Sentinel node biopsy in breast cancer

Sentinel Lymph Node Mapping and Biopsy for Breast Cancer: A Review of the Literature Relative to 4791 Procedures

The status of axillary nodes is the most important prognostic factor in breast cancer to select patient subgroups for adjuvant chemotherapy; the current standard of care for surgical management of invasive breast cancer is complete removal of the tumor by either mastectomy or lumpectomy followed by axillary lymph node dissection (ALND). The recent introduction of intraoperative lymphatic mapping and sentinel lymph node biopsy (SLND) represents a major new opportunity for appropriate and less invasive surgical management of many tumors. There is an almost uniformly enthusiasm concerning the potential of this technique in breast carcinoma management, shown by published data. A peculiar attention to the so-called “sentinel node debate” in breast cancer surgery is a constant in the last years issues of the major medical journals. Even patients have become more aware about medical enthusiasm and their request of concise information on the topic and the possibilities of this approach is an increasing reality in medical practice.

The aim of this paper is to review recent literature to offer an overview about the main controversial methodological aspects and a wide analysis of reported results. The most significative international literature papers from Medline were retrieved from 1993 to September 1999, and 4782 procedures were analysed. This extensive review of the literature has confirmed accuracy, feasibility and reliability of the SN detecting technique in axillary mapping. Provided a good proficiency in SN localisation and pathological evaluation, human resources and efforts should be mainly focused on its clinical validation as an alternative to ALND instead of on further phase I–-II clinical studies.

Study of Sentinel Lymph Node in Breast Cancer: Our Experience in 46 Cases

At the Surgery Department of Biella 46 patients were enrolled in a study on the sentinel lymph node (SN) in the period from 1 January 1999 to 30 September 1999. The aim of the study was to determine, on the basis of our own experience, the percentages of accuracy and concordance, and compare them with case series abroad and in Italy; in addition, we sought to establish a possible correlation between certain features of breast cancer and positivity of the axilla. The method utilized was lymphoscintigraphy and gamma probe. Fifteen cases with positive axillary lymph nodes and 12 cases with positive sentinel lymph nodes were found; there were no false positive and three false negative results. No migration of the tracer was observed with lymphoscintigraphy in two cases. The percentage of concordance obtained was 93.2% in the complete series and 96.5% in the subseries that excluded the learning curve. Comparing the percentage of concordance of our case series with those abroad and in Italy, an average overlapping percentage was obtained. The percentage of accuracy obtained in our study was 95.7%, which is slightly higher than the average of percentages of the case series abroad and in Italy.

Tumor differentiation as related to sentinel lymph node status in gastric cancer

AIM: To investigate the influence of tumor grade on sentinel lymph node (SLN) status in patients with gastric cancer (GC).

METHODS: We retrospectively studied 71 patients with GC who underwent SLN mapping during gastric surgery to evaluate the relationship between SLN status and tumor grade.

RESULTS: Poorly differentiated tumors were detected in 50/71 patients, while the other 21 patients had moderately differentiated tumors. SLNs were identified in 58/71 patients (82%). In 41 of the 58 patients that were found to have stained nodes (70.7%), the tumor was of the poorly differentiated type (group I), while in the remaining patients with stained nodes 17/58 (29.3%), the tumor was of the moderately differentiated type (group II). Positive SLNs were found in 22/41 patients in group I (53.7%) and in 7/17 patients in group II (41.2%) (P = 0.325). The rate of positivity for the SLNs in the two groups (53.7% vs 41.2%) was not statistically significant (P = 0.514).

CONCLUSION: Most of our patients were found to have poorly differentiated adenocarcinoma of the stomach and there was no correlation between tumor grade and SLN involvement.

The false-negative rate of sentinel node biopsy in patients with breast cancer: a meta-analysis

BACKGROUND

In sentinel node surgery for breast cancer, procedural accuracy is assessed by calculating the false-negative rate. It is important to measure this since there are potential adverse outcomes from missing node metastases. We performed a meta-analysis of published data to assess which method has achieved the lowest false-negative rate.

METHODS

We found 3,588 articles concerning sentinel nodes and breast cancer published from 1993 through mid-2011; 183 articles met our inclusion criteria. The studies described in these 183 articles included a total of 9,306 patients. We grouped the studies by injection material and injection location. The false-negative rates were analyzed according to these groupings and also by the year in which the articles were published.

RESULTS

There was significant variation related to injection material. The use of blue dye alone was associated with the highest false-negative rate. Inclusion of a radioactive tracer along with blue dye resulted in a significantly lower false-negative rate. Although there were variations in the false-negative rate according to injection location, none were significant.

CONCLUSIONS

The use of blue dye should be accompanied by a radioactive tracer to achieve a significantly lower false-negative rate. Location of injection did not have a significant impact on the false-negative rate. Given the limitations of acquiring appropriate data, the false-negative rate should not be used as a metric for training or quality control.

Intraoperative assessment of sentinel lymph nodes in breast cancer

Background

Sentinel lymph node biopsy (SLNB) reduces the morbidity of axillary clearance and is the standard of care for patients with clinically node-negative breast cancer. The ability to analyse the sentinel node during surgery enables a decision to be made whether to proceed to full axillary clearance during primary surgery, thus avoiding a second procedure in node-positive patients.

Methods

Current evidence for intraoperative sentinel node analysis following SLNB in breast cancer was reviewed and evaluated, based on articles obtained from a MEDLINE search using the terms ‘sentinel node’, ‘intra-operative’ and ‘breast cancer’.

Results and conclusion

Current methods for evaluating the sentinel node during surgery include cytological and histological techniques. Newer quantitative molecular assays have been the subject of much recent clinical research. Pathological techniques of intraoperative SLNB analysis such as touch imprint cytology and frozen section have a high specificity, but a lower and more variably reported sensitivity. Molecular techniques are potentially able to sample a greater proportion of the sentinel node, and could have higher sensitivity.

[Sentinel lymph node biopsy in breast neoplasms]

BACKGROUND/AIM

Sentinel node (SN) is the first draining node from the malignant tumor site. In the last decade, sentinel node biopsy (SNB) has been introduced as an alternative to axillary dissection in breast cancer. I n patients with negative SNB (sentinel node uninvolved with malignancy) axillary dissection is not recommended. The aim of this stady was defining the indications for SNB, and SNB principles, as well as the survey of our first experiences.

METHODS

In the period from 2004 to 2008, we performed 78 SNBs in 75 patients (72 females, 3 males) with breast cancer. Indications for SNB were T1-2 and N0 lesions according to TNM classification (Tumor, Nodus Methastasis). In all cases, lymphoscintigraphy was done first, and then SNB with double contrast (methylen blue and technetium - Tc-99). In 57 (73%) cases, one SN was confirmed, and in 21 (26.9%) 2 nodes.

