Status of sentinel lymph node for breast cancer

Accuracy of sentinel lymph node biopsy in male breast cancer: Systematic review and meta-analysis

BACKGROUND

Sentinel lymph node biopsy (SLNB) is commonly used in the surgical management of male breast cancer. Contrary to female breast cancer, limited data exist about its performance in male breast cancer. The objective of this systematic review and meta-analysis was to evaluate the SLNB accuracy in male breast cancer.

METHODS

MEDLINE, EMBASE, Web of Science and The Cochrane Library were searched from January 1995 to April 2023 for studies evaluating the SLNB identification rate and false-negative rate in male breast cancer with negative preoperative axillary evaluation and primary surgery. For SLNB false-negative rate, the gold standard was the histology of axillary lymph node dissection (ALDN). Methodological quality was assessed by using the QUADAS-2 tool. Pooled estimates of the SLNB identification rate and false-negative rate were calculated. Heterogeneity of the pooled studies was evaluated using I2 index.

RESULTS

A total of 12 retrospective studies were included. The 12 studies that reported the SLNB identification rate gathered a total of 164 patients; the 5 studies that reported the SLNB false-negative rate gathered a total of 50 patients with a systematic ALND. The pooled estimate of the SLNB identification rate was 99.0%. The SLNB false-negative rates were 0% in the 5 included studies and consequently so as the pooled estimate of the false-negative rate with no heterogeneity.

CONCLUSION

SLNB for male breast cancer, following negative preoperative axillary assessment and primary surgery, appears feasible, consistent, and effective. Our research supports conducting immediate SLNB histological evaluation to facilitate prompt ALND in case of positive results.

Feasibility of Sentinel Lymph Node Biopsy in Breast Cancer Patients with Axillary Conversion after Neoadjuvant Chemotherapy-A Single-Tertiary Centre Experience and Review of the Literature

(1) Introduction: Sentinel lymph node biopsy (SLNB) is widely used in breast cancer patients who undergo neoadjuvant chemotherapy (NAC), replacing axillary lymph node dissection. While commonly accepted for cN0 patients, its role in cN1/2 patients remains controversial. Our study aims to investigate the role of SLNB in BC patients who underwent prior NAC and compare our results to those of other studies presented in the literature. (2) Materials and methods: Our retrospective study included 102 breast cancer patients who received NAC before 99mTc-albumin Nanocolloid SLN mapping and SLNB was performed, completed or not with axillary dissection. A review based on the PRISMA statement was also carried out, encompassing 20 studies. (3) Results: The lymphoscintigraphy performed after the administration of NAC presented an identification rate (IR) of 93.13%. IR for SLNB was 94.11%, with a false-negative rate (FNR) of 7.4%. After a median follow-up of 31.3 months, we obtained a distant disease-free survival rate of 98%. The results obtained by other groups were similar to those of our study, presenting IR in the range 80.8-96.8%, with FNR varying from 0 to 22%. (4) Conclusions: on conclusion, SLNB can accurately determine the lymph node status, with an acceptable FNR and maintain its expected prognostic role with low recurrence rates, and our results are comparable to those obtained by other studies.

The current role of nuclear medicine in breast cancer

Breast cancer is the most common cancer in females worldwide. Nuclear medicine plays an important role in patient management, not only in initial staging, but also during follow-up. Radiopharmaceuticals to study breast cancer have been used for over 50 years, and several of these are still used in clinical practice, according to the most recent guideline recommendations.In this critical review, an overview of nuclear medicine procedures used during the last decades is presented. Current clinical indications of each of the conventional nuclear medicine and PET/CT examinations are the focus of this review, and are objectively provided. Radionuclide therapies are also referred, mainly summarising the methods to palliate metastatic bone pain. Finally, recent developments and future perspectives in the field of nuclear medicine are discussed. In this context, the promising potential of new radiopharmaceuticals not only for diagnosis, but also for therapy, and the use of quantitative imaging features as potential biomarkers, are addressed.Despite the long way nuclear medicine has gone through, it looks like it will continue to benefit clinical practice, paving the way to improve healthcare provided to patients with breast cancer.

