Biology of lymphatic metastases in breast cancer: lessons learned from sentinel node biopsy

Sentinel lymph node biopsy for breast cancer: from investigational procedure to standard practice

Sentinel lymph node biopsy, popularized in melanoma, has revolutionized the management of breast cancer. While the morbidity associated with axillary node dissection was once thought to be a requisite risk in order to appropriately stage the axilla, large validation studies have demonstrated that sentinel lymph node biopsy is a minimally invasive technique that can accurately predict nodal status. This technique has become an accepted practice in many centers, but there remain many controversies surrounding the technique itself, the pathologic evaluation of the sentinel node and the optimal management of patients with minimal nodal disease. The historic roots of this technique are discussed, along with the controversial issues surrounding the technique and the clinical trials that are currently ongoing.

Breast cancer sentinel lymph node mapping using near-infrared guided indocyanine green in comparison with blue dye

Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) was considered to have the potential to improve sentinel lymph node (SLN) mapping in breast cancer. Herein, we performed a randomized clinical trial to evaluate the effectiveness of ICG fluorescence imaging compared with blue dye imaging in SLN navigation surgery. We also analyzed lymph drainage pathways to identify targets for sentinel lymph node biopsy (SLNB). Finally, 68 consecutive patients diagnosed with breast cancer and who underwent SLNB between November 2010 and September 2012 were enrolled in the study. The cases were randomly grouped into either the ICG fluorescence or blue dye group, with 36 in the ICG fluorescence group and 32 in the blue dye group. Levels I and II axillary dissection was performed in all cases after SLNB. A single lymph drainage pathway was detected in 21 of 36 (58.3%) patients, and multiple lymph drainage pathways were detected in 15 of 36 (41.7%) cases. The detection rate of SLNB was higher by ICG fluorescence than by blue dye (97.2 vs. 81.3%, p < 0.05), as 3.6 SLNs were detected on average in the ICG fluorescence group compared to 2.1 in the blue dye group. However, the sensitivity and false-negative rate were similar in the two groups. In conclusion, ICG fluorescence was superior to blue dye for the identification of the SLN.

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.

Sentinel lymph node biopsy for breast cancer patients using fluorescence navigation with indocyanine green

BACKGROUND

There are various methods for detecting sentinel lymph nodes in breast cancer. Sentinel lymph node biopsy (SLNB) using a vital dye is a convenient and safe, intraoperatively preparative method to assess lymph node status. However, the disadvantage of the dye method is that the success rate of sentinel lymph node detection depend on the surgeon's skills and preoperative mapping of the sentinel lymph node is not feasible. Currently, a vital dye, radioisotope, or a combination of both is used to detect sentinel nodes. Many surgeons have reported successful results using either method. In this study we have analyzed breast lymphatic drainage pathways using indocyanine green (ICG) fluorescence imaging.

METHODS

We examined the lymphatic courses, or lymphatic vessels, in the breast using ICG fluorescence imaging, and applied this method to SLNB in patients who underwent their first operative treatment for breast cancer between May 2006 and April 2008. Fluorescence images were obtained using a charge coupled device camera with a cut filter used as a detector, and light emitting diodes at 760 nm as a light source. When ICG was injected into the subareola and periareola, subcutaneous lymphatic vessels from the areola to the axilla became visible by fluorescence within a few minutes. The sentinel lymph node was then dissected with the help of fluorescence imaging navigation.

RESULTS

The detection rate of sentinel nodes was 100%. 0 to 4 states of lymphatic drainage pathways from the areola were observed. The number of sentinel nodes was 3.41 on average.

CONCLUSIONS

This method using indocyanine green (ICG) fluorescence imaging may possibly improve the detection rate of sentinel lymph nodes with high sensitivity and compensates for the deficiencies of other methods. The ICG fluorescence imaging technique enables observation of breast lymph vessels running in multiple directions and easily and accurately identification of sentinel lymph nodes. Thus, this technique can be considered useful.

[Axillary recurrences after sentinel lymph node biopsy in initial breast cancer]

OBJECTIVE

The aim of our study was to analyze the application of the Selective Sentinel Lymph Node Biopsy (SLNB) in early Breast Cancer of our population, through the analysis of axillary recurrences in patients with false negative sentinel node procedures without complete axillary lymphadenectomy, after a subsequent clinical follow-up.

