Pathologic Examination of the Sentinel Lymph Node: What Is the Best Method?

The diagnostic accuracy of intraoperative frozen section biopsy for diagnosis of sentinel lymph node metastasis in breast cancer patients: a meta-analysis

Sentinel lymph node (SLN) sampling is important for evaluating the nodal stage of breast cancer when the axillary nodes are clinically free of metastasis. The intraoperative frozen section (IFS) of SLN is used for lymph node assessment. This meta-analysis aims to provide evidence about the diagnostic accuracy and the applicability of IFS of SLN in breast cancer patients. Data were collected by searching PubMed, Cochrane, Scopus, and Web of Science electronic databases for trials matching our eligibility criteria. The statistical analysis included the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and pooled studies' diagnostic odds ratio outcomes. The analyses were conducted using the Open Meta-analyst software. This meta-analysis pooled the results of 110 studies. The overall sensitivity of IFS for SLN metastasis was 74.7%; 95% CI [72.0, 77.2], P < 0.001. It was 31.4% 95% CI [25.2, 38.3], P < 0.001 for the micro-metastasis, and 90.2%; 95% CI [86.5, 93.0], P < 0.001 for the macro-metastasis. The overall specificity was 99.4%; 95% CI [99.2, 99.6], P < 0.001. The overall positive likelihood ratio was 121.4; 95% CI [87.9, 167.6], P < 0.001, and the overall negative likelihood ratio was 0.226; 95% CI [0.186, 0.274], P < 0.001. The overall diagnostic odds ratio of IFS for diagnosing SLN metastasis was 569.5; 95% CI [404.2, 802.4], P < 0.001. The intraoperative frozen section of SLN has good sensitivity for diagnosing breast cancer macro-metastasis. However, the sensitivity is low for micro-metastasis. The specificity is very satisfactory.

Metastases of malignant neoplasms: Historical, biological, & clinical considerations

The metastasis of neoplastic cells from their site of origin to distant anatomic locations continues to be the principal cause of death from malignant tumors, and that fact has been recognized by physicians for over a century. After the work done by Halsted in the treatment of breast cancer in the 1880s, accepted surgical canon held that metastasis occurred in a linear fashion, with centrifugal "growth in continuity" from the primary neoplasm that first involved regional lymph nodes. Those structures were considered to then be the sources of more distant, visceral metastases. With that premise in mind, radical and "ultra-radical" surgical procedures were devised to remove as many lymph nodes as possible in the treatment of carcinomas and melanomas. However, such interventions were ineffective in altering tumor-related mortality. This review considers the details of the historical material just mentioned. It also reviews currently-held concepts on biological mechanisms of metastasis, the "sentinel" lymph node biopsy technique, and the important topic of metastatic tumor "dormancy" as the cause of surgical treatment failure. Finally, predictive models of tumor behavior are discussed, which are based on gene signatures. These will likely be the key to identifying malignant lesions of low surgical stage that ultimately prove fatal through later manifestation of metastasis.

Imprint cytology versus frozen section analysis for intraoperative assessment of sentinel lymph node in breast cancer

Introduction

Sentinel lymph node (SLN) biopsy is the gold standard for surgical staging of the axilla in breast cancer (BC). Frozen section (FS) remains the most popular means of intraoperative SLN diagnosis. Imprint cytology (IC) has also been suggested as a less expensive and equally accurate alternative to FS. The aim of our study was to perform a direct comparison between IC and FS on the same SLNs of BC cases operated in a single center by the same surgical team.

Materials and methods

Into this prospective study we enrolled 60 consecutive patients with histologically proven T1–T3 BC and clinically negative axilla. Sentinel nodes were detected using a standard protocol. The SLN(s) was always assessed by IC as well as FS analysis and immunohistochemistry. Nevertheless, all intraoperative decisions were based on FS analysis.

Results

During the study period 60 patients with invasive BC were registered, with 80 SLNs harvested. Mean number of SLN(s) identified for each patient was 1.33. The sensitivity and specificity were 90% and 100%, respectively, for IC, and 80% and 100% for FS. Relevant positive/negative predictive values were 100%/98% for IC and 100%/96.15%, respectively, for FS. Overall accuracy was 98% for IC and 97% for FS. Therefore, statistically significant difference between the two methods in the detection of positive nodes was not elucidated (p=1.000).

