Case Report

138 Urology Journal    Vol 7    No 2    Spring 2010

Mucinous Adenocarcinoma of the Urachal Remnant 
with Pseudomyxoma Peritonei
Benjamin w Lamb, Ram Vaidyanathan, Marc Laniado, Omer Karim, Hanif Motiwala

Urol J. 2010;7:138-9.
www.uj.unrc.ir

Keywords: urachus, 
adenocarcinoma, pseudomyxoma 

peritonei

Department of Urology, Wexham 
Park Hospital, UK

Corresponding Author:
Benjamin Lamb, MD

54 Cyprus Avenue, London, N3 
1SR, UK

Tel: +44 783 011 9301
Fax: +44 207 281 0446

E-mail: benwlamb@googlemail.com

Received March 2009
Accepted October 2009

INTRODUCTION
We report a rare case of urachal 
carcinoma causing pseudomyxoma 
peritonei (PMP) in a patient who 
presented with symptoms of 
chronic urinary retention. It is very 
unusual for urachal carcinoma to 
present in this way.

CASE REPORT
A 63-year-old man presented 
with suprapubic pain, terminal 
dribbling, a suprapubic mass, and 
microscopic hematuria. Flexible 
cystoscopy showed a mass in the 
dome of the bladder (Figure 1). 
Magnetic resonance imaging 
revealed a cystic mass in the dome 
of the bladder, but separated from 
the bladder with fluid, debris, and 
nodularity within the abdomen and 
the pelvis. The patient underwent 

laparotomy, where extensive PMP 
was discovered. Thereafter, he 
underwent partial cystectomy, 
omentectomy with excision of the 
tumor.

Histological examination revealed 
mucinous adenocarcinoma of the 
urachal remnant with metastases 
to the omentum (Figures 2 and 3). 
The patient underwent further 
debulking of the tumor with 
limited peritonectomy. At 18 
months follow-up, recurrence 
occurred in the liver and the patient 
underwent further resection.

DISCUSSION
Urachal carcinoma is a rare 
neoplasm, accounting for 0.01% 
of all malignancies and 0.34% of 
the bladder carcinomas.(1,2) Urachal 
carcinoma is usually seen in male 

Figure 1. Cystoscopy showing tumor bulging into dome of the 
bladder.

Figure 2. Low power view of section of the bladder showing 
the interface between the normal bladder wall on the left and 
Urachal carcinoma on the right.



Pseudomyxoma Peritonei in Urachal Carcinoma—Lamb et al

139Urology Journal    Vol 7    No 2    Spring 2010

patients between 40 and 70 years of age. (3) The 
prognosis is poor; the tumor produces few 
symptoms until it is advanced. About 95% of 
patients have muscle invasion or metastatic cancer 
at the time of diagnosis.(4) Typically, the cancer 
spreads locally to the abdominal wall, and the 
peritoneum.(1,2) Although histological analysis 
reveals mucin production in about 75% of cases, 
mucinuria occurs in about 25% of patients.(5) The 
radiographic finding of supravesical calcification 
associated with a bladder lesion is pathognomonic 
for urachal adenocarcinoma.(3)

Pseudomyxoma peritonei is characterized by 
dissecting gelatinous ascites and peritoneal 
implants secreting copious amounts of 
extracellular mucin. Pseudomyxoma peritonei 
causes scalloping of the margins of the abdominal 
viscera, with septation of fluid collection with or 
without calcification. Progressive disease of the 
peritoneal cavity and compression of abdominal 
viscera are common, leading to wasting and 
repeated bowel obstruction.

Urachal carcinoma is almost uniformly resistant 
to chemotherapy or radiotherapy. Treatment 
for urachal carcinoma is surgical, usually en bloc 
radical cystoprostatectomy with wide excision 
of the urachus and umbilicus. Partial cystectomy 
with urachectomy can be as effective as more 
radical excision and causes less morbidity (5-year 
overall survival rate of 43%).(3,5)

This case highlights a rare presentation of urachal 
carcinoma with PMP in a patient with bladder 
outflow obstruction. It is a difficult tumor to treat 
and generally has a poor prognosis. Although 
there is little literature on the subject, some 
reports of less radical surgery suggest reduced 
morbidity with effective oncological results.

ACKNOwLEDGEMENTS
The authors would like to thank Dr Hatyam 
Sheriff, Consultant Pathologist, Wexham Park 
Hospital, Slough.

CONFLICT OF INTEREST
None declared.

REFERENCES
1. Ravi R, Shrivastava BR, Chandrasekhar GM, 

Prahlad S, Balasubramanian KV, Mallikarjuna VS. 
Adenocarcinoma of the urachus. J Surg Oncol. 
1992;50:201-3.

2. Chow YC, Lin wC, Tzen CY, Chow YK, Lo KY. 
Squamous cell carcinoma of the urachus. J Urol. 
2000;163:903-4.

3. Yu JS, Kim Kw, Lee HJ, Lee YJ, Yoon CS, Kim MJ. 
Urachal remnant diseases: spectrum of CT and US 
findings. Radiographics. 2001;21:451-61.

4. Cooperman LR. Carcinoma of urachus with extensive 
abdominal calcification. Urology. 1978;12:614-6.

5. Sheldon CA, Clayman RV, Gonzalez R, williams 
RD, Fraley EE. Malignant urachal lesions. J Urol. 
1984;131:1-8.

Figure 3. High power view of a slide showing nests of mucinous 
adenocarcinoma cells. Note the large quantities of extracellular 
mucin.