Saudi Journal of Kidney Diseases and Transplantation

LETTER TO THE EDITOR
Year
: 2011  |  Volume : 22  |  Issue : 6  |  Page : 1256--1258

Urachal mucinous cystadenoma


Sudipta Saha, Ashesh Jha, Sanjay Gupta 
 Department of Surgery, University College of Medical Sciences and GTB Hospital, University of Delhi, Delhi, India

Correspondence Address:
Sudipta Saha
Department of Surgery, University College of Medical Sciences and GTB Hospital, University of Delhi, Delhi
India




How to cite this article:
Saha S, Jha A, Gupta S. Urachal mucinous cystadenoma.Saudi J Kidney Dis Transpl 2011;22:1256-1258


How to cite this URL:
Saha S, Jha A, Gupta S. Urachal mucinous cystadenoma. Saudi J Kidney Dis Transpl [serial online] 2011 [cited 2019 Dec 9 ];22:1256-1258
Available from: http://www.sjkdt.org/text.asp?2011/22/6/1256/87249


Full Text

To the Editor,

The urachus is an embryological structure extending from the umbilicus to the urinary bladder apex and it uncommonly persists in adults. [1] Sometimes the urachus can be the primary site of benign and malignant neoplasms. Urachal adenocarcinomas account for 20-39% of primary urinary bladder adenocarcinomas, which in turn account for 0.17-0.34% of all bladder malignancies. [2] Even rarer than urachal adenocarcinomas are urachal adenomas which may coexist with in situ and invasive adenocarcinoma. [3],[4] Despite being benign, urachal mucinous tumors have the potential to behave in an aggressive clinical manner that includes the development of pseudomyxoma peritonei. [5],[6]

We would like to share our experience with a 60-year-old lady who presented with symptoms of increased frequency of urine for three months. It was not associated with dysuria, fever, or hematuria. Urine routine microscopy was within normal limits. Ultrasonography of the abdomen was done which revealed a 3 × 3 cm cystic lesion in the prevesical region. A subsequent rigid cystoscopy demonstrated an extrinsic compression at the bladder dome, but there was no mucosal lesion. Magnetic resonance imaging (MRI) demonstrated a 3 × 3 smooth well defined mass anterior to the urinary bladder [Figure 1]. The mass was indenting the bladder, but there was a clear plane between the mass and the bladder. With the provisional diagnosis of urachal cyst, the patient underwent surgical excision. During operation, a well rounded 3 × 3 cm cystic lesion was found in the space of retzius anterior to the dome of the urinary bladder [Figure 2].{Figure 1}{Figure 2}

The mass was well separated from the bladder and excision of the cyst was easily accomplished.

The cross section of the lesion revealed smooth cyst wall and presence of mucinous fluid. Histopathology of the specimen revealed mucinous cystadenoma. The cyst was lined by glandular epithelium that lacked pseudostratified and villous area. There were no foci of dysplasia or adenocarcinoma in situ. The mucin of the cyst was hypocellular without any atypical epithelial cells. The patient had an uneventful recovery. Two years after the operation, she is well without any recurrence.

The urachus is a vestigial structure located between the dome of the bladder and the umbilicus. In the fetus, the urachus connects the bladder with the allantois. In normal development, the allantois is gradually reduced and obliterated and the urachus becomes a fibrous band extending from the anterior bladder dome to the umbilicus.

Urachal tumors usually remain undiscovered for a long period because of their obscured location. They can be found incidentally or at an advanced stage. The pathogenesis of urachal tumors is not fully understood. It is believed that urachal carcinomas arise from malignant transformation of columnar or glandular metaplastic epithelium. They lie in the space of Retzius, between transversalis fascia anteriorly and peritoneum posteriorly, extending from the dome of the bladder to the umbilicus. The presence of urachal remnants predispose to its formation and prophylactic excision of benign urachal lesions has been recommended. [7]

Urachal cystadenoma is a rarely reported pathologic condition that can cause a palpable mass and abdominal pain. The term mucinous tumor of uncertain malignant potential has been suggested for urachal mucinous tumor without frank invasion, as they have a potential for local recurrence and development of pseudomyxoma peritonei. [8] The differential diagnosis of a urachal mucinous cystadenoma of undetermined malignant potential includes villous adenoma, urachal adenocarcinoma, urothelial malignancy with an adenocarcinoma component, and metastatic disease from a variety of sites, including the breasts, ovaries, gastrointestinal tract and prostate gland. [3]

References

1Eble JN. Abnormalities of the urachus. In: Young RH, ed. Pathology of the urinary bladder. New York: Churchill Livingstone; 1989. p. 213-43.
2Sheldon CA, Clayman RV, Gonzalez R, Williams RD, Fraley EE. Malignant urachal lesions. J Urol 1984;131(1):1-8.
3Cheng L, Montironi R, Bostwick DG. Villous adenoma of the urinary tract: a report of 23 cases, including 8 with coexistent adenocarcinoma. Am J Surg Pathol 1999;23(7):764-71.
4Seibel JL, Prasad S, Weiss RE, Bancila E, Epstein JI. Villous adenoma of the urinary tract: a lesion frequently associated with malignancy. Hum Pathol 2002;33(2):236-41.
5de Bree E, Witkamp A, Van De Vijver M, Zoetmulde F. Unusual origins of pseudomyxoma peritonei. J Surg Oncol 2000; 75(4): 270-4.
6Mendeloff J, McSwain NE Jr. Pseudomyxoma peritonei due to mucinous adenocarcinoma of the urachus. South Med J 1971;64(4):497-8.
7Schell AJ, Nickel CJ, Isotalo PA. Complex mucinous cystadenoma of undetermined malignant potential of the urachus. Can Urol Assoc J 2009;3(4):39-41.
8Carr NJ, McLean AD. A mucinous tumour of the urachus: adenoma or low grade mucinous cystic tumour of uncertain malignant potential? Adv Clin Pathol 2001;5(3):93-7.