[Locating the sentinel node in breast cancer by gamma probe and staining agent. Preliminary study].

OBJECTIVE: The sentinel node biopsy appears to offer an alternative to routine axillary lymph node dissection for staging patients with breast cancer. Various techniques have been studied for identifying the sentinel node, using vital blue or radioactive colloid. This study aimed to evaluate our preliminary results with these techniques.

MATERIAL AND METHODS: In this work carried out in the Valencian Institute of Oncology, 21 women with T1- T2 breast cancer with an average age of 52 years (range: 42-73) underwent the sentinel node biopsy, which was immediately followed by standard axillary dissection. Both blue dye and radioisotope were used to identify the sentinel node. The radioactive axillary of sentinel node was localized by the gamma probe.

RESULTS: The sentinel node was successfully identified by lymph node scintigraphy in 100%. It was localized by blue dye in 33% and by combination of blue dye and isotope in 95%. Of the 21 patients in this study in whom sentinel nodes were identified, 7 (35%) were histologically positive; in 6 cases, the sentinel was the only site of the metastases (86%). The histology of the sentinel node accurately predicted axillary node status in 95% of cases.

CONCLUSIONS: The sentinel node biopsy technique is a promising and feasible procedure in patients with clinically T1-T2 N0M0 breast cancer, providing valuable axillary staging information.