Factors affecting failed localisation and false-negative rates of sentinel node biopsy in breast cancer--results of the ALMANAC validation phase

Combined 68Ga-NOTA-Evans Blue Lymphoscintigraphy and 68Ga-NOTA-RM26 PET/CT Evaluation of Sentinel Lymph Node Metastasis in Breast Cancer Patients

In this study, we applied a new strategy to identify sentinel lymph node (SLN) metastasis by combining ⁶⁸Ga-NOTA-Evans Blue (⁶⁸Ga-NEB) for SLN mapping and ⁶⁸Ga-NOTA-RM26 for LN metastasis detection in breast cancer patients. A total of 24 female patients with breast cancer diagnosed by core biopsy or suspected by mammography or ultrasonography were recruited and provided informed consent. All patients underwent ⁶⁸Ga-NEB and ⁶⁸Ga-NOTA-RM26 PET/CT imaging. Visual analysis of ⁶⁸Ga-NEB PET/CT images was used to determine SLNs, and then compared with the ⁶⁸Ga-NOTA-RM26 results and histopathological findings. SLNs were visualized in 24 of 24 patients (100.0%) within 4.0-10.0 (5.6 ± 1.4) min. All patients were pathologically diagnosed with breast cancer, and 12 patients had ipsilateral lymph node metastasis. By combining ⁶⁸Ga-NEB and ⁶⁸Ga-NOTA-RM26 images, 7/12 (58.3%) patients showed mild to intense uptake of ⁶⁸Ga-NOTA-RM26 in SLNs, 1/12 patient (8.3%) had moderate uptake of ⁶⁸Ga-NOTA-RM26 in the non-SLNs rather than SLN, indicating possible bypass lymphatic drainage, partially accounting for the false negatives in SLN biopsy during surgery. No false positives were found. The SUV_max of ⁶⁸Ga-NOTA-RM26 activity in metastatic SLNs was significantly higher than that in non-metastatic SLNs (2.2 ± 2.3 vs 0.7 ± 0.1, P = 0.047). This study manifests the value of combination of ⁶⁸Ga-NEB and ⁶⁸Ga-NOTA-RM26 dual tracer PET/CT in preoperative evaluation of SLN metastasis in breast cancer patients, especially in those patients with lymphatic obstruction and bypass drainage. In general, positive ⁶⁸Ga-NOTA-RM26 uptake in either SLN or other lymph nodes can apply lymph node dissection rather than intraoperative SLN biopsy.

Factors that affect the false negative rate of sentinel lymph node mapping with methylene blue dye alone in breast cancer

Objective

This study aimed to investigate the clinicopathological factors of the false negative rate (FNR) and accuracy of sentinel lymph node biopsy (SLNB) mapping with 1% methylene blue dye (MBD) alone, and to examine how to reduce the FNR in patients with breast cancer.

Methods

A total of 365 patients with invasive breast carcinoma who received axillary lymph node dissection after SLNB were retrospectively analyzed. SLNB was performed with 2 to 5 mL of 1% MBD. We studied the clinicopathological factors that could affect the FNR of SLNB.

Results

The identification rate of sentinel lymph nodes (SLNs) was 98.3% (359/365) and the FNR of SLNB was 10.4% (16/154). Multivariate analysis showed that the number of dissected SLNs and metastatic lymph nodes were independent predictive factors for the FNR of SLNB. The FNR in patients with 1, 2, 3, and ≥4 SLNs was 23.53%, 15.79%, 3.85%, and 1.79%, respectively.

Conclusions

SLNB mapping with MBD alone in patients with breast cancer can produce favorable identification rates. The FNR of SLNB decreases as the number of SLNs rises. Because of side effects of searching for additional SLNs and the FNR, removal of three or four SLNs may be appropriate.

Sentinel Lymph Node Biopsy in Early Breast Cancer: Magnetic Tracer as the Only Localizing Agent

BACKGROUND

The combined use of radioisotope and blue dye is the gold standard in sentinel lymph node (SLN) localization in early breast cancer. Superparamagnetic iron oxide (SPIO) has recently emerged as a non-inferior new tracer in sentinel lymph node mapping with fewer disadvantages. This study represents the first and the largest cohort of superparamagnetic iron oxide application in Asian population.

METHODS

Retrospective analysis of a prospectively maintained database was performed from August 2016 to December 2017. All patients with SLN localization by SPIO were included in this study.

RESULTS

A total of 328 breast cancer patients with 333 SLNB procedures were included in this study. Median age was 54 years (range 32-86). Median tumor size was 1.9 cm (range 0.1-12 cm).There were 138 breast-conserving surgeries and 195 mastectomies. All patients received injection of SPIO 1 day prior to operation. A total of 329 successful sentinel lymph node biopsy (SLNB) procedures were undertaken with 1514 sentinel lymph nodes (SLNs) identified. One hundred and fifty-three (10.1%) of the SLNs were positive for malignancy. There were 54 patients with macrometastases, 26 with micrometastases and 24 with isolated tumor cells. Sixty-seven patients underwent subsequent axillary dissection. Four patients failed sentinel lymph node identification with SPIO. The success rate of SPIO in sentinel lymph node localization was 98.8%.

CONCLUSION

SPIO represents a feasible alternative in sentinel lymph node mapping with comparably high nodal detection rate.

Prospective, Multicenter, Randomized Phase III Trial Evaluating the Impact of Lymphoscintigraphy as Part of Sentinel Node Biopsy in Early Breast Cancer: SenSzi (GBG80) Trial

PURPOSE

The aim of the current work was to clarify whether a preoperative lymphoscintigraphy (LSG) enhances staging accuracy of sentinel lymph node biopsy (SLNB).

PATIENTS AND METHODS

In a prospective, multicenter, randomized phase III trial, patients with cN0 early breast cancer or extensive/high-grade ductal carcinoma in situ planned for standard radioactive-labeled colloid LSG with subsequent SLNB were randomly assigned 1:1 to receive SLNB either with knowledge of the LSG findings or without. As the false-negative rate of SLNB correlates with the number of resected sentinel lymph nodes (SLNs), our primary end point was the mean number of histologically detected SLNs per patient. One thousand one hundred two evaluable patients were necessary to demonstrate noninferiority of SLNB without LSG. Stratified one-sided 95% CI for the difference (without LSG − with LSG) in the mean number of histologically detected SLNs had to be greater than −0.27 (10% noninferiority margin). Stratification was performed according to tumor focality and trial site. Additional predefined secondary end points (rates of node-positive patients and of completion axillary lymph node dissection) were analyzed to rule out differences in the reliable detection of nodal metastases.

RESULTS

Between May 2014 and October 2015, 1,198 patients were randomly assigned in 23 German and Swiss breast centers. Modified intention-to-treat analysis (n = 1,163) showed a mean number of histologically detected SLNs of 2.21 with LSG and 2.26 without LSG (difference 0.05; stratified 95% CI, −0.18 to infinity), thus establishing noninferiority of omitting preoperative LSG. Secondary end points displayed no statistically significant differences.

