Staging efficacy of breast cancer with sentinel lymphadenectomy

Can We Skip Intraoperative Evaluation of Sentinel Lymph Nodes? Nomogram Predicting Involvement of Three or More Axillary Lymph Nodes before Breast Cancer Surgery

Purpose

The American College of Surgeons Oncology Group Z0011 trial reported that complete dissection of axillary lymph nodes (ALNs) may not be warranted in women with clinical T1-T2 tumors and one or two involved ALNs who were undergoing lumpectomy plus radiation followed by systemic therapy. The present study was conducted to identify preoperative imaging predictors of ≥ 3 ALNs.

Materials and Methods

The training set consisted of 1,917 patients with clinical T1-T2 and node negative invasive breast cancer. Factors associated with ≥ 3 involved ALNs were evaluated by logistic regression analysis. The validation set consisted of 378 independent patients. The nomogram was applied prospectively to 512 patients who met the Z0011 criteria.

Results

Of the 1,917 patients, 204 (10.6%) had ≥ 3 positive nodes. Multivariate analysis showed that involvement of ≥ 3 nodes was significantly associated with ultrasonographic and chest computed tomography findings of suspicious ALNs (p < 0.001 each). These two imaging criteria, plus patient age, were used to develop a nomogram calculating the probability of involvement of ≥ 3 ALNs. The areas under the receiver operating characteristic curve of the nomogram were 0.852 (95% confidence interval [CI], 0.820 to 0.883) for the training set and 0.896 (95% CI, 0.836 to 0.957) for the validation set. Prospective application of the nomogram showed that 60 of 512 patients (11.7%) had scores above the cut-off. Application of the nomogram reduced operation time and cost, with a very low re-operation rate (1.6%).

Conclusion

Patients likely to have ≥ 3 positive ALNs could be identified by preoperative imaging. The nomogram was helpful in selective intraoperative examination of sentinel lymph nodes.

Blue dye for identification of sentinel nodes in breast cancer and malignant melanoma: a systematic review and meta-analysis

The combined technique (radioisotope and blue dye) is the gold standard for sentinel lymph node biopsy (SLNB) and there is wide variation in techniques and blue dyes used. We performed a systematic review and meta-analysis to assess the need for radioisotope and the optimal blue dye for SLNB. A total of 21 studies were included. The SLNB identification rates are high with all the commonly used blue dyes. Furthermore, methylene blue is superior to iso-sulfan blue and Patent Blue V with respect to false-negative rates. The combined technique remains the most accurate and effective technique for SLNB. In order to standardize the SLNB technique, comparative trials to determine the most effective blue dye and national guidelines are required.

A prospective study comparing touch imprint cytology, frozen section analysis, and rapid cytokeratin immunostain for intraoperative evaluation of axillary sentinel lymph nodes in breast cancer

BACKGROUND

The intraoperative evaluation of axillary sentinel lymph nodes (SLNs) allows the surgeon to complete axillary dissection in 1 setting at the time of the primary breast surgery. However, to the authors' knowledge, there is no consensus regarding the optimal method for intraoperative evaluation of SLNs in breast cancer. The authors of this report prospectively compared touch imprint (TI) cytology with frozen section (FS) analysis and rapid cytokeratin immunostaining (RCI) of SLNs for the intraoperative evaluation of disease and compared the results with final pathologic examination (FP).

METHODS

Patients with invasive breast carcinoma who were diagnosed with lymph node-negative disease (based on preoperative clinical and sonographic evaluation with or without fine-needle aspiration of the indeterminate lymph nodes) and who subsequently were scheduled for lymphatic mapping were eligible to participate in this prospective protocol. TI and FS analysis were performed on all SLNs, and the lymph nodes were stained by the hematoxylin and eosin (H&E) method. RCI was performed using the enhanced polymer 1-step cytokeratin method. The results of TI, FS, RCI, TI plus FS, and FS plus RCI were compared with the results from FP, including 1 H&E stain and cytokeratin immunostain of the third level.

