Amyloid deposits can be localized as a wall thickness or mass lesion either as AA amyloidosis or AL amyloidosis and may develop nearly on all organs. It is generally a mild, non–life-threatening entity with a good prognosis and rarely showed progression to systemic disease

We present two cases of urinary bladder localized AL amyloidosis that presents with painless hematuria and imaging studies mimic malignant tumors. Cystoscopic evaluation and biopsy were performed.

63 years male presents with massive hematuria. Ultrasonography revealed a 17 × 14mm mass lesion on the bladder wall. Transurethral biopsy specimen histology showed lambda-type amyloid. The second patient was a 71-year-old male and evaluation for painless hematuria revealed a bladder wall mass lesion whose histology was consistent again with AL amyloidosis. Both patients did not have systemic amyloidosis signs and symptoms

The literature did not include long-term outcomes. Usually, benign nature was depicted, and surgical removal is the preferred treatment. Since the contributing factors are not clear, we are concerned about the risk of recurrence and experienced the challenge of anti-plasma cell therapy giving or not.