Urachal Mucinous Cystic Tumour of Low Malignant Potential: A Case Report With Literature Review.

Urachal mucinous cystic tumours of low malignant potential (MCTLPs) are exceedingly rare epithelial tumours. MCTLPs arise from the remnants of the urachus and are characterised by the presence of intestinal-type mucinous epithelium with low-grade cytologic atypia without stromal invasion, which differentiates them from mucinous adenocarcinomas. These tumours are often asymptomatic and found incidentally on imaging done for other reasons; symptoms, however, may include mild abdominal pain/discomfort, storage lower urinary tract symptoms (LUTS) or mucusuria. The treatment is surgical excision, which carries favourable cure rates. We hereby present a case of a 38-year-old man who had an incidental finding of an intravesical cystic lesion on ultrasound done as part of the work-up for newly diagnosed hypertension. The only symptom the patient described in hindsight was an occasional discharge of a gelatinous material in his urine. His work-up also included a diagnostic flexible cystoscopy and a computerised tomography (CT) scan with a delayed urographic phase, which confirmed the finding of a urachal cyst. Histopathological examination following surgical excision confirmed the presence of a rare low-grade urachal MCTLP.