Intraoperative detection of sentinel lymph nodes in breast cancer patients using ultrasonography-guided direct indocyanine green dye-marking by real-time virtual sonography constructed with three-dimensional computed tomography-lymphography

PurposeThis study aims to determine the utility of ultrasonography (US)-guided direct dye-marking of sentinel lymph nodes (SLNs) by real-time virtual sonography (RVS) constructed with three-dimensional (3D) computed tomography (CT)-lymphography (LG).Patients and methodsWe identified SLNs in 258 clinically node-negative breast cancer patients using an RVS system to display in real time a virtual multiplanar reconstruction CT image obtained from CT volume data corresponding to the same cross-sectional image from US. CT volume data were obtained using our original 3D CT-LG, which accurately detects SLNs in breast cancer. We then perform US-guided dye-marking close to SLNs using indocyanine green (ICG). Subsequently, indigo carmine blue dye was injected into the subareolar and peritumoral areas around each primary tumor. All patients underwent SLN biopsy and SLN metastases were examined pathologically.ResultsIn all 258 patients, we were able to detect the same SLNs visualized on 3D CT-LG, using the RVS system. We detected ICG close to SLNs in 257 of 258 patients (99.6%) during SLN biopsy. In 25 patients (9%), we failed to follow the blue lymphatic route stained by indigo carmine and SLNs were not stained by indigo carmine, but easily detected SLNs by ICG marking.ConclusionUS-guided direct ICG dye-marking of SLNs using this RVS system seems useful for the detection of SLNs, allowing easy detection of SLNs even when the stained lymphatic route is not followed.     

Practical guidelines for optimal gamma probe detection of sentinel lymph nodes in breast cancer: results of a multi-institutional study. For the University of Louisville Breast Cancer Study Group

INTRODUCTION: Multiple radioactive lymph nodes are often removed during the course of sentinel lymph node (SLN) biopsy for breast cancer when both blue dye and radioactive colloid injection are used. Some of the less radioactive lymph nodes are second echelon nodes, not true SLNs. The purpose of this analysis was to determine whether harvesting these less radioactive nodes, in addition to the "hottest" SLNs, reduces the false-negative rate. METHODS: Patients were enrolled in this multicenter (121 surgeons) prospective, institutional review board-approved study after informed consent was obtained. Patients with clinical stage T1-2, N0, M0 invasive breast cancer were eligible. This analysis includes all patients who underwent axillary SLN biopsy with the use of an injection of both isosulfan blue dye and radioactive colloid. The protocol specified that all blue nodes and all nodes with 10% or more of the ex vivo count of the hottest node should be removed and designated SLNs. All patients underwent completion level I/II axillary dissection. RESULTS: SLNs were identified in 672 of 758 patients (89%). Of the patients with SLNs identified, 403 patients (60%) had more than 1 SLN removed (mean, 1.96 SLN/patient) and 207 patients (31%) had nodal metastases. The use of filtered or unfiltered technetium sulfur colloid had no impact on the number of SLNs identified. Overall, 33% of histologically positive SLNs had no evidence of blue dye staining. Of those patients with multiple SLNs removed, histologically positive SLNs were found in 130 patients. In 15 of these 130 patients (11.5%), the hottest SLN was negative when a less radioactive node was positive for tumor. If only the hottest node had been removed, the false-negative rate would have been 13.0% versus 5.8% when all nodes with 10% or more of the ex vivo count of the hottest node were removed (P =.01). CONCLUSIONS: These data support the policy that all blue nodes and all nodes with 10% or more of the ex vivo count of the hottest SLN should be harvested for optimal nodal staging.     

Sentinel lymph node biopsy in breast cancer: an analysis of the maximum number of nodes requiring excision