Clinical applications of deep learning in breast MRI

Deep learning (DL) is one of the most powerful data-driven machine-learning techniques in artificial intelligence (AI). It can automatically learn from raw data without manual feature selection. DL models have led to remarkable advances in data extraction and analysis for medical imaging. Magnetic resonance imaging (MRI) has proven useful in delineating the characteristics and extent of breast lesions and tumors. This review summarizes the current state-of-the-art applications of DL models in breast MRI. Many recent DL models were examined in this field, along with several advanced learning approaches and methods for data normalization and breast and lesion segmentation. For clinical applications, DL-based breast MRI models were proven useful in five aspects: diagnosis of breast cancer, classification of molecular types, classification of histopathological types, prediction of neoadjuvant chemotherapy response, and prediction of lymph node metastasis. For subsequent studies, further improvement in data acquisition and preprocessing is necessary, additional DL techniques in breast MRI should be investigated, and wider clinical applications need to be explored.

Utility of Axillary Reverse Mapping (ARM) and Incidence of Metastasis in Arm Draining Lymph Nodes in Patients with Breast Cancer

Objective Lymphedema of the upper limb is the most common complication in patients with breast cancer, who require axillary lymph node (LN) dissection. Proposition of identifying upper limb draining LN and preserving it, during axillary dissection can reduce significant postoperative morbidity, but it has the risk of inadequate oncological resection. This study was planned to find out metastatic rate in axillary reverse mapping (ARM) nodes in our population.

Materials and Methods Lymphoscintigraphy (LSG) was performed using intradermal injection of 99mTc Sulfur Colloid into ipsilateral second and third interdigital web spaces of hand in patients with breast cancer. Planar, single-photon emission computed tomography-computed tomography images were acquired followed by intraoperative localization of arm draining LNs using Gamma Probe. All identified ARM nodes were dissected and sent for histopathological examination to confirm metastatic involvement.

Results Twenty eligible patients were prospectively analyzed. The identification rate of arm draining LN with LSG was 90% (18/20). Among 14 eligible patients included in the study, ARM node metastasis was seen in two patients. A total of 64 ARM nodes were dissected from 14 patients, 4/64 nodes (2 patients) were positive for metastases (6.25%). Of the six patients excluded from the study, in 1 patient ARM node could not be identified on Gamma Probe, in two cases, it could not be retrieved surgically, in next two cases ARM could not be identified on LSG and remaining one case was removed because of previous surgical intervention.

Conclusion In the current study, LSG showed the identification rate of 90% for ARM nodes in patients with carcinoma breast and metastatic involvement was seen in 6.25% (4/64) of these nodes in 2/14 (14.2%) patients, which is in agreement with previously published data. Oncological safety of preserving ARM nodes needs to be evaluated in the larger population.

Sentinel-Lymph-Node Multicenter Trials

Well executed multicenter clinical trials often provide significant evidence and support for, or against, foundational aspects of clinical procedures perceived to improve clinical management of a medical condition. In this review, discussed are reports of multicenter clinical trials designed to investigate sentinel lymph node biopsy procedures in seven types of cancer: breast, melanoma, head and neck, gastric, colon, uterine, and vulvar-with focus on the most recent reports of the hypotheses, objectives, parameters, data, results, implications, and impacts of the included trials. Such trials generally enroll more subjects, in shorter time periods, than do single-center studies. Such studies generally also have greater diversities among investigator practitioners and investigative environments than do single-center studies. The greater number of subjects provides more power to statistical analyses performed in such studies. The more rapid accrual usually results in data being more consistently acquired. The diversities of practitioners and environments may produce results that are more conservative than might be obtained from more "focused" studies; however, diversities in a study often identify implicitly results that are more robust-that is results applicable by more practitioners and applicable in more environments.

