Neuroendocrine carcinoma in a patient with Birt-Hogg-Dubé syndrome.

Background: A patient with Birt-Hogg-Dubé syndrome (BHD) presented with gross hematuria of 6 months' duration. Imaging revealed the presence of a mass in the left prostatic lobe, in addition to a previously observed renal mass. Prostate biopsy and imaging findings indicated an inflammatory etiology, and the patient was discharged. 5 months later, the patient presented once again with urinary retention. During transurethral resection of the prostate, a mass adjacent to the bladder was observed. Postoperative imaging revealed a large pelvic mass, a second mass impinging on the rectum, and extensive lymphadenopathy. The patient died 2 weeks later.

Investigations: CT and MRI, physical examination, measurement of serum markers, urinalysis, transrectal prostate biopsy, histopathological and genetic examination of tumor specimens, postmortem immunohistochemical analysis.

Diagnosis: Neuroendocrine carcinoma of prostate or bladder origin.

Management: The patient died before planned chemotherapy or radiation therapy could be implemented. More-frequent monitoring of the patient might have led to earlier diagnosis and allowed treatment to be started before widespread tumor metastasis and invasion.