The Impact of Nonvisualization of Sentinel Nodes on Lymphoscintigraphy in Breast Cancer

Anatomical breast imaging-derived parameters do not provide incremental information in prediction of nonvisualization of sentinel lymph nodes on lymphoscintigraphy

OBJECTIVE

Accurate sentinel lymph node (SLN) staging is essential for both prognosis and treatment in patients with breast cancer. However, the preoperative lymphoscintigraphy may fail to visualize the SLN. The aim of this retrospective study was to investigate whether parameters derived from anatomical breast imaging can predict SLN nonvisualization on lymphoscintigraphy.

METHODS

For this retrospective study, all data of mammography, breast MRI, and lymphoscintigraphy of SLN procedures from January 2016 to April 2021 were collected and reviewed from the Amsterdam UMC database.

RESULTS

A total of 758 breast cancer patients were included in this study. SLN nonvisualization on planar lymphoscintigraphy at 2-h postinjection (pi) was 29.7% and was reduced after a second injection to 7.5% at late lymphoscintigraphy 4-h pi. Multivariable analysis showed that age ≥ 70 years ( P = 0.019; OR, 1.82; 95% CI, 1.10-3.01), BMI ≥ 30 kg/m 2 ( P = 0.031; OR, 1.59; 95% CI, 1.04-2.43), and nonpalpable tumors ( P = 0.034; OR, 1.54; 95% CI, 1.03-2.04) were independent predictors of SLN nonvisualization. Differences in tumor size, Breast Imaging-Reporting and Data System classification, or breast density were not significantly associated with SLN nonvisualization.

CONCLUSION

This study shows that, by using a multivariable analysis, risk factors for SLN nonvisualization in breast cancer patients during preoperative lymphoscintigraphy at 2-h pi are age ≥ 70 years, BMI ≥ 30 kg/m 2 , and nonpalpable tumors. Parameters derived from mammography or breast MRI, however, are not useful to predict SLN nonvisualization on lymphoscintigraphy.

Does failed mapping predict sentinel lymph node metastasis in cN0 breast cancer?

Aims: The clinical significance of nonvisualized sentinel lymph nodes (non-vSLNs) is unknown. The authors sought to determine the incidence of non-vSLNs on lymphoscintigraphy, the identification rate during surgery, factors associated with non-vSLNs and related axillary management. Patients & methods: A total of 30,508 consecutive SLN procedures performed at a single institution from 2000 to 2017 were retrospectively studied. Associations between clinicopathological factors and the identification of SLNs during surgery were assessed. Results: Non-vSLN occurred in 525 of the procedures (1.7%). In 73.3%, at least one SLN was identified intraoperatively. Nodal involvement was only significantly associated with SLN nonidentification (p < 0.001). Conclusion: Patients with non-vSLN had an increased risk for SLN metastasis. The detection rate during surgery was consistent, reducing the amount of unnecessary axillary dissection.

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.

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.

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.

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.

Breast cancer lymphoscintigraphy: Factors associated with sentinel lymph node non visualization

OBJECTIVE

To evaluate factors associated with non identification of the sentinel lymph node (SLN) in lymphoscintigraphy of breast cancer patients and analyze the relationship with SLN metastases.

MATERIAL AND METHODS

A single-center, cross-sectional and retrospective study was performed. Forty patients with lymphoscintigraphy without sentinel lymph node identification (negative lymphoscintigraphy - NL) were enrolled. The control group included 184 patients with SLN identification (positive lymphoscintigraphy - PL). Evaluated factors were age, body mass index (BMI), tumor size, histology, localization, preoperative breast lesion hookwire (harpoon) marking and SLN metastases. The statistical analysis was performed with uni- and multivariate logistic regression models and matched-pairs analysis.

RESULTS

Age (p=0.036) or having BMI (p=0.047) were the only factors significantly associated with NL. Being ≥60 years with a BMI ≥30 increased the odds of having a NL 2 and 3.8 times, respectively. Marking with hookwire seems to increase the likelihood of NL, but demonstrated statistical significance is lacking (p=0.087). The other tested variables did not affect the examination result. When controlling for age, BMI and marking with the harpoon, a significant association between lymph node metastization and NL was not found (p=0.565).

CONCLUSIONS

The most important factors related with non identification of SLN in the patients were age, BMI and marking with hook wire. However, only the first two had statistical importance. When these variables were controlled, no association was found between NL and axillary metastases.