Preparation of 99mTc-Labeled Mannan-S-Cysteine and Effect of Molecular Size of Mannan on Its Biodistribution

Macrophage mannose receptor (MMR/CD206) is a promising target for the detection and identification of sentinel lymph node (SLN). MMR-targeting probes have been developed using mannosylated dextran, however, impairment of efficient targeting of SLN was often caused because of retention of injection site in which macrophages and dendritic cells exist. In this study, we prepared new MMR-targeting probes from yeast mannan (85 kDa), and its bioditribution was investigated. In-vivo evaluation showed that 11.9% of injected dose of ^99mTc-labeled mannan-S-cysteines (^99mTc-MSCs) was accumulated in popliteal lymph node (the SLN in this model), however, significant level of radioactivity (approximately 80%) was remained in injection site. Interestingly, ^99mTc-labeled low molecular weight mannan-S-cysteine mannan (^99mTc-LSC) prepared from 50 and 25 kDa mannan showed a decreased specific accumulation of ^99mTc-LSC in the popliteal lymph node, while the radioactivity at the injection site remained unchanged. These results suggest that the molecular size, or nature/shape of the sugar chain is important for the specific accumulation of ^99mTc-MSC in popliteal lymph node.

99mTc-labeled sodium phytate and stannous chloride injection accurately detects sentinel lymph node in axillary of early stage breast cancer: a randomized, controlled study

Aim

The aim of this study was to assess the sentinel lymph node (SLN) detection rate and accuracy of ^99mTc-labeled sodium phytate and stannous chloride (^99mTc-PHY) injection versus ^99mTc-labeled sulfur colloid (^99mTc-SC) injection in sentinel lymph node biopsy (SLNB) in patients with early stage breast cancer.

Methods

A total of 146 consecutive female patients with early stage breast cancer were recruited in this open-labeled, randomized, controlled study. SLNB was conducted on all patients, and ^99mTc-PHY or ^99mTc-SC was used as the radioactive agent (RA). Axillary lymph node dissections were performed in all patients post SLN dissections.

Results

The detection rate of ^99mTc-PHY group was higher compared with that of ^99mTc-SC group (p=0.023), but no difference in the detection rate by dye alone (p=0.190) or by RAs alone (p=0.615) was found between the two groups, and the number of identified SLNs (p=0.100), number of identified SLNs by dye alone (p=0.161), and number of identified SLNs by RA alone (p=0.242) were similar between the two groups. In addition, the sensitivity, specificity, false-negative rate, false-positive rate, and accuracy rate of SLNB showed no difference between ^99mTc-PHY and ^99mTc-SC groups (sensitivity: p=0.645; specificity: p=0.511; false-negative rate: p=0.645; false-positive rate: p=0.511; accuracy rate: p=0.464).

Conclusion

Our study revealed that ^99mTc-PHY was qualified to be a convincing radiopharmaceutical in SLNB.

Impact of Size of the Tumour, Persistence of Estrogen Receptors, Progesterone Receptors, HER2Neu Receptors and Ki67 Values on Positivity of Axillary Lymph Nodes in Patients with Early Breast Cancer with Clinically Negative Axillary Examination

AIM:

The study aimed to identify factors that influence the positivity of axillary lymph nodes in patients with early breast cancer and clinically negative axillary lymph nodes, who were subjected for modified radical mastectomy and axillary lymphadenectomy.

MATERIAL AND METHODS:

This study included 81 surgically treated, early breast cancer patients during the period from 08-2015 to 05-2017. All the cases have been analysed by standard histological analysis including macroscopic and microscopic examination by routine H&E staining. For determination of molecular receptors, immunostaining by PT LINK immunoperoxidase has been done for HER2neu, ER, PR, p53 and Ki67.

RESULTS:

Patients age ranged between 31-73 years, an average of 56.86 years. The mean size of a primary tumour in the surgically treated patient was 20.33 ± 6.0 mm. Axillary dissection revealed from 5 to 32 lymph nodes, with an average of 14. Metastases have been found in 1 to 7 lymph nodes, with an average 0.7. Only 26 (32.1%) of the patients showed metastases in the axillary lymph nodes. The univariant regression analysis showed that the size of a tumour and presence of HER2neu receptors on cancer cells influence the positivity of the axillary lymph nodes. The presence of the estrogen receptors, progesterone receptors have no influence on the positivity for metastatic deposits of lymph nodes. Multivariant model and logistic regression analysis as significant independent factors or predictors of positivity of the axillary lymph nodes are influenced by the tumour size only.

