Umbilical metastases: Real-world data shows abysmal outcome.

Umbilical metastases form a clinical challenge, especially when they represent the first sign of malignant disease and the primary tumor is unknown. Our study aims to generate insight into the origin and timing of umbilical metastasis, as well as patient survival, using population-based data. A nationwide review of pathology records of patients diagnosed with an umbilical metastasis between 1979 and 2015 was performed. Data was collected from the Nationwide Network and Registry of Histopathology and Cytopathology (PALGA) and the Netherlands Cancer Registry. Kaplan-Meier analyses and log-rank testing were used to estimate overall survival and a Cox proportional hazard model was used to determine multivariable hazard ratios. A total of 806 patients with an umbilical metastasis were included. There were 210 male (26.1%) and 596 female (73.9%) patients. Distribution of umbilical metastases was different between male and female patients due to the high incidence of umbilical metastases originating from the ovaries in females. They most frequently originated from the ovaries in female patients (38.8%) and from the colon in male patients (43.8%). In 18% of cases no primary tumor could be identified. Prognosis after diagnosis of an umbilical metastasis was dismal with a median survival of 7.9 months (95% confidence interval 6.7-9.1). The origin of the primary tumor was an independent prognostic factor for overall survival. In conclusion, umbilical metastases relatively rare, mainly originating from intraabdominal primary tumors. Survival is dependent on the origin of the primary tumor and poor overall survival rates warrant early recognition.