RESULTS

In 58 (74.3%) SNB, SN pathohistology was negative, ie. there were no cancer metastases. In this group of patients, axillary dissection was not done in 47 (81%) SNB. In the remaining 11 (18.9%), lymphonodal dissection level I and II was done after SNB, regardless of the presence or no presence of metastases within SN. All the cases were monitored from six months to one year of the operation and disease progression was not observed.

CONCLUSION

Sentinel node biopsy is an acceptable method of breast cancer diagnosis and a good alternative to lymphonodal dissection if there are no metastases within SN. The technique is relatively simple, but requires team work of experienced specialists: surgeons, nuclear medicine specialists and anesthesiologists. Our first experiences suggest a high degree of reliability of the method in selected patients and with well trained team of doctors.

Sentinel lymph node biopsy: technique validation at the Setúbal Medical Centre, Portugal

Aims:

To evaluate the accuracy of sentinel lymph node biopsy in breast cancer patients at this institution, using combined technetium-99m (^99mTc) sulphur colloid and patent blue vital dye.

Methods:

From March 2007 to July 2008, 50 patients with a tumour of less than 3 cm and with clinically negative axillary lymph nodes underwent sentinel lymph node biopsy (SLNB), followed by axillary lymph node dissection (ALND). Sub-areolar ^99mTc sulphur colloid injection was performed the day before surgery, and patent blue vital dye was also injected sub-areolarly at least 5 minutes before surgery. Sentinel lymph node was identified during the surgical procedure, using a gamma probe and direct vision. All sentinel nodes underwent frozen section analysis. Later haematoxylin and eosin staining and immunohistochemical analysis were performed. Finally, SLNB was compared with standard ALND for its ability to accurately reflect the final pathological status of the axillary nodes.

Results:

The sentinel lymph node (SLN) was identified in 48 of 50 patients (96%). The number of sentinel lymph nodes ranged from one to four (mean 1.48) and non-sentinel nodes ranged from seven to 27 (mean 14.33). Of the 48 patients with successfully identified SLNs, 29.17% (14/48) were histologically positive. Sensivity of the SLN to predict axilla was 93.75%; accuracy was 97.96%. The SLN was falsely negative in one patient—6.25% (1/16).

Conclusions:

The SLNB represents a major advance in the surgical treatment of breast cancer as a minimally invasive procedure predicting the axillary lymph node status. This validation study demonstrates the accuracy of the SLNB and its reasonable false negative rate when performed in our institute. It can now be used as the standard method of staging in patients with early breast cancer at this institution.

Biphasic anaphylactic reaction to blue dye during sentinel lymph node biopsy

Background

Lymphazurin 1% blue dye can cause a severe anaphylactic reaction in approximately 1–3% of patients.

Case presentation

We describe a case of intraoperative anaphylaxis resulting from Lymphazurin 1% blue dye. A 48-year old woman undergoing a mastectomy with sentinel lymph node biopsy experienced a biphasic anaphylactic reaction with two episodes of hypotension at 15 minutes and 2 hours, respectively, after injection of the blue dye. The late phase was initially refractory to epinephrine.

Conclusion

Early recognition, aggressive hemodynamic management, and prolonged monitoring are indicated in these patients to watch for a potential second phase anaphylactic reaction.

The MSKCC nomogram for prediction the likelihood of non-sentinel node involvement in a German breast cancer population

OBJECTIVE

To assess whether the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram for prediction of NSLN metastasis is useful in a German breast cancer population and whether the characteristics of the breast tumor and the sentinel lymph node (SLN) are able to predict the likelihood of non-sentinel lymph node (NSLN) metastasis.

METHODS

A total of 545 patients with primary breast cancer and SLN examination were evaluated. The MSKCC nomogram was applied to 98 patients with a positive SLN who subsequently had completion axillary lymph node dissection (ALND). Predictive accuracy was assessed by calculating the area under the receiver-operator characteristic (ROC) curve. The collective was evaluated by correlating the prevalence of NSLN and SLN metastasis to pathological features.

RESULTS

The MSKCC nomogram achieved a ROC of 0.58 indicating a bad accuracy of the nomogram. Tumor size, histology, lymphovascular infiltration, multifocality, Her-2-neu positivity, and nuclear grade correlated with the probability of SLN metastasis. Histology and primary tumor localization correlated significantly with the probability of NSLN metastasis.

CONCLUSIONS

The MSKCC nomogram did not provide a reliable predictive model in our study population. However, the likelihood of SLN metastasis correlated with the presumed risk factors and no obvious differences between the MSKCC population and our population could be seen. In order to achieve interinstitutional reproducibility, standardization of surgical procedure and of the pathological assessment of the SLN is desirable.

Subareolar blue dye only injection sentinel lymph node biopsy could reduce the numbers of standard axillary lymph node dissection in environments without access to nuclear medicine

PURPOSE

The gold standard of axillary sentinel lymph node biopsy (SLNB) in breast cancer is the combination of radioactive colloid and blue dye injection. Worldwide, numerous hospitals without access to radioactive tracers still perform a routine complete axillary lymph node dissection (ALND). We retrospectively analyzed the false negative rate and identification rate of SLNB with injection of blue dye in the absence of radioactive colloid and compared the subareolar (SA) and the peritumoral (PT) injection.

PATIENTS AND METHODS

Two hundred and fourteen patients with clinically node negative unifocal breast cancer of up to 3 cm in size who underwent SLNB followed by ALND were included. Patent Blue V was injected at the SA site in 120 patients or at the PT site in 94 patients.

RESULTS

Thirty-seven (31%) patients in the SA group and 28 (29.8%) in the PT group were node-positive by ALND. The mean number of SLNs identified was 3.1 in the SA group and 1.6 in the PT group. The SLN identification rate was 91.7% for the SA group and 80.9% for the PT group (P = 0.017). The false negative rate was 3.6% in the SA group and 11.8% in the PT group (P = 0.032).

CONCLUSIONS

Our study shows an acceptable low false negative rate for the SA blue dye only injection and confirms the higher identification rate of SA versus PT localisation. This technique could have spared 67.5% (81 out of 120) of our patients the ALND and could replace ALND of early breast cancer patients in environments without access to nuclear medicine.

Sentinel lymph node mapping for primary breast cancer

The tumor status of the axillary lymph nodes is the single most important predictor of survival for patients with primary breast cancer. Because of its essential role in staging, regional control, and perhaps survival, axillary lymph node dissection (ALND) has long been the standard of care for patients with operable breast cancer. During the past decade, the introduction and development of sentinel lymph node dissection (SLND) for primary breast cancer have allowed surgeons to determine the tumor status of the axilla without a standard level I and II ALND. Several well-designed studies have documented that SLND is an effective way of assessing axillary nodal status with minimal morbidity and high accuracy. We address the current status and future directions of SLND for primary breast cancer.