CONCLUSION:

Our study showed that the metastatic involvement of the axillary lymph nodes is mainly influenced by the size of a tumour and presence of HER2neu receptors in the univariant analysis. This point to the important influence of positivity of the axillary lymph nodes but, in multi-variant regressive analysis the lymph node status correlates with the tumour size only.

Secondary node analysis as an indicator for axillary lymphadenectomy in breast cancer patients

INTRODUCTION

Currently, there is no agreement regarding if it would be necessary to perform an axillary lymph node dissection (ALND) in patients who have macrometastases in the sentinel lymph node (SLN). We studied the utility of the secondary node analysis (SN), defined as the following node after the SLN in an anatomical and lymphatic pathway, as a sign of malignant axillary involvement.

METHODS

An observational, retrospective and multicentre study was designed to assess the utility of the SN as a sign of axillary involvement. Among 2273 patients with breast cancer, a valid sample of 283 was obtained representing those who had the SN studied. Main endpoints of our study were: the SLN, the SN and the ALND histological pattern. Sensitivity, specificity and precision of the test were also calculated.

RESULTS

SN test, in cases with positive SLN, has a sensitivity of 61.1%, a specificity of 78.7%, a positive predictive value of 45.8% and a negative predictive value of 87.3% with a precision of 74.7%.

CONCLUSION

The study of the SN together with the technique of the SLN allows a more precise staging of the axillary involvement, in patients with breast cancer, than just the SLN technique.

Elimination of scattered gamma rays from injection sites using upper offset energy windows in sentinel lymph node scintigraphy

OBJECTIVE

The identification of sentinel lymph nodes (SLNs) near injection sites is difficult because of scattered gamma rays. The purpose of this study was to investigate the optimal energy windows for elimination of scattered gamma rays in order to improve the detection of SLNs.

METHODS

The clinical study group consisted of 56 female patients with breast cancer. While the energy was centred at 140 keV with a 20% window for Tc-99m, this energy window was divided into five subwindows with every 4% in planar imaging. Regions of interest were placed on SLNs and the background, and contrast was calculated using a standard equation. The confidence levels of interpretations were evaluated using a five-grade scale.

RESULTS

The contrast provided by 145.6 keV±2% was the best, followed by 140 keV±2%, 151.2 keV±2%, 134.4 keV±2% and 128.8 keV±2% in that order. When 128.8 keV±2% and 134.4 keV±2% were eliminated from 140 keV±10% (145.6 keV±6%), the contrast of SLNs improved significantly. The confidence levels of interpretation and detection rate provided by the planar images with 140 keV±10% were 4.74±0.58 and 94.8%, respectively, and those provided by 145.6 keV±6% were 4.94±0.20 and 100%.

CONCLUSION

Because lower energy windows contain many scattered gamma rays, upper offset energy windows, which exclude lower energy windows, improve the image contrast of SLNs near injection sites.

The role of general nuclear medicine in breast cancer

The rising incidence of breast cancer worldwide has prompted many improvements to current care. Routine nuclear medicine is a major contributor to a full gamut of clinical studies such as early lesion detection and stratification; guiding, monitoring, and predicting response to therapy; and monitoring progression, recurrence or metastases. Developments in instrumentation such as the high-resolution dedicated breast device coupled with the diagnostic versatility of conventional cameras have reinserted nuclear medicine as a valuable tool in the broader clinical setting. This review outlines the role of general nuclear medicine, concluding that targeted radiopharmaceuticals and versatile instrumentation position nuclear medicine as a powerful modality for patients with breast cancer.

