Meanings
Usage patterns
案件を抱えるto have a matter/case pending
He currently has several matters on his plate.
案件を進めるto move forward with a project/deal
I don't think there's a problem continuing with this project as is.
案件を担当するto be in charge of a case/project
She is the lawyer in charge of that case.
案件を処理するto handle/process a matter
The person in charge processed all the cases.
〈人〉に案件を依頼するto request/commission a project from someone
We commissioned a new project to our business partner.
案件が発生するfor a matter/case to arise
A new issue has come up, so we need to respond right away.