CONCLUSION

We show that SLNB is equally effective irrespective of the surgeon’s knowledge of preoperative LSG results. SLNB without LSG will speed up the preoperative workflow and reduce cost.

A Nomogram Predicting Lymph Node Metastasis in T1 Breast Cancer based on the Surveillance, Epidemiology, and End Results Program

Background: Patients with early stage breast cancer with lymph nodes metastasis were proven to have more aggressive biologically phenotypes. This study aimed to build a nomogram to predict lymph node metastasis in patients with T1 breast cancer.

Methods: We identified female patients with T1 breast cancer diagnosed between 2010 and 2014 in the Surveillance, Epidemiology and End Results database. The patients were randomized into training and validation sets. Univariate and multivariate logistic regressions were carried out to assess the relationships between lymph node metastasis and clinicopathological characteristics. A nomogram was developed and validated by a calibration curve and receptor operating characteristic curve analysis.

Result: Age, race, tumour size, tumour primary site, pathological grade, oestrogen receptor (ER) status, progesterone receptor (PR) status and human epidermal growth factor receptor 2 (HER2) status were independent predictive factors of positive lymph node metastasis in T1 breast cancer. Increasing age, tumour size and pathological grade were positively correlated with the risk of lymph node metastasis. We developed a nomogram to predict lymph node metastasis and further validated it in a validation set, with areas under the receiver operating characteristic curves of 0.733 and 0.741 in the training and validation sets, respectively.

Conclusions: A better understanding of the clinicopathological characteristics of T1 breast cancer patients might important for assessing their lymph node status. The nomogram developed here, if further validated in other large cohorts, might provide additional information regarding lymph node metastasis. Together with sentinel lymph node biopsy, this nomogram can help comprehensively predict lymph node metastasis.

Predictive risk factors for sentinel lymph node nonvisualization on planar lymphoscintigraphy using an intratumoral injection in patients with primary breast cancer

OBJECTIVES

Lymphoscintigraphy is considered a useful tool to optimize sentinel lymph node (SLN) identification. Nonvisualization of the SLN is associated with a lower SLN identification rate. The aim of this study was to identify preoperative factors associated with SLN nonvisualization on lymphoscintigraphy.

PATIENTS AND METHODS

A total of 2050 consecutive SLN procedures were evaluated from clinically node-negative breast cancer patients. Planar lymphoscintigraphy was performed at 3 h after an intratumoral injection of technetium-99m-nanocolloid. This technique was used for extra-axillary SLN identification. Patient, tumor, and treatment characteristics were analyzed for association with SLN nonvisualization. Factors with a P-value less than 0.1 in univariate analysis were included in a multivariate logistic regression model.

RESULTS

The SLN visualization rate was 86.7%. In multivariate logistic regression, age of at least 70 years [odds ratio (OR): 3.24; 95% confidence interval (CI): 2.14-4.91)], BMI of at least 30 (OR: 1.93; 95% CI: 1.39-2.69), T3/T4-tumors (OR: 2.70; 95% CI: 1.37-5.32), medially/centrally located tumors (OR: 1.52; 95% CI: 1.17-1.99), previous mantle field radiation (OR: 4.04; 95% CI: 1.74-9.35), nonpalpable tumors (OR: 1.88; 95% CI: 1.36-2.60), and presence of iodine seeds (OR: 1.35; 95% CI: 1.02-1.78) were associated significantly with nonvisualization on lymphoscintigraphy. Nonvisualization was the strongest independent predictor of unsuccessful intraoperative SLN identification (P<0.001). Overall, the SLN identification rate was 97.7% because of the use of additional imaging and blue dye.

CONCLUSION

This study reports new tumor and treatment-related risk factors for nonvisualization on lymphoscintigraphy by using an intratumoral injection in primary breast cancer. We recommend a periareolar subcutaneous injection to improve SLN visualization in patients with limited prognostic and therapeutic relevance of internal mammary chain SLN identification.

Relationship between Upper Extremity Lymphatic Drainage and Sentinel Lymph Nodes in Patients with Breast Cancer

Purpose

The purpose of this study was to identify the relationship between upper extremity lymphatics and sentinel lymph nodes (SLNs) in breast cancer patients.

Methods

Forty-four patients who underwent axillary reverse mapping (ARM) during axillary lymph node dissection (ALND) with SNL biopsy (SLNB) between February 2017 and October 2017 were investigated. ARM was performed using indocyanine green (ICG) to locate the upper extremity lymphatics; methylene blue dye was injected intradermally for SLN mapping.

Results

ARM nodes were found in the ALND fields of all examined patients. The rate of identification of upper extremity lymphatics within the SLNB field was 65.9% (29 of 44). The ARM nodes were involved in metastases arising from primary breast tumors in 7 of the patients (15.9%), while no metastases were detected in pathologic axillary lymph node-negative patients. Lymphatics from the upper extremity drained into the SLNs in 5 of the 44 patients (11.4%); their ARM-detected nodes were found to be in close proximity to the SLNs.

Conclusions

The ARM nodes and SLNs are closely related and share lymphatic drainage routes. The ARM procedure using fluorescence imaging is both feasible and, in patients who are SLN negative, oncologically safe. ARM using ICG is therefore effective for identifying and preserving upper extremity lymphatics, and SLNB combined with ARM appears to be a promising surgical refinement for preventing upper extremity lymphoedema.

Clinical Trial Registration

This trial is registered with ClinicalTrial.gov: NCT02651142.

Anaphylactic shock due to patent blue: case report and review of literature

Intraoperative search for the sentinal node using patent blue is considered a non risk procedure. We emphasize the highly exceptional nature of this adverse effect previously observed in other disciplines using this coloring agent. We present a case of allergic reaction to patent blue in a patient who underwent left mastectomy with sentinel lymph node. About 25 min after the dye injection, the patient developed increased heart frequency and allergic skin reaction. The patient was treated successfully with decreased inspired fraction of inhaled anesthetic and fluid replacement. The patient recovered uneventfully and was discharged from the PACU 3h after the end of surgery without skin changes and was discharged from hospital on the morning after surgery. Allergic reactions with the use of patent blue are far superior to the hypersensitivity reactions seen with anesthetic and adjuvant drugs. Therefore, the anesthesiologist must be aware of cardiovascular instability associated with skin changes during the use of patent blue, for early diagnosis and appropriate treatment of this hypersensitivity reaction to this dye. Skin tests done later confirmed allergy to patent blue dye; the tests induced a small syndrome reaction. Surgical personnel who use patent blue dye should be made aware of the risk of allergic reactions, sometimes severe, to this dye.

