Incidence and survival in patients with urachal carcinoma: Cancer registry analysis between 2008 and 2019.

480 Background: Urachal carcinoma (UrC) is a rare and poorly studied cancer without evidence-based treatment strategies. Due to the low prevalence of this cancer, only sparse data on its incidence and survival are available. Therefore, we analyzed the incidence and survival rates of patients with UrC in North Rhine-Westphalia (NRW), a state of the Federal Republic of Germany. Methods: UrC (ICD-O-3: C67.7) diagnosed between 2008 and 2019 were identified via the NRW Cancer Registry (population 18 million) and classified according to Mayo-staging and T-category. Mayo stage was based on the TNM classification. We calculated age-standardized incidence rates using the European standard and Kaplan-Meier overall survival (OS). Age was stated as mean and standard deviation (SD). Results: A total of 121 UrC patients were described, of which men were more frequently affected at 57%. The distribution for women was 43%. The mean age was 61.1 (SD: 15.5) years for men and 58.8 (SD: 15.3) years for women. The overall age-standardized incidence rate was 0.43 per 1.000.000 person-years, which was 0.5 for men and 0.37 for women. 85.1% had adenocarcinomas, 6.6% urothelial carcinoma, 4.1% unspecified cancer, 2.5% epithelial carcinomas, 0.8% squamous cell carcinomas or others, respectively. The 5-year OS rate were 60.4% (CI-95%: 48.9%; 74.7%) for men and 41.7% (CI-95%: 28.8%; 60.2%) for women. According to TNM classification, 33% of the patients presented with T1-2, 29.8% with T3-4, while for the Mayo staging a distribution of 17.4% for stage I-II and 13.2% for stage III-IV was shown. Data regarding T-category and Mayo-satging were available in 63.6% (44 patients) and 30.6% (84 patients), respectively. The 5-year OS was 73.3% (CI-95%: 59.3%; 90.6%) in T1-2, 37.2% (CI-95%: 23.6%; 58.6%) in T3-4. and 69.3% (CI-95%: 47.6%; 100%) and 25.6% (CI-95%: 9.89%; 66.49%) in Mayo stage I-II and III-IV, respectively. Conclusions: UrC is a rare cancer and OS rate in NRW were comparable to historical data. The prognosis was stage-dependent and identified poor outcome in patients with advanced disease. Our data underscored the role of proper staging and diagnosis for future clinical studies that investigate optimal treatment strategies.