Waiting for biopsy results

After 3 weeks having biopsy from a large polyp found during a colonoscopy i decided to ring and see what was happening.  Was told no results as yet and are taking up to 3 months.   How can this be right?  I spoke to the consultants secretary and she put me through to the nurse s secretary.   How can they make you wait 3 months to see if the polyp was cancerous.