Robot-Assisted Partial Cystectomy versus Open Partial Cystectomy for Patients with Urachal Cancer.

INTRODUCTION: Localized urachal cancer (UrC) can be treated with an open partial cystectomy (OPC) with en bloc resection of the urachal remnant and umbilicus. Robot-assisted partial cystectomy (RAPC) is an alternative approach, of which its safety and efficacy for UrC remains to be determined. In the present study, we analyze these outcomes after RAPC, compared with OPC. METHODS: We retrospectively evaluated 55 cN0M0 UrC patients who underwent RAPC (n = 8) or OPC (n = 47) between 1994 and 2020. Overall survival (OS) and recurrence-free survival (RFS) were assessed using Kaplan-Meier methods. Positive surgical margins (PSM), port-site recurrences (PSR) versus wound recurrences were compared. Complications were recorded using the Clavien-Dindo classification. RESULTS: Median follow-up was 40 months (IQR 21-95). Two-year OS and RFS for RAPC were 73% (95% confidence intervals (CI); 56-89 months) and 60% (95% CI; 42-78 months), respectively, versus 90% (95% CI; 85-95 months) and 66% (95% CI; 59-73 months) for OPC. PSM rate was 13% in both groups. PSR occurred in 2/8 (25%) patients after RAPC. No wound recurrences occurred after OPC. Postoperative complications occurred in 2/8 (25%) patients after RAPC, versus 5/47 (11%) after OPC (p = 0.27). CONCLUSION: Both RAPC and OPC seem feasible surgical modalities to treat localized UrC with comparable survival. The PSR rate of 25% after RAPC should prompt us to be cautious to recommend RAPC as no such recurrences were seen using OPC.

Diagnostic Laparoscopy and Abdominal Cytology Reliably Detect Peritoneal Metastases in Patients with Urachal Adenocarcinoma.

BACKGROUND: Urachal adenocarcinoma (UrAC) is a rare malignancy that can cause peritoneal metastases (PM). Analogous to other enteric malignancies, selected patients with limited PM of UrAC can be treated by cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). OBJECTIVE: The aim of this study was to address the value of diagnostic laparoscopy (DLS) and abdominal cytology (ACyt) for the detection and evaluation of the extent of PM in patients with UrAC. METHODS: A consecutive series of cN0M0 patients with UrAC who underwent DLS with or without ACyt at a tertiary referral center between 2000 and 2018 was assessed. Patients were staged with computed tomography (CT) and/or positron emission tomography (PET)/CT or bone scan. DLS was performed to rule out PM and to evaluate the extent and resectability of PM if seen on imaging. Sensitivity and specificity values were calculated for imaging, DLS, ACyt, and the combination of DLS and ACyt. RESULTS: Thirty-two patients with UrAC underwent DLS. ACyt was obtained in 19 patients. Four patients had suspicion of PM on imaging. In the 28 patients who were PM-negative on imaging, DLS and ACyt revealed PM in 6 (21%) patients, of whom 5 had macroscopically visible PM; 1 patient had positive ACyt without visible PM. Sensitivity of combined DLS/ACyt for the detection of PM was 91%, with a specificity of 100%, whereas sensitivity of imaging was 36%. DLS correctly predicted resectability in all patients. CONCLUSION: Combined DLS/ACyt proved an effective tool to detect occult PM and to evaluate the extent of PM to select UrAC patients for possible treatment with CRS/HIPEC.

Clinical value of preoperative serum tumor markers CEA, CA19-9, CA125, and CA15-3 in surgically treated urachal cancer.