MATERIAL AND METHODS

A total of 218 early Breast Cancer patients who underwent SLNB after being diagnosed of early breast cancer (T1-2N0) with complete axillary dissection only when the SLNB was positive in the histopathological analysis. In every case, a 2-day protocol was used to localize the sentinel node after injection of (⁹⁹m)Tc-Nanocolloid.

RESULTS

The mean subsequent clinical follow-up was 27 months. A total of 413 sentinel nodes were removed with a median of 1.89/p (range 1-5). Infiltration was detected in 33.9% of patients (59.45% macrometastasis, 22.97% micrometastasis and 17.5% Isolated Tumor Cells (ITC)) and negative for the other nodes excised after conventional lymphadenectomy in 60% of cases. In our population, there was only one case of false negative (FN) SLN due to massive lymphatic blockage, and an abnormal lymph node without uptake adjacent to the SLN was identified intraoperatively. No case of axillary recurrence was detected during an average follow-up of 27 months.

CONCLUSION

The absence of axillary recurrences in our population with negative SLNB without complete axillary dissection demonstrates the appropriate local control offered by this procedure in early Breast Cancer.

[Sentinel node in breast cancer. Experience of the Salah-Azaïz Institute of Tunis]

INTRODUCTION

Breast cancer screening increased the ratio of small tumours. These tumours have a low lymph node metastatic potential. Sentinel node detection allows detecting axillary lymph node invasion without the morbidity of complete axillary lymph node dissection.

OBJECTIVES

In this study we report the results of the learning curve of sentinel node detection in the Institut Salah-Azaïz of Tunis.

MATERIALS AND METHODS

It is a prospective study between January 2004 and December 2005 in which 115 patients were included with breast cancer less than 3 cm without antecedents of breast surgery. All these women had sentinel node dissection by a colorimetric method and 30% had a combined method (colorimetric and isotopic).

RESULTS

The rate of detection was 97.3% (n = 112). An extemporaneous examination was performed in 91 patients. The rate of negative forgery of the extemporaneous examination was 4.3% and the sensitivity of 95.7%. There are no false positive with the extemporaneous exam. The sentinel lymph node was the only node invaded in 15 patients (44%). In 3 patients, the sentinel node was healthy whereas the axillary dissection was positive, so the false negative rate is about 2.6%.

CONCLUSION

Sentinel node dissection is a reliable and feasible technique. It however requires a training of the surgeon, the pathologist and the nuclear doctor. It allows to reduce the morbidity of the treatment of the breast cancer by avoiding "useless" axillary dissection out in patients without node invasion. The increase in the number of the small cancers discovered during screening makes it possible to increase the number of patients who can profit from this technique.

What is a sentinel node? Re-evaluating the 10% rule for sentinel lymph node biopsy in melanoma

INTRODUCTION

Many surgeons use the "10% rule" to define whether a lymph node is a sentinel node (SLN) when staging malignant melanoma. However, this increases the number of SLN removed and the time and cost of the procedure. We examined the impact of raising this threshold on the accuracy of the procedure.

METHODS

We reviewed the records of 561 patients with melanoma (624 basins) who underwent SLN with technetium Tc99 labeled sulfur colloid using a definition of a SLN as 10% of that of the node with the highest counts per minute (CPM).

RESULTS

Of the 624 basins, 154 (25%) were positive for metastases. An average of 1.9 nodes per basin were removed (range 1-6). Metastases were found in the hottest node in 137 cases (89% of positive basins, 97% of basins overall). Increasing the threshold above 10% decreased the number of nodes excised and the costs involved, but incrementally raised the number of false negative cases above baseline (a 4% increase for a "20% rule," 5% for a "30% rule," 6% for a "40% rule," and 7% for a "50% rule"). Taking only the hottest node would raise the false negative rate by 11%.

CONCLUSIONS

Although using thresholds higher than 10% for the definition of a SLN will minimize the extent of surgery and decrease the costs associated with the procedure, it will compromise the accuracy of the procedure and is not recommended.

