What is an extra renal cyst?

Renal cysts occur within your kidneys. Extrarenal cysts occur outside your kidneys. The condition is called *extrarenal pelvis* when renal tissue collects to form a cyst that sits outside the normal anatomical parameters of a kidney.

An extrarenal cyst can be:

- A pararenal cyst is located adjacent to the kidney near the adrenal gland.

- A peripelvic cyst (also called a parapyelocalyceal cyst) lies just outside the kidney’s collecting system, which carries urine from the kidney into the bladder.

- A perinephric cyst develops in fat surrounding your kidney but is not directly attached to it.

Extrarenal cysts can also occur in the wall of the urethra, where they’re called urethral diverticula.