Can the Multiple entry Visitor Visa be cancelled if Green Card is applied

[rajesh101]

Hi,

My father is in Mumbai and currently has a 10 year Multiple entry visa.
He has also visited US few times in past.

I would like to apply for his green card, so he can come to US permanently.

If I apply from here, would his Visitor visa be cancelled?
Or can he still use his visitor visa to come to US if needed, till his Green card application is pending.

Thanks ....