The real-time intra-operative evaluation of sentinel lymph nodes in breast cancer patients using One Step Nucleic Acid Amplification (OSNA) and implications for clinical decision-making

Diagnostic value of one-step nucleic acid amplification for sentinel lymph node metastasis in cytokeratin 19-positive tumors: evidence from bioinformatics and meta-analysis

Background

The status of the sentinel lymph nodes (SLNs) was an important prognostic factor in varies cancers. A one-step nucleic acid amplification (OSNA) assay, a molecular-based whole-node analysis method based on CK19 mRNA copy number, was developed to diagnose lymph node metastases. We aimed to evaluate the value of OSNA for the diagnosis of sentinel lymph node metastasis in CK19 positive cancers. CK19 mRNA and protein expression for pan-caner analysis were obtained from TCGA and the Human protein atlas database.

Methods

Two researchers independently searched the PubMed, Cochrane Library and Web of Science databases for qualified articles published before December 1, 2023. A meta-analysis was performed using MetaDisc and STATA. Risk bias and quality assessments of the included studies were evaluated, and a subgroup analysis was performed. Ten cancer types were found to be CK19 positively expressed and 7 of 10 had been reported to use OSNA for SLN detection.

Results

After literature review, there were 61 articles included in the meta-analysis, which consisted of 7115 patients with 18007 sentinel lymph nodes. The pooled sensitivity and specificity of OSNA were 0.87 and 0.95 in overall patients. Moreover, we found the background CK19 expression in normal tissue affected the diagnostic accuracy of OSNA. In breast cancer, we performed subgroup analysis. OSNA exhibited to be a stable method across different population groups and various medical centers. In addition, when 250 copies/μl was chosen as the cutoff point of CK19 mRNA, there were a relatively higher sensitivity and AUC in detecting SLN micro-metastasis than 5000 copies/μl.

Discussion

OSNA can predict the occurrence of SLN metastasis accurately in CK19 positive cancers, especially in breast cancer, colorectal cancer, lung cancer, gastric cancer and endometrial cancer. Our study warrants future studies investigating the clinical application of OSNA in pancreatic, ovarian and bladder cancers.

Axillary Treatment Management in Breast Cancer during COVID-19 Pandemic (Association between ACOSOG Z0011 Criteria and OSNA Test)

The outbreak of the SARS-COVID-2 pandemic (COVID-19) had a significant effect on the organisation of healthcare systems. Surgical units saw a significant reduction in the volume of surgical procedures performed, with lengthening waiting lists as a consequence. We assessed the surgical activity in relation to breast cancer that took place at the University Hospital of Cagliari, Italy, from February 2018 to March 2022. Two phases were identified based on the epidemiological circumstances: Phase 1-February 2018 to February 2020; Phase 2-March 2020 to March 2022. The surgery performed in the two phases was then compared. All the patients in our sample underwent a breast surgical procedure involving a lymph node biopsy using OSNA associated with the ACOSOG Z0011 criteria. In the study period overall at our facility, there were 4214 procedures, 417 of which involved breast surgery. In Phase 2, 91 procedures were performed using the OSNA method and ACOSOG Z0011 criteria, enabling the intraoperative staging of axillary nodes. Axillary treatment in breast cancer using this approach resulted in a significant reduction in the number of reoperations for the radicalisation of metastatic sentinel lymph nodes.

Septin 9 methylation analysis of lymph node micrometastases for predicting relapse of colorectal cancer

BACKGROUND

Molecular markers for the detection of lymph node micrometastases of malignant tumors have been extensively investigated. However, epigenetic signatures have rarely been reported for identification of metastatic lymph nodes and disease relapse. Septin 9 is the most frequently reported hypermethylated gene in colorectal cancer (CRC). This study aimed to assess the clinical relevance of Septin 9 methylation in regional lymph nodes in recurrence/metastases of CRC.

METHODS

We analyzed Septin 9 methylation of DNA from resected lymph nodes in 75 CRC patients with or without tumor recurrence using quantitative methylation-sensitive PCR (qMS-PCR).

RESULTS

Of the 30 histologically negative lymph node CRC patients without recurrence (group 1), methylated Septin 9 was detected in 3 (10 %) cases. The positivity rate of methylated Septin 9 in group 2 containing 30 histologically node-negative CRC patients with recurrence was 30 % (9/30). For group 3, lymphatic invasion as well as tumor recurrence, 11 (73 %) out of 15 subjects had Septin 9 methylation-positive lymph nodes. Moreover, patients in group 3 had a higher level of methylated Septin 9 compared to subjects in group 1 and group 2 (p < 0.05). In addition, CRC patients with Septin 9 methylation in lymph nodes had significantly reduced survival (Log-rank P < 0.0001).