Sentinel lymph node biopsy (SNB) is now the standard of care in assessment of patients with clinically staged T1-2, N0 breast cancers. This study investigates whether there is a maximum number of sentinel lymph nodes (SLN) that need to be excised without compromising the false-negative (FN) rate of this procedure. Data were prospectively collected for 319 patients undergoing SNB between February 2001 and December 2006 at our institution. This data were analysed, both in terms of the order of SLN retrieval and relative isotope counts of the SLNs, in order to determine the maximum number of SLNs that need to be retrieved without increasing the FN rate. Furthermore, we investigated the relationship between SLN blue dye concentration and the presence of SLN metastases. The SLN identification rate was 97% with no false-negative cases amongst patients undergoing simultaneous axillary clearance historically during technique validation. In patients with SLN metastases, excision of the first 4 SLNs encountered results in the identification of a metastatic SLN in all cases. Although the majority (86%) of SNB metastases are in the hottest node, the SLN containing the metastasis is in the first 4 hottest nodes in 99% of patients with nodal metastases. The remaining 1% of SLN metastases were identified by blue dye. There was no statistically significant association between the SLN blue dye concentration and the presence of SLN metastases. A policy to remove a maximum of four blue and/or hot SLNs along with any palpably abnormal lymph nodes does not result in an increased false-negative rate of detection of SLN metastases.     

Sentinel lymph node dissection for breast cancer: how many nodes are enough and which technique is optimal?

BACKGROUND: Controversy exists in sentinel lymph node (SLN) mapping in breast cancer regarding the appropriate number of nodes to remove and the best technique for identification of the SLNs. METHODS: A retrospective chart review from January of 1999 to January of 2004 was performed for all patients undergoing a SLN biopsy examination who had at least 1 positive SLN. RESULTS: We identified 167 patients. A mean of 4.4 SLNs were removed per patient. All of the positive SLNs were identified by node 6. Radiotracer used alone identified 19 positive nodes (11.4%) and blue dye used alone identified 14 positive nodes (8.4%). CONCLUSIONS: Our data show that 100% of positive SLNs are found by 6 nodes removed, thereby supporting the concept that the SLN dissection may not be complete by removing only 1 or 2 nodes or only the hottest node. The use of blue dye or radiotracer alone can contribute to the overall false-negative rate.     

Selective Sentinel Lymph Node Dissection for Melanoma: Importance of Harvesting Nodes with Lower Radioactive Counts without the Need for Blue Dye

Background

Determining how many sentinel lymph nodes (SLNs) should be removed for melanoma is important. The purpose of this study is to determine the frequency at which nodes that are less radioactive than the “hottest” node (which is negative) are positive for melanoma, how low of a radioactivity should warrant harvest, and if isosulfan blue is necessary.

Methods

We reviewed 1,152 melanoma patients who underwent lymphoscintigraphy with technetium, with or without blue dye, and SLN dissection from 1996 to 2008. SLNs with radioactivity ≥10% of the “hottest” SLN, all blue nodes, and all suspicious nodes were removed and analyzed. The miss rate was calculated as the proportion of node positive cases in which the “hottest” SLN was negative.

Results

SLNs were identified in 1,520 nodal basins in 1,152 patients. SLN micrometastases were detected in 218 basins (14%) in 204 patients (18%). In 16% of SLN-positive patients (33/204 patients), the positive SLN was found to have a lower radioactive count than the “hottest” SLN, which was negative. In 21 of these cases, the positive SLNs had radioactivity ≤50% of the “hottest” SLN. The 10% rule significantly reduced the miss rate to 2.5% compared with removal of only the “hottest” SLN (miss rate = 16%). Also, blue dye did not significantly decrease the miss rate compared with radiocolloid alone using the 10% rule.

Conclusions

To decrease the miss rate, all SLNs with ≥10% of the ex vivo radioactivity of the “hottest” SLN should be removed and blue dye is not essential.     

Sentinel lymph node biopsies in melanoma: how many nodes do we really need?

BACKGROUND: Sentinel lymph nodes (SLN) biopsy is a widely used method to detect lymphatic spread in patients with cutaneous melanoma. Several methods are used to detect SLNs. Recent reports attempted to identify the adequate number of SLNs to reliably detect malignant spread in regional lymph nodes. METHODS: The radiotracer counts and the pathologic reports of all patients undergoing SLN biopsies were collected prospectively, to determine which of the nodes harboring radiotracer needed to be removed for examination by histopathology between 1998 and 2005. All patients with positive SLN biopsies were investigated in the study. Lymph nodes were ranked according their radiotracer counts and numbered as hottest nodes, second hottest nodes, third hottest nodes, etc. The relationship between radioactivity and the risk of harboring malignancy was determined. RESULTS: Nodal metastases were detected in 55 basins from 53 patients (10.5%). There was a correlation between the radiotracer uptake and risk of harboring malignancy. Excising the 3 hottest nodes and all blue nodes detected 100% of patients with lymphatic malignancy in our series. Most (98%) of positive lymph nodes had radiotracer counts greater than 30% of the hottest node. Only 1 patient (2%) had radioactive count less than 30%, but had visible blue dye. CONCLUSIONS: Removing only the hottest node is inadequate to detect lymphatic spread. On the other hand, removing the 3 hottest nodes and all visible blue nodes is sufficient to detect regional lymphatic spread in patients with cutaneous melanoma. Removing nodes with a radiotracer uptake less than 30% of the hottest nodes may be unnecessary.     