Added value of the presence of blue nodes or hot nodes in sentinel lymph node biopsy of breast cancer

BACKGROUND

Combined use of blue dye and radiocolloid is considered to be useful for sentinel lymph node (SLN) biopsy of breast cancer. Whether both techniques together is superior to either alone was analyzed.

PATIENTS AND METHODS

A consecutive series of 308 cases of breast cancer who underwent SLN biopsy using the combination technique was used. The frequency of a blue node or hot node was analyzed in all cases and only node-positive cases. Furthermore, the frequency of a blue node and hot node together, or either alone, and the highest radiocount of the SLNs in each case were examined for correlation with 8 clinicopathologic features. Three types of SLN containing both blue dye and radioactivity (blue-hot node), blue dye alone (blue-only node) and radioactivity alone (hot-only node), and the SLN radiocounts were analyzed for correlation with metastatic tumor.

RESULTS

Of 308 cases, a blue node was present in 298 (97%), a hot node in 295 (96%), and either a blue or hot node in 306 (99%). The presence of a blue node or hot node was similarly affected by previous surgical biopsy and body mass index (BMI), and the presence of a hot node was also affected by age and tumor location. However, the presence of either a blue node or hot node was not affected by any of these characteristics. Of 77 node-positive cases, 8 (10%), 15 (19%) and 6 (8%) were considered to be node-negative based on blue node, hot node and either blue node or hot node positivity, respectively. The frequency of positivity for SLN metastasis decreased in order from blue-hot, blue-only to hot-only nodes. Of 62 cases with metastatic hot nodes, six (10%) were negative when the hottest node was examined, but the second-hottest node was positive.

CONCLUSIONS

The added value of the presence of blue node or hot node was confirmed in the SLN biopsy using the combination technique, which suggests that all blue nodes and hot nodes need to be harvested.

Double mapping with subareolar blue dye and peritumoral green dye injections decreases the false-negative rate of dye-only sentinel node biopsy for early breast cancer: 2-site injection is more accurate than 1-site injection

BACKGROUND

The optimum sentinel node biopsy (SNB) mapping method for breast cancer remains to be determined. No matter which mapping agents are used, 2-site injection may be superior to 1-site injection in limiting the false-negative rate.

METHODS

We examined whether a double-mapping method with subareolar injection of blue dye and peritumoral injection of green dye would decrease the false-negative rate of dye-only SNB in 145 patients with early breast cancer.

RESULTS

The identification rate for blue-dyed and/or green-dyed (including mixed color-dyed) lymph nodes was 96.6% (140/145). Sensitivity and specificity were 95.1% (39/41) and 100% (99 of 99), respectively. Accuracy was 98.6% (138/140) with a false-negative rate of 4.9% (2/41). There were 4 patients in whom nodes of each color were found, but nodes of only 1 color were shown to be positive. The primary tumors of these 4 patients and of the 2 patients with false-negative results were located in the upper-outer quadrant of the breast. When only blue-dyed or green-dyed nodes (including mixed color-dyed nodes) were counted, the false-negative rates were 10.3% (4/39) for the subareolar mapping technique and 10.0% (4/40) for the peritumoral mapping technique.

CONCLUSIONS

The double-mapping method based on subareolar and peritumoral injections decreases the false-negative rate of dye-only SNB for early breast cancer. Variations in lymphatic channels may exist in the lateral half of the breast and thus may influence identification of positive sentinel nodes. This finding should be taken into account in cases of multicentric breast cancer.

The influence of radioisotope vehicle on breast sentinel node detection

AIM

To assess the relationship between carrier molecule size and time elapsing between marker injection and sentinel node(s) biopsy in patients with breast cancer.

MATERIAL

The study performed on 122 women, in whom the sentinel node(s) was identified according to the procedure described below. In Group I (n=72 patients), SN identification was done with radioisotope marker of 400-3000 nm molecule size (tin colloid). In Group II (n=50 patients) radioisotope marker of <100 nm molecule size (colloidal albumin) was used.

METHODS

All the patients of both groups received the markers with a single-point, intradermal, periareolar injection. Four hours after the injection (Group I - surgery in the next day) or immediately before the surgery (in this same day) (Group II), stationary lymphoscintigraphy was performed.

