Most times a core biopsy test result comes back to you within 2 to 3 days if the lab is not very busy.
Sometimes the lab that does the core biopsy test results may be very busy testing many other core biopsies as well as other tests and it can take 7 to 10 days in some cases to get the test results back from core biopsy tests.
That is true also if the test results need to have more analysis done to it before they send the test results back to you.
If you haven't heard back from the doctor within 10 days then you should call the doctor to find out about the test results.
I've had the test results from my core biopsy come back within 4 days but other test results have taken as long as 12 days because the lab was busy and backed up with many tests.