RESULTS

One hundred patients with invasive mammary carcinoma were accrued to the study. Eighty-five tumors were the ductal type, 8 tumors were lobular, 5 tumors were mixed ductal and lobular, 1 was an adenoid cystic tumor, and 1 tumor was metaplastic carcinoma. Seventy-two tumors were staged clinically as T1N0M0, 25 tumors were staged as T2N0M0, and 3 tumors were staged as T3N0M0. Metastatic carcinoma was detected in the SLNs by 1 or more methods, including TI, FS, RCI, and FP, in 20 tumors, which included 12 macrometastases and 8 micrometastases. TI detected 8 of 12 macrometastases (67%), FS detected 12 of 12 macrometastases (100%), RCI detected 12 of 12 macrometastases (100%), and FP detected 12 of 12 macrometastases (100%). TI detected 1 of 8 micrometastases (13%), FS detected 3 of 8 micrometastases (38%), RCI detected 4 of 8 micrometastases (50%), and FP detected 6 of 8 micrometastases (75%). The sensitivities of TI, FS, RCI, TI plus FS, and FS plus RCI (with FP as the gold standard) were 50%, 72%, 78%, and 83%, respectively, and the sensitivities of the same intraoperative methods were 45%, 75%, 80%, and 85%, respectively, with detection of metastatic disease by any method as the gold standard. The specificities of the different methods (with FP as the gold standard) were 100% for TI and 97.5% for FS, RCI, TI plus FS, and FS plus RCI. The specificity of each method was 100% when the detection of metastatic disease by any method was regarded as the gold standard. Although the difference in sensitivity between FS and TI was not statistically significant (P = .08), the difference between RCI and TI bordered on significance (P = .046); however, FS analysis plus RCI was significantly superior to TI (P = .03) and produced results comparable to those of FP.

CONCLUSIONS

The sensitivities of FS, RCI, TI plus FS, and FS plus RCI were better than the sensitivity of TI cytology of axillary SLNs. However, only the combination of FS and RCI was statistically superior to TI and generated results comparable to those of FP in SLNs. RCI can be completed within the time constraints for intraoperative use and, in conjunction with FS, can be useful for generating results closer to those generated by FP. FS analysis plus RCI have a role in the intraoperative evaluation of SLNs.

Intraoperative frozen section assessment of sentinel lymph nodes in the operative management of women with symptomatic breast cancer

BACKGROUND

Maximisation of the potential of sentinel lymph node biopsy as a minimally invasive method of axillary staging requires sensitive intraoperative pathological analysis so that rates of re-operation for lymphatic metastases are minimised. The aim of this study was to describe the test parameters of the frozen section evaluation of sentinel node biopsy for breast cancer compared to the gold standard of standard permanent pathological evaluation at our institution.

METHODS

The accuracy of intraoperative frozen section (FS) of sentinel nodes was determined in 94 consecutive women undergoing surgery for clinically node negative, invasive breast cancer (37:T1 disease; 43:T2; 14:T3). Definitive evidence of lymphatic spread on FS indicated immediate level II axillary clearance while sentinel node "negativity" on intraoperative testing led to the operation being curtailed to allow formal H&E analysis of the remaining sentinel nodal tissue.

RESULTS

Intraoperative FS correctly predicted axillary involvement in 23/30 patients with lymphatic metastases (76% sensitivity rate) permitting definitive surgery to be completed at the index operation in 87 women (93%) overall. All SN found involved on FS were confirmed as harbouring tumour cells on subsequent formal specimen examination (100% specificity and positive predictive value) with 16 patients having additional non-sentinel nodes found also to contain tumour. Negative Predictive Values were highest in women with T1 tumours (97%) and lessened with more local advancement of disease (T2 rates: 86%; T3: 75%). Of those with falsely negative FS, three had only micrometastatic disease.

CONCLUSION

Intraoperative FS reliably evaluates the status of the sentinel node allowing most women complete their surgery in a single stage. Thus SN can be offered with increased confidence to those less likely to have negative axillae hence expanding the population of potential beneficiaries.

