A Rare Case of Non-Functional Adrenocortical Oncocytic Neoplasm Presenting as a Left Flank Pain

Abstract

Introduction: Adrenocortical oncocytic neoplasms (AONs) are rare tumors of the adrenal cortex characterized by oncocytic histology. Due to their rarity, variable malignant potential, and nonspecific clinical presentation, preoperative diagnosis remains challenging. Case Presentation: A 38-year-old female presented with left flank pain to Orthopedics OPD for which Contrast-enhanced computed tomography was done. It revealed a large, well-defined left adrenal mass without evidence of invasion. After which she was referred to Urology OPD for further management. Clinical evaluation and hormonal workup suggested a non-functioning adrenal tumor. The patient underwent open left adrenalectomy. Histopathological examination confirmed an adrenocortical oncocytic neoplasm of uncertain malignant potential based on Lin–Weiss–Bisceglia criteria. The postoperative period was uneventful, and the patient remains disease-free on follow-up. Conclusion: AONs are rare adrenal tumors that may present with mass effect rather than hormonal symptoms. Complete surgical excision is the treatment of choice. Long-term follow-up is essential due to unpredictable biological behavior.