Comparison of the Indocyanine Green Fluorescence and Blue Dye Methods in Detection of Sentinel Lymph Nodes in Early-stage Breast Cancer

Purpose

To assess the diagnostic performance of sentinel lymph node (SLN) biopsy using the indocyanine green (ICG) fluorescence method compared with that using the blue dye method, a prospective multicenter study was performed.

Methods

Patients with T1–3 primary breast cancer without clinical lymph node involvement were included in this study. ICG as a fluorescence-emitting source and indigo carmine as blue dye were injected into the subareolar area. Extracted lymph nodes were examined to identify the first, second, and other SLNs. The identified nodes were classified according to the ICG fluorescence signal and blue dye uptake.

Results

Ninety-nine eligible patients were included in this study. The ICG fluorescence method identified an average of 3.4 SLNs (range, 1–8) in 98 of 99 patients (detection rate, 99 %). The number of lymph nodes identified by the fluorescence method was significantly higher than that identified by the blue dye method (p < 0.001). SLN involvement was identified in 20 % (20 of 99) of patients, all of whom tested positive for the first SLN. In 16 patients, complete axillary lymph node dissection (ALND) was performed. In 25 % (4 of 16) of these patients, axillary metastases were identified; however, no axillary involvement was found in 8 patients with only one involved node, which was isolated as the first SLN.

Conclusions

High rate of SLN detection was achieved using the ICG fluorescence method. The first SLN identified by fluorescence imaging provides an exact indication of the axillary status. Therefore, the ICG fluorescence method provides precise information required to avoid unnecessary ALND.     

Sentinel lymph node biopsy in oral cavity squamous cell carcinoma without clinically evident metastasis

BACKGROUND: The clinically N0 neck in patients with oral SCC is commonly treated by neck dissection because the existence of metastases cannot be excluded. To determine whether unnecessary treatment could be avoided, we evaluated the feasibility of sentinel lymph node (SLN) biopsy. METHODS: Fifteen previously untreated patients with T1 or T2 oral SCC without clinically or radiologically detectable metastasis were included. A blue dye and gamma probe were used to identify SLNs. SLNs were stained with cytokeratins. All nodes in neck dissection specimens were stained using H and E. RESULTS: SLNs were identified in 14 patients by lymphoscintigraphy and in all patients when probe and dye were combined. Four neck dissection specimens contained four metastatic lymph nodes. Three of the four lymph nodes were SLN. One SLN was found to be metastatic after immunostaining. However, although there was one blue sentinel node in one neck, a metastatic non-SLN was present. CONCLUSIONS: Our results show that SLN biopsy is a promising tool for use in patients with oral SCC. However, further studies are necessary.     

Evaluation of sentinel node biopsy by combined fluorescent and dye method and lymph flow for breast cancer

