Mucinous adenocarcinoma of the kidney is a very rare malignancy, frequently originating from the renal pelvis. Its cystic appearance often resembles benign conditions such as hydronephrosis or renal cysts, complicating preoperative diagnosis. We present a 57-year-old male with a 20-year history of recurrent bilateral nephrolithiasis with left upper abdominal distension, vague discomfort, and dyspeptic symptoms. Imaging revealed a severely hydronephrotic, non-functioning left kidney with cortical thinning and multiple calculi. A percutaneous nephrostomy was attempted but failed to provide effective drainage of the mucopurulent material. Due to poor renal function and persistent drainage, a left nephrectomy was performed. Histopathology demonstrated mucin-producing atypical columnar epithelium, consistent with mucinous adenocarcinoma. Mucinous adenocarcinoma of the kidney is difficult to differentiate from hydronephrosis or renal cysts based solely on imaging. Early suspicion and surgical management are essential for appropriate treatment and favorable outcomes.
Şenoğlu et al. (Sun,) studied this question.