Urachal cancer (UrC) is a rare disease with limited availability of representative
incidence and clinical data. Although, the prevalence is accounting for less than
1% of bladder tumors, the 5-year survival rate is around only 50% for patients with
resectable tumors, and even worse for patients with metastatic disease. Due to the
lack of comprehensive prospective studies, our current knowledge of UrC is still limited.The
present study aimed to summarize the available registry-based studies with unselected
UrC patients to evaluate its incidence and clinicopathological characteristics.We
conducted a systematic literature search of registry-based UrC publications on the
15th of May 2023 in 5 databases, which identified 4,748 publications. After duplicate
removal and selection by 2 independent investigators, 6 publications proved to be
appropriate for the final meta-analysis. Estimated incidence and clinicopathological
parameters were extracted.Estimated incidence ranged between 0.022 and 0.060/ 100.000
person-years, with the highest occurrence in Japan and the lowest in Canada, while
the random effect model calculated an overall incidence rate of 0.04 (95%CI: 0.03-0.05)
100.000 person-years. The median age at first diagnosis was 60 years (range: 58-64).
The female to male ratio was 2:3. Lymph node or distant metastases were present in
9% and 14% of patients. The predominant tumour type was adenocarcinoma (86%) followed
by urothelial carcinoma (12%) and squamous cell carcinoma (2%). The 5-year survival
rate was 51.0% with 95%CI: 45.2-57.4.Our study provides an up-to-date comparison of
estimated incidence rates between 6 countries of 3 continents based on rigorously
selected registry-based studies. The results suggest low incidence rates for UrC with
considerable geographic differences. The present meta-analysis provides unbiased registry-based
data on the incidence, clinicopathological parameters and survival of UrC.
