Kidney Cysts is round pouches that full of watery fluid growing on kidneys. According to Bosniak Classification, five types can be divided. More often than not, most of the renal cysts are benign, while some are cancerous. Renal cysts are, generally speaking, a type called simple renal cysts. Cause of simple kidney cyst is unknown yet, but it is believed that some kind of kidney disorders may lead to the cysts. Up to 27% of individuals over 50 years old may live with simple renal cysts but with no symptoms.

Furthermore, the disease doesn't cause signs or symptoms and requires no treatment. Kidney Cysts do result in symptoms as it grows up to 10cm diameter. Signs or symptoms include dull pain in back or side, fever, or upper abdominal pain etc. The disease attacks more commonly in people over 50 years old, the incidence rate can excess 50%. Men are more prone to suffer from the disease than women.