Sentinel Lymph Node Evaluation: What the Radiologist Needs to Know

Axillary lymph node status is the single most important prognostic indicator in patients with breast cancer. Axillary lymph node dissection, the traditional method of staging breast cancer, is associated with significant morbidity. Sentinel lymph node biopsy has become standard in patients being treated for breast cancer with clinically negative lymph nodes. There is considerable variation in the medical literature regarding technical approaches to sentinel lymph node biopsy in patients with breast cancer. The purpose of this article is to describe our preferred approaches to sentinel lymph node biopsy with a review of the literature.

L’exploration axillaire : un standard du bilan préthérapeutique

L’exploration préthérapeutique axillaire est une étape majeure du bilan initial du cancer du sein. L’échographie associée à un prélèvement est actuellement recommandée en première intention. L’IRM et la TEP/TDM au 18FDG sont utiles dans l’évaluation ganglionnaire axillaire. Les sensibilités et spécificités des examens d’imagerie sont globalement identiques, et leur combinaison permet d’obtenir les meilleures performances. Actuellement, la technique du ganglion sentinelle est indispensable en cas de tumeurs mammaires T1-T2 N0 et en cas d’adénopathie suspecte échographiquement avec cytoponction ou microbiopsie négative.

Combination Technique Is Superior to Dye Alone in Identification of the Sentinel Lymph Node in Male Breast Cancer

Sentinel lymph node (SLN) biopsy is the main method in staging the axilla. There are insufficient data available regarding the accuracy of an SLN biopsy in male breast cancer. The aim of this study is to evaluate whether the combination of dye and radiotracer would improve the detection rate of SLNs versus dye alone in male breast cancer patients. From February 2009 to January 2012, our SLN biopsy database was retrospectively reviewed to identify male breast cancer cases. Of the 890 SLN procedures contained in the database, 10 male breast cancer patients were identified. Patient age, body mass index, SLN biopsy technique, SLN identification, number of SLN excised, and pathology reports were reviewed. Mean age was 57.2 (34–85) years with a mean tumor size was 2.2 (1.0–4.0) cm. SLN detection ratios were two in four with blue dye and six in six with the combination technique. Overall, SLNs were identified in 8 of the 10 patients. SLN biopsy is applicable in male breast cancer cases. The addition of a radiotracer to the dye in SLN biopsy increases the detection rate of sentinel nodes in male breast cancer patients.

Sentinel lymph node mapping by near-infrared fluorescence imaging and contrast-enhanced ultrasound in healthy dogs

Sentinel lymph node (SLN) mapping is a valuable and crucial diagnostic procedure in staging malignancies. We compared two non-invasive techniques, near-infrared (NIR) fluorescence imaging and contrast-enhanced ultrasound (CEUS), to identify the SLNs in three superficial anatomical regions in an animal model. Six healthy laboratory dogs were included in a proof-of-concept trial. A NIR fluorescent dye (Indocyanine Green) and microbubbles (Sonovue) were consecutively injected subdermally in the Inguinal, axillary and popliteal region to map the SLNs. Transcutaneous NIR fluorescence imaging identified SLNs in 17 out of a total of 18 occasions. CEUS identified SLNs in all regions (18/18). Whereas NIR fluorescence imaging performed better in the visualization of the afferent lymphatic tract, CEUS demonstrated different filling patterns of the SLNs, a feature potentially critical for the concept of SLN mapping in cancer patients. Both NIR fluorescence imaging and CEUS are safe, non-invasive, practical and accurate methods to perform real-time transcutaneous SLN mapping with potential in a clinical setting.

Surgical staging in endometrial cancer

In several malignancies, it has been demonstrated that the lymph nodal status is the most important pathologic factor affecting prognosis and giving the indication to further adjuvant treatment. The surgical assessment of the lymph nodal status in endometrial cancer is debated since 30 years. Recently, the sentinel lymph node mapping is rapidly gaining clinical acceptance in endometrial cancer. The adoption of Indocyanine Green as a safe and user friendly tracer for sentinel lymph node mapping increased the speed to which this procedure is getting applied in clinical practice. As a consequence of this rapid growth, several fundamental questions have been raised and are still debatable. In this manuscript, we discuss the importance of a known pathological lymph nodal status, the technique of the sentinel lymph node mapping with the reported false negative rates and detection rates according to the different tracers adopted, and the clinical scenarios in which a sentinel lymph node mapping could be employed.

The Sentinel Lymph Node in Breast Cancer: Problems Posed by Examination During Surgery. A Review of Current Literature and Management

The presence of tumor cells can be identified in the lymph node when metastasis has occurred from the primary cancer site into the lymph node (1) If the sentinel lymph node ganglion is negative for the presence of tumor cells at the time of histological examination, the other lymph nodes are also negative in 99% of cases. If no tumor cells are identified in the sentinel lymph node ganglion by histological examination, the other lymph nodes are also negative for the presence of tumor cells in 99% of cases. The sentinel lymph node advantageously replaces axillary dissection as a staging method in breast cancer T1 and T2 (2). Approximately 40% of breast cancers metastasize to axillary lymph nodes and metastatic extension depends on disease stage. Sentinel lymph nodes are affected in the following stages: T1a (4.3%), T1b (19.5%), T1c (23.8%), T2 (48.9%), T3 (66.7%).

Comparison of the indocyanine green dye method versus the combined method of indigo carmine blue dye with indocyanine green fluorescence imaging for sentinel lymph node biopsy in breast conservative therapy for stage ≤IIA breast cancer

BACKGROUND

Fluorescence imaging (FI) is one of the methods to identify sentinel lymph nodes (SLNs). However, the procedure is technically complicated and requires procedural skills, as SLN biopsy must be conducted in dim light conditions. As an improved version of this method, we introduced a combined method (Combined mixed dye and fluorescence; CMF) consisting of indigo carmine blue dye and FI. The direct visualization of SLNs under shadowless surgical light conditions is facilitated by the addition of the blue dye. We compared the SLN detection rates of CMF with that of the indocyanine green (ICG) dye method (ICG-D).

METHODS

A total of 202 patients with stage ≤IIA breast cancer who underwent breast conservative therapy with separate incision from January 2004 to February 2017 were reviewed. Details of the two methods are as follows: (1) ICG-D: 10 mg of ICG was used and the green-stained SLNs were resected via a 3-4 cm axillary incision; (2) CMF: A combination of 5 mg of ICG and 4-8 mg of indigo carmine was used. After a 1.5-2 cm incision was made near the point of disappearance of the fluorescence using Photodynamic Eye (PDE), the blue-stained SLNs were resected under shadowless surgical light conditions.

RESULTS

There were 92 ICG-D and 110 CMF cases. CMF resulted in a significantly higher SLN detection rate than ICG-D (96.4% vs. 83.7%; p = 0.003). This difference was particularly notable in those aged ≥60 years (98.3% vs. 74.3%) and individuals with body mass index (BMI) ≥25 kg/m² (90.3% vs. 58.3%).

