[Validation of sentinel node in breast cancer].
BACKGROUND
The sentinel lymph node biopsy in breast cancer can be used instead of axillary dissection when the node is negative because the sentinel lymph node (SLN) represents the first node that receive lymphatic drainage and may predict the tumor status of the entire lymph node group, so it may avoid a more morbid procedure. The objective of this study was to determinate the accuracy of this procedure and to evaluate techniques using blue dye, radiocolloid or both.


METHODS
Sixty-one women underwent sentinel lymphadenectomy followed by axillary lymph node dissection. Thirty-one patients underwent breast conserving surgery and 30 modified radical mastectomy. We studied three groups of patients: the first group was injected with isosulfan blue dye, the second group was injected with technetium-99m-labeled sulfur colloid and the third received both. From the patients marked with isosulfan blue, twenty two patients were injected subareolar (43.2%) and 29% into the breast parenchyma immediately surrounding the primary tumor or biopsy cavity (56.8%). Technetium-99m-labeled sulfur colloid was injected into the breast parenchyma immediately surrounding the primary tumor. Standard axillary lymphadenectomy including level I and level II was performed in all patients. Statistical analysis was performed with the SPSS 10.0 statistical software. Significance was considered at p < 0.05.


RESULTS
At least one SLN was identified in all patients (100%). The SLN predicted the tumor status of the entire lymph node group in 59 patients (96.77%). There were two false negative sentinel nodes (3.3%), each one using isosulfan blue dye injected subareolar and surrounding a primary tumor. The mean number of SLNs removed were 1.06 in the group 1, 2.2 in the group 2 and 2.37 in the group 3 (p = 0.0001 for group 1 vs. 2 and 3). The sensitivity and negative predictive value were 91 and 95%, respectively.


CONCLUSIONS
This procedure has enough accuracy to justify avoidamce of standard axillary lymphadenectomy when the sentinel node is negative for me- tastases. Both isosulfan blue dye injected techniques may be used indistinctly. When the radiocolloid technique is used there are an increase in the mean number of SLNs removed per patient.
Vergara-Fernández
Omar
O
Dirección de Cirugía, Servicio de Cirugía Oncológica, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México, DF.
Cortés-González
Rubén
R
Medina-Franco
Heriberto
H
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*