Adrenal cyst misdiagnosed with cystic renal cell carcinoma: A case report.

Adrenal cysts are rare adrenal masses that are typically benign and are often incidentally discovered during imaging examinations. However, their complex imaging characteristics can lead to misdiagnosis, particularly when they closely adhere to the upper pole of the kidney, thus resembling renal cysts or cystic renal cell carcinoma (RCC). The present study describes the case of a 41-year-old male patient who presented with left flank pain and was initially diagnosed with a left renal cyst. Imaging examinations identified a simple renal cyst at the upper pole of the left kidney closely adhering to the left adrenal gland. The patient underwent posterior retroperitoneoscopic left renal cyst decortication and subsequent histopathological examination revealed clear cells lining the cyst wall, indicative of low-grade clear cell RCC. Due to the discrepancy between the clinical and radiological findings and the pathology report, a multidisciplinary team was convened. An expert pathological consultation was recommended, which resulted in a revised diagnosis of an adrenal cyst. The present study highlights the diagnostic challenges in distinguishing adrenal cysts from renal cysts and RCC by imaging and histopathology. The present study also underscores the need for multidisciplinary collaboration and thorough pathological evaluation, including the use of appropriate immunohistochemical staining, to avoid misdiagnosis.