CONCLUSION

CMF is an effective method to identify SLNs which is safe and efficient. CMF achieves a high SLN identification rate and most of this procedure is feasible under shadowless surgical light conditions. CMF can reliably perform SLN biopsy even in those aged ≥60 years and individuals with BMI ≥ 25 kg/m².

The importance of tattoo pigment in sentinel lymph nodes

BACKGROUND

The presence of pigment in axillary lymph nodes (LN) secondary to migration of tattoo ink can imitate the appearance of a blue sentinel lymph node (SLN) on visual inspection, causing the operator to either miss the true SLN or excise more than is needed.

OBJECTIVE

We present patients with tattoos ipsilateral to an early stage breast cancer who underwent a SLN biopsy.

METHODS

Patients were retrospectively reviewed from medical records and clinicopathologic data was collected. A total of 52 LNs were retrieved from 15 patients for sentinel mapping and 29 of them had tattoo pigmentation on pathologic evaluation.

RESULTS

Of those 29 SLNs, 2 of them (6.9%) were pigmented, but did not contain either blue dye or Tc-99m (pseudopigmented SLN). Two (3.8%) SLNs were positive for metastasis; both of these had either blue dye or Tc99m uptake, and 1 demonstrated tattoo pigment in the node.

CONCLUSIONS

In this cohort of patients with ipsilateral tattoos, removed more LNs lead to unnecessary excision which may important for increasing the risk of arm morbidity from SLN biopsy. However, the presence of tattoo pigment did not interfere with understaging for axillary mapping and it did not effect of pathological identification of SLNs positivity.

Surgical Standards for Management of the Axilla in Breast Cancer Clinical Trials with Pathological Complete Response Endpoint

Advances in the surgical management of the axilla in patients treated with neoadjuvant chemotherapy, especially those with node positive disease at diagnosis, have led to changes in practice and more judicious use of axillary lymph node dissection that may minimize morbidity from surgery. However, there is still significant confusion about how to optimally manage the axilla, resulting in variation among practices. From the viewpoint of drug development, assessment of response to neoadjuvant chemotherapy remains paramount and appropriate assessment of residual disease—the primary endpoint of many drug therapy trials in the neoadjuvant setting—is critical. Therefore decreasing the variability, especially in a multicenter clinical trial setting, and establishing a minimum standard to ensure consistency in clinical trial data, without mandating axillary lymph node dissection, for all patients is necessary. The key elements which include proper staging and identification of nodal involvement at diagnosis, and appropriately targeted management of the axilla at the time of surgical resection are presented. The following protocols have been adopted as standard procedure by the I-SPY2 trial for management of axilla in patients with node positive disease, and present a framework for prospective clinical trials and practice.

Application of a carbon nanoparticle suspension for sentinel lymph node mapping in patients with early breast cancer: a retrospective cohort study

BACKGROUND

To stage axillary lymph nodes in women with early-stage breast cancer, sentinel lymph node biopsy (SLNB), rather than axillary lymph node dissection (ALND), has been employed. Moreover, different tracer methods have various advantages and disadvantages. In recent years, carbon nanoparticle suspensions (CNSs) have been used as lymph node tracers during surgeries for thyroid cancer, gastric cancer, and colorectal cancer. The study retrospectively analyzed the feasibility and accuracy of CNS for sentinel lymph node (SLN) mapping in patients with early breast cancer.

METHODS

This single-center, retrospective study included breast cancer patients who underwent SLNB from January 1, 2016, to December 31, 2017, in the Department of Breast Cancer, Guangdong General Hospital. All patients received standard SLNB surgery using a CNS tracer.

RESULTS

A total of 332 cases were included in this study. The SLN identification rate was 99.1% (329/332), and the mean number of SLNs was 2.6 (range, 1-6). SLN metastasis was found in 62 (18.8%) cases, of which 90.3% were found to be macrometastases. The sensitivity of SLNB was 95.9% (47/49), with a specificity of 100% (42/42), a positive predictive value of 100% (47/47), a negative predictive value of 95.5% (42/44), and a false-negative rate of 4.1% (2/49).

CONCLUSION

The identification and predictive values of a CNS tracer for SLNB were satisfactory.

Real-time navigation system for sentinel lymph node biopsy in breast cancer patients using projection mapping with indocyanine green fluorescence

BACKGROUND

Inability to visualize indocyanine green fluorescence images in the surgical field limits the application of current near-infrared fluorescence imaging (NIR) systems for real-time navigation during sentinel lymph node (SLN) biopsy in breast cancer patients. The aim of this study was to evaluate the usefulness of the Medical Imaging Projection System (MIPS), which uses active projection mapping, for SLN biopsy.

METHODS

A total of 56 patients (59 procedures) underwent SLN biopsy using the MIPS between March 2016 and November 2017. After SLN biopsy using the MIPS, residual SLNs were removed using a conventional NIR camera and/or radioisotope method. The primary endpoint of this study was identification rate of SLNs using the MIPS.

RESULTS

In all procedures, at least one SLN was detected by the MIPS, giving an SLN identification rate of 100% [95% confidence interval (CI) 94-100%]. SLN biopsy was successfully performed without operating lights in all procedures. In total, 3 positive SLNs were excised using MIPS, but were not included in the additional SLNs excised by other methods. The median number of SLNs excised using the MIPS was 3 (range 1-7). Of procedures performed after preoperative systemic therapy, the median number of SLNs excised using the MIPS was 3 (range 2-6).

CONCLUSIONS

The MIPS is effective in detecting SLNs in patients with breast cancer, providing continuous and accurate projection of fluorescence signals in the surgical field, without need for operating lights, and could be useful in real-time navigation surgery for SLN biopsy.

Evolution in sentinel lymph node biopsy in breast cancer

Sentinel lymph node biopsy (SLNB) is the standard of care for axillary staging in clinically node-negative (cN0) breast cancer patients without neoadjuvant chemotherapy (NAC). The application of SLNB in patients receiving NAC has also been explored. Evidence supports its use after NAC in pretreatment cN0 patients. Nonetheless, its routine use in all the pretreatment node-positive patients who become cN0 after NAC is unjustified due to the unacceptably high false-negative rate, which can be improved in a subset of patients. Axillary surgery omission in selected patients with a low risk of ALN metastasis has gained more and more research interest because the SLNs are tumor-free in more than 70% of all patients. To avoid drawbacks of conventional mapping methods, novel techniques for SLN detection have been developed and shown to be highly accurate in patients with early breast cancer. This article reviews the progress in SLNB in patients with breast cancer.

Comparison of sentinel lymph node detection performances using blue dye in conjunction with indocyanine green or radioisotope in breast cancer patients: a prospective single-center randomized study

Objective:

This randomized study aimed to compare the clinical efficacy between the novel dual tracer composed of indocyanine green (ICG) and blue dye (BD) and the conventional dual tracer composed of radioisotope and BD for sentinel lymph node (SLN) mapping in patients with breast cancer.