BackgroundConservative breast resection with subsequent sentinel lymph node biopsy (SNB) is an increasingly popular initial approach for the treatment of breast cancer due to decreased invasiveness. SNB is a shorter procedure with fewer side effects than more substantial surgical procedures, but it sometimes fails to identify metastatic disease. Therefore, a highly sensitive and convenient method is needed to identify sentinel lymph nodes (SLN) with a high probability of containing disease in SNB. We compared the combination of radioisotope or dye with a fluorescence compound to analyze lymph flow to identify targets for SNB.Materials and methodsWe examined patients with breast cancer lacking metastases in the axillary lymph node (ALN). Two methods for targeted SNB were developed: (1) Indocyanine Green (ICG) and Patent blue were injected into the skin overlying the tumor and sub-areolar region just before the surgical procedure. (2) ICG and radiocolloid were injected into the skin overlying the tumor and sub-areolar region. The draining fluorescent lymphatic duct was visualized using a Photodynamic Eye (PDE). We removed the SLNs that were identified by the dye and fluorescence imaging methods. Method 1 was applied to 113 patients undergoing SNB, and 29 patients were treated with Method 2. In our study, patients were grouped by lymph flow into two types: Type C demonstrated convergence to one lymph duct. Type S demonstrated separate lymph ducts.ResultsUsing the fluorescence imaging method, 99.3% of SLNs were identified, and 3.8 SLNs per patient were seen. The SLN identification rates for Patent blue dye and radiocolloid were 92.9% and 100%, respectively, while 1.9 and 2.0 SLNs per patient, respectively, were seen with these methods. We classified two types of lymph flow based on the pattern of lymphatic drainage. Type C converged to a single lymph duct, while Type S drained to separate ducts. Type S lymph drainage was seen in 29/142 patients (20.4%), and Type C drainage was found in 113/141 patients (79.6%). Of the patients with Type S drainage, there were 4.1 SLNs per patient, but only 3.4 SLNs per patient were seen in individuals with Type C drainage. Forty cases had metastases found in the ALNs, and five of these cases were dye-negative and fluorescence-positive. Among these cases, the average number of SLNs identified was one.ConclusionThe combination of fluorescence with a visible dye is a highly sensitive method for SLN identification. When SNB is guided by only the dye method, there is a risk of missing appropriate SLNs in patients with Type S lymph drainage or weak dye staining. The use of a fluorescence method together with dye could increase sensitivity of detection in these cases. Furthermore, fluorescent methods are ideal for hospitals that cannot use conventional radioactive measures.     

How many lymph nodes are enough during sentinel lymphadenectomy for primary melanoma?

BACKGROUND: Sentinel lymph node (SLN) biopsy has been shown to reliably identify nodal metastases and the subsequent need for further surgical and adjuvant therapy in patients with cutaneous melanoma. Although SLN identification rates have improved with the addition of radioactive colloid to the blue dye technique, it remains unclear how many lymph nodes should be removed to accurately determine the histologic status of the nodal basin. The objective of this study was to determine the optimal extent of SLN biopsy in these patients. METHODS: The records of 633 consecutive patients with melanoma (765 nodal basins) whose primary treatment included SLN biopsy with the use of a combination of blue dye and technetium Tc 99 labeled sulfur colloid were reviewed. SLN biopsy consisted of the removal of all of the blue-stained nodes and all nodes with radiotracer uptake activity of at least twice background. RESULTS: SLN biopsy was successful in 765 of 772 basins (99%). A mean of 1.9 SLNs (median, 2 SLNs) per basin were excised. At least 3 SLNs were removed in 176 basins (23%). The overall histologic status of a basin was always established by the first or second SLN harvested (ie, in no patient was the third or subsequent SLN positive when 1 of the first 2 was not). Of the 124 basins containing lymphatic metastases, the SLN that contained the maximal radiotracer uptake (hottest) and/or stained blue was pathologically positive in 118 basins (95%). In only 6 of the 124 positive basins (5%) was the sole evidence of occult nodal metastases identified in an SLN that was neither blue-stained nor the hottest. All but 1 of these SLNs had counts that were at least 66% of the hottest node in the basin. CONCLUSIONS: With a combined modality approach to SLN biopsy, removal of more than 2 SLNs did not provide information that upstaged any patient with primary melanoma. Removal of additional nonblue SLN(s) that contained radioactive counts of at least twice background but lower than two thirds of the SLNs with maximal radiotracer uptake affected patient management in less than 0.2% of all cases. These findings may be helpful in minimizing the extent of surgery and perhaps in reducing the costs and resource use associated with operating room time and pathologic examination.     

