Advantages of one step nucleic acid amplification (OSNA) whole node assay in sentinel lymph node (SLN) analysis in breast cancer

Abstract

BackgroundThe purpose of this study is to present our first results of sentinel node analysis (SLN) by one step nucleic acid amplification (OSNA) in routine clinical practice in our centre and compare them with the results of classic histopathological analysis in a historical cohort from our same institution.Methods407 patients (total study population) with early breast cancer and no clinical nodal involvement underwent SLN biopsy in our institution. The SLN was analysed by OSNA in 164 biopsies. OSNA results were compared with the conventional histopathology study of 244 patients who had undergone SLN biopsy previously. The characteristics of the patients in both groups were evaluated and a comparison was made of the rate of metastases detected by both methods and of the surgical procedures needed in each group. We also investigated the state of non-sentinel lymph nodes if micrometastases where found in SLN.ResultsSLN biopsy result was considered as positive in 45 patients (28%) in the OSNA group and in 58 in the historical group (24%). There was no difference in the rate of macrometastases (16,5% for OSNA, 20% for HE) but we found differences in the rate of micrometastases (11% for OSNA and 3,6% for HE p = 0.0007). Axillary lymphadenectomy (ALND) was performed in 43/45 cases in the OSNA group and in 51/58 of the historical group. In all patients diagnosed by OSNA, ALND was performed during the initial surgical procedure. In the historical cohort ALND was performed during the initial surgical procedure in 41 patients and in a second surgical procedure in 10 patients. Patients from both groups with micrometastases in the SLN had no metastases in other nodes when the ALND was performed.ConclusionsOSNA analysis allows the detection of SLN metastases as precisely as conventional pathology with an increased detection of micrometastases. The OSNA method can reduce the need of a deferred lymphadenectomy.

Significance of Matrix Metalloproteinase 9 Expression as Supporting Marker to Cytokeratin 19 mRNA in Sentinel Lymph Nodes in Breast Cancer Patients

“…Ruano et al [ 24 ] also confirmed that whole lymph node examination by means of OSNA assay detects more metastases than standard histopathological study. These results were consistent with data reported by Santaballa et al [ 22 ].…”

“…Previous studies have reported that the classical histopathological analysis of SLNs significantly underestimates the axillary staging of breast carcinoma in comparison with molecular studies of SLNs by OSNA [ 8 , 22 , 23 ]. Ruano et al [ 24 ] confirmed this finding in a large study comparing the use of OSNA and histopathology for staging of axillary lymph nodes in breast cancer patients with positive SLNs.…”

Intraoperative Nomograms, Based on One-Step Nucleic Acid Amplification, for Prediction of Non-sentinel Node Metastasis and Four or More Axillary Node Metastases in Breast Cancer Patients with Sentinel Node Metastasis

“…Therefore, postoperative assessment using the FFPE LNs is preferable to the intraoperative pathological examination, although a significant proportion of patients who are assessed postoperatively as having SLN metastasis need to undergo the second surgery for cALND. However, OSNA renewed our interest in intraoperative assessment of SLNs, since OSNA has been repeatedly shown to be at least as accurate as histological examination, including immunohistochemistry, using the FFPE LNs, 21 , 22 and better than frozen section examination or imprint cytology. 21 , 23 These results point to the possibility that an intraoperative prediction model for NSLN metastasis as good as the postoperative prediction model can be constructed if OSNA is incorporated in the model.…”

Prediction of Non-Sentinel Lymph Node Metastasis by Molecular Assay in Whole Sentinel Lymph Node Analysis in Breast Cancer Patients

“…To avoid sampling errors, the concept of whole SLN analysis was reported as standard technique. 19 It also shows a quantitative result of the TTL. [22][23][24][25] Several studies have reported on significant predictive factors of additional non-SLN metastasis in patients with positive SLN who met the ACOSOG Z0011 trial but may not have completely met all the criteria of the research study.…”