Patterns of clinical practice for sentinel lymph node biopsy in women with node-negative breast cancer: the results of a national survey in Japan.

Purpose: Sentinel lymph node (SLN) biopsy is now accepted as the standard of care for axillary staging in women with node-negative breast cancer. Currently, dye, radioisotope (RI), and fluorescence indocyanine green (fICG) are tracers available. Importance of these three tracers has been recognized for SLN biopsy but the trend for SLN mapping has not been reported. Aim of this national wide survey was to evaluate practice patterns of SLN biopsy in Japan.

Methods: This survey was conducted to examine the clinical practice of SLN biopsy in centers where one or more Japanese Breast Cancer Society (JBCS) board-certified surgeons practice breast cancer care. Their responses were recorded from 1 to 30 Oct 2014 and received by mail or fax in Japan. The questionnaire included three items: the number of breast cancer patients treated per year, the number of SLN biopsy procedures in a single year, and the methods for SLN detection.

Results: A total of 412 responses excluding the 63 centers that do not perform the surgery were analyzed. Out of them, 206 (50 %) centers had a gamma probe, 118 (29 %) had an NIR fluorescence imaging system, and both were available at 49 (12 %) of the centers. Neither RI nor fICG was available in 137 (33 %). The dye method was preferentially used in private hospitals. In 412 centers, a total of 36,221 patients underwent SLN biopsy per year and 23,038 (64 %) received radioactive tracer. fICG was co-applied with RI in 83 and 13 % of patients, respectively. Single mapping with RI alone was used in only 4 % of patients. The non-radioactive method was used for routine SLN biopsy in 13,183 (36 %) patients [8533 (24 %) for dye alone and 4650 (12 %) for fICG alone].

Conclusions: A radioactive tracer was used in 64 % of women with early breast cancer for SLN biopsy while approximately 24 % received dye alone, which was especially prevalent in PHs. The fICG was used in only 12 % as a non-radioactive method but incentive package for fICG by national health insurance plan could increase the number of NIR imaging systems and improve the sensitivity for SLN biopsy in Japan.