We report a new case of villous adenoma of the bladder associated with appendicovesical fistula treated by appendectomy along with fistula neoplasty.
Authors: Xiao, Fei; Zhang, Qian; Jin, Jie
Corresponding Author: Fei Xiao, Peking University First Hospital, Department of Urology, NO.8 Xi Shi Ku St., Xicheng District, Beijing, China. Email: [email protected]
Villous adenoma, also known as papillary tumor, is a benign tumor of glandular epithelial origin with malignant tendencies. Villous adenoma is most commonly discovered in the digestive tract, especially rectal and sigmoid colon. Reports on biliary, urinary, and genital tract villous adenomas are rare[2-4].Meanwhile, appendicovesical fistula caused by benign tumor is seldom described in the literature. We report a new case of villous adenoma of the bladder associated with appendicovesical fistula treated by appendectomy along with fistula neoplasty. A brief analysis and review of the literature is conducted.
A 41-year-old woman was admitted for recurrent mucous hematuria which lasted intermittently for 3 years. 12 months ago, upon finding a 2×1×1cm mass on the right posterior wall in the bladder during cystoscopy for the first time, she underwent a TUR-Bt procedure. Histopathology confirmed the tumor to be villous adenoma. Considering that villous adenoma of the bladder might progress to invasive adenocarcinoma, active surveillance by cystoscopy was performed every 2-3 months. 5 months later, another TUR-Bt procedure was carried out when found two tiny polypoid mass on the left anterior wall during cystoscopy with no major complaints from the patient but the same pathological conclusion. 2 months later, during the cystoscopic re-examination an appendicovesical fistula on the right wall was found. An open surgery was performed. During the operation, the appendicovesical fistula was confirmed, wedge excision of the bladder along with appendectomy and fistula neoplasty were performed. Histopathology finding of the appendix again showed villous adenoma.
At this time when the patient was admitted to our hospital, she complained of recurrent mucous hematuria with no pneumaturia or urinary tract infection present. Her symptoms started approximately 4 months after receiving appendectomy and fistula neoplasty. On physical examination, no abnormality was found. The urine appeared turbid but urinalysis was quite normal. The urine cytology was negative for malignancy. Enhanced computed tomography (CT) revealed a 2.6×3.7×3.8cm enhancing polypoid mass on the right posterior wall of the urinary bladder with tendencies of extravesical invasion (Fig.1A and 1B).
Fig.1 (A) Enhanced computed tomography (CT) revealed a 2.6 ×3.7 ×3.8cm enhancing polypoid mass on the right posterior wall of the urinary bladder. (B) Excretory phase revealed the broad-base mass with tendencies of extravesical invasion.
No other abnormalities were noted. A smooth-surfaced jel-like mass was shown on cystoscopy(Fig.2).
Fig.2 A smooth-surfaced jel-like mass was shown on cystoscopy.
No abnormality was discovered in fibrocolonoscopy(Fig.3).
Fig.3 No abnormality was discovered in fibrocolonoscopy.
We performed another TUR-Bt due to the benign character of the tumor and the patient’s intensive desire to retain the bladder. During resection of the tumor the muscular layer of the bladder wall was found to be intact. Pathology revealed the resected tumor to be villous adenoma lined by a columnar epithelium, with medium nuclear atypia but no identified invasion(Fig.4).
Fig.4 Pathology showing villous adenoma with papillary fronds lined by a columnar epithelium, with medium nuclear atypia but no identified invasion (hematoxylin and eosin stain, original magnification ×40).
Immunohistochemistry showed CK7++，CEA++，EMA++，CK20+，Ki67＞50%. The patient was suggested of further consultation every 2 months for the first year following this TUR-Bt procedure. Over the past 4 months of follow up, there has been no complaint of mucous hematuria from the patient and the latest two cystoscopy procedures showed no signs of recurrence. The patient is being followed at our clinic service, where evaluation for further treatment can be carried out when necessary.
Villous adenoma of bladder was first described by Assor in 1978. Based on the origin of the adenoma, cases can be divided into two categories, primary and secondary. Primary villous adenoma of the bladder is rare, with no more than 20 individual cases reviewed in the English literature. Secondary villous adenoma of the bladder is more commonly seen in the direct invasion of intestinal adenomas, especially the cecum and vermiform appendix. Primary and secondary villous adenoma of the bladder have similar characteristics in histology, pathology and clinical manifestations, leading to some difficulty in differential diagnosis.
Primary villous adenoma of the bladder have relatively satisfactory prognosis according to limited individual case reports[3, 6,7]. This patient had undergone two TUR-Bt procedures and open surgery of appendectomy along with fistula neoplasty, suggesting her villous adenomas of the bladder might be secondary due to appendicovesical fistula.
The most common cause of Appendicovesical fistula is appendicitis. Cecal diverticulitis, cystadenocarcinoma or carcinoid tumours of appendix are other known causes. There is a total of over 100 cases of appendicovesical fistula published in the English literature, characterized by pneumaturia and recurrent urinary tract infection. CT and cystoscopy are helpful in diagnosing and planning for therapy. Currently only 3 cases of Appendicovesical fistula caused by benign tumors are reported in published literatures. Lund reported a case with pneumaturia and recurrent urinary-tract infection, the only pathological finding was the presence of abundant amount of nervous tissue in the appendix, which was considered as benign neurofibroma. Timmermans[9, 10] reported two cases of appendicovesical fistula caused by papillo-villous adenoma of the appendix, suggesting that complete surgical resection is curative.
To sum up, for secondary villous adenoma of the bladder, especially those with appendicovesical fistula, open surgery is needed. Appendectomy along with fistula neoplasty rather than radical right hemicolectomy or radical cystectomy would theoretically achieve a cure. This would benefit both the patient’s prognosis and quality of life.
Nevertheless, Certain rate of recurrence does exist, different therapeutic approaches (TUR-Bt or radical cystectomy) should be carefully selected according to the pathological results of biopsy and the patient’s will. Considering that villous adenoma of the bladder might progress to invasive adenocarcinoma, close surveillance is strongly recommended after TUR-Bt. More aggressive treatments may be indicated when iterative recurrence occurs or discovers invasive adenocarcinoma.
We report a new case of villous adenoma of the bladder associated with appendicovesical fistula treated by appendectomy along with fistula neoplasty. Considering the diagnosing and treating process of the tumor, we classified this villous adenoma of the bladder as secondary due to appendicovesical fistula. It is the fourth known case of Appendicovesical fistula caused by benign tumors. Another TUR-Bt was preformed due to the benign character of the tumor and the patient’s intensive desire. Pathology revealed the resected tumor to be villous adenoma with medium nuclear atypia but no identified invasion. Close surveillance is strictly performed considering that villous adenoma of the bladder might progress to invasive adenocarcinoma.
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Date added to bjui.org: 30/08/2011