CONCLUSION

Our data support the predictive role of Septin 9 methylation analysis of lymph node micrometastases for tumor relapse after surgery.

One-step nucleic acid amplification for intraoperative diagnosis of lymph node metastasis in lung cancer patients: a single-center prospective study

One-step nucleic acid amplification (OSNA) is a rapid intraoperative molecular detection technique for sentinel node assessment via the quantitative measurement of target cytokeratin 19 (CK19) mRNA to determine the presence of metastasis. It has been validated in breast cancer but its application in lung cancer has not been adequately investigated. 214 LNs from 105 patients with 100 primary lung cancers, 2 occult primary lung tumors, and 3 metastatic lung tumors, who underwent surgical lung resection with LN dissection between February 2018 and January 2020, were assessed. Resected LNs were divided into two parts: one was snap-frozen for OSNA and the other underwent rapidly frozen histological examination. Intraoperatively collected LNs were evaluated by OSNA using loop-mediated isothermal amplification and compared with intraoperative pathological diagnosis as a control. Among 214 LNs, 14 were detected as positive by OSNA, and 11 were positive by both OSNA and intraoperative pathological diagnosis. The sensitivity and specificity of OSNA was 84.6% and 98.5%, respectively. The results of 5 of 214 LNs were discordant, and the remainder all matched (11 positive and 198 negative) with a concordance rate of 97.7%. Although the analysis of public mRNA expression data from cBioPortal showed that CK19 expression varies greatly depending on the cancer type and histological subtype, the results of the five cases, except for primary lung cancer, were consistent. OSNA provides sufficient diagnostic accuracy and speed and can be applied to the intraoperative diagnosis of LN metastasis for non-small cell lung cancer.

Is it Possible to Predict Non Sentinel Node Positivity on the Basis of mRNA Copy Numbers of CK19 Receptor in Breast Cancer?

AIMS

To determine if there is any correlation between the number of positive non-sentinel lymph nodes (NSLN) and the mRNA copy numbers of cytokeratin 19 receptor on one step nucleic acid amplification (OSNA) in the sentinel lymph node (SLN).

METHODS

An 8-year retrospective study of consecutive patients who had primary surgery and sentinel node biopsy for breast cancer from January 2011 to December 2018 was carried out. All these patients had intra-operative analysis of sentinel lymph nodes by OSNA. Patients who had neoadjuvant chemotherapy or neoadjuvant endocrine therapy were excluded.

RESULTS

There were 1159 patients with an age range of 24 to 90 years and a mean age of 63 years in this study. A total of 1324 SLNs were analyzed by OSNA. Macrometastasis was found in 120 patients and they underwent axillary lymph node dissection (ALND). A total of 2405 NSLNs were analyzed. Of the patients who had ALND, 51 (43%) patients had negative NSLNs and 69 (57%) had positive NSLNs. The mean mRNA copy numbers respectively for the 2 groups were 853,665 and 609,855. The difference between the means is not statistically significant (P = 0.82). Also the Receiver Operating Characteristic (ROC) Curve of the total CK-19 mRNA copy number for both groups-negative and positive NSLN were almost identical (Figure 3) indicating mRNA copy numbers cannot be used to discriminate between positive and negative non-sentinel lymph nodes.

CONCLUSION

It is clear from our study that in patients who have ALND due to macromets on OSNA, there is no correlation between the total tumor load as represented by mRNA copy numbers and the likelihood of positive non-sentinel lymph nodes. We therefore cannot rely solely on the mRNA copy numbers to decide on ALND.

Update on new imaging technologies in sentinel node detection

In most cancers, lymph node status is the most critical factor impacting the evolution of the disease and the overall survival. Identifying potential nodal metastasis allows the oncologist to adjust the stage and, consequently, the patient's treatment. For this reason, a precise evaluation of the regional nodes is mandatory. In gynecological cancers, pelvic, paraaortic, and inguinal nodes are the region most frequently interested by metastasis. In the past years, comprehensive lymphadenectomy was the standard of care for endometrial, cervical, ovarian, and vulvar cancers. However, after introducing the sentinel lymph node (SNL) biopsy in breast cancers, this technique has gained much more interest in gynecology oncology. Several studies have shown that SLN allows an evaluation of the node status without the complications related to the lymphadenectomy that impacts the patient's quality of life. In this review, we discuss the role of SNL biopsy in gynecological cancers and the technique's evolution over the years. Moreover, we debate the OSNA method for SLN analysis that is recently introduced for uterine cancer.