Conclusions

IC appeared to be marginally more sensitive than FS in detecting SLN metastatic activity. Overall accuracy was 98.75%. With regard to the primary lesion characteristics, we conclude that initial lesion size and lymphovascular invasion play a pivotal role in metastatic involvement of the SLN with the dimensions of metastasis bearing no correlation with tumor size. Therefore, IC appears to be a sensitive and accurate method for the intraoperative assessment of SLN in BC patients, but further studies are required to confirm this interesting data.

Surgical margins in the veterinary cancer patient

In veterinary oncologic specimens, histopathology is the gold standard for determining adequacy of excision. Despite limitations of this technique, the pathologist's interpretation of margin status significantly impacts patient management, including indications for adjuvant therapy. This article aims to summarize peer-reviewed literature as it relates to histologic margin evaluation in veterinary cancer patients. The value of histologic tumour-free margins and technical factors influencing histopathologic margin outcomes are also discussed. We review alternative strategies for determining excisional status, and discuss how an evolving understanding of tumour biology might inform clinical and research perspectives on surgical margins. In doing so, we aim to provide context and a stimulus for future investigations into this important yet incompletely understood topic.

Practical intraoperative pathologic evaluation of sentinel lymph nodes during sentinel node navigation surgery in gastric cancer patients - Proposal of the pathologic protocol for the upcoming SENORITA trial

Over the last decade, as the number of patients with early gastric cancer increased and the subsequent survival rate improved, there has been a consistent effort to verify the applicability of the sentinel node concept in gastric cancer in a bid to improve postoperative quality of life in these patients. During sentinel node navigation surgery in gastric cancer patients, intraoperative pathologic examination of the retrieved sentinel nodes plays a critical role in determining the extent of surgery, but the optimal method is still under debate. Currently, a multicenter, phase III clinical trial is underway to compare laparoscopic sentinel basin dissection with stomach preserving surgery and standard laparoscopic gastrectomy in terms of oncologic outcomes in patients with clinical stage T1N0 gastric cancer. Herein, the currently available intraoperative pathologic techniques are reviewed and their clinical significance and applicability are appraised based on the published literature. The proper pathologic examination of the sentinel lymph nodes in an upcoming clinical trial (SENORITA trial) is also proposed here based on this review.

Results of Sentinel Lymph Node Biopsy in Patients with Breast Cancer in 10-Year Own Material of the 4th Military Teaching Hospital with Polyclinic in Wrocław

At present, sentinel lymph node biopsy is a standard procedure to assess the advancement of breast cancer and cutaneous melanoma. The aim of the study was to assess the role of the sentinel lymph node biopsy in the treatment of patients with breast cancer in our own material.

MATERIAL AND METHODS

Analyzed was medical documentation of 258 patients with initially operable breast cancer, qualified for operation with sentinel lymph node biopsy in 2004-2014 in the Department of Surgery of the 4th Military Teaching Hospital. A few hours prior to the planned surgery, radioisotope (technitium-99 sulfur colloid) was applied in the area of tumor or under the areola. 1-2 hours after administering the tracer, the lymphoscintigraphy with the labelling of the sentinel lymph node on the skin was performed.

RESULTS

On the basis of the gathered material, obtained were the following parameters: sensitivity - 100%, and specificity - 94.6%. Four cases were false negative (5.5%).

CONCLUSIONS

1. Marking the sentinel lymph node in breast cancer, based on the single visualisation method with the use of radioisotope, is a useful and effective technique. 2. The factor influencing the results of the sentinel lymph node biopsy (true positive and negative results and false negative result) was the number of the excised lymph nodes except for the sentinel lymph node. 3. Patients with estrogen receptor expression had often metastases to sentinel lymph node (145 cases - 56%). 4. The false negative rate, i.e. 5.5% in our material, is within the limits of acceptability given in the literature. 5. The sentinel lymph node biopsy performed by the experienced surgical team is a reliable diagnostic tool with a low complication rate.

