Urachal carcinoma is rare, accounting for <1% of bladder neoplasms. Urachal remnants persist in and above the bladder, and urachal carcinoma may arise from any of these segments. Most are adenocarcinomas, but other histologic subtypes are described. The recommended treatment is primarily surgical, with extended partial cystectomy, en bloc excision of the urachal mass, urachal tract, and umbilicus, and a pelvic lymph node dissection. Radiation and chemotherapy are ineffective against urachal carcinoma. While some have advocated radical cystectomy as definitive therapy, this can usually be reserved for larger tumors that involve more than the upper hemisphere of the bladder.

Although most invade the bladder, urachal cancer is associated with a poor prognosis owing to advanced stage at diagnosis and extravesical tumor growth favoring local recurrence and distant metastases. Unfavorable tumor features coupled with a lack of effective chemotherapy for recurrent disease emphasize the importance of surgery as crucial for survival of nonmetastatic urachal cancer. In this report, we focus on surgical outcomes in a contemporary cohort of patients with urachal carcinoma who were treated in a consistent fashion with extended partial cystectomy and pelvic lymphadenectomy.

We operated 50 patients who presented with a presumed urachal carcinoma between 1984 and 2004. All patients were diagnosed by transurethral biopsy of a solitary tumor located at or near the dome of the bladder and staged as having nonmetastatic cancer on radiographic scans of the chest, abdomen, and pelvis. Since urachal carcinoma cannot be distinguished clinically from adenocarcinoma of the bladder dome, they were treated as urachal cancer. Each patient underwent an extended partial cystectomy together with wide en bloc resection of the entire urachus, including the umbilicus, the posterior rectus fascia and all overlying peritoneum, and perivesical soft tissue extending out to the lateral pelvic sidewalls. The superior vesical arteries were sacrificed and the upper half of the bladder above this level was removed. Wide margins of bladder were incorporated in the surgical specimen attempting to ensure removal of all tumor in the bladder wall and microscopic tumor involving perivesical fat. En bloc resection of involved adjacent organs was done when needed to remove all disease. A bilateral pelvic lymph node dissection was performed, removing at a minimum, all distal common iliac, external iliac, obturator, and hypogastric nodes. Six different surgeons performed the operations. Final pathologic stage was based on the Sheldon staging system for the primary urachal tumor; however, node status and distant metastases were considered as separate categories (1).

The end points of our study were cancer-free survival and local recurrence. Survival was defined as the time from surgery until death from urachal cancer. Patients alive at last follow-up or died of other causes were censored at that point. Local recurrence was defined as tumor recurrence within the pelvis or bladder. Associations between patient, tumor, and surgical variables were tested for their impact on survival by Pearson’s chi-square test. Kaplan-Meier survival curves were constructed and compared using the log rank test. Cox proportional hazards regression was used in a multivariate analysis for predictors of postcystectomy survival. Statistical tests were two sided and p-values <0.05 were considered significant. The Institutional Review Board approved the study.

Clinical characteristics of the 50 patients presenting with urachal carcinoma are shown in Table 55.1. The male-to-female ratio was 1.8:1. The median patient age was 50 (16-87) years. The majority of urachal tumors (88%) were high-grade adenocarcinoma. All but four urachal cancers showed local extension (stage III). Half of these were confined to the urachus and bladder (IIIA) and half invaded adjacent fat (IIIB) or extended into the peritoneal cavity (IIIC, IIID). In addition to extended partial cystectomy, resection of tumor involving colon (two cases), small bowel (one case), portion of omentum (two cases), anterior abdominal wall (one case), and peritoneal implants (one case) was also performed. Six patients (12%) had positive soft tissue surgical margins (local stage IIIB, IIIC, or IIID tumors). None of the patients had a positive bladder margin. A bilateral pelvic lymph node dissection was performed in all patients. The median number of nodes retrieved was 14 (4-34 nodes). Nodal metastases (median, three positive nodes) were found in eight (16%) patients. In two patients, despite clinically negative studies, distant metastases were found at surgery in the liver and ovary. None of the patients received adjuvant chemotherapy.

Figure 55.1 shows cancer-free survival in all 50 patients presenting with urachal cancer. Thirty-five patients (70%) survived. The median survival time was not reached with a median follow-up of 5.1 years (6.8 years for survivors and 2.2 years for patients who died of disease). Table 55.2 shows patient outcomes by clinical and tumor features. Gender, age, tumor size, histologic pattern, and tumor grade did not correlate with 5-year survival. Worse survival was associated with advanced pathologic stage, presence of nodal metastases, and positive surgical margins. Figure 55.2 shows cancer-free survival stratified by pathologic groups. Of 28 patients having tumor confined to the urachus and bladder (stage IIIA or less), 26 (93%) survived for 5 years compared with 9 of 22 (41%) having local invasion of surrounding fat (stage IIIB) or peritoneal cavity (median survival time, 2.3 years; 95% CI, 1.8-2.7 years).
Figure 55.3 shows cancer-free survival by surgical margins. Only one of six patients (17%) with a positive surgical margin survived (median survival time, 1.5 years; 95% CI, 0.86-2.1 years) compared with 34 of 44 (77%) patients who had negative surgical margins.

Nine patients (18%) had a local recurrence. These occurred in the pelvis (six cases, three invading the bladder) and bladder only (three cases) within the first 2 years of follow-up. Of the nine cases, four had negative and five had positive surgical margins (p = 0.007); four had stage ≤IIIA and five had > IIIA disease (p = 0.06). Six of the nine patients with local recurrence died, including five with pelvic recurrences, despite chemoradiation therapy. One patient recurred at the bladder neck after 2 years and was salvaged with radical cystectomy, and another developed invasive poorly differentiated carcinoma in the anterior wall of the bladder treated successfully by transurethral resection alone. A third survivor with biopsy-proven pelvic recurrence achieved a near complete radiographic response after six cycles of ifosfamide, paclitaxel, and cisplatin chemotherapy and subsequently underwent resection of a residual pelvic mass. Surgical pathology revealed no viable malignant cells. This patient is currently alive and disease free 3 years after completing chemotherapy.