Malignant urachal lesions.

Urachal cancers are uncommon malignancies with a location that often permits considerable local extension before they are discovered. The most common histological type is adenocarcinoma, which may produce mucus that is a valuable aid in diagnosis. The presence of stippled calcification in a midline abdominal wall mass is almost pathognomonic for urachal carcinoma. More commonly, however, the symptoms are less specific, such as hematuria and an abdominal mass. Many lesions are visible endoscopically and, thus, the diagnosis can be made preoperatively from a biopsy. Most treatment failures occur because the tumor is not controlled locally by the initial operation and, therefore, we recommend en bloc cystectomy with umbilectomy and pelvic lymphadenectomy unless the tumor is known to be a sarcoma or early stage (I) carcinoma. If these patients are undertreated and there is a local recurrence then the patient usually is not salvageable. Because of the difficulty in identifying the origin of a bladder adenocarcinoma, any tumor on the dome or anterior wall should be approached initially as if it were a urachal tumor.