Bilateral diffuse uveal melanocytic proliferation (BDUMP) is a rare paraneoplastic ocular syndrome, often associated with significant vision loss and poor prognosis[1]. BDUMP is typically linked to systemic malignancies, including ovarian, lung, pancreatic, and colorectal cancers[1]. Here, we reported a case of BDUMP in a 59-year-old male patient who had been misdiagnosed with a nonfunctional adrenal adenoma. This man, with a history of diabetes mellitus and high blood pressure, complained of progressive visual loss in both eyes. He was diagnosed with BDUMP after undergoing comprehensive ophthalmic assessments at our eye center. After being referred to the urology department, he was initially diagnosed with a right nonfunctional adrenal adenoma because his renin-aldosterone levels and serum potassium levels were normal. However, three months later, the adrenal mass rapidly increased in size, and liver metastasis was confirmed. Despite normal tumor marker levels, a histopathological diagnosis ultimately confirmed adrenocortical carcinoma. This case underscores the importance of considering underlying malignancies in patients with BDUMP and highlights the necessity for early systemic evaluation, including imaging studies and multidisciplinary consultations. Timely diagnosis of underlying cancers may improve patient outcomes. It is worth noting that normal hormone levels and a tumor small-sized cannot be used as conclusive evidence that the tumor is a nonfunctional adrenal adenoma; patients with BDUMP should be closely followed up to identify the primary malignancy.