Lymphatic mapping and sentinel lymph node biopsy in early-stage breast carcinoma: a metaanalysis

BACKGROUND

Lymphatic mapping with sentinel lymph node biopsy has the potential for reducing the morbidity associated with breast carcinoma staging. It has become a widely used technology despite limited data from controlled clinical trials.

METHODS

A systematic review of the world's literature of sentinel lymph node (SLN) biopsy in patients with early-stage breast carcinoma was undertaken by using electronic and hand searching techniques. Only studies that incorporated full axillary lymph node dissection (ALND), regardless of SLN results, were included. Individual study results along with weighted summary measures were estimated using the Mantel-Haenszel method. The correlations of outcomes with the study size, the proportion of positive lymph nodes, the technique used, and the study quality were evaluated.

RESULTS

Between 1970 and 2003, 69 trials were reported that met eligibility criteria. Of the 8059 patients who were studied, 7765 patients (96%) had successfully mapped SLNs. The proportion of patients who had successfully mapped SLNs ranged from 41% to 100%, with > 50% of studies reporting a rate < 90%. Lymph node involvement was found in 3132 patients (42%) and ranged from 17% to 74% across studies. The false-negative rate (FNR) ranged from 0% to 29%, averaging 7.3% overall. Eleven trials (15.9%) reported an FNR of 0.0, whereas 26 trials (37.7%) reported an FNR > 10%. Significant inverse correlations were observed between the FNR and both the number of patients studied (r = - 0.42; P < 0.01) and the proportion of patients who had successfully mapped SLNs nodes (r = - 0.32; P = 0.009).

CONCLUSIONS

Lymphatic mapping with SLN biopsy is used widely to reduce the complications associated with ALND in patients with low-risk breast carcinoma. This systematic review revealed a wide variation in test performance.

Meta-analysis of sentinel node imprint cytology in breast cancer

BACKGROUND

Intraoperative diagnosis of breast cancer metastases in axillary sentinel nodes is desirable to avoid a second operation for lymphadenectomy. Imprint or touch-preparation cytology is a popular technique that has high specificity and a wide range of sensitivity.

METHODS

A systematic search of electronic databases was performed. Included articles were assessed for methodological and reporting quality. Random-effects model pooled estimates of sensitivity and specificity were calculated. Single-variable and multivariable meta-regression analyses were performed for predictors of sensitivity.

RESULTS

Thirty-one studies were included; all were of good methodological quality but reporting quality varied. Pooled sensitivity of imprint cytology was 63 (95 per cent confidence interval (c.i.) 57 to 69) per cent and specificity was 99 (95 per cent c.i. 98 to 99) per cent. Pooled sensitivity for macrometastases was 81 per cent and that for micrometastases 22 per cent. Mean or median primary tumour size (P = 0.004), the prevalence of metastases (P = 0.103) and the proportion of micrometastases (P = 0.022) were significant risk factors in single-variable meta-regression analysis. Only the proportion of micrometastases remained significant in multivariable analysis. Frozen sectioning had better sensitivity than imprint cytology in three of four direct comparisons.

CONCLUSION

Imprint cytology is simple and rapid, and has good sensitivity for macrometastases. The significance of poor sensitivity for micrometastases will be determined by trials investigating their natural history.

Sentinel lymph node biopsy assessment using intraoperative imprint cytology in breast cancer patients: results of a validation study

OBJECTIVE

Sentinel lymph node biopsy (SLNB) in breast cancer patients is emerging as a promising minimally-invasive tool. There has been an exponential increase in the literature related to sentinel lymph nodes (SLN) in breast cancer patients, mainly from Western centres. This study was carried out to address issues relevant to breast cancer patients in developing countries, including the method of SLN detection, the role of imprint cytology in the assessment of SLN, and the role of SLNB in locally advanced breast cancer (LABC).

METHODS

This study included 76 women with breast cancer. The blue-dye method was used to identify the sentinel node. Touch imprint smears were prepared from the sectioned node, stained using the Jenner-Geimsa technique, and examined for tumour deposits.