Efficacy and feasibility of the immunomagnetic separation based diagnosis for detecting sentinel lymph node metastasis from breast cancer

A purpose of this study was to establish a novel molecular diagnostic model and provide new insight into the intraoperative evaluation of the sentinel lymph node (SLN) metastasis in breast cancer. A total of 124 breast cancer patients who met the criteria of sentinel lymph node biopsy (SLNB) and underwent intraoperative biopsy were consecutively enrolled in this study. After the SLNs obtained from each patient were labeled, MOC-31 monoclonal antibody-mediated immunomagnetic separation (IMS) and flow cytometry were used to determine the expressions of breast cancer metastasis-related markers, including Mucin 1 (MUC1), CD44v6, and HER2. Alternatively, conventional intraoperative hematoxylin and eosin (HE) staining and cytokeratin immunohistochemistry (CK-IHC) were performed to detect potential SLN metastasis. The sensitivity, specificity, and false-negative rate of the three intraoperative diagnostic methods were compared and analyzed. A total of 55 positive-SLNs were found in 38 breast cancer patients using IMS, yielding a sensitivity of 86.4% (38/44), specificity of 94.7% (36/38), accuracy of 93.5% (116/124), false-positive rate of 2.5% (2/80), false-negative rate of 13.6% (6/44), positive predictive value of 95.5% (42/44), and negative predictive value of 93.0% (80/86). Patients with high expressions of CD44v6, MUC1, and HER2 in SLNs tended to have higher number of positive lymph nodes, among which the MUC1 and HER2 showed significant differences (P<0.05). Therefore, compared with conventional HE staining and CK-IHC, IMS technology has remarkably higher sensitivity and specificity and relative lower false-negative rate, thus making it an effective and feasible intraoperative detection method of SLN for breast cancer diagnosis to some extent.

Potential applications of quantum dots in mapping sentinel lymph node and detection of micrometastases in breast carcinoma

Breast cancer cure aims at complete elimination of malignant cells and essentially requires detection and treatment of any micrometastases. Here, we present a review of the current methods in use and the potential role of the quantum dots (QDs) in detection and visualization of sentinel lymph node and micrometastases in breast cancer patients. The traditional histopathological, immunohistochemical, and reverse transcriptase polymerase chain reaction procedures being used for micrometastases detection had serious drawbacks of high false negativity, specificity variations and false positivity of the results. Photon emission fluorescence multiplexing characteristics of the quantum dots make them potentially ideal probes for studying the dynamics of cellular processes over time such as continuous tracking of cell migration, differentiation, and metastases. In breast cancer, QDs based molecular and genomic detections had an unparallel high sensitivity and specificity.

Implementation of step sectioning in the examination of sentinel lymph nodes to improve the detection of micrometastases in breast cancer patients

The object of this study was to examine whether a new protocol for examination of sentinel lymph nodes (SLNs) would lead to the detection of more metastases. Sections of 1 mm would identify most SLN macrometastases, and step sections at intervals of 200-250 μm would identify most micrometastases. A total of 111 breast cancer patients who underwent the SLN procedure at St. Olavs University Hospital in Trondheim, Norway in 2008 were included in the study group. Their SLNs were processed according to a new standardized protocol with sections of 2-3 mm being step sectioned at intervals of 200-250 μm. A total of 109 breast cancer patients undergoing the SLN procedure in 2007 were used as a reference group. Metastases were found in 29% of the cases, compared with 26% in the reference group. Step sectioning of SLNs revealed metastases in five cases initially found to be negative. The metastases of the study group were smaller, with a median value of 1.25 mm compared with 4.25 mm in the reference group. Step sectioning led to the detection of metastases in SLNs initially found to be negative. The median size of the metastases was considerably smaller in the study group than in the reference group.

Sentinel lymph node micrometastasis in human breast cancer: an update

INTRODUCTION

The advent of sentinel lymph node biopsy (SLNB) and advances in histopathological and molecular analysis techniques have been associated with an increase in micrometastasis (MM) detection rate. However, the clinical significance of sentinel lymph node micrometastasis (SLN MM) continues to be a subject of much debate. In this article we review the literature concerning SLN MM, with particular emphasis on the prognostic significance of SLN MM. The controversies regarding histopathological assessment, clinical relevance and management implications are also discussed.

METHODS

Literature review facilitated by Medline and PubMed databases. Cross referencing of the obtained articles was used to identify other relevant studies.