Is there an indication for sentinel node biopsy in patients with ductal carcinoma in situ of the breast? A review

Ductal carcinoma in situ (DCIS) of the breast is defined as a proliferation of malignant epithelial cells within breast ducts without evidence of invasion through the basement membrane. The detection rate of DCIS of the breast has dramatically increased since the mid-1980s as the result of the widespread use of screening mammography. DCIS currently represents about 15-25% of all breast cancers detected in population screening programmes. Although inherently a non-invasive disease, occult invasion with the potential of lymph node metastases may occur. Where performing an axillary lymph node dissection-or-not for DCIS used to be an important dilemma, the same now holds for the sentinel node biopsy. This article reviews the potential role of the sentinel node biopsy (SNB) in patients with DCIS. We conclude that based on the current literature, there is in general no role for a SNB in DCIS. A SNB should only be considered in patients with an excisional biopsy diagnosis of high risk DCIS (grade III with palpable mass or large tumour area by imaging) as well as in patients undergoing mastectomy after a core or excisional biopsy diagnosis of DCIS, although SNB may be contraindicated in many of the latter patients because of lesion size and/or multifocality. Even in these patients the value of a positive SN, containing mostly isolated tumour cells, is questionable.

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.

The role of axillary lymph node dissection in breast cancer patients with sentinel lymph node micrometastases

AIM

To identify by means of clinical and histopathological features a subset of breast cancer patients with sentinel lymph-node (sN) micrometastases and metastatic disease confined only to the sN in order to spare them an unnecessary axillary lymph node dissection (ALND).

MATERIALS AND METHODS

From January 1998 to December 2004, 116 patients with sN micrometastases underwent standard ALND for early-stage (T1-2 N0 M0) invasive breast cancer; clinical and histopathologic parameters were prospectively collected and evaluated by means of univariate and logistic regression analysis in order to identify which patients with sN micrometastases were free of metastasis in axillary non-sN.

RESULTS

Sixteen of 116 patients with sN micrometastases had tumour involvement of non-sN, with six and 10 patients having non-sN micrometastases and macrometastases, respectively. None of 19 patients with primary tumour measuring </= 10 mm had tumour-positive non-sN; moreover, none of 15 patients with G1 tumours had non-sN metastases. The mean tumour size in patients with non-sN involvement was 21.3 mm (range, 12-40 mm). Univariate test of association between clinical and histopathologic features and non-sN status showed that the primary tumour size (P=0.005) and the presence of lymphovascular invasion (P=0.000) were the only significant predictors of non-sN involvement. By logistic regression, primary tumour size (P=0.011), lymphovascular invasion (P=0.001), and size of sN micrometastases were the only variables remaining into the model, although the latter parameter was not statistically significant.

CONCLUSIONS

In patients with sN micrometastases, primary tumour size and lymphovascular invasion significantly predict non-sN status; notably, no patient with T1a-T1b and/or G1 tumours had non-sN metastases so that they could be spared an unnecessary ALND.

Predictors for nonsentinel node involvement in breast cancer patients with micrometastases in the sentinel lymph node

Sentinel lymph node (SLN) biopsy in breast cancer allows for a more thorough pathologic assessment with serial sectioning and cytokeratin staining. This has resulted in increased detection of micrometastatic disease (tumor size < 2 mm) in the SLN. Unfortunately, the value of completion axillary dissection after finding micrometastatic disease in the SLN remains poorly defined. Over a 2-year period, a prospective database of 305 patients who underwent SLN biopsy for breast cancer at Baylor University Medical Center was reviewed. Eighty-four (27.5%) of the patients had evidence of metastatic disease in the SLN. Twenty-four of the 41 patients identified as having micrometastatic disease in the SLN underwent completion axillary lymph node dissection. In these patients, all nonsentinel nodes were further studied by serial sectioning and immunohistochemistry. The median age of these 24 patients was 52 years (range, 34-83). Their primary tumor stages were T1a and T1b (n = 5), T1c (n = 15), and T2 (n = 4). A total of 328 nonsentinel lymph nodes were examined, including 225 from patients with infiltrating ductal carcinoma (n = 17) and 103 from patients with infiltrating lobular carcinoma (n = 7). In the patients with infiltrating ductal carcinoma, no additional nodal metastases were identified, while in those with infiltrating lobular carcinoma, additional nodal disease was found in 5 lymph nodes (2 of 12 patients, 17%). Primary tumor characteristics were not predictive of additional nodal disease. These data suggest that patients with micro-metastasis in the SLN from infiltrating lobular carcinoma have a significant risk of harboring additional nodal disease and should undergo completion axillary dissection. However, those with micrometastatic disease from infiltrating ductal carcinoma have a very low incidence of additional metastasis and may not need completion axillary dissection.

Evaluation of sentinel node identification with isosulfan blue in gastric cancer

AIMS

The aim of this study was to clarify whether the metastasis of gastric cancer can be detected by identifying the sentinel lymph nodes (SNs) using only lymphatic dye.

METHOD

The study was based on 101 patients clinically diagnosed with T1 and T2 gastric cancer. Isosulfan blue was intraoperatively injected within the submucosal layer around the lesion through an endoscope and blue stained nodes (BNs) were identified as SNs and harvested. Standard radical gastrectomy with D2 lymphadenectomy was performed on all patients and SNs and other nodes were evaluated.

RESULTS

Out of 101 patients, 21 had lymph-node metastases. The accuracy of SN identification was 97.0% (98/101) and the metastasis detection rate was 85.7% (18/21). With improvement of the manoeuvre in the latter 84 cases, the detection rate was elevated up to 100.0% (18/18), as was the accuracy (84/84).

CONCLUSION

The sentinel concept using lymphatic dye is applicable to gastric cancer, but the identification of SNs with lymphatic dye requires some practice. Furthermore, the issue of intraoperative metastasis detection remains to be resolved.