RESULTS

Sentinel nodes were identified in 69 of 76 patients. The sensitivity, specificity and accuracy of SLNB in predicting axillary node status were 84.2%, 100% and 91.3%, respectively. The sensitivity, specificity and accuracy of intraoperative imprint cytology were 96.9%, 100% and 98.6%, respectively.

CONCLUSIONS

These results prove that high levels of SLN detection can be achieved using the blue-dye method alone. Its role in LABC patients needs further evaluation. In view of promising results, imprint cytology should be used more frequently as an alternative to frozen section for the assessment of sentinel nodes.

Pathological Evaluation of Sentinel Lymph Nodes for Breast Cancer

Recently, sentinel lymph node (SLN) biopsy has been employed to avoid unnecessary lymph node dissection, because SLN negativity for carcinoma metastases may imply an extremely low possibility of non-SLN involvement. Pathological evaluation is essential, but standardized procedures have not yet been determined. Intraoperative consultation, either by frozen section (multiple slices are desirable) or touch imprint cytology, are usually very useful. Their accuracy, however, is variable and depends on the procedures used, but specificity is characteristically 100%, and the missed metastatic focus is always quite minute. After fixation, multiple sections, immunohistochemistry, and their combination will be able to detect small metastatic foci more frequently. The clinical significance of small or submicro- or occult metastases have not yet been clarified, and further investigations are needed. If the SLN is positive for carcinoma metastases, both the procedure for detection and the size of the metastatic focus should be clarified on the pathological reports.

Pathological work-up of sentinel lymph nodes in breast cancer. Review of current data to be considered for the formulation of guidelines

Controversies and inconsistencies regarding the pathological work-up of sentinel lymph nodes (SNs) led the European Working Group for Breast Screening Pathology (EWGBSP) to review published data and current evidence that can promote the formulation of European guidelines for the pathological work-up of SNs. After an evaluation of the accuracy of SN biopsy as a staging procedure, the yields of different sectioning methods and the immunohistochemical detection of metastatic cells are reviewed. Currently published data do not allow the significance of micrometastases or isolated tumour cells to be established, but it is suggested that approximately 18% of the cases may be associated with further nodal (non-SN) metastases, i.e. approximately 2% of all patients initially staged by SN biopsy. The methods for the intraoperative and molecular assessment of SNs are also surveyed.

Effect of Increasing the Surface Sampled by Imprint Cytology on the Intraoperative Assessment of Axillary Sentinel Lymph Nodes in Breast Cancer Patients

As axillary sentinel nodes predict the nodal status and may allow dissection of the axilla on a selective basis we assessed the effects of increasing the surface sampled during intraoperative imprint cytology. Sentinel nodes from 110 patients identified with Patent blue and/or the high radioactivity due to the uptake of 99m-Tc-labeled colloidal albumin were analyzed via hematoxylin and eosin-stained touch preparations. Imprint cytology was performed either on bisected nodes (Protocol One; n = 55) or on sentinel nodes sliced into multiple pieces at 2- to 3-mm intervals (Protocol Two; n = 55). The sentinel nodes were submitted in toto to permanent step sectioning and immunostaining for cytokeratins. There were equal numbers of patients with involved nodes in the two groups assessed. With Protocols One and Two the imprints had sensitivities of 52 and 61 per cent, negative predictive values of 74 and 78 per cent, and false negative rates of 47 and 39 per cent, respectively. No macrometastasis missed by Protocol Two was absent from the surface sampled. These data suggest that increasing the surface sampled improves the proportion of involved sentinel nodes detected intraoperatively by imprint cytology, but a number of metastatic nodes still remain undetected by this method. The sampling of multiple surfaces is encouraged for a more accurate intraoperative assessment.

Combination of subareolar blue dye and peritumoral RI for sentinel lymph node biopsy

BACKGROUND

The identification rate of sentinel lymph nodes (SLNs) is variable because numerous different methods employing different tracers have been used for sentinel lymph node detection. The aim of this study was to determine the optimal technique for sentinel lymph node biopsy (SLNB).