RESULTS

Mean numbers of sentinel nodes identified with the radioisotope method in Groups I and II were 1.22 and 1.48, respectively. The difference was statistically significant (p<0.01).

CONCLUSIONS

There is a relationship between the radioisotope marker molecule size and the injection-to-intra-operative evaluation time. Administration of small molecule size radioisotope marker several hours prior to the planned surgery appears to be the optimum procedure in this method of SN identification in patients with breast cancer.

The number distribution for involved lymph nodes in cancer

The number of involved lymph nodes exhibits considerable heterogeneity within populations. Here, the implications of population heterogeneity are explored with respect to the kinematics of nodal metastases. Data from the National Cancer Institute's Surveillance, Epidemiology, and End Results program for 224656 breast, 12404 gastric, 18015 rectal, 4117 cervical and 2443 laryngeal cancers as well as 9118 melanomas were used to construct frequency distributions for the number of involved nodes which were then fitted to the negative binomial distribution. The negative binomial distribution described the heterogeneity in nodal involvement well. The patterns of nodal involvement can be explained by either of two models: one where involved nodes could seed further nodal metastases, the other where the number of nodal metastases in any individual was randomly distributed, with the deviations between patients accounted for by population heterogeneity. Since the number of sampled nodes similarly approximated a negative binomial distribution, random involvement with superimposed population heterogeneity would more credibly explain both sets of observations.

Accuracy and reliability of sentinel node biopsy in patients with breast cancer. Single centre study with long term follow-up

The aim of our study is to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer. A total of 791 breast cancer patients underwent sentinel lymph node (SLN) biopsy at our institution between July 1997 and February 2005. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (50 patients) and the application phase (741 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied postoperatively with breast cancer and lymphadenectomy was performed when considered warranted by the pathological postoperative results. The median follow-up duration in the 741 patients studied during the application phase was 32.3 months (range 6-72 months). In this phase a total of 787 sentinel nodes (719 axillary and 68 intramammary chain) were obtained (range 0-5 per patient, mean 1.01), with 153 (41 with micrometastasis) positive sentinel nodes. We observed a total of three FN SLN results (0.5%). All three presented as an axillary recurrence into 24 months from operation. After a median follow-up of 32.3 months we observed only three clinical recurrences among 741 patients. Our results indicate that the sentinel node protocol can give an adequate local control.

Should sentinel lymph-node biopsy be used routinely for staging melanoma and breast cancers?

The sentinel lymph node (SLN) is the lymph node that represents the 'gate-keeper' of the lymphatic basin; it is the first node to receive lymphatic drainage from the site of the primary tumor. SLN biopsy is a staging procedure and should be considered as such; it is not meant to be a therapeutic operation. The SLN can be mapped and biopsied using tracer agents (e.g. radiolabelled colloid and/or vital blue dye), which are injected around the primary tumor site. Pathologic analysis of the SLN using a combination of serial sectioning of the node, standard hematoxylin and eosin staining, and immunohistochemistry decreases the false-negative rate compared with traditional nodal processing. SLN biopsy is associated with lower morbidity than full lymphadenectomy. The SLN technique accurately reflects the metastatic status of the regional lymph-node basin; recurrent nodal disease in the mapped basin is rare following a tumor-free SLN biopsy result. The objectives of this review are to provide a current and concise overview of the current literature on SLN biopsy and describe its role in clinical oncology.