Methods:

This study enrolled 471 clinically lymph node-negative patients with primary breast cancer. All patients underwent mastectomy, and those undergoing sentinel lymph node biopsy (SLNB) were randomized to receive blue dye plus radioisotope (RB group) or BD plus ICG (IB group). The detection performances on SLN identification rate, positive SLN counts, detection sensitivity, and false-negative rate were compared between the two groups.

Results:

In the IB group, 97% (194/200) of the patients who underwent the ICG and BD dual tracer injection showed fluorescent-positive lymphatic vessels within 2–5 min. The identification rate of SLNs was comparable between the IB group (99.0%, 198/200) and the RB group (99.6%, 270/271) (P = 0.79). No significant differences were observed in the identification rate of metastatic SLNs (22.5% vs. 22.9%, P > 0.05, RB group vs. IB group, the same below), positive SLN counts (3.72 ± 2.28 vs. 3.91 ± 2.13, P > 0.05), positive metastatic SLN counts (0.38 ± 0.84 vs. 0.34 ± 0.78, P > 0.05), SLNB detection sensitivity (94.4% vs. 92.5%, P > 0.05), or false-negative rate (5.6% vs. 7.5%, P > 0.05) between the two groups.

Conclusions:

ICG can be used as a promising alternative tracer for radioisotope in SLN mapping, and when it is combined with BD in lymphangiography, it offers comparable detection sensitivity compared to the conventional lymphatic mapping strategies that are widely used in clinical practice.

Intraoperative prediction of the two axillary lymph node macrometastases threshold in patients with breast cancer using a one-step nucleic acid cytokeratin-19 amplification assay

The aim of the present study was to assess the sensitivity, specificity and practicality of using a one-step nucleic acid amplification (OSNA) assay during breast cancer staging surgery to predict and discriminate between at least 2 involved nodes and more than 2 involved nodes and facilitate the decision to provide axillary conservation in the presence of a low total axillary node tumour burden. A total of 700 consecutive patients, not treated with neo-adjuvant chemotherapy, received intraoperative sentinel lymph node (SLN) analysis using OSNA for cT1-T3 cN0 invasive breast cancer. Patients with at least one macrometastasis on whole-node SLN analysis underwent axillary lymph node dissection (ALND). The total tumour load (TTL) of the macrometastatic SLN sample was compared with the non-sentinel lymph node (NSLN) status of the ALND specimen using routine histological assessment. In total, 122/683 patients (17.9%) were found to have an OSNA TTL indicative of macrometastasis. In addition, 45/122 (37%) patients had NSLN metastases on ALND with a total positive lymph node burden exceeding the American College of Surgeons Oncology Group Z0011 trial threshold of two macrometastatic nodes. The TTL negative predictive value was 0.975 [95% confidence interval (CI), 0.962-0.988]. The area under the curve for the receiver operating characteristic curve was 0.86 (95% CI, 0.81-0.91), indicating that SLN TTL was associated with the prediction (and partitioning) of total axillary disease burden. OSNA identifies a TTL threshold value where, in the presence of involved SLNs, ALND may be avoided. This technique offers objective confidence in adopting conservative management of the axilla in patients with SLN macrometastases.

Non-visualized sentinel nodes in breast cancer patients; prevalence, risk factors, and prognosis

BACKGROUND

Evidence and consensus is lacking in international guidelines regarding axillary treatment recommendations for patients in whom a sentinel lymph node (SLN) cannot be visualized (non-vSLN) during the sentinel node procedure. In this study we aimed to determine the prevalence of non-vSLNs in a Dutch population of breast cancer patients and to examine predictors and survival rate for non-vSLN.

METHODS

A nationwide, retrospective, population-based study was performed including 116,920 patients with invasive breast cancer who underwent a SLN procedure in the Netherlands between January 2005 and December 2013.

RESULTS

Of the 76,472 clinically negative patients who underwent a SLN procedure, 1924 patients (2.5%) had a non-vSLN, of whom 1552 (80.7%) underwent an ALND. Multivariate analysis showed predictive factors for non-vSLN: older age (p < 0.001), diagnosis in the period 2005-2009 (p < 0.001), larger tumor size (p = 0.003), and extensive nodal involvement (p < 0.001). Multivariate survival analysis showed a significantly worse survival (HR 1.18, 95% CI 1.03-1.34, p = 0.015) for non-vSLNs patients. However, in the non-vSLN group, an ALND was not statistically significantly associated with a better survival (HR 0.96, 95% CI 0.53-1.75, p = 0.891).

CONCLUSION

Patients with non-vSLNs had less favorable disease characteristics and a worse survival compared to patients with a visualized SLN. Performing an ALND was not associated with a significantly better survival in patients with non-vSLNs. However, further research on the necessity of axillary treatment in this specific patient group is required.

Predictive Value of Clinicopathological Characteristics for Sentinel Lymph Node Metastasis in Early Breast Cancer

BACKGROUND Sentinel lymph node biopsy (SLNB) is one of the preferred treatments for breast cancer including clinically negative lymph node breast cancer. However, for 60-70% of patients this invasive axilla surgery is unnecessary. Our study aimed to identify the predictors for sentinel lymph node (SLN) metastasis in early breast cancer patients and provide evidence for rational decision-making in specified clinical situations. MATERIAL AND METHODS Medical records of 417 breast cancer patients who were treated with a breast surgical procedure and SLNB in Ningbo Medical Center Lihuili Eastern Hospital were retrospectively reviewed. Univariate analysis and multivariate logistic regression analysis were used to analyze the correlation between SLN metastasis and clinicopathological characteristics, including patient age, menstrual status, body mass index (BMI), family history, tumor size, laterality of tumor, histological grade, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), Ki67 index, and molecular subtypes of the tumor. RESULTS In the cohort of 417 cases, the ratio of SLNM was 23.0%. Univariate analysis found that age, tumor size, histological grade, and Ki67 index were associated with SLN metastasis. However, age, tumor size, and histological grade were the only three independent predictors for SLN metastasis by multivariate logistic regression analysis. When these three factors were considered together, three different levels of SLN metastasis groups could be classified: low-risk group with the ratio of 14.3%, moderate-risk group with the ratio of 31.4%, and high-risk group with the ratio of 66.7%. CONCLUSIONS Our study demonstrated that age, tumor size, and histological grade were three independent predictive factors for SLN metastasis in early breast cancer patients. This finding may help surgeons in the decision-making process for early breast cancer patients before considering axilla surgical procedure.

