The effect of excisional biopsy on the accuracy of sentinel lymph node mapping in early stage breast cancer: comparison with core needle biopsy.

Despite the successful application of sentinel node mapping in breast cancer patients, its use in patients with a history of previous excisional biopsy of the breast tumors is a matter of controversy. In the present study we evaluated the accuracy of sentinel node biopsy in this group of patients and compared the results with those in whom the diagnosis of breast cancer was established by core needle biopsy. Eighty patients with early stage breast carcinoma were included into our study. Forty patients had a history of previous excisional biopsy and the remainder 40 had undergone core needle biopsy. Intradermal injections of 99mTc-antimony sulfide colloid as well as patent blue were both used for sentinel node mapping. Sentinel nodes were harvested during surgery with the aid of surgical gamma probe. All patients underwent standard axillary lymph node dissection subsequently. Detection rate was 97.5 per cent for both groups of the study. Number of detected sentinel node during surgery was not significantly different between groups. False negative rate was 0 per cent for both groups of the study. In conclusion sentinel node biopsy is reliable in patients with previous history of excisional biopsy of the breast tumors and has a low false negative rate.