If you ever need to cancel your account you will first need to log in to your account then press the settings/gear icon
A smaller page will show you more setting options, general settings will take you to the setting page for your entire account.
At the bottom of the User Settings page, there is an option to delete your account in red.
After selecting the delete account option, you will see how many profiles are being removed including the number of releases under each profile. If you agree to the removals of the artist profiles and releases then you can select "Delete" in the bottom right corner to finalize the removal.