Factors predicting the sentinel and non-sentinel lymph node metastases in breast cancer

The sentinel lymph node (SLN) is the only focus of axillary metastasis in a significant proportion of patients. In this single institutional study, clinicopathologic characteristics were investigated to determine the factors predicting the status of a SLN biopsy and the metastatic involvement of non-SLNs. Data were retrospectively reveiwed for 400 consecutive patients with clinical T1/T2 N0 breast cancer who underwent a SLN biopsy including axillary and/or internal mammary lymph nodes. The SLNs were evaluated by using the new AJCC staging criteria following multiple sectioning and immunohistochemical (IHC) analyses of nodes. The SLN contained metastases in 148 patients (38.5%) including 18 patients (12.2%) with micrometastases (<or=0.2 mm) and 130 patients (87.8%) with macrometastases (>0.2 cm). Five patients had isolated tumor cells detected by IHC (<or=0.2 mm, N(0i)). Patients with tumor size more than 2 cm (T1, 29.8% versus T2, 51.6%; OR=2.31, 95% CI, 1.50-3.56) and lymphovascular invasion (LVI-, 30.3% versus LVI+, 51.3%; OR=2.07, 95% CI, 1.34-3.19) were more likely to have positive SLNs in both univariate and multivariate analyses. Among patients with a positive SLN biopsy, those with T2 tumors (versus T1; 63.1% versus 36.9; OR=2.93, 95% CI, 1.43-6.04), macrometastases in SLNs (versus micrometastases; 88.9% versus 11.1%; OR=8.83; 95% CI, 1.82-42.87) and extracapsular node extension (versus without extracapsular node extension; 65.4% versus 34.6%; OR, 2.23; 95% CI, 1.05-4.72) were more likely to have non-SLN metastases in both univariate and multivarite analyses. These results indicate that clinicopathologic factors might be helpful to select patients who were less likely to have negative SLN or non-SLNs. However, additional factors are still needed to be identified to omit surgical axillary staging.

Blue-dye technique complements four-node sampling for early breast cancer

AIMS

To examine four-node axillary sampling assisted by a blue dye (4NAS/dye) technique as a sentinel node biopsy (SNB) for breast cancer.

METHODS

Lymphatic mapping was performed by injection of patent blue for 33 consecutive cases with breast cancer. Axillary sampling was performed until four nodes were obtained. This was followed by back-up axillary lymph node dissection to examine the feasibility of 4NAS/dye. The same study with 30 cases was conducted at an independent hospital to confirm the feasibility of this method. This method was then applied to 101 consecutive clinically node-negative patients to avoid axillary-node dissection, with intraoperative diagnosis made by frozen section examination.

RESULTS

The median numbers of blue-stained nodes and nodes excised by 4NAS/dye were 1.7 and 3.4, respectively. The identification rate of sentinel lymph nodes (SNs) was 81.8% using the dye alone and 97.0% when the combination was used. Pathological examination revealed that the nodal status was correctly predicted by the dye alone in 62.5% of cases with metastasis, whereas in 100% by 4NAS/dye. The dye alone was not sufficient to identify SNs, especially in cases with prior excisional biopsy. The identification rate of SNs and the accuracy rate in another feasibility study were 100% and 92.5% in 30 consecutive cases, respectively. 4NAS/dye successfully detected SNs in 100 of 101 cases of the subsequent observational study with an acceptable post-operative axillary morbidity and thus succeeded as an SNB.

CONCLUSIONS

The 4NAS/dye method is reliable for the detection of SNs. This method could be applied to observational studies without radio-isotope.

A critical review of variables affecting the accuracy and false-negative rate of sentinel node biopsy procedures in early breast cancer

Radionuclide sentinel lymph node localization and biopsy is a staging procedure that is being increasingly used to evaluate patients with invasive breast cancer who have clinically normal axillary nodes. The most important prognostic indicator in patients with invasive breast cancer is the axillary node status, which must also be known for correct staging, and influences the selection of adjuvant therapies. The accuracy of sentinel lymph node localization depends on a number of factors, including the injection method, the operating surgeon's experience and the hospital setting. The efficacy of sentinel lymph node mapping can be determined by two measures: the sentinel lymph node identification rate and the false-negative rate. Of these, the false-negative rate is the most important, based on a review of 92 studies. As sentinel lymph node procedures vary widely, nuclear medicine physicians and radiologists must be acquainted with the advantages and disadvantages of the various techniques. In this review, the factors that influence the success of different techniques are examined, and studies which have investigated false-negative rates and/or sentinel lymph node identification rates are summarized.

Predictors of positive axillary lymph nodes in breast cancer patients with metastatic sentinel lymph node

INTRODUCTION

Breast cancer with metastatic sentinel lymph nodes (SLN) may have clinico-pathologic factors associated with the presence of positive non-sentinel axillary nodes (NSLN). The aim of the present study was to determine factors that predict involvement of NSLN in breast cancer patients with positive SLN.

MATERIAL AND METHODS

A prospective database search identified 80 patients who underwent SLN biopsy for invasive breast cancer between January 1999 and August 2002. Clinico-pathologic data was analyzed to determine factors that predicted additional positive axillary nodes.

RESULTS

A total of 23 patients had positive SLN and underwent conventional axillary lymph node dissection. Statistical analysis revealed that lympho-vascular invasion (p~0.00000), SLN metastasis >2 mm (p=0.002), and the presence of extra-nodal involvement (p=0.002), were positive predictors of the metastatic involvement of NSLN.

CONCLUSIONS

The likelihood of positive NSLN correlates with pathologic parameters such as the presence of lympho-vascular invasion, size of the SLN metastasis, and extra-nodal involvement. These data may be helpful with the regard to the decision to undertake axillary dissection in breast cancer patients with metastatic sentinel lymph nodes.

Sentinel Lymph Node Biopsy or Detection of Micrometastasis in Bone Marrow: Which Might Be an Alternative to Axillary Lymph Node Dissection in Breast Cancer Patients?

Axillary lymph node status has limited prognostic significance in breast cancer patients and much improvement can be made. Sentinel lymph node biopsy is emerging as an alternative to axillary lymph node dissection for staging, but its prognostic relevance is still uncertain. Detection of micrometastases in sentinel nodes and bone marrow may provide more information, but the clinical significance still needs to be confirmed by ongoing large trials. In this review, we focus on the possibility of sentinel lymph node biopsy or detection of bone marrow micrometastasis replacing traditional axillary lymph node dissection.

Intradermal radioisotope is superior to peritumoral blue dye or radioisotope in identifying breast cancer sentinel nodes

BACKGROUND

Sentinel lymph node (SLN) mapping and biopsy have emerged as the technique of choice for axillary staging of breast cancer. Several methods have been developed to identify SLNs, including peritumoral or intradermal injection of isosulfan blue dye or technetium sulfur colloid (TSC). We hypothesize that intradermal TSC is the optimal mapping technique and can be used alone to identify SLNs.