METHODS

From May 1999 to December 2001, SLNB was performed for 376 patients with T1-3 and N0-1 primary breast cancer using blue dye alone, radioisotope (RI) alone and combination of RI and blue dye. Two hundred sixty-eight patients underwent SLNB using blue dye alone. They were divided into 4 groups (Group A: n=50; peritumoral injection, Group B: n=83; the first half to receive subareolar injection, Group C: n=83; the second half to receive subareolar injection, and Group D: n=52; small incision according to an axillary skin landmark). One hundred eight patients underwent SLNB using RI. Tin colloid was used in 49 cases (Tin Colloid Group) and phytate in 59 cases (Phytate Group). Among them, 29 patients underwent injection of RI alone and 79 patients received a combination of RI and blue dye.

RESULTS

The identification rates of SLN using blue dye alone were 60%, 82%, 92% and 79% in Groups A, B, C and D, respectively. The identification rates of SLN in patients receiving RI alone and in those receiving combination of RI and blue dye were 40% and 89%, respectively, in Tin Colloid Group, and 92% and 94%, respectively, in Phytate Group.

CONCLUSION

When using blue dye alone, subareolar injection provided a better identification rate than peritumoral injection. The combination of peritumoral phytate and subareolar blue dye provided the best identification rate (94%) in all the groups. The combination of intraparenchymal phytate and subareolar blue dye was the most efficient technique for sentinel node biopsy in breast cancer patients.

Complete sectioning of axillary sentinel nodes in patients with breast cancer. Analysis of two different step sectioning and immunohistochemistry protocols in 246 patients

AIMS

To evaluate two detailed step sectioning protocols for sentinel lymph nodes (SLNs).

METHODS

After vital dye or combined dye and radiocolloid guided biopsy, SLNs were fixed in formalin and embedded in paraffin wax. In protocol A, SLNs from 123 patients were sectioned in steps of 50-100 micro m, whereas in protocol B, SLNs from 123 patients were sectioned at steps of 250 micro m. Epithelial marker immunohistochemistry (IHC) was performed on multiple levels in cases with negative haematoxylin and eosin findings.

RESULTS

In groups A and B, 74 and 47 patients were found to have tumour cells in their axillary SLNs, and 19 (28%) and 18 (19%) patients, respectively, were upstaged as compared with the standard histological assessment. Nodal involvement detected by deeper sections was often micrometastatic or in isolated tumour cells

CONCLUSIONS

Serial sectioning and IHC are recommended for the evaluation of SLNs. The optimal extent of the histopathological work up should be studied further.

Sentinel lymph node biopsy in breast cancer: an overview of the Japanese experience

This paper reviews the Japanese literature regarding sentinel lymph node (SLN) biopsy in an attempt to provide an overview of existing controversies and to suggest a method for the identification of the SLN and the detection of micrometastases in the SLN to eliminate unnecessary axillary lymph node dissection (ALND). The combined dye- and gamma probe-guided method resulted in the accurate identification of the SLN in 96% of patients, compared with 80% when the dye-guided method alone was used. Although neither 99m-Tc sulfur colloid nor 99m-Tc colloidal albumin is commercially available in Japan, 99m-Tc stannous phytate and 99m-Tc rhenium colloid appear to be ideal tracers for identifying SLNs. Moreover, subdermal injection over the primary tumor or subareolar injection was found to enhance SLN identification, although these injection routes do not lead to detection of internal mammary SLNs. Furthermore, the accuracy of SLN diagnosis using frozen sections as well as imprint cytology improved with an increase in the number of sections, and could attain a sensitivity comparable to that obtained with routine histologic examination of permanent sections. As a result, several surgeons have begun to offer the option of forgoing ALND to patients with negative SLN. Although subsequent relapse in the axilla has not yet been reported, longer follow-up periods are needed to assess accurately the incidence of axillary failure in these negative SLN patients.

