A case of tubular adenoma developing after bladder augmentation: Case report and literature review

We encountered a rare case of tubular adenoma developing after bladder augmentation. We here report our case as well as summarize reports in the literature on adenomas developing after bladder augmentation.

A 23-year-old man came to our hospital for routine surveillance cystoscopy. He was born with a lipomyelomeningocele and neurogenic bladder with low bladder compliance, and hence his bladder was routinely emptied by clean intermittent catheterization. He was also treated with anticholinergic agents. However, because the patient's neurogenic bladder was unstable, he underwent sigmoidocolocystoplasty when he was 8-years old. After the bladder augmentation, he was examined annually by surveillance cystoscopy. On cystoscopy, a 5-mm pedunculated polyp was found on the front side of the sigmoid colon cap. Therefore, we performed snare polypectomy together with electrocoagulation under cystoscopy. The patient's final diagnosis was tubular adenoma (mild atypia) with no malignancy, as assessed by histopathology. There has been no evidence of recurrence after the polypectomy on routine surveillance cystoscopy.

To the best of our knowledge, there have been 11 cases of adenoma occurring after bladder augmentation reported in the literature, including our present case. There are several carcinogenic pathways associated with colorectal oncogenesis. Adenomas that are larger than 1.0cm in diameter with a marked villous component have a high risk of oncogenesis.

We believe that the early detection of carcinoma or adenoma and their treatment at an early stage is crucial. Therefore, we recommend routine surveillance cystoscopy for patients after bladder augmentation.