The evolving role of one-step nucleic acid amplification (OSNA) for the intra-operative detection of lymph node metastases: A diagnostic accuracy meta-analysis

BACKGROUND

One Step Nucleic Acid Amplification (OSNA) assay has recently emerged as a rapid molecular diagnostic tool for the detection of lymph node (LN) metastases. It is a molecular technique that analyses the entire LN tissue using a reverse-transcriptase loop-mediated isothermal amplification reaction to detect tumour specific cytoceratin 19 mRNA.

AIM

To ascertain the diagnostic accuracy of OSNA assay in detecting LN metastases amongst different types of malignancy.

DESIGN

We systematically searched MEDLINE, SCOPUS, ClinicalTrials.gov, and Cochrane Database, from inception up to August 2020. Quality assessment was performed using the Modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). We calculated pooled diagnostic indices using the random-effects model. Meta-regression and sub-group analyses were performed to address heterogeneity.

RESULTS

31 studies were included in this meta-analysis, including four different types of cancer. The risk of bias and the overall quality of included studies was moderate to high. There was no evidence of publication bias. The pooled diagnostic odds ratio (DOR) for detecting LN metastases in gynaecological, head & neck/thyroid, gastrointestinal and lung cancer were 100.38, 76.17, 275.14, and 305.84, respectively.

CONCLUSIONS

Our findings suggest that OSNA assay had a high diagnostic accuracy in detecting metastatic LNs in different types of malignancy. This evidence is constrained by the limited studies available for few tumour types and the rather high heterogeneity for few outcomes.

Prognostic Significance of Lymph Node Examination by the OSNA Method in Lung Cancer Patients-Comparison with the Standard Histopathological Procedure

The aim of the study was to compare the prognostic significance of lymph node status of patients with lung cancer analyzed by three different methods: hematoxylin and eosin (H&E), immunohistochemistry of cytokeratin 19 (IHC CK19), and One-Step Nucleic Acid Amplification (OSNA). The clinical relevance of the results was evaluated based on relation to prognosis; the disease-free interval (DFI) and overall survival (OS) were analyzed. During radical surgical treatment, a total of 1426 lymph nodes were obtained from 100 patients, creating 472 groups of nodes (4–5 groups per patient) and examined by H&E, IHC CK19 and OSNA. The median follow-up was 44 months. Concordant results on the lymph node status of the H&E, IHC CK19 and OSNA examinations were reported in 78% of patients. We recorded shorter OS in patients with positive results provided by both OSNA and H&E. The study demonstrated a higher percentage of detected micrometastases in lymph nodes by the OSNA method. However, the higher sensitivity of the OSNA, with the cut-off value 250 copies of mRNA of CK19/µL, resulted in a lower association of OSNA positivity with progress of the disease compared to H&E. Increasing the cut-off to 615 copies resulted in an increase in concordance between the OSNA and H&E, which means that the higher cut-off is more relevant in the case of lung tumors.

OPTimizing Irradiation through Molecular Assessment of Lymph node (OPTIMAL): a randomized open label trial

BACKGROUND

Conservative surgery followed by breast and nodal irradiation is the standard loco-regional early breast cancer (BC) treatment for patients with four or more involved lymph nodes. However, the treatment strategy when fewer nodes are involved remains unclear, especially when lymphadenectomy has not been performed. Sensitive nodal status assessment molecular techniques as the One-Step Nucleic Acid Amplification (OSNA) assay can contribute to the definition and standardization of the treatment strategy. Therefore, the OPTIMAL study aims to demonstrate the feasibility of incidental irradiation of axillary nodes in patients with early-stage BC and limited involvement of the SLN.

METHODS

BC patients who underwent conservative surgery and whose SLN total tumour load assessed with OSNA ranged between 250-15,000 copies/µL will be eligible. Patients will be randomized to receive irradiation on the breast, tumour bed, axillary and supraclavicular lymph node areas (intentional arm) or only on the breast and tumour bed (incidental arm). All areas, including the internal mammary chain, will be contoured. The mean, median, D5% and D95% doses received in all volumes will be calculated. The primary endpoint is the non-inferiority of the incidental irradiation of axillary nodes compared to the intentional irradiation in terms of 5-year disease free survival. Secondary endpoints comprise the comparison of acute and chronic toxicity and loco-regional and distant disease recurrence rates.