RESULTS

Published studies have reported divergent and rather conflicting results regarding the clinical significance and implications of axillary lymph node (ALN) MM in general and SLN MM in particular. Some earlier studies demonstrated no associations, however most recent studies have found SLN MM to be an indicator of poorer prognosis and to be associated with non-SLN involvement. The use of adjuvant chemotherapy and/or hormonal manipulation therapy is associated with an improved survival in patients with SLN MM. Complete ALND may be safely omitted provided that adjuvant systemic therapy recommendations are equal to patients with node-positive disease. However, optimal management of SLN MM is yet to conclude. Furthermore, the identification of MM remains largely dependent on the analytical technique employed and the use of immunohistochemistry (IHC) increases the detection rate of SLN MM. Discrepancies in the histopathological interpretation of TNM classification of SLN tumour burden do exist. Published studies were non-randomized and have significant limitations including a small sample size, limited follow-up period, and lack of standardization and reproducibility of pathological examination of the SLN.

CONCLUSION

Patients with SLN MM have a poorer prognosis than those who are SLN negative. Therapeutic recommendations regarding patients with SLN MM should be taken in the context of multidisciplinary team setting and in selected cases of SLN MM, complete ALND may be safely omitted. A better reproducibility of pathological interpretation of the TNM classification is required so that future therapeutic guidelines can be applied without confusion.

Clinical significance of sentinel lymph node isolated tumour cells in breast cancer

The advent of sentinel lymph node biopsy (SLNB) and improvements in histopathological and molecular analysis have increased the rate at which isolated tumour cells (ITC) are identified. However, their biological and clinical significance has been the subject of much debate. In this article we review the literature concerning SLNB with particular reference to ITC. The controversies regarding histopathological assessment, clinical relevance and management implications are explored. The literature review was facilitated by Medline, PubMed, Embase and Cochrane databases. Published studies have reported divergent results regarding the biological significance and clinical implications of ITC in general and SLN ITC in particular. Some studies demonstrate no associations, whilst others have found these to be indicators of poor prognosis, associated with non-SLN involvement, in addition to local recurrence and distant disease. Absolute consensus regarding the optimal analytical technique for SLN has yet to be reached, particularly concerning immunohistochemical (IHC) techniques targeting cytokeratins and contemporary molecular analysis. The clinical relevance of ITC within the SLN should be primarily determined by the magnitude of their impact on patient management and outcome measures. The modest up-staging within current classification systems is justified and reflects the marginally poorer prognosis for women with SLN ITC. Management need not be altered where further axillary treatment with surgical clearance or radiotherapy and systemic adjuvant treatment are already indicated. However, in the absence of level-1 guidance, each case requires discussion with regard to other tumour and patient related factors in the context of the multidisciplinary team. The identification of ITC remains highly dependent on the analytical technique employed and there exists potential for stage migration and impact on management decisions. Evidence supporting the routine analysis of deeper tissue sections by IHC is lacking and molecular technologies should be restricted to research purposes at present.

New FIGO staging system of vulvar cancer indeed provides a better reflection of prognosis

OBJECTIVE

To find out whether the new FIGO staging system (introduced 2009) indeed leads to a more specific prediction of the survival for patients with vulvar SCC.

METHODS

A retrospective study of 269 patients with vulvar SCC from 1988 to 2009. All patients were staged according the old and revised FIGO staging system by histopathological data. Overall survival (OS) and disease specific survival (DSS) were calculated.

RESULTS

Of all 269 patients, a total number of 113 patients (42.4%) was restaged according to the new FIGO staging, mainly downstaged. In patients with negative nodes, tumor size was not predictive for OS (p = 0.475) and DSS (p = 0.915). Patients of old FIGO stage III and negative node status showed no difference in survival with the group mentioned above (OS p = 0.105 and DSS p = 0.743, respectively). An increasing number of positive lymph nodes (range 1-9) led to a decrease in survival in OS and DSS (p = 0.022 and p = 0.004 respectively). When corrected for the number of positive nodes, there was no difference in survival between patients with unilateral or bilateral lymph nodes. In patients with positive nodes, extranodal growth showed a significant worse survival compared to patients without extranodal growth (OS p < 0.001 and DSS p = 0.004).