Statistical kinematics of axillary nodal metastases in breast carcinoma

The number of involved lymph nodes in individuals with breast cancer is highly variable, and of both prognostic and therapeutic importance. A statistical description for the frequency distribution of the numbers of involved nodes in an affected population could potentially reveal mechanisms of axillary metastasis, and eventually facilitate predictive models for tumor control and axillary sampling. A meta-analysis of 15 studies involving 24,757 axillary dissections was performed, including conventional dissections, sentinel node dissections and studies of occult metastases. Frequency histograms for the numbers of involved axillary lymph nodes from the populations were tested for clustering and they were fitted, as a first approximation, to a negative binomial distribution. Although the number of involved nodes per individual was quite variable, some individuals sustained more involved nodes than could be expected from a random (Poisson) distribution. The negative binomial distribution, however, provided acceptable descriptions for the distributions of involved nodes in all populations studied. Two mechanisms could explain these observations: (1) an apparent contagion model, where involved nodes seeded further nodal metastases, and (2) a spurious contagion model where the number of involved nodes per individual was randomly (Poisson) distributed and population heterogeneity accounted for the more severe cases. Both models were consistent with the hypothesis that the nodal metastasis is a chance event, with the probability of involvement greatest for nodes contiguous to the primary tumor and proportioned by lymphatic flow.

Clinical axillary recurrence after sentinel node biopsy in breast cancer: a follow-up study of 220 patients

PURPOSE

The aim of this study was to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer and the subsequent clinical outcome in such patients.

METHODS

A total of 325 breast cancer patients underwent sentinel lymph node biopsy at our institution between June 1998 and May 2004. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (105 patients) and the application phase (220 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied intraoperatively and lymphadenectomy was performed when considered warranted by the pathological intraoperative results.

RESULTS

The median follow-up duration in the 220 patients studied during the application phase was 21.2 months (range 4-45 months). In this phase a total of 427 sentinel nodes were obtained (range 1-5 per patient, median 1.99), with 66 positive sentinel nodes in 56 patients (26%). The lymphadenectomies performed were also positive in 25% of cases (14 patients). We observed a total of two false-negative sentinel lymph node results (3.45%). One of them was found during the surgical excision of non-sentinel nodes, and the other presented as an axillary recurrence 17 months postoperatively (1.72% clinical false-negative rate). The latter patient died 1 year after the first recurrence.

CONCLUSION

After a median follow-up of 21.2 months we observed only one clinical recurrence among 220 patients. Our results indicate that adequate local control is achieved by application of the sentinel node protocol.

Lymphatic mapping and sentinel lymphadenectomy for breast cancer

Lymphatic mapping and sentinel lymphadenectomy has become an important tool for axillary lymph node staging in women with early-stage breast cancer. This review examines data regarding the staging accuracy, indications and technical aspects of the procedure, and clinical trials investigating the technique. Multiple studies now confirm that sentinel lymphadenectomy accurately stages the axilla and is associated with less morbidity than axillary dissection. Blue dye, radiocolloid, or both can be used to identify the sentinel node, and several injection techniques may be used successfully. Many patient factors previously thought to affect accuracy of the procedure have now been shown to be of limited significance. The indications for the procedure are expanding, and the histopathologic evaluation of the sentinel node and the role of lymphoscintigraphy have been clarified. Clinical trials are now underway that will determine the prognostic significance of micrometastases and the therapeutic benefit of axillary dissection in women with and without sentinel node metastases. Incorporation of sentinel lymphadenectomy into routine clinical practice will maintain accurate axillary staging with lower morbidity and improved quality of life for women with early-stage breast cancer.

Influence of the New AJCC Breast Cancer Staging System on Sentinel Lymph Node Positivity and False-Negative Rates

The sixth and newest edition of the American Joint Committee on Cancer (AJCC) staging system for breast cancer now defines axillary sentinel lymph nodes with micrometastatic deposits 0.2 mm in diameter or smaller as node-negative. The aim of this study was to determine how this new classification scheme would affect axillary sentinel lymph node positivity, false-negative rate, and overall accuracy of an inception cohort of 205 breast cancer patients undergoing definitive surgery that included sentinel lymph node biopsy plus level I/II axillary lymphadenectomy. Based on the previous AJCC system for staging breast cancer, in which all sentinel lymph node metastases were considered positive, the rate of nodal positivity in this cohort was 47%, the overall accuracy was 99%, and the false-negative rate was 2.1%. According to the new classification system, the rate of nodal positivity in this cohort was 39.5% and the overall accuracy was 98%. The false-negative rate rose to 4.9% because two patients with micrometastatic deposits 0.2 mm or smaller, which are considered node-negative in the new system, had macroscopically positive disease in non-sentinel lymph nodes found in the completion lymphadenectomy.