DISCUSSION

Standardizing the treatment and diagnosis of BC patients with few nodes affected is crucial due to the lack of consensus. Hence, the quantitative score for the metastatic burden of SLN provided by OSNA can contribute by improving the discrimination of which BC patients with limited nodal involvement can benefit from incidental radiation as an adjuvant treatment strategy.

TRIAL REGISTRATION

ClinicalTrial.gov, NCT02335957; https://clinicaltrials.gov/ct2/show/NCT02335957.

Role of one-step nucleic acid amplification (OSNA) to detect sentinel lymph node low-volume metastasis in early-stage cervical cancer

INTRODUCTION

Growing evidence in the literature supports the accuracy of sentinel lymph node (SLN) biopsy in early-stage cervical cancer. One-step nucleic acid amplification (OSNA) is a rapid assay able to detect cytokeratin 19-mRNA in SLNs, and it can be used for intra-operative detection of low-volume metastases. The aim of this study was to evaluate the rate of low-volume metastasis in SLNs detected by OSNA in patients with early-stage cervical cancer. Secondary aims were to define the sensitivity and the negative predictive value of SLN biopsy assessed with OSNA.

METHODS

After IRB approval, consecutive patients who underwent surgery for International Federation of Gynecology and Obstetrics stage IA1 with lymph-vascular space involvement to IB1 between November 2017 and July 2019 and had SLN biopsy and pelvic lymphadenectomy were included. SLNs were detected with indocyanine-green cervical injection and sent intra-operatively for OSNA.

RESULTS

Eighteen patients underwent SLN assessment with OSNA and systematic pelvic lymphadenectomy in the study period. Four (22.2%) patients had unilateral and 14 (77.8%) had bilateral mapping. OSNA detected micro-metastasis in 6/18 (33.3%) patients. All micro-metastases were detected in patients with bilateral SLN mapping. The sensitivity and negative predictive value of SLN in detecting lymph node metastasis with OSNA calculated per pelvic sidewall were 85.7% and 96.1%, respectively. The false negative rate in mapped sidewalls was 14.3%.

DISCUSSION

This is the first series entirely processing SLNs for OSNA in early-stage cervical cancer. OSNA is able to intra-operatively detect low-volume metastases in SLNs. Further studies are necessary to confirm the accuracy of this technique and to assess survival implications of low-volume metastases detected by OSNA.

Twenty-five years of change in the management of the axilla in breast cancer

Sentinel lymph node (SLN) biopsy is now used worldwide. It has led to many changes in how we manage the axilla in patients with breast cancer. This review covers four areas of management of the axilla in breast cancer: assessing the clinically node-negative axilla, managing the clinically negative axilla found to be involved at SLN biopsy, management of the clinically positive axilla in the context of neo-adjuvant chemotherapy, and treatment of the diseased axilla when radical therapy is required. We suggest that the evidence supports an optimum number of 3 nodes to be removed for accurate SLN biopsy. Breast cancer departments that have not adopted Z0011 patient management cannot continue to avoid change. The evidence is clear: Not all patients with limited axillary nodal disease on sentinel node biopsy need axillary lymph node dissection. For patients who do need axillary treatment, axillary radiotherapy continues to be under-used. Patients undergoing neo-adjuvant chemotherapy can be safely assessed by post-therapy SLN biopsy, with retrieval of any previously biopsied involved nodes by targeted axillary dissection. There is much to support the trend to doing less in the axilla. We are obliged to act based on the available robust clinical trial data in a way that limits morbidity while at the same time does not increase the risk of disease recurrence.

Can Complete Axillary Node Dissection Be Safely Omitted in Patients with Early Breast Cancer When the Sentinel Node Biopsy Is Positive for Malignancy? An Update for Clinical Practice

The sentinel lymph node biopsy (SLNB) has become the new standard-of-care for patients with clinically node-negative invasive breast cancer. The focused examination of fewer lymph nodes in addition to improvements in histopathological and molecular analysis have increased the rate at which micrometastases and isolated tumor cells are identified. We reviewed the literature and summarized the evidence regarding the need for complete axillary lymph node dissection (ALND) following the finding of a positive sentinel node biopsy through the identification of the most important outcomes and evaluation of quality of evidence. The article focuses on the safe omission of complete ALND when the axillary lymph nodes contain macrometastases and provides an overview of the topic primarily based on level 1 evidence derived from randomized clinical trials with a critical appraisal of the ACOSOG Z0011 trial.