Evaluation of intraoperative scrape cytology for sentinel lymph node biopsy in patients with breast cancer

The techniques for intraoperative evaluation of sentinel lymph nodes (SLNs) vary. The most common methods include frozen section, imprint cytology/touch preparation cytology, and scrape cytology (SC). The purpose of this study was to evaluate whether there is concordance between the intraoperative SC and the final pathology of SLNs in patients with breast cancer. From October 2001 to June 2005, sentinel lymph node biopsies were attempted in 181 patients with breast cancer using a combination of blue dye and radioisotope. A lymph node was considered an SLN when it was stained with blue dye, had a blue lymphatic afferent, had increased radioactivity, or was abnormal by palpation. SLNs were successfully identified in 180 patients, for an identification rate of 99.4%. Forty-five patients had positive SLNs. In 16 (35%) of those patients, the SLNs were negative intraoperatively by SC. All of the false negatives occurred in SLNs with micrometastases. Thus, SC is an excellent method for identifying macrometastases intraoperatively, but less successful for micrometastases.     

Identification of the regional lymphatic system of the gallbladder by vital staining.

In 21 patients with biliary tract cancer dye was injected into the lymphatic system of the gallbladder to determine the extent of its regional lymph nodes. A volume of 0.1-0.3 ml 1 per cent indigo carmine solution was injected directly into lymphatic vessels of the gallbladder in eight patients and into lymph nodes (cystic node or pericholedochal nodes) in 13 patients during radical surgery for biliary tract cancer. The lymphatic system was visualized in a total of 14 patients. The dye descended around the bile duct, flowed into the cystic node, the pericholedochal nodes and the lymph nodes posterior to the head and neck of the pancreas, and finally reached the interaortocaval nodes adjacent to the left renal vein. The stained lymphatic tissue was regarded as the regional lymphatic system of the gallbladder. These nodes should be completely resected during radical surgery for gallbladder cancer.     

High isotope counts and sentinel node positivity in patients with melanoma

BACKGROUND: Radioisotope mapping is an essential technical component of sentinel lymph node (SLN) biopsy, and most authors define success by an arbitrary threshold SLN-background ratio. HYPOTHESIS: Few studies have examined the degree to which the relative level of SLN counts correlates with the presence of metastasis. Having removed the SLN with the highest counts, there are no data suggesting how far the surgeon should persist in removing additional SLNs that contain much lower levels of isotope. METHODS: We performed 134 SLN biopsy procedures in 132 patients with melanoma. Successful isotope localization was defined using an SLN/"hottest" SLN ratio; we defined an SLN as any node containing counts at least 10% of that of the hottest SLN. RESULTS: Of 83 patients with more than 1 SLN site identified, 21 (25%) had SLNs that contained metastasis. In 17 (81%) of these cases, the SLN with the highest countcontained tumor, but in 4 (19%) it was benign. Among these 4 patients, the counts of the hottest benign SLNs exceeded those of SLNs positive for metastasis on histological examination by a ratio of at least 10:1, and the counts of the positive SLNs were less than 4:1 of those of the background counts or the presence of blue dye failed to identify the positive SLN. No optimum ratio of SLN/SLN or SLN/background counts identified the positive SLN in all cases. CONCLUSIONS: Although the SLN with the highest counts contained metastasis in 81% of patients with malignant melanoma and multiple SLNs, neither a relatively high isotope count nor the presence of blue dye consistently predicted SLN positivity. For maximum accuracy, SLN biopsy requires the removal of all nodes containing isotope regardless of the relative magnitude of counts and the concurrent use of blue dye to salvage those procedures in which isotope mapping fails.     

Sentinel node staging of primary melanoma by the "10% rule": pathology and clinical outcomes

BACKGROUND: Surgical staging of clinically node-negative primary melanoma involves identification and removal of "sentinel" lymph nodes (SLNs). Although some suggest removal of only the "hottest" SLN, the "10% rule" dictates that nodes are removed until the background count is 10% or less of the count of the "hottest" node. METHODS: To determine the utility of the 10% rule, a university database of clinically node-negative melanomas surgically staged by using this rule was examined. RESULTS: Twenty-two of 177 cases (12.5%; 15% of T2 and T3 lesions) were SLN positive. Among the SLN-positive cases, use of the rule resulted in removal of 21 additional nodes, 7 of which contained tumor. In 3 cases (14%), the positive SLN was not the "hottest" node. At 49 months of mean follow-up time, overall survival was 63% for SLN-positive patients versus 92% for SLN-negative patients (P = .01). CONCLUSIONS: Sentinel node staging of melanoma by the 10% rule provides significant prognostic information and a modest increase in tumor detection compared with removal of only the "hottest" node.     

Is the “10% Rule” Equally Valid for All Subsets of Sentinel-Node-Positive Breast Cancer Patients?