Quality Indicators for Sentinel Lymph Node Biopsy in Breast Cancer: Applicability and Clinical Relevance in a Non-screened Population

Quality Indicators for Sentinel Lymph Node Biopsy in Breast Cancer: Applicability and Clinical Relevance in a Non-screened Population: sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) as standard of care for management of early breast cancer. This study assessed our SLNB program against 11 published quality indicators (QIs). All breast cancer patients who underwent SLNB in our centre from June 2013-Dec 2015 were included. Clinical, pathological and follow-up data were extracted from the institutional REDCap data system. Analysis was done with SPSS 23. Following validation, 234 patients had SLNB, always performed along with primary surgery. Identification rate was 95.3% and > 1 SLN was identified in 72% of patients. SLNB positivity was 33%, of these, 100% underwent ALND. Overall 91% of QI eligible patients underwent SLNB. No ineligible patients (T4) underwent SLNB. For the patients who had radio colloid, injection criteria were met for 100%. Pathological evaluation and reporting criteria were met for 100% of patients. There were no axillary recurrences in a median follow-up of 2 years. 7.6% patients had SLN negative on frozen section but positive on final histology. 7.2% of patients with clinical negative nodes had pN2 disease in final histopathology report after surgery. Sixty percent of patients who had completion ALND had only positive SLN. This study supports the applicability of published QI of SLNB in a non-screened cohort of early breast cancer patients. Although QI were useful, modification based on patient characteristics and resource availability may be needed. These indicators can be used as audit tools to improve the overall accuracy of the procedure.

Risk Factors for a False-Negative Result of Sentinel Node Biopsy in Patients with Clinically Node-Negative Breast Cancer

Purpose

Although sentinel lymph node biopsy (SLNB) can accurately represent the axillary lymph node (ALN) status, the false-negative rate (FNR) of SLNB is the main concern in the patients who receive SLNB alone instead of ALN dissection (ALND).

Materials and Methods

We analyzed 1,886 patientswho underwent ALND after negative results of SLNB,retrospectively. A logistic regression analysis was used to identify risk factors associated with a falsenegative (FN) result. Cox regression model was used to estimate the hazard ratio of factors affecting disease-free survival (DFS).

Results

Tumor located in the upper outer portion of the breast, lymphovascular invasion, suspicious node in imaging assessment and less than three sentinel lymph nodes (SLNs) were significant independent risk factors for FN in SLNB conferring an adjusted odds ratio of 2.10 (95% confidence interval [CI], 1.30 to 3.39), 2.69 (95% CI, 1.47 to 4.91), 2.59 (95% CI, 1.62 to 4.14), and 2.39 (95% CI, 1.45 to 3.95), respectively. The prognostic factors affecting DFS were tumor size larger than 2 cm (hazard ratio [HR], 1.86; 95% CI, 1.17 to 2.96) and FN of SLNB (HR, 2.51; 95% CI, 1.42 to 4.42) in SLN-negative group (FN and true-negative), but in ALN-positive group (FN and true-positive), FN of SLNB (HR, 0.64; 95% CI, 0.33 to 1.25) did not affect DFS.

Conclusion

In patients with risk factors for a FN such as suspicious node in imaging assessment, upper outer breast cancer, less than three harvested nodes, we need attention to find another metastatic focus in non-SLNs during the operation. It may contribute to provide an exact prognosis and optimizing adjuvant treatments.

Impact of sentinel lymph node biopsy by ultrasound-guided core needle biopsy for patients with suspicious node positive breast cancer

PURPOSE

The purpose of this study was to investigate the accuracy of preoperative diagnostic tools for axillary lymph nodes (LNs) staging of breast cancer.

MATERIALS AND METHODS

A total of 2464 consecutive patients with operable breast cancer were prospectively identified at our institution between April 2012 and March 2017. Patients with suspicious axillary LN of breast cancer were assessed using preoperative ultrasound(US) or computed tomography (CT), underwent fine-needle aspiration cytology (FNA) or core needle biopsy (CNB). The inclusion criteria for both FNA and CNB were a cortical thickness >3 mm or abnormal morphological characteristics. Patients with biopsy-proven metastasis underwent axillary lymph node dissection (ALND), and those with a negative FNA or CNB underwent sentinel lymph node biopsy (SNB). If the SNB was positive, ALND was performed. Diagnostic accuracy for SNB was calculated for both FNA and CNB. In addition, the patients in this study were divided into two groups as follows: the cN0-FNA group (suspicious LN but negative FNA) and cN0-CNB group (suspicious LN but negative CNB).

RESULTS

A number of patients with negative US/CT findings of LNs were 1406, with 744 undergoing FNA and 272 undergoing CNB for suspicious LNs. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 65, 99, 99, 80, and 85% in FNA, and 87, 100, 100, 93 and 95% in CNB, respectively. SNB was performed in 172 (cN0-CNB group) of 272 CNB and 487 (cN0-FNA group) of 744 FNA patients. One hundred and seventy-two patients from the cN0-CNB group (Tis 6, T1 97, T2 66, T3 3 patients) treated with SNB were compared to 487 from the cN0-FNA group (Tis 21, T1 225, T2 233, T3 8 patients) in terms of number of LN metastasis. A number of patients with more than 3 positive SNB and positive LNs were 9 (5%) and 0 (0%) in cN0-CNB group, and 78 (16%) and 24 (5%) in cN0-FNA group, respectively. A number of patients who had complications such as haematoma and pain at the time of 7 to 14 days after CNB and FNA were 1 (0.5%) and 1 (0.5%) in cN0-CNB group, and were 0% and 0.2% in cN0-FNA group (p = 0.44), respectively.

CONCLUSIONS

The preoperative diagnosis of axillary LNs was influenced by the diagnostic tool used. CNB is a reliable method for the preoperative diagnosis of LN metastasis.

Precise intraoperative sentinel lymph node biopsies guided by lymphatic drainage in breast cancer

The purpose of this study was to present a novel surgical method for intraoperative precise sentinel lymph node biopsy (SLNB) and to determine its clinical efficacy and sensitivity in breast cancer patients. The sentinel lymph nodes (SLNs) were preoperatively evaluated by axillary ultrasound. The intraoperative detection of SLNs was guided by lymphatic drainage pathway. The lymphatic vessels and SLNs were visualized. During operation, we searched for all the true SLNs (trSLNs), para-SLNs (paSLNs) and post-SLNs (poSLNs) followed lymphatic drainage ducts. After precisely locating the lymphatic channels and lymph node, all the lymph nodes that firstly receive lymphatic drainage are designated as trSLNs. We precisely distinguished the trSLNs, paSLNs and poSLNs. We found the average number of trSLNs ranged from1 to 6. In addition, we assessed the novel technique in a total of 125 breast cancer patients. trSLNs were successfully identified in all patients (detection rate: 100 %). The accuracy of trSLNs is 99.2%. Data from our study strongly suggest that our method is a feasible and effective for the detection of precise trSLNs in breast cancer with real-time observations. (ClinicalTrials.gov number, NCT02651142).

