Halsted revisited: Internal mammary sentinel lymph node biopsy in breast cancer

Objective To investigate the feasibility of internal mammary sentinel lymph node biop sy as a method to refine and thereby improve nodal staging in breast cancer . Summary Background Data The internal mammary lymph node status is a major prognostic factor in brea st cancer. If positive, prognosis is less favorable. However, staging this regional nodal basin is not performed routinely, thus discarding additional staging information. Methods in a consecutive series of 256 patients with primary breast cancer, sentine l node biopsy was performed based on lymphoscintigraphy, intraoperative gam ma probe detection, and blue dye mapping using 10 mCi (370 MBq)Tc-99m-nanoc olloid injected peritumorally and 0.5 to 1.0 mt Patent Blue V injected intr adermally, During surgery. whenever possible, both axillary and internal ma mmary sentinel nodes were sampled. Results Lymphoscintigraphy showed axillary sentinel nodes in 95% (243/256) and addi tional internal mammary sentinel nodes in 25.3% (65/256). The overall succe ss rate of axillary sentinel node biopsy was 97% (249/256). Sampling the in ternal mammary basin, based on the results of lymphoscintigraphy, was succe ssful in 63% (41/65), In three patients a small pleural lesion resulted fro m staging this basin. This technique revealed internal mammary metastases i n 26.8% (11/41). In 7.3% (3/41), internal mammary nodes showed metastatic i nvolvement without accompanying axillary metastases. Conclusions internal mammary sentinel node biopsy is feasible without serious additiona l complications. it improves nodal staging in breast cancer by identifying higher-risk subgroups with internal mammary nodal metastases, which might b enefit from altered adjuvant treatment regimens.