Seroma prevention following axillary dissection in patients with breast cancer by using ultrasound scissors: a prospective clinical study

AIMS

Seroma formation following axillary dissection is a common complication of breast surgery. The aims of this study were (1) to analyse the risk factors of seroma formation, and (2) to evaluate the role of ultrasound scissors in performing axillary dissection in patients with primary breast cancer undergoing mastectomy and breast-conserving surgery.

METHODS

Ninety-two women (median age 55 years, range 33-73 years) requiring surgery for known unilateral primary breast cancer (pT1a=1, pT1b=20, pT1c=43, pT2=25, pT3=3) were prospectively randomised to undergo axillary dissection by either using (Group A, 45 patients) or not using (Group B, 47 patients) ultrasound scissors (US). Thirty-eight (41.3%) patients underwent modified radical mastectomy, while 54 (58.7%) underwent breast-conserving surgery.

RESULTS

Twenty-eight (30.4%) patients (Group A=9 out of 45, 20%; Group B=19 out of 47, 42%; P=NS) developed a wound seroma. Multivariate analysis using a logistic regression model showed that surgical procedure (RR=8.9; 95% CI: 3.2-25.3), total amount of drainage (RR=7.8; 95% CI: 2.8-22.0), and size of the tumour (RR=6.0; 95% CI: 2.2-16.5) independently correlated with seroma formation. The logistic regression function (RR=19.4; 95% CI: 6-62) correctly allocated 75 out of 92 (81.5%) patients.

CONCLUSIONS

Size of the tumour, and total amount of drainage represent the principal factors of seroma formation following axillary dissection in patients undergoing surgery for breast cancer. Although the use of ultrasound cutting devices may reduce the risk of seroma formation, further studies are need to verify the real impact on long-term morbidity of such technique.

Sentinel node biopsy in breast cancer and melanoma requires adequate self‐audit

BACKGROUND

Sentinel node biopsy (SNB) is an evolving technique with potential for improving staging. Melanoma and breast cancer are the two most commonly used applications. The present study relates the author's validation data in both diseases.

METHODS

Review of a prospective database.

RESULTS

Between January 2000 and December 2001 92 cases of breast cancer were offered SNB. The first 48 had completion axillary dissection. The identification rate was 92%. There were 28 true negative, 15 true positive and one false negative case. A mean of 2.0 nodes were removed (range 1-4). Completion axillary dissection removed a mean of 15.1 nodes. The following 44 cases were offered a choice of SNB alone, axillary dissection or a combination of techniques. Thirty-seven women chose SNB alone. There was one technical failure, 28 negative SNB and eight positive SNB results. A mean of 3.1 lymph nodes were removed (range 1-9) applying a 10% rule. At 24-36 months follow up there have been no cases of locoregional recurrence. From January to December 2001 36 cases of melanoma > or =1 mm were managed with SNB. Twenty-eight SNB were negative and eight were positive (22%). At follow up (range 12-24 months) there were three locoregional recurrences, but only one of these were in the node basin determined to be previously negative by SNB (3.5%).

DISCUSSION

Sentinel node biopsy in breast cancer is a valid alternative to full axillary dissection for staging the axilla. Patients can make an informed choice to have SNB alone if they understand the limitations of the technique and possible consequences of these limitations. In melanoma SNB provides valuable prognostic information most melanoma patients prefer to have. Adequate self-audit is necessary before a patient can make an informed decision to have SNB in either disease.

Localización del ganglio centinela en cáncer de mama. Inyección periareolar del radiocoloide