STUDY DESIGN

From March 1997 through January 2001, 180 women with T1 and T2 invasive breast cancer and clinically negative axilla underwent SLN mapping and biopsy. Peritumoral TSC was injected in 74 patients, 62 of whom also received peritumoral blue dye. Intradermal TSC (above tumor) was performed in 94 patients, 76 of whom also received peritumoral blue dye. Technetium-rich nodes were identified intraoperatively using a hand-held gamma probe and blue nodes were identified visually. Hematoxylin- and eosin-stained SLN sections were examined by light microscopy for breast cancer metastases.

RESULTS

Overall, the SLN mapping procedures were successful in 91% of patients. Peritumoral and intradermal TSC were successful in identifying SLNs in 78% and 97% of patients, respectively. Peritumorally injected isosulfan blue was successful in identifying 83% of SLNs. Intradermal TSC was found to be superior to peritumoral TSC and peritumoral blue dye in identifying SLNs (p = 0.00094, chi-squared, and p = 0.020, ANOVA).

CONCLUSIONS

SLN mapping by intradermal TSC has a significantly higher success rate than peritumoral TSC or blue dye. There was minimal benefit in identifying additional SLNs with addition of peritumoral blue dye to intradermal TSC. So, SLN mapping and biopsy using intradermal-injected TSC can be used alone to effectively stage the axilla for breast cancer.

Sentinel lymph node biopsy in patients with multifocal breast cancer

BACKGROUND

Multifocal or multicentric breast cancer has been suggested as a contraindication for sentinel node biopsy (SNB). However, recent studies have demonstrated that all quadrants of the breast drain through common afferent channels to a common axillary sentinel node. This should mean that the presence of multifocal tumour should not affect the lymphatic drainage. The purpose of this study was to evaluate the feasibility and accuracy of SNB in patients with multifocal breast cancer using a peritumoural injection technique for sentinel lymph node (SN) mapping.

METHODS

In the ALMANAC multicentre trial validation phase, we took SNB samples from 842 patients with node negative, invasive breast cancer with use of a blue dye and radiolabelled colloid mapping technique at the peritumoural injection site. All patients underwent standard axillary treatment after SNB. Seventy-five of the 842 patients had multifocal lesions on final histopathologic examination. The following analysis is focused on patients with multifocal lesions.

RESULTS

A mean number of 2.4 SNs were identified in 71 of 75 patients (identification rate: 94.7%). Thirty-one patients had a positive SN, 40 a negative SN. Standard axillary treatment confirmed the SN to be negative in 37 of 40 patients, whereas three patients revealed positive non-sentinel lymph nodes (false-negative rate: 8.8%). Overall SN biopsy accurately predicted axillary lymph node status in 68 of 71 patients (95.8%).

CONCLUSION

SNB accurately staged the axilla in multifocal breast cancer and may become an alternative to complete axillary lymph node dissection in node negative patients with multifocal breast cancer.

Internal Mammary Lymph Node (IMN) Coverage by Standard Radiation Tangent Fields in Patients Showing IMN Drainage on Lymphoscintigraphy

The purpose of this report is to evaluate the variability in coverage of the internal mammary nodal chain (IMN) by standard radiation tangential fields in those patients with medial drainage on lymphoscintigraphy. Twenty-two patients who showed lymphoscintigraphic IMN drainage underwent radiation simulation planned with computed tomography (CT). Standard tangent fields were placed and CT scans were reviewed to assess IMN inclusion and correlation with presternal fat thickness. Of the 22 patients who showed IMN drainage on lymphoscintigraphy, 10 (45%) had lateral primary lesions, 9 (41%) had medial lesions and 3 (14%) had subareolar lesions. Of these 22 women, 4 (19%) had the IMN completely within the standard tangent fields. Twelve women (55%) had only partial coverage of the IMN and the remaining 6 women (27%) had the IMN region completely outside. Presternal fat thickness greater than 10 mm was less likely associated with complete IMN coverage than fat thickness 10 mm or less, P = 0.001. Lymphoscintigram drainage to the IMN in breast cancer patients may suggest an increased risk of IMN involvement. Our data show that a majority (73%) of these patients had complete or partial incidental inclusion of the IMNs with standard tangents, which may in part explain the historically low IMN failure rate.

The Optimal Number of Sentinel Lymph Nodes for Focused Pathologic Examination

The sentinel lymph node (SLN) procedure provides an alternative method for assessing the axillary lymph nodes in patients with breast cancer. The SLN is typically subjected to a focused pathologic examination involving the examination of multiple tissue levels and/or keratin immunohistology. The number of SLNs submitted may vary widely, in some cases rivaling that of a complete axillary dissection (CAD). We examined our experience over the last 2 years in order to determine the optimal number of SLNs for focused pathologic evaluation. All SLN cases for the years 2000 and 2001 were retrieved from the files of the Pathology Department at Magee-Womens Hospital and were tabulated to determine the average number of SLNs per case, the number of SLNs submitted, the actual SLN that was positive for each case, the type of metastasis, and the average number of SLNs per case for each surgeon. There were 662 operative cases that yielded 1576 SLN accessions and 1758 total SLNs. The range of SLNs submitted was 1 to 11. Overall there was a mean of 2.4 SLNs accessioned per case and a mean of 2.7 SLNs per case. A study of the statistics of SLNs submitted by seven surgeons yielded two distinct groups, with one group submitting virtually all of the cases where there were consistently more than four SLNs per case. Ninety-seven percent of positive SLNs were discovered in the first three SLNs submitted, regardless of surgeon identity. The SLNs beyond numbers one to three yielded positive results by keratin in only four cases. Focused pathologic examination of SLNs was most effective for the first three SLNs submitted for any given case. The variation in the number of SLNs submitted per case was different based upon the different practice patterns of surgeons. It is suggested that for more than three SLNs submitted, simple routine lymph node examination would be appropriate.

Nuclear medicine and breast cancer: a review of current strategies and novel therapies

While breast cancer is still increasing in frequency, new diagnostic procedures are now available to challenge existing procedures and to make diagnosis of breast cancer more accurate and reliable. Mammography remains the standard investigation to reveal disease in an asymptomatic population: it can also be used to diagnose breast cancer in symptomatic patients (e.g. those with palpable breast lumps) and for guiding fine needle aspiration (FNA). Because the majority of breast lumps are benign, the challenge is to distinguish benign from malignant lesions without the use of invasive methods and this has attracted nuclear medicine physicians and medical oncologists to investigate the role of scintigraphic procedures to identify which patients require FNA. This review attempts to shed light on the various scintigraphic methods available which are of potential practical use in the assessment of malignant breast disease as well as looking at the possible role of nuclear medicine in the treatment of advanced disease.