Sentinel lymph node biopsy and breast cancer

BACKGROUND AND METHOD

This paper reviews and discusses the feasibility and accuracy of sentinel lymph node (SLN) biopsy in breast cancer. A standardized method of identifying the SLN and detecting micrometastases is suggested, along with a strategy for the elimination of routine axillary lymph node dissection (ALND).

RESULTS

Although the SLN can be identified successfully by experienced practitioners using either the dye-guided or gamma probe-guided method, identification is facilitated when the two techniques are combined. To improve the likelihood of spotting metastases in the SLN, it is desirable to perform step sectioning combined with haematoxylin and eosin staining and immunohistochemistry of permanent and frozen sections. SLN biopsy is as accurate for T2 tumours as it is for T1 tumours. However, it is highly unlikely that all false-negative cases can be eliminated, even by detailed histological examination. Nevertheless, patients with T1 tumours with micrometastases in the SLN have shown no evidence of tumour in the non-sentinel nodes. In other words, ALND can be avoided in these patients, even if histological examination of the SLN fails to detect micrometastasis.

CONCLUSION

In practice, routine ALND can be avoided in patients with T1 tumours when the identified SLN proves to be histologically negative. However, investigation of long-term regional controls and of survival in a prospective randomized trial is necessary before SLN biopsy can replace routine ALND, particularly for patients with T2 tumours.

Clinical and pathologic factors predicting axillary lymph node involvement in breast cancer

The diagnosis of axillary disease remains a challenge in the management of breast cancer and is a subject of controversy. In 1998, the Japanese Breast Cancer Society conducted a study assessing axillary lymph node involvement in breast cancer. The study included (a) clinical assessment by pre-operative imaging modalities, (b) histologic assessment for peritumoral lymphatic invasion, (c) biologic assessment by gelatinolytic activity using film in situ zymography, and (d) sentinel lymph node (SLN) biopsy. Clinical assessments by CT, PET, and US as well as biologic assessment were limited in their ability to detect axillary lymph node disease, although these imaging techniques may be useful to exclude node-positive patients from the need for SLN biopsy. Histologic assessment for peritumoral lymphatic invasion was useful, particularly for detecting false-negative cases by SLN biopsy. Nevertheless, the utility of SLN biopsy in assessing axillary nodal status was confirmed. Axillary lymph node dissection (ALND) can be avoided in patients with a small tumor and a negative SLN. However, further studies will be required to investigate the value of SLN biopsy for predicting regional control and survival before it can replace routine ALND as the optimal staging procedure for operable breast cancer.

Sentinel lymph node biopsy in breast cancer using blue dye with or without isotope localization

BACKGROUND

The purpose of this study was to determine the feasibility of sentinel lymph node (SLN) biopsy using blue dye with or without isotope localization to predict the presence of axillary and internal mammary lymph node (IMN) metastases in patients with breast cancer. We also investigated whether multiple sectioning of the SLN could improve the accuracy of frozen section examination.

METHOD

One-hundred twenty-six patients underwent dye-guided or dye- and gamma probe-guided SLN biopsy followed by complete axillary lymph node dissection (ALND). No ALND was performed in the 14 patients with small tumors and a negative SLN. In addition, 69 patients underwent IMN biopsy.

RESULTS

The axillary SLN was identified in 123 of 140 (88%) patients. An accuracy rate of 90% was obtained by frozen section examination of the SLN, which increased to 100% in patients examined with a greater number of sections. Lymphatic flow to the IMN and/or a radioactive hot spot in the IMN was found in 9 of 102 (9%) patients, while a hot node was detected using a gamma probe in only 2 of these patients. No involvement of the IMNs was found histologically in these 9 patients. IMN involvement was found in 7 of 61 (11%) patients without lymphatic flow to the IMNs or a hot spot by lymphoscintigraphy or who did not undergo lymphoscintigraphy.

CONCLUSION

ALND can be avoided in patients with small breast cancers and a negative SLN. SLN biopsy guided by lymphatic mapping is unreliable for identifying metastases to IMNs.

