The ASCO Health Services and Technology Committee has done an excellent job of providing a comprehensive review of the available evidence to date regarding lymphatic mapping and sentinel lymph node biopsy in breast cancer patients. Lyman et al are to be congratulated for their extensive analyses. My commentary will address progress related to the selection of patients and the performance of lymphatic mapping in breast cancer patients.

The pace at which cancer centers adopted SLND was documented nicely by Edge et al3 in their review of more than 3,000 early-stage breast cancer patients treated at the five original participants of the National Comprehensive Cancer Network (NCCN) between 1997 and 2000. During this time frame, the proportion of stage I breast conservation therapy patients undergoing SLND as the only axillary staging procedure increased from 8% to 58%.

Epidemiology, and End Results (SEER) Program for early-stage breast cancer patients treated between 1998 and 2000. Although SLND rates increased from 13.5% of cases in 1998 to 36.4% in 2000, there were notable disparities in demographics for the patient populations that had access to this technology. Lymphatic mapping rates were relatively higher on the East and West Coasts (22% to 33%) compared with Alaska, Iowa, and Utah (8% to 18%).