Intrarenal Ectopic Adrenal Tissue Mimics Renal Cell Carcinoma in the Kidney: A Clinicopathological Diagnostic Challenge.

Background: Adrenal tissue can be found in different organs or systems of the body owing to developmental abnormalities. They may be functional or non-functional and are often discovered incidentally during imaging studies for other conditions. When located within or near the kidney, ectopic adrenal tissue can mimic renal cell carcinoma (RCC), posing a diagnostic challenge for clinicians.

Methods: We reported the case of a 65-year-old male who presented with an asymptomatic renal mass mimicking RCC on preoperative imaging. Owing to the radiological suspicion of malignancy, laparoscopic partial nephrectomy was performed to ensure appropriate management.

Results: The pathological examination of partial nephrectomy material showed findings compatible with adrenal tissue, and a diagnosis of ectopic intrarenal adrenal tissue was made. Immunohistochemical analysis confirmed the adrenal origin, with markers such as Melan-A and alpha-inhibin differentiating the lesion from RCC.

Conclusions: The ectopic location of adrenal tissue, which is usually asymptomatic and benign, complicates diagnostic and therapeutic approaches. In cases with ambiguous imaging findings, intraoperative frozen biopsy may be considered, but surgery is often preferred when malignancy cannot be ruled out. This case highlights the importance of considering ectopic adrenal tissue in the differential diagnosis of renal masses, particularly when imaging findings are inconclusive. Therefore, multidisciplinary collaboration is essential to avoid unnecessary surgical interventions and ensure optimal patient care.