Archbishop Andre-Mutien Leonard said "a feeling of anger and powerlessness" had taken hold of the church.
He said that the crisis gripping the church was so deep that it would be impossible to find an easy way out.
The report listed 507 witnesses who came forward with stories of abuse at the hands of clergy over decades.
It said those abused included children who were two, four, five and six years old.
Family members or friends said 13 victims committed suicide that "was related to sexual abuse by clergy," the report said.
Six other witnesses said they had attempted suicide.