Pure large-cell neuroendocrine carcinoma of the bladder with pelvic organ invasion: A case report.

Large-cell neuroendocrine carcinoma (LCNEC) of the bladder is a rare, high-grade malignancy with aggressive behavior. We report a 69-year-old woman presenting with recurrent macroscopic hematuria. Imaging revealed a large tumor of the bladder floor involving the right ureterovesical junction, with local extension to adjacent pelvic organs but no nodal or distant metastases. Histology and immunohistochemistry confirmed pure LCNEC. She received four cycles of carboplatin-etoposide, followed by anterior pelvic exenteration with ileal conduit diversion. Postoperative recovery was uneventful, and early follow-up showed no recurrence. The case illustrates the complexity of managing locally advanced bladder LCNEC and supports individualized multimodal therapy.