The Potential Value of Intraoperative Imprint Cytology of Axillary Sentinel Lymph Nodes in Breast Cancer Patients

Axillary sentinel nodes predict the node status and may allow dissection of the axilla on a selective basis. Seventy-two sentinel nodes from 60 patients identified with Patent blue and/or the high radioactivity due to the uptake of 99m-Tc-labeled colloidal albumin were bisected for hematoxylin and eosin-stained touch preparations. The sentinel nodes were submitted in toto for permanent step sections and immunostained for cytokeratins. The imprints had a sensitivity of 83 per cent, a negative predictive value of 86 per cent, and a false negative rate of 17 per cent when the cut surface histology was considered. These corresponding values were 59, 68, and 41 per cent on a patient basis when the whole sentinel node histology was considered as many micrometastases did not appear in the cut surface sampled by the imprints. Although up to two-fifths of patients with tumor cells in the sentinel lymph nodes may be undetected by the method imprint cytology is valuable in the intraoperative assessment of sentinel nodes. This series suggests that 78 per cent of the patients can be adequately selected for a one-step axillary operation on the basis of intraoperative imprints. Results may be improved if the surface sampled is appropriately large and well selected.

Axillary staging of breast cancer and the sentinel node

Pathological aspects of axillary nodal staging of breast cancer and in particular sentinel lymph node (SLN) biopsy are reviewed. SLN biopsy seems an almost ideal staging procedure because it has both high accuracy and a low false negative rate. It may also allow a cost effective use of more sensitive methods of metastasis detection. However, the biological relevance of metastases detected only by modern tools remains to be elucidated. This review focuses on standard axillary staging and the histopathological investigation of SLNs, with emphasis on the intraoperative setting. Future trends including ancillary studies, quality control issues, prediction of non-SLN involvement, and suggestions concerning the minimum requirements for the histology of axillary SLNs are also discussed.

A multicenter validation study of sentinel lymph node biopsy by the Japanese Breast Cancer Society

Several pilot studies have indicated that SLN biopsy can be used to identify axillary lymph node metastases in patients with breast cancer. To confirm this finding, a multicenter study in a variety of practice settings was performed. A total of 674 patients with breast cancer at five institutions were enrolled. The techniques of SLN identification included the vital dye-guided and the vital dye- and gamma probe-guided methods. The SLN was removed, and complete axillary lymph node dissection (ALND) was performed. SLN and ALND specimens were examined separately. The SLN was successfully identified in 214 (94%) of 227 patients using the combined dye- and gamma probe-guided methods. The SLN was identified in 332 (74%) of 447 patients using vital dye-guided method alone. Patient age of at least 21 years, medially located primary tumor, and clinically positive nodes were correlated with failure to identify the SLN. The accuracy of SLN biopsy for the detection of metastatic disease was 96% (522 of 546), and the sensitivity was 90% (203 of 226). Accuracy of 100% was achieved in the patients with tumors less than 1.6 cm in diameter. All 23 false negative results occurred with larger primary tumors. SLN biopsy can accurately predict the presence or absence of axillary lymph node metastases, particularly in patients with small (< or = 1.5 cm) breast cancers.

Comprehensive review of sentinel lymphadenectomy in breast cancer

Sentinel lymph node dissection (SLND) is a minimally invasive technique to stage axillary lymph nodes in breast cancer. The complications associated with SLND are minimal, especially when compared to routine axillary lymph node dissection (ALND), and it can be performed with an overall identification rate of greater than 90% and a false-negative rate less than 5%. Despite this, SLND is not ready to replace routine axillary dissection, since we have no long-term results for these patients. What the clinical recurrence rates will be in women who undergo SLND only and how that will translate into survival rates has yet to be discovered. SLND is also a difficult technique to perform, as documented in the early SLND studies. It is imperative that each individual surgeon perform a series of cases in which SLND is combined with immediate ALND, so that identification rates and false-negative rates can be determined. Once a track record of successfully performed SLND has been established, SLND can be solely used for node-negative women. It is strongly recommended that all surgeons join one of the National Cancer Institute (NCI)-sponsored clinical trials for SLND in early breast cancer, so that many of these questions concerning SLND can finally be answered.