INTRODUCTION: Urachal adenocarcinoma (UrAC) is a very rare malignancy with a poor prognosis. The role of preoperative serum tumor markers (STMs) in UrAC is unknown. The aim of this study was to assess the clinical value of elevated STMs including carcinoembryonic antigen (CEA), cancer antigen 19-9 (CA19-9), cancer antigen 125 (CA125), and cancer antigen 15-3 (CA15-3) in surgically treated UrAC, and to evaluate their prognostic significance. METHODS: This was a retrospective study of consecutive patients with histopathologically confirmed UrAC who underwent surgical treatment at a single tertiary hospital. Blood levels of CEA, CA19-9, CA125, and CA15-3 were determined before surgery. The proportion of patients with elevated STMs was calculated, as well as the association between elevated STMs and clinicopathological characteristics, recurrence-free survival and disease-specific survival. RESULTS: Of the 50 patients included; CEA, CA 19-9, CA125, and CA15-3 were elevated in 40%, 25%, 26%, and 6% respectively. Elevated CEA was associated with higher pT-stage (odds ratio [OR] 3.3 [95% confidence interval 1.0-11.1], P = 0.003), higher Sheldon stage (OR 6.9 [95% CI 0.8-60.4], P = 0.01), male sex (OR 4.7 [95% CI 1.2-18.3], P = 0.01), and the presence of peritoneal metastases at the time of diagnosis (OR 3.5 [95% CI 0.9-14.2], P = 0.04). Elevated CA19-9 was associated with signet-cell component (OR 1.7 [95% CI 0.9-3.3], P = 0.03) and elevated CA125 was associated with peritoneal metastases at the time of diagnosis (OR 6.0 [95% CI 1.2-30.6], P = 0.04). Elevated STMs before surgery were not associated with recurrence-free survival and/or disease-specific survival. CONCLUSION: A subset of patients with surgically treated UrAC has elevated STMs preoperatively. CEA was most frequently (40%) elevated and correlated with unfavorable tumor characteristics. However, STM levels did not correlate with prognostic outcomes.

Two Patients with Urachal Cancer with Multifocal Adenocarcinoma Recurrences in the Urothelium of the Prostatic and Penile Urethra.

We report two cases with recurrences of urachal adenocarcinoma (UrAC) in the urethra. Both patients had mucinous UrAC without metastasis, for which they were treated with en-bloc partial cystectomy and umbilectomy. The first patient developed recurrence of UrAC in the distal urethra after 1 yr. Distal urethrectomy revealed multiple additional recurrences in the penile and prostatic urethra. The patient underwent radical cystoprostatectomy with en-bloc urethrectomy. At 5 mo after surgery, liver metastases were found. A search in our institutional database revealed a second patient who developed a solitary recurrence of UrAC in the prostatic urethra 8 yr after partial cystectomy. Radical cystoprostatectomy was performed. The patient subsequently experienced recurring UrAC in the urethra, which were treated with multiple surgeries and radiation. Unfortunately, local tumor control could not be achieved and the patient developed distant metastases 7 yr after cystoprostatectomy. Our two cases and four comparable cases reported in the literature indicate that urothelial spread of UrAC is rare but possible. It remains to be determined if UrAC spreads along the urothelium similar to urothelial cancer or if these multifocal urethral recurrences were the first sign of local metastasis.

The Diagnostic Value of FDG-PET/CT for Urachal Cancer.

BACKGROUND: Urachal carcinoma (UrC) is a rare malignancy that often presents at an advanced stage with metastases in up to a quarter of patients. There is no consensus on the optimal form of staging for patients with UrC. In the present study, we evaluated the diagnostic value of 18F-fluorodeoxyglucose-positron emitted tomography/computed tomography (FDG-PET/CT) for UrC. PATIENTS AND METHODS: We evaluated 40 consecutive patients who were staged for urachal cancer between 2010 and 2020. They underwent a total of 62 FDG-PET/CTs (40 for primary staging, and 22 during follow-up), which were compared with standard-of-care contrast-enhanced CT (CECT). The metabolic detection of primary tumors, lymph node metastases (LNMs), peritoneal metastases (PMs), distant metastases (DMs), and local recurrence by FDG-PET/CT was evaluated. Sensitivity and specificity were calculated compared with CECT. Histopathology or follow-up imaging was the reference standard. RESULTS: Of all 40 patients, 33 patients (83%) had urachal adenocarcinoma-26 (65%) with a mucinous component and 7 (17%) with invasive urothelial carcinoma. All local UrC tumors could be visualized on CT, and 80% showed increased FDG uptake. At initial staging, FDG-PET/CT detected FDG-avid LNMs, PMs, and DMs in 50%, 17%, and 25% of patients, respectively. These metastases were also visualized on CECT. During follow up, FDG-PET/CT revealed FDG-avid local recurrences that were not seen on CT in two out of eight patients (25%). CONCLUSION: The present study demonstrates that most UrC can be visualized on FDG-PET/CT. At initial diagnosis, FDG-PET/CT does not seem to yield additional information compared with CECT; however, FDG-PET/CT may be helpful during follow-up. This is a small study, and the findings should be corroborated with larger series.