Pheochromocytomas are rare neuroendocrine tumors arising from chromaffin cells of the adrenal medulla. Malignancy is defined by the presence of distant metastases. Approximately a substantial proportion are associated with germline mutations, particularly in the context of Von Hippel-Lindau (VHL) syndrome. We report the case of a 60-year-old man diagnosed with a clinically silent locally advanced pheochromocytoma following a computed tomography-guided biopsy of a left retroperitoneal mass discovered during evaluation for persistent lower back pain. Biochemical evaluation revealed normal 24-hour urinary metanephrines despite markedly elevated chromogranin A levels. Imaging demonstrated an 80 × 76 mm left adrenal mass with locoregional invasion. Histopathological and immunohistochemical analyses confirmed pheochromocytoma. 123I-metaiodobenzylguanidine scintigraphy showed increased uptake in the adrenal region. Genetic testing identified a pathogenic VHL mutation: NM₀00551. 4 (VHL): c. 508G>A, consistent with VHL type 2C phenotype. Systematic screening for other VHL-associated lesions was negative. This case highlights the diagnostic challenge posed by clinically silent pheochromocytomas and underscores the importance of genetic evaluation in atypical adrenal tumors.
Eddebbarh et al. (Mon,) studied this question.