Sentinel lymph node as a new marker for therapeutic planning in breast cancer patients

BACKGROUND AND OBJECTIVES

Literature review suggests that the sentinel lymph node (sN) represents a reliable predictor of axillary lymph node status in breast cancer patients; however, some important issues, such as the optimisation of the technique for the intraoperative identification of the sN, the role of intraoperative frozen section examination of the sN, and the clinical implications of sN metastasis as regards the surgical management of the axilla, still require further confirmation. The authors aimed (1) to assess the feasibility of sN identification with a combined approach (vital blue dye lymphatic mapping and radioguided surgery, RGS) and the specific contribution of either techniques to the detection of the sN, (2) to determine the accuracy and usefulness of intraoperative frozen section examination of the sN in order to perform a one-stage surgical procedure, and (3) to define how the sN might modulate the therapeutic planning in different stages of disease.

MATERIALS AND METHODS

From October 1997 to June 2001, 334 patients with early-stage (T(1-2) N(0) M(0)) invasive mammary carcinoma underwent sN biopsy; the average age of patients was 61.5 years (range, 39-75 years). In a subset of 153 patients, both vital blue dye (Patent Blue-V) lymphatic mapping and RGS were used to identify the sN, and the relative contribution of each of the two techniques was assessed.

RESULTS

In the whole group, the sN was identified in 326 of 334 patients (97.6%), and 105 of 326 patients (37.3%) had positive axillary lymph nodes (pN+). In 9 of 105 pN+ patients, the definitive histologic examination of the sN did not show metastases but these were detected in non-sN, thus giving an 8.6% false-negative rate, a negative predictive value of 94.5% (156/165), and an accuracy of 96.5% (252/261). As regards the specific contribution of the two different techniques used in the identification of the sN, the detection rate was 73.8% (113/153) with Patent Blue-V alone, 94.1% (144/153) with RGS alone, and 98.7% (151/153) with Patent Blue-V combined with RGS (P < 0.001). Noteworthy, whenever the sN was identified, the prediction of axillary lymph node status was remarkably similar (93-95% sensitivity; 100% specificity; 95-97% negative predictive value, and 97-98% accuracy) whichever of the three procedures was adopted (Patent Blue-V alone, RGS alone, or combined Patent Blue-V and RGS). Intraoperative frozen section examination was performed in 261 patients, who had at least one sN identified, out of 267 patients who underwent complete axillary dissection; 170 patients had histologically negative sN (i.o. sN-) and 91 patients histologically positive sN (i.o. sN+). All 91 i.o. sN+ were confirmed by definitive histology, whereas in 14 of 170 i.o. sN- patients (8.2%) metastases were detected at definitive histology. As regards the correlation between the size of sN metastasis, the primary tumour size, and the status of non-sN in the axilla, micrometastases were detected at final histology in 23 patients and macrometastases in 82 patients. When only micrometastases were detected, the sN was the exclusive site of nodal metastasis in 20 of 23 patients (86.9%) while in 3 patients with tumour size larger than 10 mm micrometastases were detected also in non-sN. Macrometastases were never detected in pT(1a) breast cancer patients; the sN was the exclusive site of these metastases in 30 patients (36.6%), while in 52 patients (63.4%) there were metastases both in sN and non-sN.

CONCLUSIONS

Sentinel lymphadenectomy can better be accomplished when both procedures (lymphatic mapping with vital blue dye and RGS) are used, because of the significantly higher sN detection rate, although the prediction of axillary lymph node status remains remarkably similar whichever method is used. The intraoperative frozen section examination proved to be rather accurate in predicting the actual pathologic status of the sN, with a negative predictive value of 91.8%; in 35% of patients it allowed sN biopsy and axillary dissection to be performed in a one-stage surgical procedure. Finally, specific clinical and histopathologic features of the primary tumour and sN might be used to tailor the loco-regional and systemic treatment in different clinical settings, such as in ductal carcinoma in-situ (DCIS), early-stage invasive breast cancer, and patients with large breast cancer undergoing neo-adjuvant CT for breast-saving surgery as well as elderly patients with operable breast cancer.

Sentinel node in the era of neoadjuvant therapy and locally advanced breast cancer

The most important determinant of prognosis for patients with breast cancer is the status of the axillary lymph nodes. Axillary lymph node dissection (ALND) has been performed for over a century to stage the cancer, achieve regional control, and perhaps improve survival. In accordance with tradition, ALND has been performed on all patients with the diagnosis of invasive breast cancer. In the early 1990s, this dogma was challenged because of the significant morbidity associated with ALND (paresthesia, extremity lymphedema) and the fact that greater than 50% of all breast cancers are node negative. A less morbid but highly accurate staging procedure, lymphatic mapping and sentinel lymph node biopsy (SNB) was introduced. Currently, the de facto standard of care in breast cancer is to perform LM and SNB in patients with small tumors and clinically negative axilla. While numerous methodological issues are being raised, the utility of LM and SNB identification continues to expand. In the current review we assess the application of this technique to locally advanced breast cancer (LABC) and neoadjuvant chemotherapy. What role does SNB play in locally advanced disease? Is LM and SNB accurate for patients with advanced disease? What influence do axillary metastases have on further treatment? What is the role of SNB in the planning for neoadjuvant patients? The skillful management of patients with breast cancer lies in the delicate balance between maximizing the efficacy of treatment and minimizing its morbidity and failure.

Emergence of sentinel node biopsy in breast cancer as standard-of-care in academic comprehensive cancer centers

BACKGROUND

Ongoing clinical trials are addressing the accuracy and safety of sentinel node biopsy (SNB) in the treatment of breast cancer; however, SNB is already increasingly being used in clinical practice. This study examined the extent and time trends of the use of SNB in stage I and II breast cancer patients.

METHODS

Clinical data were collected from stage I and II (tumor size < or =5.0 cm) breast cancer patients (n = 3003) who were treated at five comprehensive cancer centers between July 1, 1997, and December 31, 2000. Axillary surgery was classified as SNB alone, SNB + axillary node dissection (AND), AND alone, or none. Patterns of use of axillary surgery were summarized as the percentage of patients receiving each surgery type. The statistical significance of time trends for the use of SNB alone was analyzed by logistic regression models. All statistical tests were two-sided.

RESULTS

Overall, SNB alone was used in 13% of patients, SNB + AND in 22%, AND alone in 59%, and no axillary surgery in 6%. Use of SNB alone was statistically significantly associated with breast-conserving surgery of both smaller (< or =2 cm) and larger tumors (2-5 cm) (P<.001 for both associations). For stage I cancer patients treated with breast-conserving surgery (n = 1763), use of SNB increased statistically significantly over the study period, from 8% in 1997 to 9%, 14%, 15%, 22%, 42%, and 58% for the next six consecutive 6-month time intervals, respectively. After controlling for center, age, and comorbidity, the odds ratio for the use of SNB alone was 2.30 (95% confidence interval = 1.88 to 2.82) for each 6-month interval (P<.001).