Desirable Properties of Radiopharmaceuticals for Sentinel Node Mapping in Patients With Breast Cancer Given the Paradigm Shift in Patient Management

Over the past 2 decades, lymphoscintigraphy and sentinel node biopsy have become widely accepted and are used by surgeons to stage many solid cancers, especially breast cancer. However, despite growing experience, there are a number of unresolved issues. In addition, the impact of a new radiopharmaceutical remains to be determined. The present article addresses some of these issues (either unresolved, recurrent, or newly emerged), with a focus on the properties of radiopharmaceuticals used for sentinel node mapping in breast cancer.

Phase-Transition Nanodroplets for Real-Time Photoacoustic/Ultrasound Dual-Modality Imaging and Photothermal Therapy of Sentinel Lymph Node in Breast Cancer

Pathological status of lymph nodes (LNs) plays a critical role in staging and treatment for the patients with breast cancer. Sentinel lymph node biopsy has become the standard method in determining pathological status of axillary LNs. Therefore, the determination of sentinel lymph nodes (SLNs) and therapy of metastatic LNs are highly desirable in clinic. Herein, an unprecedented carbon nanoparticles (CNs)-incorporated liquid-gas phase-transition nanodroplets (CNPs) with strong near-infrared (NIR) absorption, good biocompatibility, excellent photoacoustic (PA) and ultrasound (US) contrast, and high photothermal-conversion efficiency are reported in this study. Upon laser irradiation, liquid-gas phase transition of the CNPs has been demonstrated to provide excellent contrasts for PA/US dual-modality imaging both in vitro and in vivo. Additionally, the CNPs are capable of staining lymph nodes, which can contribute significantly to the identification of LNs with naked eyes. With increased laser energy, the CNPs exhibit the high performance in killing the breast cancer cells both in vitro and in vivo, due to the photothermal effect induced from the CNs within CNPs. These results suggest that the developed multifunctional phase-transition nanodroplets have high potential to act as the theranostic agents in both SLNs detection and therapy of metastatic LNs.

What to Do with Non-visualized Sentinel Nodes? A Dutch Nationwide Survey Study

Introduction

International guidelines differ regarding their recommendations on axillary treatment of patients with non-visualized sentinel lymph nodes (non-vSLN). Therefore, we distributed a survey among Dutch oncological surgeons to determine their routine practice and opinion regarding axillary treatment in case of a non-vSLN, with the emphasis on whether these practices and opinions have changed since publication of the Z0011 trial.

Methods

A Dutch nationwide survey containing 10 questions regarding clinical routine during the sentinel node procedure and axillary treatment of non-vSLN patients was distributed among 510 oncological surgeons.

Results

The survey was completed by 122 (24%) oncological surgeons, of whom 116 (95%) were registered as specialized breast surgeons. These surgeons had, on average, 13 years of experience. The majority of respondents used both lymphoscintigraphy and Patent Blue during the sentinel node procedure, and 39% estimated the prevalence of a non-vSLN to be 1–2%. Most surgeons are currently more reserved when considering whether to perform an axillary lymph node dissection (ALND) than prior to publication of the Z0011 trial (15 vs. 80%, respectively). Sixty percent base their decision on various clinicopathological characteristics. Twenty-three respondents (20%) opted for an alternative axillary treatment.

Conclusion

This study shows that, in daily practice, most specialized breast surgeons think that a non-vSLN is rare. If so, most currently opt not to perform an ALND, whereas a small proportion consider an alternative axillary treatment. These decisions differ than in the period prior to the Z0011 trial. More research is needed to provide optimal treatment recommendations in case of a non-vSLN.

Electronic supplementary material

The online version of this article (doi:10.1245/s10434-017-5824-4) contains supplementary material, which is available to authorized users.

Optical See-Through Cancer Vision Goggles Enable Direct Patient Visualization and Real-Time Fluorescence-Guided Oncologic Surgery

BACKGROUND

The inability to visualize the patient and surgical site directly, limits the use of current near infrared fluorescence-guided surgery systems for real-time sentinel lymph node biopsy and tumor margin assessment.

METHODS

We evaluated an optical see-through goggle augmented imaging and navigation system (GAINS) for near-infrared, fluorescence-guided surgery. Tumor-bearing mice injected with a near infrared cancer-targeting agent underwent fluorescence-guided, tumor resection. Female Yorkshire pigs received hind leg intradermal indocyanine green injection and underwent fluorescence-guided, popliteal lymph node resection. Four breast cancer patients received ^99mTc-sulfur colloid and indocyanine green retroareolarly before undergoing sentinel lymph node biopsy using radioactive tracking and fluorescence imaging. Three other breast cancer patients received indocyanine green retroareolarly before undergoing standard-of-care partial mastectomy, followed by fluorescence imaging of resected tumor and tumor cavity for margin assessment.

RESULTS

Using near-infrared fluorescence from the dyes, the optical see-through GAINS accurately identified all mouse tumors, pig lymphatics, and four pig popliteal lymph nodes with high signal-to-background ratio. In 4 human breast cancer patients, 11 sentinel lymph nodes were identified with a detection sensitivity of 86.67 ± 0.27% for radioactive tracking and 100% for GAINS. Tumor margin status was accurately predicted by GAINS in all three patients, including clear margins in patients 1 and 2 and positive margins in patient 3 as confirmed by paraffin-embedded section histopathology.

CONCLUSIONS

The optical see-through GAINS prototype enhances near infrared fluorescence-guided surgery for sentinel lymph node biopsy and tumor margin assessment in breast cancer patients without disrupting the surgical workflow in the operating room.

The predictive value of methylene blue dye as a single technique in breast cancer sentinel node biopsy: a study from Dharmais Cancer Hospital

Background

Axillary lymph node dissection (ALND) has been the standard treatment of breast cancer axillary staging in Indonesia. The limited facilities of radioisotope tracer and isosulfan or patent blue dye (PBD) have been the major obstacles to perform sentinel node biopsy (SNB) in our country. We studied the application of 1% methylene blue dye (MBD) alone for SNB to overcome the problem.

Methods

This prospective study enrolled 108 patients with suspicious malignant lesions or breast cancer stages I–III. SNB was performed using 2–5 cc of 1% MBD and proceeded with ALND. The histopathology results of sentinel nodes (SNs) were compared with axillary lymph nodes (ALNs) for diagnostic value assessments.

Results

There were 96 patients with invasive carcinoma from July 2012 to September 2014 who were included in the final analysis. The median age was 50 (25–69) years, and the median pathological tumor size was 3 cm (1–10). Identification rate of SNs was 91.7%, and the median number of the identified SNs was 2 (1–8). Sentinel node metastasis was found in 53.4% cases and 89.4% of them were macrometastases. The negative predictive value (NPV) of SNs to predict axillary metastasis was 90% (95% CI, 81–99%). There were no anaphylactic reactions, but we found 2 cases with skin necrosis.

