Unusual presentation of high-grade neuroendocrine carcinoma of the Urinary bladder with small-cell and large-cell features.

High-grade neuroendocrine carcinoma of the urinary bladder comprehends small-cell and large-cell variants. It is a rare and aggressive neoplasm, mostly diagnosed in advanced stages. It is more frequently encountered among Caucasian men in the sixth decade of life. Urinary symptoms are the most common clinical presentation. Diagnosis is generally not troublesome once the lesions are easily detectable by imaging exams and cystoscopy. This neoplasia is associated with tobacco smoking, and is frequently associated with other carcinomatous components such as urothelial carcinoma, adenocarcinoma, and sarcomatoid carcinoma. The authors report a case of an apparently healthy female patient who presented cervical lymph node enlargement not accompanied by systemic symptoms. The supraclavicular lymph node biopsy revealed metastatic small cell carcinoma. The computed tomography scan showed a bladder wall nodular thickening, enlarged lymph nodes along the iliac, periaortic, mediastinal, cervical and supraclavicular chains, as well as an insufflating lytic bone lesion in the right iliac wing. The positron emission tomography-fluorodeoxyglucose (PET-FDG) added to these findings, the presence of a paraesophageal lymph node, lymphadenomegaly in the gluteal region and a vertebral lytic lesion in T10. Resected specimen of the bladder tumor revealed a high-grade neuroendocrine carcinoma with small-cell and large-cell features.