PRIMARY EWING'S SARCOMA OF THE BLADDER ASSOCIATED WITH AN ELEVATED ANTINUCLEAR ANTIBODY TITER

Abstract

Lower urinary tract malignancy is an uncommon cause of hematuria in children. The most common pediatric bladder malignancies are rhabdomyosarcoma, leiomyosarcoma and transitional cell carcinoma. To our knowledge primary Ewing's sarcoma of the bladder has not been previously reported in any age group. We report a case of primary Ewing's sarcoma of the bladder associated with elevated antinuclear antibody titer. CASE REPORT A previously healthy 15-year-old white girl presented for evaluation of painless gross hematuria and clot urinary retention. Physical examination was normal and medical history was unremarkable. Urinalysis revealed numerous isomorphic erythrocytes but no pyuria or bacteriuria. Creatinine, serum electrolytes, liver function tests, alkaline phosphatase, lactate dehydrogenase, hematocrit and coagulation studies were normal. An antinuclear antibody titer that was obtained to rule out nephrological hematuria was elevated at 1:10,240 (normal up to 1:15). Excretory urogram showed normal kidneys and an unremarkable upper urinary tract. However, a filling defect was noted in the bladder. Cystoscopic examination revealed a 2 x 2 cm. bleeding, sessile globular tumor with focal areas of necrosis and no papillary features. The lesion was at the right anterolateral bladder wall. Transurethral resection was incomplete and biopsy specimens were not consistent with transitional cell carcinoma. Immunohistochemical and electron microscopy studies revealed small round blue malignant cells (fig. 1). Staging chest, abdomen and pelvis computerized tomography (CT) failed to reveal intra-abdominal or retroperitoneal pathology.