Functional paraganglioma, an uncommon cause of seminoma metastasis, diagnostic and therapeutic management.

We report a 62-year-old male, with history of uncontrolled hypertension (3 drugs) in who, it was found an incidentally left retroperitoneal hypervascular tumor (5.7 x 3.5 cm) in the CT. It was demonstrated contact between tumor and left renal artery and ureter, without regional lymphadenopathy. The patient was asymptomatic, but had increased of norepinephrine (1141.1 pg/mL), epinephrine (93.3 pg/mL) and serotonin blood levels (264.1 g/L). The MRI confirm the tumor, with serotonin affinity in the 68Galium-Edotreotide PET/CT (DOTATATE) but not in the MIBG/Scan. Therefore, a paraganglioma was the suspected diagnosis. Tumor board recommended excision, due to the risk of being a functional paraganglioma. The tumor was resected through laparoscopic approach after alpha-beta-adrenergic blockade. Postoperatively, hypertension and norepinephrine blood levels were normalized. The histological report surprisingly showed a Seminoma (positivity for PLAP, OCT ¾, c-kit, MDM2) and the surgical margins were free.