Results of Preoperative Lymphoscintigraphy for Breast Cancer Are Predictive of Identification of Axillary Sentinel Lymph Nodes

The aim of this study was to identify the variables associated with successful peroperative sentinel lymph node (SLN) localization. We studied 201 patients with T1, T2, N0 invasive breast cancer who underwent a SLN procedure from 1999 to 2003. Of these 201 patients, 55 underwent peritumoral and 146 underwent periareolar radioisotope injection before the blue dye injection. All patients were operated on by breast conservative surgery and axillary dissection after SLN biopsy. Age, weight, menopausal status, previous biopsy, localization of the tumor, results of lymphoscintigraphy, site of radiotracer injection, tumor size, tumor grade, experience of surgeons, and the number of invaded axillary nodes were analyzed to determine whether they had any significant correlation with successful identification of SLN. Variables found to have a statistically significant influence on the SLN identification rate and on preoperative lymphoscintigraphy identification were introduced into a univariate and multivariate logistic regression model. In multivariate analysis, successful lymphoscintigraphy (P < 0.0001) and the absence of metastatic axillary nodes (P < 0.005) were associated with successful identification of SLNs. The peritumoral injection of radiotracer (P < 0.001), patient age > 60 years (P < 0.003), and localization of the tumor in the upper outer quadrant (P < 0.004) were associated with failure of lymphoscintigraphic visualization of SLN. The technique of SLN detection thus appears to be better for patients with low risk of invaded axillary lymph nodes.