One-step nucleic acid amplification assay for intraoperative prediction of advanced axillary lymph node metastases in breast cancer patients with sentinel lymph node metastasis

Can axillary lymphadenectomy be avoided in breast cancer with positive sentinel lymph node biopsy? Predictors of non-sentinel lymph node metastasis

PURPOSE

Completion axillary lymph node dissection (cALND) can currently be avoided in those patients with a low tumor load (LTL) and/or a low-risk profile that tested with positive sentinel lymph node biopsy (SLNB). Our objective is to identify prognostic factors that significantly influence axillary lymph node involvement to identify patients who could benefit from surgery without axillary lymphadenectomy.

METHODS

This is an observational retrospective study of consecutive patients diagnosed and operated of breast cancer between 2000 and 2014 at University Hospital La Ribera (UHR).

RESULTS

The size of the sample was 1641 patients, from which 1174 underwent SLNB. In the multivariate analysis, we objectify a raise of risk of positive sentinel lymph node (SLN) up to 5.2% for every millimeter of increase. The risk of positive SLNB when showing lymphovascular invasion seems to be 2.80 times greater but becomes lower when SLN involvement appears in luminal A, luminal B and triple-negative types, regarding HER2. In case of triple negatives, the difference is statistically significant. 16.7% present affected additional lymph nodes. The proportion of patients with affected additional lymph nodes increase dramatically above OSNA values of 12,000 copies/μl of CK19 mRNA and it depends on tumor size and lymphovascular infiltration.

CONCLUSIONS

Tumors smaller than 5 cm whose OSNA SLNB analysis is less than 12,000 copies/μl of CK19 mRNA have a low chance to develop additional affected lymph nodes, thus cALND can be avoided.

One-step nucleic acid amplification CK19 copy number for sentinel node biopsy in breast cancer: Identification of new cutoffs to predict nonsentinel axillary node involvement

We evaluated novel sentinel node values in breast cancer for one-step nucleic acid amplification (OSNA) to predict further nodal involvement using various methods in clinically node-negative disease with a positive OSNA result and subsequent axillary node dissection. 239 patients (118 macrometastatic) were assessed revealing cutoffs of total tumor load (TTL) 44 500 copies/µL (AUROC 0.793); average copy number (ACN) 9450 (AUROC 0.790); and highest copy number (HCN) 46,000. For macrometastatic patients only: TTL 221 400 copies/µL (AUROC 0.685); ACN 64,000 (AUROC 0.671); HCN 59 500 (AUROC 0.529). Our data favor TTL and represent one of the largest OSNA macrometastatic predictive series.

External validation of a prognostic model based on total tumor load of sentinel lymph node for early breast cancer patients

Background

A prognostic model based on the results of molecular analysis of sentinel lymph nodes (SLN) is needed to replace the information that staging the entire axilla provided. The aim of the study is to conduct an external validation of a previously developed model for the prediction of 5-year DFS in a group of breast cancer patients that had undergone SLN biopsy assessed by the One Step Nucleic Acid Amplification (OSNA) method.

Methods

We collected retrospective data of 889 patients with breast cancer, who had not received systemic treatment before surgery, and who underwent SLN biopsy and evaluation of all SLN by OSNA. The discrimination ability of the model was assessed by the area under the ROC curve (AUC ROC), and its calibration by comparing 5-years DFS Kaplan–Meier estimates in quartile groups of model predicted probabilities (MPP).

Results

The AUC ROC ranged from 0.78 (at 2 years) to 0.73 (at 5 years) in the training set, and from 0.78 to 0.71, respectively, in the validation set. The MPP allowed to distinguish four groups of patients with heterogeneous DFS (log-rank test p < 0.0001). In the highest risk group, the HR were 6.04 [95% CI 2.70, 13.48] in the training set and 4.79 [2.310, 9.93] in the validation set.

Conclusions

The model for the prediction of 5-year DFS was successfully validated using the most stringent form of validation, in centers different from those involved in the development of the model. The external validation of the model confirms its utility for the prediction of 5-year DFS and the usefulness of the TTL value as a prognostic variable.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05623-4) contains supplementary material, which is available to authorized users.

