Core Biopsy Reliability

[Jordan9]

How reliable are core biopsies as compared to excisional biopsies?  I concerned about a false-negative if I have a core biopsy, but of course would like to avoid an excisional biopsy if I could do so safely.  I wasn't sure how the two tests compared in this way.  Thanks very much.

[divan]

In my core needle biopsy, tissue was sampled from 5-6 different areas.  More reliable than sample of only one area where cells could have died off. Each tissue sample is sufficient size to cut and biopsy.

[Cleveland Clinic]

Dear Jordan9:  Core biopsy takes a sample (sometimes more than one) of the area of concern.  The size of the sample is the size of the core needle.  It is hoped that this sample will represent the rest of the area of concern.  In many cases the results of the core biopsy are adequate to describe the abnormality.  Sometimes, there is concern that the sample may not be representative or there are features that suggest that there could be additional issues with the rest of the abnormality.  In these cases, an excisional biopsy may be recommended.  If there is concern that a core will not provide the information needed, an excisional biopsy may be recommended