Factores predictivos de alta carga residual ganglionar axilar post biopsia de ganglio centinela positiva / Predictive factors of high residual burden in axillary lymph node after positive sentinel node biopsy

El estado axilar es un factor pronóstico para los estadios tempranos de cáncer de mama. Existen factores que podrían predecir riesgo de mayor enfermedad axilar. El objetivo es determinar cuáles son los factores predictivos independientes de alta carga residual ganglionar axilar (4 o más GNC comprometidos) luego de la BGC positiva. Estudio analítico, observacional, cohorte retrospectiva de pacientes con tumores T1-2, axila clínicamente negativa, a las que se les realizó cirugía conservadora (CC) y BGC con resultado positivo (marco o micrometástasis) y se les realizó posterior linfadenectomía axilar (LA). Del total de 325 pacientes, 96 tuvieron resultado positivo para metástasis en el ganglio centinela (29,5%) y también se les realizó LA. Se dividió a la población seleccionada en dos grupos según el compromiso de los GNC: baja carga axilar 0-3 GNC positivos, y alta carga axilar 4 o más GNC positivos. Se observaron como factores que demostraron mayor riesgo para alta carga axilar ganglionar residual al grado histológico, ki-67 y la invasión extracapsular en el GC; pero solamente la invasión extracapsular en el GC demostró ser significativa en el análisis multivariado. Probablemente con un mayor número de pacientes otras variables pudieran haber resultado factores de riesgo independiente

Axillary status is a prognostic factor for early stages of breast cáncer. There are predictive factors that might indicate the risk of greater axilary disease. The aim is to determine which are the independent predictive factor sor a high residual axillary nodal burden (four or more non-sentinel lymph nodes involved) after a positive sentinel node biopsy. Retrospective cohort analytic observational study of patients with T1-2 tumors, negative axilla, who underwent breast conserving surgery and sentinel node biopsy with a positive result (macro ­ or micro-metastasis) and later underwent lymph node dissection. Out of the total 325 patients, 96 got a positive result for metástasis in the sentinel lymph node (29.5%) and also underwent lymph node dissection. The selected population was divided into two groups according to the involvement of NSLNs: low axillary burden: 0-3 NSLNs, and high axillary burden: 4 or more positive NSLNs. Among the factors found to have a higher risk of high residual axillary nodal burden were the histologic grade, Ki-67 and the extracapsular invasión of the SLN, but only the extracapsular invasión of the SLN was found to be significant in the multivariate analysis. It is likely that with a higher number of patients, other variables might have been independent risk factors

Sentinel Lymph Node in Breast Cancer: Review Article from a Pathologist's Point of View

Breast cancer staging, in particular N-stage changed most significantly due to the advanced technique of sentinel lymph node biopsy two decades ago. Pathologists have more thoroughly examined and scrutinized sentinel lymph node and found increased number of small volume metastases. While pathologists use the strict criteria from the Tumor Lymph Node Metastasis (TNM) Classification, studies have shown poor reproducibility in the application of American Joint Committee on Cancer and International Union Against Cancer/TNM guidelines for sentinel lymph node classification in breast cancer. In this review article, a brief history of TNM with a focus on N-stage is described, followed by innate problems with the guidelines, and why pathologists may have difficulties in assessing lymph node metastases uniformly. Finally, clinical significance of isolated tumor cells, micrometastasis, and macrometastasis is described by reviewing historical retrospective data and significant prospective clinical trials.

Analysis of the Clinicopathological Features in the Micrometastasis and the Macrometastasis in Sentinel Lymph Node of Primary Breast Cancer

PURPOSE: The aim of this study was to compare the micrometastasis group with the macrometastasis group, and to analyze clinical and pathological variables to determine what factors might predict non-sentinel lymph node (NSLN) involvement in the women with sentinel nodes that contained only micrometastasis. METHODS: Between June 2003 and September 2005, 650 patients with primary breast cancer and who underwent a SLN procedure were retrospectively reviewed. Of those 650 patients, 138 patients with metastasis in the SLNs were analyzed. RESULTS: The median number of harvested sentinel lymph nodes (SLNs) was 2.5 (range: 1~7) and the median number of tumor positive LNs was 2.1 (range: 1~22). Of the 138 patients with a positive SLN, macrometastasis was identified in 105 patients and micrometastasis was noted in 33 patients. The SLN micrometastases were smaller than 0.2 mm in 18 patients and it was between 0.2 to 2.0 mm in 15 patients. Completion axillary dissection was performed in 17 (51.5%) patients with SLN micrometastasis and in 105 (100%) patients with SLN macrometastasis. NSLN involvement was found in 43/105 (41.0%) patients with SLN macrometastasis, while it was not found in the patients with SLN micrometastasis. Univariate analysis showed that T stage, multiplicity, lymphovascular invasion and histologic type were significantly associated with the difference between micrometastasis and macrometastasis in the SLNs. Multivariate analysis identified T stage as a significant factor. CONCLUSION: This study suggests that NSLN metastasis is associated with size of metastasis found in the SLN and completion axillary dissection may not be necessary in patients who have micrometastatic disease in the SLN.