Sentinel node total tumour load as a predictive factor for non-sentinel node status in early breast cancer patients - The porttle study

OSNA is a molecular assay for the detection of sentinel node metastasis. TTL emerged as a concept that seems to accurately predict the status of the NSN. Authors tried to confirm this motion. This is a retrospective and multicentric study that analyzed 2164 patients, 579 of whom had positive SN and completion AD. Logistic regression models were performed in order to identify a suitable cutoff to identify patients who benefit from AD. Univariate and multivariate regression analysis showed a relationship between TTL>30000 and the presence of NSN metastasis (OR 2.84, CI 1.99-4.08, p < 0.001). Logistic regression indicated that the cutoff of 30000 copies/μL better discriminates patients with NSN positivity and allows wide use of these criteria. This cutoff value may safely assist clinicians and patients to decide to proceed or not with an AD.

Nomogram to predict non-sentinel lymph node status using total tumor load determined by one-step nucleic acid amplification: first report from Thailand

BACKGROUND

Axillary staging is a significant prognostic factor often used to determine the treatment course for breast cancer. One-step nucleic acid amplification (OSNA) is now the most accepted method for intra-operative assessment of sentinel lymph nodes (SLN) as it can semi-quantitatively determine the tumor burden in these SLN. Axillary lymph node dissection (ALND) may be omitted in patients with limited disease in the axilla. The objective was to create nomogram for prediction of non-sentinel lymph node (NSLN) status using OSNA to avoid unnecessary ALND.

PATIENTS AND METHODS

Patients with invasive breast cancer T1-T3 and clinically negative axillary lymph nodes underwent SLN biopsy assessed by OSNA. The patients with positive SLN underwent ALND. Correlations between total tumor load (TTL), clinicopathological parameters, and NSLN status were analyzed by Chi square statistic and logistic regression. Model discrimination was evaluated using receiver-operating characteristic (ROC) analysis.

RESULTS

The total number of patients who underwent SLN biopsies was 278. There were 89 patients with positive SLN. NSLNs were positive in 40 patients. Larger tumor size, presence of lymphovascular invasion (LVI) and higher log TTL were independent factors that predicted positive NSLN. TTL can discriminate NSLN status with area under the ROC curve of 0.789 (95% CI 0.686-0.892). Two nomograms using different parameters obtained pre- and post-operatively can predict NSLN involvement with better area under the ROC curve (0.801, 95% CI 0.702-0.900 and 0.849, 95% CI 0.766-0.932, respectively).

CONCLUSIONS

Nomograms using results obtained via OSNA can predict NSLN status, as well as aid in deciding to omit the use of ALND.

One-step nucleic acid amplification: the possible value in assessing sentinel lymph node metastasis during mastectomy

Breast cancer is the most common cancer in women, worldwide, and 1,400 deaths per day are attributed to it. The success of national screening programs has seen breast cancers being diagnosed at an earlier stage. With conservative surgery to the breast demonstrating equivalent long-term outcomes, the last 10 years have seen a growing interest in the safety of less invasive management for the axilla in breast cancer patients. One-step nucleic acid amplification (OSNA) is a validated, reliable, and efficient tool in identifying micro- and macro-metastases intraoperatively. It is the most widely used intraoperative analysis tool within the United Kingdom, and is employed by over 320 units across Europe and Asia. Recent evidence from the AMAROS, IBCSG 23-01, and ACOSOG Z0011 trials has changed surgical practice in managing the axilla of patients with breast cancer. We propose a clinical algorithm demonstrating the role of OSNA as an intraoperative analysis tool in today's management of breast cancer as well as prospects for the future use of OSNA.

Comparison of CK-IHC assay on serial frozen sections, the OSNA assay, and in combination for intraoperative evaluation of SLN metastases in breast cancer

BACKGROUND

Intraoperative evaluations of sentinel lymph node (SLN) metastases are performed for providing appropriate and immediate axillary treatments in breast cancer patients who do not meet Z0011 criteria; however, standard intraoperative procedure has not yet been established.

METHODS

We consecutively performed intraoperative evaluation for SLN metastases using both a cytokeratin immunohistochemistry (CK-IHC) assay on serial frozen sections and a one-step nucleic acid amplification (OSNA) assay of the remaining whole node in patients with invasive breast cancer. In this article, we compared the intraoperative diagnostic ability of CK-IHC assay, the OSNA assay, and in combination.

