Surgeons are routinely performing sentinel node biopsy on women with early-stage breast cancer, which may be affect the degree to which findings from ongoing trials can be generalized to broader populations, according to an article in the October 15th issue of the Journal of the National Cancer Institute.

Sentinel node biopsy is currently considered a potential alternative to standard axillary node dissection. Large trials are underway to examine the safety and accuracy of the newer procedure. However, because it is already gaining popularity, there is concern that premature adoption of sentinel node biopsy as standard care may compromise these ongoing trials.

To examine patterns of sentinel node biopsy use in U.S. comprehensive cancer centers, the researchers evaluated records for 3,003 women with stage I or stage II breast cancer who underwent sentinel biopsy alone, sentinel biopsy followed by axillary node dissection, axillary dissection alone, or no axillary surgery at 5 comprehensive cancer centers between 1997 and 2000?the period during which the procedure was entering clinical practice in the United States.

Use of sentinel node biopsy alone was associated with breast-conserving surgery. During the study period, use of sentinel biopsy alone increased over time from 8 percent in 1997 to 58 percent in the last half of 2000. There was an initial increase in the use of sentinel node biopsy plus axillary node dissection until the last half of 1999. Use of sentinel biopsy plus axillary dissection subsequently decreased as use of sentinel biopsy alone increased.

“Our data suggest that breast cancer teams at some National Cancer Institute-designated comprehensive cancer centers have weighed the currently available evidence and have accepted sentinel node biopsy as the standard of care for the treatment of breast cancer,” noted Stephen B. Edge, MD, lead author of the study. “More than a million women in the United States alone will develop invasive breast cancer before clinical trial data are available. Delaying the use of sentinel node biopsy pending trial results may lead to substantial morbidity, including permanent lymphedema in many of these women. Carefully performed clinical trials are the key to making advances in cancer care. However, other scientific evaluation methods are needed in select circumstances to prove the utility of new technologies such as new surgical procedures like sentinel node biopsy.”