CONCLUSION

The new FIGO staging system provides indeed a better reflection of prognosis for patients with vulvar SCC. An accurate description of clinical and histopathological data combined with information about which FIGO classification has been used is necessary to interpret the literature correctly and to keep the possibility to compare data of different studies.

Intraoperative assessment of sentinel node using imprint cytology

BACKGROUND

Sentinel lymph node (SLN) biopsy has replaced axillary sampling as the axillary staging procedure of choice in patients with breast cancer. Accurate intraoperative evaluation of the SLN would allow axillary lymph node clearance to be performed during the initial operation when the SLN is positive for metastatic disease. The aim of the present study was to assess the accuracy of intraoperative imprint cytology (IC) of the SLN in two different institutions in the United Kingdom.

METHODS

All breast cancer patients who underwent a SLN biopsy using a standard protocol in two hospital breast units were included. The SLN was sent fresh to the pathology laboratory, where it was immediately processed and examined by a cytopathologist using IC. The intraoperative IC results were compared with the final histopathological results. No therapeutic decisions were made based on the results of IC in this study.

RESULTS

A total of 166 patients were included, with 47 positive and 119 negative cases on final histology. Of the 47 patients who were positive on final histology, there were 29 positive and 18 negative cases on IC (sensitivity = 61.7%). All 119 patients who were negative on final histology were negative on IC (specificity, 100%). The negative and positive predictive value of the final histology was 86.9% and 100%, respectively. The accuracy of IC was 89.2%.

CONCLUSIONS

The results from these two breast units are comparable with findings reported in the published literature, confirming that IC can be used to assess SLN biopsy intraoperatively. No unnecessary axillary node clearance would have been carried out based on the results of IC.

Estrogen receptor immunohistochemistry for confirmation of sentinel lymph node metastasis in cases with equivocal cytokeratin positivity

Differentiation of true metastases from cytokeratin (CK)-positive nonepithelial cells by immunohistochemistry occasionally may be difficult in the evaluation of sentinel lymph nodes (SLNs) for occult breast carcinoma metastases. In this study, we evaluated estrogen receptor (ER) immunostaining superimposed on CK as a method for the confirmation of metastasis when CK immunostaining alone was equivocal. We performed sequential ER staining on previously CK-stained slides on 15 axillary SLNs from breast cancer patients: 5 SLNs with known metastatic carcinoma (positive controls), 6 known negative SLNs (negative controls), and 4 test cases (3 SLNs in which CK-positive cells were equivocal for malignancy and 1 SLN in which metastasis was obvious, but contained focal weakly CK-positive signet ring cells). The primary tumor in all cases expressed ER in >50% of cells. Only 3 of 5 positive controls showed metastatic cells with dual CK/ER staining. CK-positive reticulum cells in all negative controls were ER negative. Three test cases showed dual CK/ER staining in the equivocal cells. The case with signet ring cells showed strong ER staining in the nonsignet ring cells and weaker staining in the signet ring cells. We conclude that dual CK/ER staining can be useful in SLNs when CK staining alone is equivocal, particularly when the primary tumor is known to have high expression of ER. Although dual ER/CK positivity helps to confirm metastasis, negative ER staining does not exclude metastatic disease.

Identification and biologic significance of micrometastases in axillary lymph nodes in patients with invasive breast cancer

CONTEXT

The presence or absence of metastases in axillary lymph nodes is one of the most important prognostic factors for patients with breast cancer. During the past decade sentinel lymph node (SLN) biopsy has been increasingly adopted as a minimally invasive staging alternative to complete axillary node dissection.

OBJECTIVE

Sentinel lymph nodes are more likely to contain metastases than non-SLNs. In routine clinical practice SLNs are assessed by diverse methodologies including multiple sectioning, immunohistochemical staining, and molecular diagnostic tests. Despite the lack of standard histopathologic protocols during the years detailed evaluation of SLNs has resulted in an increased detection of small (micro) metastases.

DATA SOURCES

Breast cancer with micrometastases constitutes a heterogenous group of tumors with variable clinical outcome regarding the risk of additional metastases in the remaining axillary lymph nodes and to patients' survival.

CONCLUSION

The clinical significance of micrometastases has been subject to great controversy in patients with breast cancer. In this review we highlight controversies regarding micrometastases especially in relation to SLNs.

