If you don't want to clear the subjects you have failed in & want to discontinue the course work then you can definitely cancel your registration. Now the cancellation procedure from University to University. So you should visit the university & get the rules from them. On filing the formalities you will be asked to, you can cancel your registration.

Cancelling Registration is allowed by all the universities. For the procedure you have to contact your university.

I hope this answer provided you some insight. Have a great eve!