Background  In breast cancer, a combination of radioisotope and blue dye mapping maximizes the success and accuracy of sentinel node (SLN) biopsy. When multiple radioactive nodes are present, there is no single definition of isotope success, but the popular “10% rule” dictates removal of all SLN with counts >10% of the most radioactive node. Here we determine how frequently a positive SLN would be missed by the 10% rule. Methods  Between 9/96 and 12/04, we performed 6,369 successful SLN biopsies using ^99mTc sulfur colloid and isosulfan blue dye, removing as SLN all radioactive and/or blue nodes, and taking counts from each node ex vivo. Standard processing of all SLNs with a benign frozen section included hematoxylin and eosin (H&E) staining, serial sectioning, and immunohistochemistry (IHC). Results  33% of patients (2,130/6,369) had positive SLNs. Of these patients, 1,387/2,130 (65%) had >1 SLN identified. The most radioactive SLN was benign in 29% (398/1,387), and 107/1,387 (8%) had a positive SLN that was neither blue nor the hottest. From this group 1.7% (24/1387) of patients had positive SLN with counts <10% radioactive counts of the hottest node. The 10% rule captured 98.3% of positive nodes in patients with multiple SLNs. No patient characteristics were predictive of failure of the 10% rule. Conclusion  With combined isotope and blue dye mapping, the 10% rule is a robust guideline and fails to identify only 1.7% (24/1387) of all SLN-positive patients with multiple SLNs. This guideline appears to be equally valid for all subsets of patients.     

Feasibility of endoscopic sentinel node biopsy in the porcine neck.

OBJECTIVE: To assess the feasibility of endoscopic sentinel node biopsy (SNB) using a tracer dye in a pig model. STUDY DESIGN AND SETTING: This was a prospective, nonrandomized experimental study in Yorkshire pigs. The posterolateral tongues of three animals were injected with a one-to-one solution of carbon dye to methylene blue dye. Endoscopic SNB was performed and stained lymph nodes identified and retrieved, followed by an open dissection to recover any remaining nodes. Specimens were analyzed by a pathologist for staining, size, and structural integrity. RESULTS: Six unilateral endoscopic SNBs were performed without complications. During endoscopic dissection, gross blue-staining of a sentinel node was noted in four of six dissections (66%). One of six sentinel nodes demonstrated histologic evidence of carbon staining. Structural integrity of all nodes was intact upon histological evaluation. CONCLUSION/SIGNIFICANCE: Endoscopic cervical SNB in pigs is feasible but has limitations based on lymph node size and reliability of tracer dyes. Further study is warranted to perfect tracer dyes and retrieval methods to improve this technique.     

Ex vivo sentinel lymph node mapping in colon cancer: improving the accuracy of pathologic staging?

BACKGROUND: A subset of patients with colon cancer staged by conventional methods have occult micrometastases and do not receive adjuvant chemotherapy. Sentinel lymph node (SLN) mapping and staining by immunohistochemistry is a technique that may identify such occult micrometastases, thereby upstaging patients with positive findings. The purpose of this study was to determine whether ex vivo SLN mapping in colon cancer could be applied successfully to patients at our institution. METHODS: Seventeen patients with intraperitoneal colon tumors undergoing resection were studied prospectively. SLNs were identified as the first blue stained node(s) after ex vivo peritumoral injection of isosulfan blue dye. Additional lymph nodes were harvested and processed in accordance with standard pathologic evaluation for colon cancer. All nodes were examined after routine hematoxylin and eosin (H&E) staining. SLNs that were negative on H&E were analyzed further by multilevel sectioning and immunohistochemistry staining using anticytokeratin monoclonal antibody. RESULTS: Of the 17 study patients, SLNs were identified in 16 (94%) cases. The SLN was the only positive node in 3 patients. An identified SLN was positive (by H&E) in all patients with associated positive non-SLN nodes. The average number of nodes retrieved per patient was 16 (range, 4-54). Overall, SLNs accurately reflected the status of the entire lymph node basin in 16 (94%) patients. Two (12%) patients with negative nodes by H&E potentially were upstaged after further SLN analysis. The negative predictive value for SLN mapping was 89%. CONCLUSIONS: The ex vivo technique of SLN mapping for colon cancer is feasible. In the current study, SLN results were concordant with non-SLNs in the majority of patients. Furthermore, this technique may have upstaged 2 (12%) patients. Whether this ultimately will affect overall survival has yet to be determined.     