CONCLUSIONS

Widespread use of SNB outside the clinical trial setting suggests that oncologists at cancer centers in our study have accepted SNB as standard-of-care for the treatment of breast cancer. This acceptance, if it occurs in other cancer centers and community practice, may affect accrual and generalizability of ongoing clinical trials of SNB.

The accuracy of sentinel lymph node biopsy in multicentric and multifocal invasive breast cancers

BACKGROUND

Sentinel lymph node biopsy (SLNB) has proved to be an accurate alternative to complete axillary lymph node dissection (ALND) in clinically node-negative breast cancer patients. Multicentric (MC) and multifocal (MF) invasive breast cancers are considered to be relative contraindications to SLNB. We examine the accuracy of SLNB in patients with MC and MF invasive breast cancers.

STUDY DESIGN

From September 1996 to August 2001, a total of 3,501 patients with clinically node-negative breast cancer underwent SLNB using both blue dye and radioisotope at our institution. A total of 70 patients had MC or MF invasive breast cancer, a successful SLNB, and mastectomy for local control. All had >/=10 axillary nodes excised (including the SLN) in a planned ALND. Exclusion criteria included MC and MF in situ carcinoma; breast conservation; previous breast irradiation, ALND, or SLNB; recurrent breast cancer; neoadjuvant chemotherapy; or ALND based solely on SLNB pathologic examination. RESULTS; The incidence of axillary metastases was 54% (38 of 70). SLNB accuracy was 96% (67 of 70), sensitivity 92% (35 of 38), and false-negative rate 8% (3 of 38). All patients with an inaccurate SLNB had a dominant invasive tumor >5 cm and one patient had palpable axillary disease intraoperatively. The SLN was the only site of axillary metastasis in 37% (14 of 38). Results were compared with those of published SLNB validation studies, most of which reflect experience with single-site invasive breast cancers. No statistically significant difference was noted for accuracy, sensitivity, or false-negative rate.

CONCLUSIONS

SLNB accuracy in MC and MF disease is comparable with that of published validation studies. MC and MF patients with a dominant T3 tumor (>5 cm) or axillary disease palpable intraoperatively should have a concurrent formal ALND. Our retrospective data suggest SLNB may be used as a reliable alternative to conventional ALND in selected patients with MC or MF disease. Further studies in this patient population are warranted.

Sentinel lymph nodes with technetium-99m colloidal rhenium sulfide in patients with esophageal carcinoma

BACKGROUND

The authors assessed the detection of sentinel lymph nodes in patients with esophageal squamous cell carcinoma (SCC) using technetium-99m colloidal rhenium sulfide. They studied whether an analysis of sentinel lymph nodes using cytokeratin (CK) immunohistochemistry increased the accuracy of staging.

METHODS

The authors observed 25 patients with thoracic esophageal carcinomas who underwent radical esophagectomy. The day before surgery, technetium-99m colloidal rhenium sulfide was injected into the submucosa at four sites around the primary tumor. Lymphoscintigraphy was performed. Esophagectomy and regional lymph node dissection were performed 17 hours after the technetium-99m injection. After surgery, the resected lymph nodes were evaluated by CK staining.

RESULTS

Lymphoscintigraphy detected sentinel lymph nodes in 92% of the patients (23 of 25 patients). The accuracy of sentinel lymph node was 91.3% (21 of 23 patients), the sensitivity was 86.7% (13 of 15 patients), and the false-negative rate was 8.7% (2 of 23 patients). A comparison of the number of sentinel lymph nodes and clinicopathologic factors showed that there was a significant association between the number of sentinel lymph nodes and lymph node status (P < 0.01), pathologic stage (P < 0.05), and the number of metastatic lymph nodes (P < 0.05). Occult metastasis was detected by CK staining in 14 (56%) of the 25 patients and in 23 (1.7%) of 1406 lymph nodes. Because the 2 false-negative (sentinel lymph node-negative and nonsentinel lymph node-positive) patients who had occult metastases in the sentinel lymph nodes, the accuracy of sentinel lymph node evaluation using CK staining was 100% (23 of 23).

CONCLUSIONS

Lymphatic mapping with technetium-99m colloidal rhenium sulfide was used to identify the lymphatic basin and was feasible in patients with esophageal SCC. An analysis of sentinel lymph nodes using CK immunohistochemistry increased the accuracy of sentinel lymph node.

Mammographic and clinical predictors of drainage patterns in breast lymphoscintigrams obtained during sentinel node procedures

PURPOSE

The authors' purpose was to explore the association between mammographic findings and drainage patterns on lymphoscintigrams obtained during sentinel node procedures for breast carcinoma.

MATERIALS AND METHODS

From July 1997 to March 2000, 132 patients with breast cancer who were included in a prospective mammography-pathology correlation and staging database were imaged 2 hours after perilesional injection of 1 mCi filtered (0. 22 microm) Tc-99m sulfur colloid (4 ml volume) before sentinel node procedures.

RESULTS

Sixty-four percent of the scans showed axillary drainage only, 9% showed axillary and internal mammary drainage, and 4% revealed internal mammary drainage only. Twenty-three percent of scans showed no drainage. Of the patients who showed drainage, 17% showed drainage to the internal mammary basin, and 5% showed this exclusively. Internal mammary drainage was seen in 18% (10 of 57) of lateral, 21% (6 of 29) of medial, and 14% (1 of 7) of subareolar lesions (P = NS). No drainage was seen in 22% of patients with predominantly fatty mammographic parenchymal density (>50%) compared with only 8% of patients with predominantly dense (>50%) parenchyma (P < 0.05). Failure to show drainage was more common in women older than 50 years (P < 0.05). Axillary sentinel nodes were identified surgically in 73% of patients with negative scan findings. There was no significant association between scintigraphic drainage and mammographic soft tissue tumor size and appearance, histologic findings, or axillary node status.

CONCLUSIONS

Dense mammographic parenchyma and age less than 50 years are associated with identification of lymphatic drainage on lymphoscintigrams performed before sentinel node procedures in 91% to 92% of patients. Internal mammary drainage, present in 18% of lateral and 21% of medial lesions, may direct therapy to include internal mammary lymph nodes.

Evaluation of immunohistochemistry and multiple-level sectioning in sentinel lymph nodes from patients with breast cancer

CONTEXT

Previous investigations on sentinel lymph node biopsies have demonstrated their importance in nodal staging of patients with breast cancer. However, sentinel node biopsy in breast cancer is currently a controversial procedure and continues to provoke debate.

