Cancel a pre-approved purchase order

We are on 11i with all extended support patches in place.

Before I completed all of the steps for a service/expense PO one buyer entered a PO that came up pre-approved. Once saved he clicked on the approval process and now the PO is stuck in the workflow as pre-approved and we cannot receive on it nor can we cancel it. We would like to cancel it but the only control item that is in the list is On Hold. Because it is still an active PO it continues to show up in our reports as waiting receipt.

Are there any ideas on how I can cancel or delete this order?