Current status of sentinel lymph-node biopsy in patients with breast cancer

Axillary node status is the most important prognostic indicator for patients with invasive breast cancer. Sentinel lymph-node biopsy (SLNB) is widely accepted and the preferred procedure for identifying lymph-node metastasis. SLNB allows focused excision and pathological examination of the most likely axillary lymph nodes to receive tumor metastases while avoiding morbidities associated with complete axillary nodal dissection. Since its introduction in the early 1990s, the process of SLNB has undergone continual modification and refinement; however, the procedure varies between institutions and controversies remain. In this review, we examine the technical issues that influence the success of lymph node mapping, discuss the controversies, and summarize the indications and contraindications for axillary node mapping and biopsy in clinical practice.

Does Failure to Visualize a Sentinel Node on Preoperative Lymphoscintigraphy Predict a Greater Likelihood of Axillary Lymph Node Positivity?

BACKGROUND

Sentinel lymph node (SLN) mapping has become the standard of care for axillary staging in women with early-stage breast cancer. The purpose of the study was to investigate the hypothesis that nonvisualization of SLN on lymphoscintigraphy (LSG) predicts a subset of patients at risk of having a substantial burden of axillary tumor as evidenced by higher rate of lymph node involvement.

STUDY DESIGN

We retrospectively reviewed the records of 1,500 patients who underwent dual-tracer SLN mapping for breast cancer between 1999 and 2004. LSG were reported as negative or positive.

RESULTS

Ninety-one percent had axillary SLN(s) identified on LSG imaging. In 133 of 134 (99.3%) patients with a negative LSG, SLN(s) was identified intraoperatively either by blue dye or hand-held gamma detection. SLN was positive in 28.4% of LSG nonvisualized group and was positive in 29.1% of LSG visualized group (p>0.05). A significantly higher percentage of women older than 50 years of age had nonvisualization of SLN (p<0.0001). Body mass index (calculated as kg/m2) was >30 in 42.5% of LSG nonvisualized group and in 26.3% in LSG visualized group (p<0.0001).

CONCLUSIONS

Failure to demonstrate axillary uptake by LSG appears to be related to technical factors and patient-related factors, such as body mass index and older age, but does not adversely affect SLN identification. The equivalent rate of positive SLNs in patients with a positive or negative LSG supports the null hypothesis that "failure to visualize" on LSG does not identify a subset of patients at higher risk of being axillary lymph node positive.

Preoperative lymphoscintigraphy predicts the successful identification but is not necessary in sentinel lymph nodes biopsy in breast cancer

BACKGROUND

Although preoperative lymphoscintigraphy in sentinel lymph node biopsy (SLNB) for breast cancer patients is undergone commonly, its clinical significance remains controversial.

METHODS

We retrospectively analyzed our database that contained 636 consecutive breast cancer patients who received preoperative lymphoscintigraphy before SLNB.

RESULTS

The sentinel lymph nodes (SLNs) of 86.5% of patients were well imaged by lymphoscintigraphy, and SLN were located extra-axilla in 5.3% patients. The visualization of SLN in lymphoscintigraphy was not associated with histopathologic type, location, and stage of primary tumor, as well as the time interval from injection of radiocolloid to surgery. The negative lymphoscintigraphy results were associated with excision ;biopsy before injection of radiocolloid and positive axillary node statues. The SLN was successfully detected in 625 (98.3%) enrolled patients. Failure of surgical identification of axillary SLN was associated with whether hot spot was imaged by lymphoscintigraphy. However, we identified axillary SLN in 90 (90.9%) out of 99 patients with negative axillary findings in lymphoscintigram. The false negative rate of SLNB in our study was 16.0% (15 of 94) among patients of training group, and there was no significant difference in the false negative rate between patients who had axillary hot spot in lymphoscintigram and those who had not (P = .273).

CONCLUSIONS

Visualization of SLN in preoperative lymphoscintigraphy predicted the successful SLN identification. However, it was less informative for the location of SLN during operation. Considering the complexity, time consumed, and cost, lymphoscintigraphy should at present be undergone for investigation purposes only.

[Sentinel node detection applied to breast cancer: 2007 update]

The technique of detection and resection of the sentinel lymph node applied to early breast cancer management aims to spare the patient with a low risk of lymph node involvement an unnecessary axillary lymphadenectomy. This innovating technique lies on the double hypothesis of an accuracy to predict non sentinel lymph node status and to induce a lower morbidity when compared with axillary lymphadenectomy. This multidisciplinary technique depends on surgeons, nuclear physicians and pathologists. In practice sentinel lymph nodes are detected thanks to two types of tracers, the Blue and the colloids marked with technetium, harvested by the surgeon guided by the blue lymphatic channel and the use of a gamma probe detection, analyzed by the pathologist according to a particular procedure with the concept of serial slices, and possibly immuno histo chemistry. The objectives of this review are to specify the state of knowledge concerning the different steps: detection, surgical resection and the pathological analysis of the sentinels lymph nodes and to focus on validated and controversial indications, and on the main ongoing trials.