Low axillary sampling in clinically node-negative operable breast cancer.

ABSTRACT

Background. Targeted sentinel node biopsy has been extensively validated. It has been incorporated into standard guidelines for axillary prediction in women with clinically node-negative operable breast cancer. However, the high cost of the gamma probe and the need for radiocolloid have limited its widespread acceptance in developing countries. We aimed to validate low axillary sampling as a reliable alternative method to sentinel node biopsy in a developing country. Methods. An anatomically guided low axillary sampling removes the lower level I axillary fat with lymph nodes and the method was validated by completing axillary clearance in all women. Results. Three hundred fifty-five women with clinically node-negative operable breast cancer underwent validation of low axillary sampling, with lymph nodes identified in all of them. The median number of nodes identified in low axillary sampling was 5 with overall node-positivity of 32.1% (114 of 355). Ten of these 114 patients were wrongly identified as node-negative by the sampled lymph nodes, i.e. a false-negative rate of 8.8%. Further exploratory analysis showed that 6-node low axillary sampling gave an excellent false-negative rate of 1.5% with 95% sensitivity, which was comparable with the highly targeted sentinel node biopsy technique. Conclusions. With an overall false-negative rate of 8.8% with 5-node low axillary sampling, and even better falsenegative rate of 1.5% with 6-node low axillary sampling, axillary sampling is a low-cost technology, which is a reliable alternative to sentinel node biopsy for axillary nodal prediction in clinically node-negative breast cancer.