Traditional lymphadenectomy is being replaced by sentinel node biopsy in initial management of early stage breast cancer. The aim of this study was to validate the technique in our center, where we perform preoperative lymphoscintigraphy and intraoperative detection of sentinel node, after periareolar radiotracer and peritumoral blue dye injection. Sixty patients, breast cancer stages I and II, were included. Lymphatic mapping was performed the day before surgery, after the administration of 74 MBq 99mTc sulfur colloid in periareolar subdermal tissue. Surgical detection of sentinel node through gamma probe was followed by intraoperative and occasionally delayed biopsies. Finally, full axillary node dissection was completed. Lymphoscintigraphy identified sentinel node in 78% of the patients (47/60): 43 in axilla, 4 in internal mammary chain. Probe guided axillary detection was achieved in 88% (53/60): in every patient with axillar migration in scan, in 9/13 without imaged drainage and in 1/4 with internal mammary chain migration. Sensitivity of blue dye technique was 75% (45/60), the concordance between both procedures being high. Considering both, the overall success rate of surgical detection was 90% (54/60); if we exclude those patients who showed exclusive extraaxillar drainage, the success rate reaches 95%. Malignancy was found in 24% of sentinel nodes removed (13/54); it being the only metastatic axillary node in 4/13. No false negative sentinel nodes were found. Therefore, negative predictive value and accuracy were 100%. These results allow us to validate the technique in our center.

Usefulness of Ultrasound Scissors in Reducing Serous Drainage after Axillary Dissection for Breast Cancer: A Prospective Randomized Clinical Study

Axillary dissection is usually associated with prolonged serous drainage that may result in several complications. We analyzed whether the use of ultrasound scissors may decrease the total amount of drainage from the axilla (AD) in patients requiring curative surgery for breast cancer. Seventy-six women (median age, 56 years; range, 32–73 years) with confirmed pT1–3, N0–1 breast cancer were prospectively randomly assigned to undergo mastectomy or breast-conserving surgery with axillary dissection by either using (group A) or not using (group B) ultrasound scissors. Overall, there was a linear relationship ( P < 0.05) between AD and both total number of the removed nodes and body mass index, whereas no correlation ( P = NS) was found with age and size of the tumor. Total AD was higher (492 ± 153 vs. 408 ± 136 mL, P = 0.013) in group B, whereas the postoperative hospital stay was shorter (2.4 ± 0.6 vs. 2.7 ± 0.7 days, P = NS) in group A. The three-way analysis of covariance using the number of total removed nodes as covariate showed that lymph node status, type of operation, and technique for axillary dissection significantly ( P < 0.05) correlated with AD. In conclusion, our initial study shows that the use of ultrasound scissors significantly reduced total AD in patients requiring axillary dissection and may shorten hospital stay.

The sensitivity of axillary staging when using sentinel node biopsy in breast cancer

AIMS

We aimed to study factors, which enhance the sensitivity of sentinel node biopsy.

METHODS

Three hundred and sixty-three clinically node negative breast cancer patients with successful sentinel node biopsy were studied. All focally radioactive and/or blue nodes in the axilla were harvested. All palpably suspicious lymph nodes were also removed for a similar histological evaluation.

RESULTS

Sentinel node metastases were found in 129 patients. The metastasis was detected in the three first retrieved sentinel nodes in 126 cases and in the fourth or fifth node in three cases. The 'hottest' sentinel node was not the involved one in 18 cases. Five patients with tumour negative sentinel nodes had metastases in other palpably suspicious nodes.

CONCLUSIONS

Harvesting all focally radioactive and/or blue nodes and other palpably suspicious nodes minimises the false negative rate in sentinel node biopsy. Removal of more than five nodes does not significantly improve the sensitivity of axillary staging.

Removal of two sentinel nodes accurately stages the axilla in breast cancer

Background

Assessment of lymph node status in breast cancer is still necessary for staging. Sentinel lymph node biopsy (SNB) may provide accurate staging with less morbidity than axillary clearance. The aim of this study was to assess the effect of the number of sentinel nodes removed on the false-negative rate.

Methods

Data were collected prospectively from 395 women undergoing SNB for breast cancer, between June 1995 and December 2001. All nodes that were hot and/or blue were removed and analysed.

Results

During this interval 136 patients who had SNB were lymph node positive. The median number of sentinel nodes removed was two (range one to five). The overall false-negative rate of SNB in these women was 7·1 per cent. If only one sentinel node had been removed, the false-negative rate would have been 16·5 per cent. The removal of more than two nodes had no effect on axillary staging in all but two women.

Conclusion

In early breast cancer, when there were multiple sentinel nodes, removal of two sentinel nodes significantly reduced the false-negative rate compared with removal of one node. Removing more than two sentinel nodes did not significantly reduce the false-negative rate further.

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.