Frozen Section Biopsy and Nephron-Sparing Surgery for a Multiloculated Cyst of the Kidney; Is this the Ideal Approach?

Multiloculated cystic renal masses are uncommon in the pediatric population. The presentation may be as an asymptomatic incidental finding on imaging, abdominal mass, abdominal pain, or urinary tract infection. The differentiation between benign and malignant causes of a cystic lesion by clinical and radiological examination is difficult. Tru-cut biopsy is not recommended due to fear of upgrading a malignant tumor. A definitive diagnosis is confirmed histopathologically only after surgery. Based on certain imaging characteristics, benign nature can be suspected and a conservative approach to surgery can be contemplated to save the kidney. Frozen section biopsy is useful in ruling out malignancy while doing nephron-sparing surgery (NSS) in these patients. NSS may be done by an open or minimally invasive approach. After histological confirmation of cystic nephroma, no other adjuvant treatment is necessary, but long-term surveillance is strongly recommended.