RESULTS

Between August 2009 and May 2017, 1,103 SLNs from 499 consecutive clinically node-negative invasive breast cancers were intraoperatively evaluated for SLN metastases using an OSNA and CK-IHC assay. The detection rates of SLN metastases by the OSNA and CK-IHC assays and in combination were 11.8, 12.1, and 14.5%, respectively. The concordance rate between the intraoperative SLN findings of the OSNA and CK-IHC assays was 94.9% (95% confidence interval 93.6-96.2%). The false negative rate for the OSNA assay was 3.1% (30/973), including 3 (0.3%) macrometastases and 27 (2.8%) micrometastases, and for the CK-IHC assay was 2.7% (26/969), including 1 (0.1%) OSNA ++ and 25 (2.6%) OSNA +.

CONCLUSIONS

The CK-IHC assay and the OSNA assay have compatible diagnostic abilities in intraoperative evaluations for SLN metastases. The low incidence of false negative results with limited disease burden suggests that both assays can be reliable techniques for intraoperative diagnoses of SLN metastases in breast cancer patients.

Intraoperative prediction of the two axillary lymph node macrometastases threshold in patients with breast cancer using a one-step nucleic acid cytokeratin-19 amplification assay

The aim of the present study was to assess the sensitivity, specificity and practicality of using a one-step nucleic acid amplification (OSNA) assay during breast cancer staging surgery to predict and discriminate between at least 2 involved nodes and more than 2 involved nodes and facilitate the decision to provide axillary conservation in the presence of a low total axillary node tumour burden. A total of 700 consecutive patients, not treated with neo-adjuvant chemotherapy, received intraoperative sentinel lymph node (SLN) analysis using OSNA for cT1-T3 cN0 invasive breast cancer. Patients with at least one macrometastasis on whole-node SLN analysis underwent axillary lymph node dissection (ALND). The total tumour load (TTL) of the macrometastatic SLN sample was compared with the non-sentinel lymph node (NSLN) status of the ALND specimen using routine histological assessment. In total, 122/683 patients (17.9%) were found to have an OSNA TTL indicative of macrometastasis. In addition, 45/122 (37%) patients had NSLN metastases on ALND with a total positive lymph node burden exceeding the American College of Surgeons Oncology Group Z0011 trial threshold of two macrometastatic nodes. The TTL negative predictive value was 0.975 [95% confidence interval (CI), 0.962-0.988]. The area under the curve for the receiver operating characteristic curve was 0.86 (95% CI, 0.81-0.91), indicating that SLN TTL was associated with the prediction (and partitioning) of total axillary disease burden. OSNA identifies a TTL threshold value where, in the presence of involved SLNs, ALND may be avoided. This technique offers objective confidence in adopting conservative management of the axilla in patients with SLN macrometastases.

Clinical significance of MSKCC nomogram on guiding the application of touch imprint cytology and frozen section in intraoperative assessment of breast sentinel lymph nodes

The widely practiced intra-operative methods for rapid evaluation and detection of sentinel lymph node (SLN) status include frozen section (FS) and touch imprint cytology (TIC). This study optimized the use of TIC and FS in the intra-operative detection of breast SLNs based on the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram. Three hundred forty-two SLNs were removed from 79 patients. SLN metastatic probability was assessed by the MSKCC nomogram. The SLNs underwent intra-operative TIC and FS, as well as routine post-operative paraffin sections (RPSs). The relationships between TIC, FS, and SLN metastatic probability were analyzed. Overall, TIC was more sensitive than FS (92.31% vs. 76.92%), while TIC specificity was inferior to FS specificity (84.85% vs. 100%). In addition, the best cut-off value for TIC based on the MSKCC nomogram was inferior to the best FS cut-off value (22.5% vs. 34.5%). All patients with a MSKCC value <22.5% in the present study were negative based on FS and RPS, while the true-negative and false-positive rates for TIC were 92.5% and 7.5%, respectively. Thus, early breast cancer patients, based on a MSKCC value <22.5%, can safely avoid FS, but should have TIC performed intra-operatively. Patients with a MSKCC value >22.5% should have TIC and FS to determine the size of metastases, whether or not to proceed with axillary lymph node dissection, and to avoid easily missed metastases.