Evaluation of the benefit of using blue dye in addition to radioisotope for sentinel lymph node biopsy in patients with breast cancer

The techniques for performing sentinel lymph node biopsy (SLNB) vary from institution to institution. Some advocate blue dye only, others radioisotope only, and many utilize a combination of both. The purpose of this study is to evaluate the additional benefit that blue dye provides when used in combination with a radioisotope. From October 2001 to June 2004, 102 SLNBs were attempted in 99 patients with breast cancer using a combination of blue dye and radioisotope. A lymph node was considered a sentinel lymph node (SLN) when it was stained with blue dye, had a blue lymphatic afferent, or had increased radioactivity. Ninety-eight patients had 101 successful identifications of SLNs, for an identification rate of 99%. Twenty-eight patients had positive SLNs. In three of those patients, although there were SLNs identified by both techniques, the positive SLNs were identified with only blue dye. Of the 102 SLNB procedures, there were two patients whose only SLN was identified by blue dye only. Although blue dye did not improve the identification rate, there was a definite benefit in improving the false-negative rate.     

Correlation Between Concordance of Tracers,Order of Harvest,and Presence of Metastases in Sentinel Lymph Nodes With Breast Cancer

Background There are various methods for the detection of sentinel lymph nodes (SLNs) in breast cancer by using a combined method with blue dye and radioisotope (RI) tracers. The purpose of the study was to reveal any correlation between concordance of the tracers and the order of harvest with the presence of metastases in SLNs.Methods The outcomes were reviewed in 408 cases with stage 0 to II breast cancer; the combined method was used in which blue dye and RI were injected subcutaneously around the tumor. The radioactivity and blue staining in each harvested SLN were checked.Results In 330 cases (81%), SLNs contained both blue dye and RI tracers (blue-hot cases), and in 42 (10%) and 31 (8%) cases, the SLNs contained only the blue stain (blue-only cases) and only RI (hot-only cases), respectively. The overall metastatic rate was 25% on a patient basis. Blue-only cases had a higher rate (42%) of metastasis than hot-only cases (14%). The rate of nodes containing both blue dye and RI gradually decreased from the first SLNs harvested to the third SLNs harvested. The rate of nodes containing RI only increased with the number harvested, and there was not so much change in the rate of nodes containing blue only.Conclusions These data suggest that RI tracer could detect a wide range of SLNs and that the blue dye tracer could efficiently detect SLNs with metastasis. The combined methods compensates for the deficiencies of each method and thus will probably help to prevent missing SLNs.Published by Springer Science+Business media, Inc. ©2005 The Society of Surgical Oncology, Inc.     

The definition of the sentinel lymph node in melanoma based on radioactive counts

Background There is no consensus on the definition of a hot, nonblue sentinel lymph node (SLN), despite the widespread use of radiocolloid in SLN mapping. Methods A retrospective review of 592 patients with malignant melanoma who underwent SLN mapping was performed. Ex vivo SLN counts and nodal bed counts were obtained by using a gamma probe. The size of each metastatic deposit in an SLN was defined as macrometastases (>2 mm), micrometastases (≤2 mm), a cluster of cells, or isolated melanoma cells. Results A total of 1175 SLNs (SLN⁻, n=1041; SLN⁺, n=134) were evaluated. The mean SLN count/bed counts were SLN⁻, 322±980 and SLN⁺, 450±910 (not significant [NS]) (>2 mm, 270±792 [NS]; ≤2 mm, 446±693 [NS]; isolated melanoma cells/cluster of cells, 677±1189 [P=.036]). Overall, 16 (1.4%) of the SLNs collected had an overall ratio of ≤2. This included two positive SLNs (1.5%), both of which contained macrometatic disease. Forty-seven positive nodal basins had at least one negative SLN. The hottest SLNs in these basins were negative for metastatic disease in nine cases (19.1%). In one basin (2.1%), the positive SLN count was <10% of the hottest lymph node count. Conclusions Removal of lymph nodes until the bed count is 10% of the hottest lymph node will remove 98% of positive SLNs. Lymph node tumor burden influences radioactive counts.