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 (OSNA): A fast molecular test based on CK19 mRNA concentration for assessment of lymph-nodes metastases in early stage endometrial cancer

INTRODUCTION

The aim of the current study is to evaluate the detection rate of micro- and macro-metastases of the One-Step Nucleic Acid Amplification (OSNA) compared to frozen section examination and subsequent ultra-staging examination in early stage endometrial cancer (EC).

MATERIAL AND METHODS

From March 2016 to June 2016, data of 40 consecutive FIGO stage I EC patients were prospectively collected in an electronic database. The sentinel lymph node mapping was performed in all patients. All mapped nodes were removed and processed. Sentinel lymph nodes were sectioned and alternate sections were respectively examined by OSNA and by frozen section analysis. After frozen section, the residual tissue from each block was processed with step-level sections (each step at 200 micron) including H&E and IHC slides.

RESULTS

Sentinel lymph nodes mapping was successful in 29 patients (72.5%). In the remaining 11 patients (27.5%), a systematic pelvic lymphadenectomy was performed. OSNA assay sensitivity and specificity were 87.5% and 100% respectively. Positive and negative predictive values were 100% and 99% respectively, with a diagnostic accuracy of 99%. As far as frozen section examination and subsequent ultra-staging analysis was concerned, we reported sensitivity and specificity of 50% and 94.4% respectively; positive and negative predictive values were 14.3% and 99%, respectively, with an accuracy of 93.6%. In one patient, despite negative OSNA and frozen section analysis of the sentinel node, a macro-metastasis in 1 non-sentinel node was found.

CONCLUSIONS

The combination of OSNA procedure with the sentinel lymph node mapping could represent an efficient intra-operative tool for the selection of early-stage EC patients to be submitted to systematic lymphadenectomy.

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.

A more sensitive detection of micrometastases of NSCLC in lymph nodes using the one-step nucleic acid amplification (OSNA) method

BACKGROUND

Detection of tumor cells in lymph nodes (LNs) removed during the treatment of pulmonary tumor by radical surgery is limited by the possibilities of standard histopathological methods. The goal of this study was to obtain more accurate pTNM status by a more sensitive detection of micrometastases in LNs.

METHODS

A total of 885 LNs, an average of 13.8 LNs per patient, were removed during 64 surgeries. LNs from the same zone were pooled together as a group, five groups of LNs were examined in each patient. A total of 320 groups of LNs were examined. One-step nucleic acid amplification (OSNA) method was compared to standard histopathological examination with haematoxylin-eosin (H&E) staining and CK19 immunohistochemistry, specifically by an ultimate analysis of all intraoperatively removed LNs.

RESULTS

Identical results for H&E and OSNA examinations were recorded in 286 groups of LNs (89.4%). In total, positive examinations were recorded in 27 groups of LNs (8.4%) using the OSNA method, which were H&E negative. In seven groups of LNs (2.2%), the H&E examination was positive, while OSNA method produced negative results.

CONCLUSIONS

The OSNA examination led to a higher pTNM stage classification in 14 (21.9%) patients. The clinical significance remains the subject of follow-up research.

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.

One-step nucleic acid amplification assay is an accurate technique for sentinel lymph node biopsy of breast cancer patients: a meta-analysis

Background:

To estimate the accuracy of one-step nucleic acid amplification (OSNA) assay as an intra-operative sentinel lymph node biopsy (SLNB) for sentinel lymph node (SLN) metastasis in breast cancer.

Methods:

PubMed, Cochrane Library and Web of Science databases were searched by two independent reviewers to retrieve literature with per-patient analysis. The deadline was up until December 2016. A meta-analysis was performed using STATA, Meta-Disc, and Revman software. A random-effects model was used and subgroup analysis was carried out to identify possible sources of heterogeneity.

Results:

According to the inclusion criteria, 2833 patients from 12 studies were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and the area under the sROC curve (AUC) for detecting SLN metastasis were 0.87 (95% CI 0.81–0.91), 0.92 (95% CI 0.86–0.95), 10.65 (95% CI 6.18–18.34), 0.14 (95% CI 0.10–0.20), 75.08 (95% CI 37.77–149.22) and 0.94 (95% CI 0.91–0.95), respectively.