Conclusions

The application of 1% MBD as a single technique in breast cancer SNB has favorable identification rates and predictive values. It can be used for axillary staging, but nevertheless the technique should be applied with attention to the tumor size and grade to avoid false negative results.

Indocyanine green detects sentinel lymph nodes in early breast cancer

Objective

To explore the clinical value of indocyanine green (ICG) for the fluorescence-guided detection of sentinel lymph nodes (SLNs) during sentinel lymph node biopsy (SLNB) in patients with early breast cancer.

Methods

This retrospective study included female patients with breast cancer. Patients were administered methylene blue and ICG using standard techniques. All SLNs that were collected during surgery were submitted for pathological examination. SLNs were defined as those that were either fluorescent, blue, fluorescent and blue or palpably suspicious. Surgical complications, axillary recurrence, distant metastasis and overall survival rates were observed postoperatively.

Results

A total of 60 patients were enrolled in the study. The fluorescence detection rate of SLNs was 100% (n = 177), with a mean of 2.95 SLNs per patient. The methylene blue staining rate was 88.3% (n = 106), with a mean of 1.77 SLNs per patient. Pathological assessment of intraoperative frozen specimens revealed SLN metastases in 10 patients, who immediately underwent axillary lymph node dissection. No patient had axillary recurrence or distant metastases, with a survival rate of 100%. Patients who underwent SLNB showed good appearance in the axillary wound, with no limited shoulder joint abduction and upper limb oedema.

Conclusion

Fluorescence-guided SLNB has several advantages and is suitable for clinical application.

Analysis of binary responses with outcome-specific misclassification probability in genome-wide association studies

Errors in the binary status of some response traits are frequent in human, animal, and plant applications. These error rates tend to differ between cases and controls because diagnostic and screening tests have different sensitivity and specificity. This increases the inaccuracies of classifying individuals into correct groups, giving rise to both false-positive and false-negative cases. The analysis of these noisy binary responses due to misclassification will undoubtedly reduce the statistical power of genome-wide association studies (GWAS). A threshold model that accommodates varying diagnostic errors between cases and controls was investigated. A simulation study was carried out where several binary data sets (case-control) were generated with varying effects for the most influential single nucleotide polymorphisms (SNPs) and different diagnostic error rate for cases and controls. Each simulated data set consisted of 2000 individuals. Ignoring misclassification resulted in biased estimates of true influential SNP effects and inflated estimates for true noninfluential markers. A substantial reduction in bias and increase in accuracy ranging from 12% to 32% was observed when the misclassification procedure was invoked. In fact, the majority of influential SNPs that were not identified using the noisy data were captured using the proposed method. Additionally, truly misclassified binary records were identified with high probability using the proposed method. The superiority of the proposed method was maintained across different simulation parameters (misclassification rates and odds ratios) attesting to its robustness.

In vivo biodistribution studies and ex vivo lymph node imaging using heavy metal-free quantum dots

Quantum dots (QDs) are attractive photoluminescence probes for biomedical imaging due to their unique photophysical properties. However, the potential toxicity of QDs has remained a major obstacle to their clinical use because they commonly incorporate the toxic heavy metal cadmium within the core of the QDs. In this work, we have evaluated a novel type of heavy metal-free/cadmium-free and biocompatible QD nanoparticles (bio CFQD(®) nanoparticles) with a good photoluminescence quantum yield. Sentinel lymph node mapping is an increasingly important treatment option in the management of breast cancer. We have demonstrated their potential for lymph node mapping by ex vivo imaging of regional lymph nodes after subcutaneous injection in the paw of rats. Using photoluminescence imaging and chemical extraction measurements based on elemental analysis by inductively coupled plasma mass spectroscopy, the quantum dots are shown to accumulate quickly and selectively in the axillary and thoracic regional lymph nodes. In addition, lifetime imaging microscopy of the QD photoluminescence indicates minimal perturbation to their photoluminescence properties in biological systems.

Is blue dye still required during sentinel lymph node biopsy for breast cancer?

Background

In early breast cancer, the optimal technique for sentinel lymph node biopsy (SLNB) is the combined technique (radioisotope and Patent Blue V) which achieves high identification rates. Despite this, many centres have decided to stop using blue dye due to blue-dye-related complications (tattoo, anaphylaxis). We evaluated the SLNB identification rate using the combined technique with and without Patent Blue V and the blue-dye-related complication rates.

Methods

Clinical and histological data were analysed on patients undergoing SLNB between March 2014 and April 2015. SLNB was performed following standard hospital protocols using the combined technique.

Results

A total of 208 patients underwent SLNB and 160 patients (342 nodes) with complete operation notes were available for final analysis. The identification rate with the combined technique was 98.8% (n = 158/160), with blue dye alone 92.5% (n = 148/160) and with radioisotope alone 97.5% (n = 156/160). A total of 76.9% (263/342) of nodes were radioactive and blue, 15.5% (53/342) only radioactive and 2.3% (8/342) only blue, 5.3% (18/342) were neither radioactive nor blue. No anaphylactic reactions were reported and blue skin staining was reported in six (3.8%) patients.

Conclusion

The combined technique should continue be the preferred technique for SLNB and should be standardised. Radioisotope alone (but not blue dye alone) has comparable sentinel node identification rates in experienced hands. National guidelines are required to optimise operative documentation.

Sentinel Lymph Node Biopsy in Breast Cancer: Indications, Contraindications, and Controversies

Axillary lymph node status, a major prognostic factor in early-stage breast cancer, provides information important for individualized surgical treatment. Because imaging techniques have limited sensitivity to detect metastasis in axillary lymph nodes, the axilla must be explored surgically. The histology of all resected nodes at the time of axillary lymph node dissection (ALND) has traditionally been regarded as the most accurate method for assessing metastatic spread of disease to the locoregional lymph nodes. However, ALND may result in lymphedema, nerve injury, shoulder dysfunction, and other short-term and long-term complications limiting functionality and reducing quality of life. Sentinel lymph node biopsy (SLNB) is a less invasive method of assessing nodal involvement. The concept of SLNB is based on the notion that tumors drain in an orderly manner through the lymphatic system. Therefore, the SLN is the first to be affected by metastasis if the tumor has spread, and a tumor-free SLN makes it highly unlikely for other nodes to be affected. Sentinel lymph node biopsy has become the standard of care for primary treatment of early breast cancer and has replaced ALND to stage clinically node-negative patients, thus reducing ALND-associated morbidity. More than 20 years after its introduction, there are still aspects concerning SLNB and ALND that are currently debated. Moreover, SLNB remains an unstandardized procedure surrounded by many unresolved controversies concerning the technique itself. In this article, we review the main indications, contraindications, and controversies of SLNB in breast cancer in the light of the most recent publications.