Spontaneous remission of untreated primary amyloidosis of the bladder after transurethral resection biopsy: a case report and literature review.

We herein present a case involving a 23-year-old woman with gross hematuria. Cystoscopy revealed abnormal areas of the mucosa along the anterior and posterior bladder walls. These abnormalities were suspicious for neoplasia; however, a diagnosis was not established by subsequent biopsy. The patient underwent transurethral resection biopsy in which an isolated lesion along the anterior wall was completely resected and the others were left untreated. Pathologic examination and special staining led to a diagnosis of amyloidosis, and the patient elected to undergo transurethral surgery 1 month later. During the operation, the intravesical lesions were found to have significantly improved in both the treated and untreated sites. The operation was cancelled, follow-up was arranged, and no other treatment was administered. Repeat cystoscopy examinations at 3 and 9 months after surgery showed that the lesions had almost completely disappeared.