50% of patients who had local recurrences. No effective treatment was identified for patients with metastatic UrC.

Early and complete extended partial cystectomy, including umbilectomy, is critical to the survival of patients with UrC. The authors recommend using the Mayo staging system in future studies because of its simplicity. The current results indicated that the most important predictors of prognosis were tumor grade and surgical margin status.