Paraganglioma of urinary bladder – A rare case report

Abstract

Background: Extra-adrenal chromaffin related tumors are called Paraganglioma. These tumors constitute 18% of extra-adrenal pheochromocytomas and are exceptionally rare in the bladder accounting for < 0.06% of bladder tumors. Case Report: A 45-year-old female came with history of painless hematuria of 3 days duration. On MRI scan, she was found to have a bladder tumor arising from the posterior wall. Transurethral resection of the bladder tumor (TUR-BT) was done. During the procedure, the patient had a sudden increase in blood pressure with acute left ventricular failure and pulmonary edema. Multiple grey brown TUR-BT specimen bits on microscopy showed tumor cells in "Zellballen" pattern. These cells were round to polygonal with abundant granular cytoplasm, round, regular nuclei with stippled chromatin. Mitotic figures were seen occasionally. Immunohistochemistry for Chromogranin A showed strong positivity confirming the diagnosis to be paraganglioma of the bladder. Follow-up cystoscopy of the patient didn't show any evidence of the tumor, also her urinary and plasma vanillylmandelic acid (VMA) levels were within normal range post-operatively. Conclusion: Paraganglioma of the bladder is extremely rare. Our case presenting with only painless gross hematuria was a close mimicker of urothelial carcinoma. It has a benign coarse but has a very high recurrence rate. It is essential to differentiate it from its histological differentials for proper management and follow-up.