Testing the Feasibility of Intra-Operative Sentinel Lymph Node Touch Imprint Cytology

INTRODUCTION

Sentinel lymph node biopsy is emerging as the new standard for axillary staging in breast cancer. Intra-operative assessment of the sentinel lymph nodes allows immediate completion of axillary dissection during the same anaesthetic. This project was a quality assurance practice to establish feasibility, time-to-report, as well as accuracy of performing intra-operative assessment of sentinel lymph nodes using touch imprint cytology in our centre.

PATIENTS AND METHODS

This prospective audit included 146 sentinel lymph nodes from 74 consecutive patients with invasive breast cancer. All patients underwent axillary sentinel lymph node biopsy using combined blue dye and radiocolloid technique. Results of intra-operative touch imprint cytology using haematoxylin and eosin staining were compared with the definitive histopathology results.

RESULTS

Mean time to report touch imprint cytology was 25.7 ± 6.4 min (range, 15–40 min). Histopathology demonstrated metastasis in 25 sentinel nodes from 17 (23%) patients. Intra-operative touch imprint cytology detected 15 nodes in 11 patients, giving a sensitivity of 60% (nodes) and 66.7% (patients) and specificity of 99.2% (nodes) and 98.2% (patients) based on the number of nodes and patients involved, respectively. Touch imprint cytology failed to show metastatic involvement in 10 nodes from 6 patients; of these, five nodes had micrometastasis (< 2 mm) and the other five had macrometastasis. One touch imprint cytology positive node contained isolated tumour cells only. Using intra-operative touch imprint cytology made a change in treatment of 11(14.9%) patients, and spared second axillary procedure in 7 (9.4%) patients.

CONCLUSIONS

Intra-operative sentinel lymph node assessment using touch imprint cytology is feasible within a busy NHS practice. We now offer touch imprint cytology to patients following appropriate counselling.

Testing the feasibility of intra-operative sentinel lymph node touch imprint cytology

INTRODUCTION

Sentinel lymph node biopsy is emerging as the new standard for axillary staging in breast cancer. Intra-operative assessment of the sentinel lymph nodes allows immediate completion of axillary dissection during the same anaesthetic. This project was a quality assurance practice to establish feasibility, time-to-report, as well as accuracy of performing intra-operative assessment of sentinel lymph nodes using touch imprint cytology in our centre.

PATIENTS AND METHODS

This prospective audit included 146 sentinel lymph nodes from 74 consecutive patients with invasive breast cancer. All patients underwent axillary sentinel lymph node biopsy using combined blue dye and radiocolloid technique. Results of intra-operative touch imprint cytology using haematoxylin and eosin staining were compared with the definitive histopathology results.

RESULTS

Mean time to report touch imprint cytology was 25.7 +/- 6.4 min (range, 15-40 min). Histopathology demonstrated metastasis in 25 sentinel nodes from 17 (23%) patients. Intra-operative touch imprint cytology detected 15 nodes in 11 patients, giving a sensitivity of 60% (nodes) and 66.7% (patients) and specificity of 99.2% (nodes) and 98.2% (patients) based on the number of nodes and patients involved, respectively. Touch imprint cytology failed to show metastatic involvement in 10 nodes from 6 patients; of these, five nodes had micrometastasis (< 2 mm) and the other five had macrometastasis. One touch imprint cytology positive node contained isolated tumour cells only. Using intra-operative touch imprint cytology made a change in treatment of 11(14.9%) patients, and spared second axillary procedure in 7 (9.4%) patients.

CONCLUSIONS

Intra-operative sentinel lymph node assessment using touch imprint cytology is feasible within a busy NHS practice. We now offer touch imprint cytology to patients following appropriate counselling.

Immunohistochemistry on frozen section of sentinel lymph nodes in breast cancer with improved morphology and blocking of endogenous peroxidase

Sentinel lymph node biopsy in the management of patients with breast cancer is the clinical practice. Peroperative examination means that more patients can be treated in a 1-step procedure. The addition of immunohistochemistry to frozen section slides improves the detection rate of especially micrometastasis. We present a novel method for immunohistochemical staining on a frozen section material that gives better morphology and blocks endogenous peroxidase sufficiently.

