부산대학교 도서관

Synchronous occurrence of tumors in adrenal gland and pancreas is rare and is often considered as part of multiple endocrine neoplasia syndromes mainly VHL syndrome. Both pheochromocytomas and pancreatic NETs mostly occur sporadically and a small percentage are familial. We report a rare case of coexisting right adrenal interaortocaval pheochromocytoma and pancreatic neuroendocrine tumor in the absence of any familial syndrome in a 38-year-old gentleman. On evaluation for raised blood pressure, he was detected with abdominal lump on ultrasonography in December 2021. CECT abdomen showed a large well-circumscribed lobulated retroperitoneal mass epicentered in aortocaval groove compressing and displacing left renal vein with infrahepatic IVC thrombus suggestive of retroperitoneal sarcoma. Outside biopsy was suggestive of paraganglioma with raised 24-h urine metanephrines. Genetic workup with OncoPro hereditary cancer risk 98 gene panel revealed only VUS in POLD1 and PMS2 genes. DOTANOC scan showed a lobulated mass lesion 8 × 7.8 × 9.1 cm (SUVmax: 13.3) in retroperitoneal region and a SSTR expressing lesion of 1.8 × 1.5 cm (SUVmax: 52.7) in tail of pancreas not detectable on CECT scan. He was optimized preoperatively with alpha and beta blockers followed by excision of the interaortocaval mass and enucleation of the pancreatic tail NET with uneventful recovery. Histopathological examination showed right adrenal interaortocaval pheochromocytoma with pancreatic tail NET. This case shows that small neuroendocrine tumors may co-exist away from the primary site of pheochromocytoma in the absence of familial syndrome and may be missed on routine CT scan. Thus, further detailed investigation should be done to find and treat both lesions optimally in a multidisciplinary setting with surgery being the mainstay of treatment.