OBJECTIVES

We designed our study to determine the usefulness of a standard protocol for evaluating sentinel lymph node metastases and to assess the value of sentinel node biopsy as the only procedure in nodal staging in breast cancer patients.

MATERIALS AND METHODS

A retrospective analysis of 84 breast cancer patients with sentinel node biopsies, who also underwent axillary dissection, was conducted using a standard protocol (3 levels of immunohistochemical stains for keratin and 2 levels of hematoxylin-eosin (HE) stains on the first 3 negative lymph nodes).

RESULTS

Hematoxylin-eosin staining identified 20 patients (23.8%) with sentinel node metastases. The remaining 64 negative patients (76.1%) were tumor free on sentinel lymph nodes at level 1 HE. Additional immunohistochemical stains for keratin and HE stains on specimens from these 64 patients showed an additional 5 patients (7.8%) to be positive for lymph node micrometastases (<2 mm). The total percentage of cases with sentinel lymph node metastases detected by HE staining and immunohistochemistry was 29.7%. Of the remaining 59 cases that were negative on HE and immunohistochemistry, axillary dissection revealed 3 cases that had metastases in the axillary lymph nodes. The false-negative rate was 10.7%. The concordance rate between sentinel lymph nodes and axillary lymph nodes was 96.4%. The sensitivity was 89% and specificity was 100%.

CONCLUSION

Immunohistochemistry and multiple-level sectioning increased detection of metastases by 7.8% in sentinel lymph nodes. Caution should be used in accepting sentinel node biopsy alone as the only procedure for staging due to a high false-negative rate (10.7%). A predictive value of 96.4% confirms that sentinel lymph node biopsy is most likely to contain metastatic carcinoma. Sentinel lymph node examination with the protocol we describe, combined with axillary dissection, increased the yield of metastatic disease by identifying 8 additional cases of nodal metastatic disease (an increase of 28%), as compared to standard axillary nodal dissection and single-section sentinel lymph node examination alone.

Clinicopathologic factors predicting involvement of nonsentinel axillary nodes in women with breast cancer

BACKGROUND

It is unclear which breast cancer patients with positive sentinel lymph nodes (SLNs) require a completion axillary lymph node dissection. Our aim was to determine factors that predict involvement of nonsentinel axillary nodes (NSLNs) in patients with positive SLNs.

METHODS

We reviewed the records of all patients with invasive breast cancer who underwent SLN biopsy at our institution between 1993 and August 2001. Multivariate analysis was used to identify clinicopathologic features in SLN-positive patients that predict involvement of NSLNs.

RESULTS

A total of 131 patients had a positive SLN and underwent completion axillary lymph node dissection. Multivariate analysis revealed that primary tumor >2 cm (P =.009), SLN metastasis >2 mm (P =.024), and lymphovascular invasion (P =.028) were independent predictors of positive NSLNs. The number of SLNs harvested was a significant negative predictor (P =.04). In our model, based on the presence of these factors, the positive predictive value was 100% for a score of 4.

CONCLUSIONS

The likelihood of positive NSLNs correlates with primary tumor size, size of the largest SLN metastasis, and presence of lymphovascular invasion. A scoring system incorporating these factors may help determine which patients would benefit from additional axillary surgery.

Technical Limitations of Sentinel Node Biopsy in Breast Cancer: A Single Surgeon's Experience

Few studies have attempted to critically identify patient- and tumor-related factors that limit sentinel node biopsy (SNB). These studies have been limited by sample size and surgeon variability. The present study attempts to enumerate these limitations in a unique group of patients. One hundred twenty-five SNBs performed by a single surgeon between May 1997 and June 2001 were reviewed. Overall SNB was successful in 96 per cent of patients with a 97 per cent correlation with the axillary node dissection. Sentinel node identification was not affected by age, tumor size, tumor location, prior segmental resection, or neoadjuvant therapy. No false negatives were noted in the neoadjuvant group. The use of blue dye alone significantly understaged patients when compared with isotope alone ( P = 0.02). SNB is a highly accurate method to identify axillary metastases and its limitations are not affected by patient or tumor related factors. In the present study SNB detection by both isotope and blue dye has been shown to be superior to blue dye alone. This finding demonstrates that these limitations may be overcome with the standardization of the technique used.

Sentinel node biopsy with technetium-99m colloidal rhenium sulphide in patients with breast cancer

Background

Sentinel node biopsy is emerging as a technique to replace routine axillary lymph node dissection. The lymphatic mapping technique is still at a developmental stage and no standard technique exists. This study used technetium-99m colloidal rhenium sulphide with a mean particle size of 100 (range 50–200) nm for sentinel node mapping.

Methods

Eighty-seven patients with breast cancer, but no clinical evidence of axillary metastasis, were studied. One day before operation technetium-99m colloidal rhenium sulphide was injected at four points into breast tissue surrounding the tumour. Lymphoscintigraphy was performed 2 h after injection, and surgery was usually performed after 20 h. A hand-held γ probe guided sentinel node biopsy.

Results

Lymphoscintigraphy revealed axillary hot spots in all patients. During operation, the sentinel node was identified in all 87 patients (100 per cent). The number of sentinel nodes per patient ranged from 1 to 5 (mean 2). Metastatic sentinel nodes were identified in 37 of 87 patients. There were no false negatives.

Conclusion

This study suggests that technetium-99m rhenium sulphide is a suitable agent for sentinel node mapping in patients with breast cancer.

Will we need lymph node dissection at all in the future?

Traditionally in the treatment of primary breast cancer, axillary lymph node dissection (ALND) plays an important role. However, a substantial and increasing percentage of patients appear to have no nodal involvement and have been subjected to ALND unnecessarily. The first reason to perform an ALND is axillary nodal staging. After reviewing the literature, it can be concluded that in clinically node-negative patients an adequately conducted lymphatic mapping by sentinel node procedure is equal to ALND for this purpose. The second reason to perform an ALND is to establish the extent of nodal involvement, which might have an impact on adjuvant treatment recommendations. However, there is no evidence available that patients with extensive nodal involvement (= 4 positive nodes) benefit more from adjuvant systemic treatment (either standard or high dose) in terms of reduction of odds of recurrence and mortality compared to patients with limited nodal involvement and optimally administered so-called standard adjuvant treatment. The third reason to perform an ALND is to ensure axillary tumor control. Reviewing the different treatment options, it can be concluded that in clinically node-negative patients axillary control after axillary radiotherapy appears to be similar to axillary control after ALND. In clinically overt axillary involvement, ALND (with or without adjuvant radiotherapy) may result in an improved regional control. In the near future, ALND will not be the standard of care but will be reserved for those patients with proven axillary lymph node involvement. In microscopic disease, radiotherapy may be an alternative with equal control and less morbidity.