Non-conservative management of simple Renal cysts IN adults: A comprehensive review of literature

INTRODUCTION: Renal cysts are common findings in nearly 10% of general population. According to Bosniak classification, they are classified into simple and complex renal cysts based on their CT characteristics. The majority of simple renal cysts are asymptomatic and require no intervention. Once they become symptomatic or complicated, a nonconservative management should be considered. EVIDENCE ACQUISITION: This paper is a narrative review of existing manuscripts regarding the non-conservative management of renal cysts. To perform it a search through PubMed was carried out in January 2017. The search was conducted using the following key words: "simple renal cysts," "non-conservative management," "treatment outcomes comparison" etc. EVIDENCE SYNTHESIS: We found 1880 publications that were reviewed by 2 of our authors, and only 46 manuscripts were considered for this review. The most common treatment were investigated and compared to understand the best treatment modality in accordance with patients' and cysts' characteristics. Different treatment modalities are available for the management of simple renal cysts. Surgical exploration is a historical procedure that is no longer used. Simple aspiration without sclerotherapy has high recurrence rate (20-80%), so sclerosants agents are recommended. Ethanol is the most commonly used sclerosing agent with high efficacy up to 97%. Laparoscopy is the gold standard for management in large cysts especially in younger patients. Other techniques are described for parapelvic renal cysts like percutaneous endoscopic ablation and ureteroscopic marsupialization. CONCLUSIONS: Different factors affect the treatment decision including natural history of the cyst, presence of symptoms and/or complications and patients' choice. This literature overview shows that ethanol percutaneous sclerotherapy and laparoscopy are the most commonly reported treatment modality for simple renal cysts.