Conclusions:

The present study adds the evidence that OSNA assay is an accurate molecular diagnostic tool for intra-operatively detecting SLN metastasis in breast cancer. One-step nucleic acid amplification assay might be introduced into clinical usage for replacing traditional intro-operative diagnostic methods of SLNB.

Sentinel lymph node biopsy in breast cancer: the role of micrometastasis

Intraoperative sentinel lymph node biopsy is widely used in patients with early-stage breast cancer for staging the axilla. The conventional analysis of the SLN has classically been performed by frozen section or touch imprint with a rapid H&E (hematoxylin and eosin) staining. Because of the risk of false-negative results, it has been replaced by the one-step acid amplification (OSNA) assay, a molecular diagnostic assay for the detection of cytokeratin 19 mRNA expression. Due to the controversial for the use of OSNA to evaluate the SLN because of its cost-effective and the lack of consensus to perform or avoid a lymphadenectomy when there is micrometastasis, we analyze 410 patients subjected to SLN biopsy in Hospital Puerta de Hierro, Madrid (Spain). Of the total of nodes, 223 (54.4 %) were processed throughout frozen-section examination and imprint cytology and 187 (45.6 %) throughout OSNA. The specificity of the frozen-section histological examination was of 100 %, with a sensitivity of 83.33 % (95 % CI 73.07-93.60). Of the 40 patients with definitive micrometastasis in the SLN, axillary dissection was performed in 90 % of the patients, with subsequent positive affectation in four of them (11.11 %). Based on our result and taking into account that 10 % of the lymphadenectomy performed after micrometastasis are positive, we do not believe that lymphadenectomy should be avoided after N(mi+) is detected in a SLN.

Clinical usefulness of one-step nucleic acid amplification assay in the new era of sentinel lymph node biopsy for breast cancer

SUMMARY 

According to the results of the ACOSOG Z0011 trial and IBCSG trial 23-01, rapid intraoperative examinations of the sentinel lymph nodes (SLN) are needed in only a limited number of breast cancer patients, including those with more than three sentinel nodes or who undergo mastectomy. In this new era of SLN biopsies, one-step nucleic acid amplification assay is a promising method for accurately assessing metastasis in the whole SLN, and which help to accurately select patients requiring axillary dissection and reliably evaluate the risk of recurrence. One-step nucleic acid amplification assay may therefore be an alternative to conventional pathology in detecting metastasis in the SLNs, when used for both intraoperative and postoperative examinations.

Towards optimal management of the axilla in the context of a positive sentinel node biopsy in early breast cancer

The sentinel lymph node biopsy (SLNB) was initially pioneered for staging melanoma in 1994 and it has been subsequently validated by several trials, and has become the new standard of care for patients with clinically node negative invasive breast cancer. The focussed examination of fewer lymph nodes in addition to improvements in histopathological and molecular analysis has increased the rate at which micrometastases and isolated tumour cells are identified. In this article we review the literature regarding the optimal management of the axilla when the SLNB is positive for metastatic disease based on level 1 evidence derived from randomised clinical trials.

OSNA (one-step nucleic acid amplification) sentinel lymph node intraoperative molecular analysis in breast cancer: a cost-benefit analysis

The aim of the study was to analyze the medical and economic interest of OSNA molecular technique, compared to conventional postoperative histopathologic evaluation for sentinel lymph node exploration in breast cancer patients. This retrospective cost-benefit study was conducted in the French Universitary Hospital of Saint Etienne on patients who received sentinel lymph node exploration between July 1, 2007 and December 31, 2009. Lymph nodes were analyzed by conventional postoperative histological evaluation in group 1 (82 patients) and OSNA in group 2 (86 patients). Costs were analyzed in three different ways: surgery cost, hospitalization cost and histopathologic cost. Average operating time was slightly shorter for group 1 (histology) [71.9 vs. 76.8 min for group 2 (OSNA)]. Time and operating costs were not significantly different (p = 0.293). The average cost of pathological examination was significantly higher in group 2 (35.04 euros per node in group 1 vs. 291.84 euros per node in group 2 p < 10(-3)). The average length of hospital stay was significantly longer in group 1 (5.4 days in group 1 vs. 4.2 days in group 2, p = 0.0065). The total costs were not significantly different between both groups (3,774.6 euros in group 1 vs. 3,393.9 euros in group 2 p = 0.055). The sentinel lymph node analysis with OSNA technique does not lead to higher expenses. It also avoids another surgery for 20% of patients. A prospective multicentric medico-economic study made with a larger effective would probably confirm these results.