Meta-analysis of sentinel node biopsy in ductal carcinoma in situ of the breast

BACKGROUND

The need for sentinel lymph node (SLN) biopsy in patients with a preoperative diagnosis of ductal carcinoma in situ (DCIS) is debated. Advocates recommend such biopsy based on a high incidence of SLN involvement in some series. Opponents discourage SLN biopsy based on a perceived low incidence of nodal involvement in this setting. These contradictory arguments are generally based on small studies. The present study is a meta-analysis of the reported data on the incidence of SLN metastasis in patients with DCIS.

METHODS

A search of electronic databases identified studies reporting the frequency of SLN metastases in DCIS. The random-effects method was used to combine data.

RESULTS

Twenty-two published series were included in the meta-analysis. The estimate for the incidence of SLN metastases in patients with a preoperative diagnosis of DCIS was 7.4 (95 per cent confidence interval (c.i.) 6.2 to 8.9) per cent compared with 3.7 (95 per cent c.i. 2.8 to 4.8) per cent in patients with a definitive (postoperative) diagnosis of DCIS alone. This was a significant difference with an odds ratio of 2.11 (95 per cent c.i. 1.15 to 2.93).

CONCLUSION

Patients with a preoperative diagnosis of DCIS should be considered for SLN biopsy.

The clinical significance of sentinel lymph node micrometastasis in breast cancer

INTRODUCTION

The advent of sentinel lymph node biopsy (SLNB) and improvements in histopathological and molecular analysis have increased the rate at which micrometastases (MM) are identified. However, their significance has been the subject of much debate. In this article we review the literature concerning axillary lymph node (ALN) MM, with particular reference to SLNB. The controversies regarding histopathological assessment, clinical relevance and management implications are discussed.

METHODS

Literature review facilitated by Medline and PubMed databases.

RESULTS

Published studies have reported divergent results regarding the significance and implications of ALN MM in general and sentinel lymph node (SLN) MM in particular. Some studies demonstrate no associations, whilst others have found these to be indicators of poor prognosis, associated with non-SLN involvement, in addition to local and distant failure. Absolute consensus regarding the optimal analytical technique for SLNs has yet to be reached, particularly concerning immunohistochemical (IHC) techniques targeting cytokeratins and the utility of contemporary molecular analysis.

CONCLUSION

SLN MM are likely to represent an incremental detriment to prognosis and increased risk of non-SLN involvement, despite only modest up-staging within current classification systems. In the absence of level-1 guidance concerning the management of women with SLN MM, each case requires discussion with regard to other tumour and patient related factors in the context of the multidisciplinary team. Randomized studies are required to evaluate the prognostic significance and optimal management of each category of tumour burden within the SLN. The identification of MM remains highly dependent on the analytical technique employed and there exists potential for stage migration and impact on management decisions.

Application of immunohistochemistry to breast lesions

CONTEXT

Immunohistochemistry has an expanding role in mammary pathology that has been facilitated by a growing list of available antibodies and a better understanding of biology.

OBJECTIVE

To explore the key role of immunohistochemistry in guiding adjuvant therapy decisions and sentinel node staging in breast cancer, as well as the role of immunohistochemistry as an aid to distinguishing usual ductal hyperplasia from atypical ductal hyperplasia/low-grade carcinoma in situ; subtyping a carcinoma as ductal or lobular, basal or luminal; ruling out microinvasion in extensive intraductal carcinoma; distinguishing invasive carcinoma from mimics; and establishing that a metastatic carcinoma of unknown primary site has originated in the breast.

DATA SOURCES

Current literature is reviewed, including clinical and pathologic journals.

CONCLUSIONS

As new, targeted treatments for breast cancer are developed, pathologists can expect additional immunohistochemistry applications in the future.

Outcomes following sentinel lymph node biopsy for breast cancer

Evaluation of axillary lymph nodes for metastatic involvement is the most significant factor in gauging prognosis in breast cancer patients. Complete axillary dissection can be associated with significant morbidity. Therefore, sentinel node biopsy was developed to sample nodes and avoid dissection in patients without clinical evidence of nodal involvement. While most surgeons currently perform the procedure, the technique remains unstandardized. Sentinel node identification rates, false-negative rates and procedural complication rates are the main outcomes measured and can depend significantly on variations in technique. Future studies on sentinel lymph node biopsy will probably focus on clarifying accuracy of the procedure in different clinical settings, delineating standard technical practice guidelines and further achieving improved outcomes.

