Urachal carcinoma initially presenting only as a liver metastasis, a diagnostic and therapeutic challenge: first case in literature.

Introduction: Urachal carcinomas are uncommon malignant neoplasms comprising only 0.01% of all adult cancers. Most patients were aged from 58 to 64 years at diagnosis with 60 years being the median. It usually metastasizes to the lungs (22%), bones (22%), and liver (16%). Presentation: We report a case of a 71-year-old female patient who initially presented with two large liver masses and a small nodule on the anterior side of the bladder. The symptoms were nonspecific with abdominal discomfort. The final diagnosis of urachal adenocarcinoma was finalized with a biopsy of the bladder mass. The patient initially received six doses of FOLFOX6 without improvement and then Gem-Carbo, showing improvement after six doses. Finally, the patient received two doses of FOLFIRI-B with no response and kept deteriorating and died after 19 months of treatment. Discussion: About 90% of patients are symptomatic and hematuria is the most typical presenting symptom at diagnosis. The low incidence and the histopathologic similarities to adenocarcinoma from various sources pose a difficulty in recognizing the tumor. Our study presents the only case of a urachal carcinoma first manifesting with abdominal mass resulting from liver metastasis with no prior symptoms of urological origins. Also, our study presents the first attempt of using FLOFIRI-B to treat metastatic UraC. Conclusion: This case highlights the necessity for clinicopathological correlation to make the correct diagnosis and the challenges in the treatment which urges the need for further research to identify more effective treatment strategies for this rare cancer.