Spontaneous resolution of a 10 cm heterogenous renal lesion upon expectant management

We describe a case of a patient with a large and clinically worrisome cystic renal lesion. Despite concerning imaging features, lack of definitive enhancement on cross-sectional imaging prompted a recommendation for expected management. The unusual lesion steadily decreased in size until it nearly entirely involuted over two years of follow-up. This case highlights the importance of careful treatment calibration and adherence to established clinical principles in patients who presents with clinically concerning renal lesions that lack definitive enhancement.