Standardizing Slide-Based Assays in Breast Cancer: Hormone Receptors, HER2, and Sentinel Lymph Nodes

Despite the rapid expansion of novel diagnostics designed to personalize breast cancer care, there remain several significant unmet needs for improving the accuracy and reliability of tests that are already in common daily clinical practice. For example, although immunohistochemistry has been the predominant method for measuring estrogen receptor and progesterone receptor status for over 15 years, this assay remains unstandardized and there is a widespread concern that inaccuracy in immunohistochemistry technique and interpretation is leading to an unacceptably high error rate in determining the true hormone receptor status. Similarly, there is considerable concern that both false-negative and false-positive result rates for testing for HER2 status are unacceptably high in current clinical practice. This commentary considers a variety of factors, including preanalytic conditions and slide-scoring procedures, and other variables that may be contributing to current testing error rates and why there is a great need for the standardization of these biomarker assay procedures to further enable the highest possible quality of care for newly diagnosed breast cancer patients.

Current status of sentinel lymph node navigation surgery in breast and gastrointestinal tract

Sentinel lymph node biopsy (SLNB) has been developed as a new diagnostic and therapeutic modality in melanoma and breast cancer surgery. The purpose of the SLNB include preventing the operative morbidity and improving the pathologic stage by focusing on fewer lymph nodes using immunocytochemic and molecular technology has almost achieved in breast cancer surgery. The prognostic meaning of immunocytochemically detected micrometastases is also evaluating in the SLN and bone marrow aspirates of women with early-stage breast cancer. SLNB using available techniques have suggested that the lymphatic drainage of the gastrointestinal tract is much more complicated than other sites, skip metastasis being rather frequent because of an aberrant lymphatic drainage outside of the basin exist. At the moment, the available data does not justify reduced extent of lymphadenectomy, but provides strong evidence for an improvement in tumor staging on the basis of SLNB. Two large scale prospective multi-center trials concerning feasibility of gamma-probe and dye detection for gastric cancer are ongoing in Japan. Recent studies have shown favorable results for identification of SLN in esophageal cancer. CT lymphography with endoscopic mucosal injection of iopamidol was applicable for SLN navigation of superficial esophageal cancer. The aim of surgical treatment is complete resection of the tumor-infiltrated organ including the regional lymph nodes. Accurate detection of SLN can achieve a selection of a more sophisticated tailor made approach. The patient can make a individualized choice from a broader spectrum of therapeutic options including endoscopic, laparoscopic or laparoscopy-assisted surgery, modified radical surgery, and typical radical surgery with lymph node dissection. Ultrastaging by detecting micrometastasis at the molecular level and the choice of an adequate treatment improve the postoperative quality of life and survival. However these issues require further investigation.

Contraindications of sentinel lymph node biopsy: are there any really?

BACKGROUND

One of the most exciting and talked about new surgical techniques in breast cancer surgery is the sentinel lymph node biopsy. It is an alternative procedure to standard axillary lymph node dissection, which makes possible less invasive surgery and side effects for patients with early breast cancer that wouldn't benefit further from axillary lymph node clearance. Sentinel lymph node biopsy helps to accurately evaluate the status of the axilla and the extent of disease, but also determines appropriate adjuvant treatment and long-term follow-up. However, like all surgical procedures, the sentinel lymph node biopsy is not appropriate for each and every patient.

METHODS

In this article we review the absolute and relative contraindications of the procedure in respect to clinically positive axilla, neoadjuvant therapy, tumor size, multicentric and multifocal disease, in situ carcinoma, pregnancy, age, body-mass index, allergies to dye and/or radio colloid and prior breast and/or axillary surgery.

RESULTS

Certain conditions involving host factors and tumor biologic characteristics may have a negative impact on the success rate and accuracy of the procedure. The overall fraction of patients unsuitable or with multiple risk factors that may compromise the success of the sentinel lymph node biopsy, is very small. Nevertheless, these patients need to be successfully identified, appropriately advised and cautioned, and so do the surgeons that perform the procedure.

CONCLUSION

When performed by an experienced multi-disciplinary team, the SLNB is a highly effective and accurate alternative to standard level I and II axillary clearance in the vast majority of patients with early breast cancer.