Role of FDG PET-CT in evaluation of locoregional nodal disease for initial staging of breast cancer

Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is not indicated or recommended in the initial staging of early breast cancer. Although it is valuable for detecting distant metastasis, providing prognostic information, identifying recurrence and evaluating response to chemotherapy, the role of FDG PET/CT in evaluating locoregional nodal status for initial staging of breast cancer has not yet been well-defined in clinical practice. FDG PET/CT has high specificity but compromised sensitivity for identifying axillary nodal disease in breast cancer. Positive axillary FDG PET/CT is a good predictor of axillary disease and correlates well with sentinel lymph node biopsy (SLNB). FDG PET/CT may help to identify patients with high axillary lymph node burden who could then move directly to axillary lymph node dissection (ALND) and would not require the additional step of SLNB. However, FDG PET/CT cannot replace SLNB or ALND due to unsatisfactory sensitivity. The spatial resolution of PET instruments precludes the detection of small nodal metastases. Although there is still disagreement regarding the management of internal mammary node (IMN) disease in breast cancer, it is known that IMN involvement is of prognostic significance, and IMN metastasis has been associated with higher rates of distant metastasis and lower overall survival rates. Limited clinical observations suggested that FDG PET/CT has advantages over conventional modalities in detecting and uncovering occult extra-axillary especially IMN lesions with upstaging the disease and an impact on the adjuvant management.

Rate of sentinel lymph node identification using isosulfan blue dye in breast cancer patients at Charoenkrung Pracharak Hospital, Thailand

Background: The sentinel lymph node (SLN) is the first lymph node to receive lymphatic drainage from a primary breast tumor. If the SLN contains no metastatic tumor, then it is unlikely other lymph nodes will contain breast cancer metastasis. When the SLN does contains metastasis, an axillary lymph node dissection (ALND) is recommended to further stage the axilla and to maintain locoregional control. SLNs can be identified by using a dye, radioisotope, or combined techniques.

Objective: To determine the rate of SLN identification using isosulfan blue dye in breast cancer patients at Charoenkrung Pracharak Hospital, Thailand, and factors that affect it.

Methods: This prospective study of 106 consecutive cases breast cancer enrolled 105 women (1 bilateral breast cancer case) between October 2011 and October 2013 at Charoenkrung Pracharak Hospital. Clinical and pathological features were analyzed for the effectiveness of SLN identification using isosulfan blue dye.

Results: The rate of SLN identification using isosulfan blue dye in breast cancer patients at Charoenkrung Pracharak Hospital was 92%. The method was safe and well tolerated in early-stage breast cancer patients.

Conclusion: The effectiveness of sentinel node identification using isosulfan blue dye in breast cancer patients at Charoenkrung Pracharak Hospital is consistent with that shown in studies from other countries.

Indocyanine green fluorescence-guided sentinel node biopsy: a meta-analysis on detection rate and diagnostic performance

BACKGROUND

Indocyanine green (ICG) fluorescence-guided sentinel node biopsy (SLNB) has been successfully employed in various kinds of tumors. Clinical results of previous studies on this technique are at different levels of evidence. This Meta-analysis was conducted to provide a more precise estimation on its clinical performance.

METHODS

Eligible studies were identified from systematical PubMed and EMBASE searches; data were extracted. A Meta-analysis was performed to generate pooled detection rate, sensitivity, specificity, diagnostic odds ratio (DOR) and summary receiver operator characteristic curves.

RESULTS

Fifteen published articles were included. Clinical data of 513 patients were obtained. The pooled detection rate, the pooled sensitivity, the pooled specificity, the pooled DOR and their 95% confidence intervals (95% CI) were 0.96 (0.91-0.99), 0.87 (0.79-0.92), 1.00 (0.99-1.00) and 150.13 (57.42-392.56), respectively. Significant heterogeneities existed among studies. Significant publication bias was found in detection rate. The concentration < 5 mg/ml subgroup and the injected volume ≥2 ml subgroup had higher DORs, sensitivities and detection rates than the concentration ≥ 5 mg/ml subgroup and the injected volume <2 ml subgroup, respectively.

CONCLUSION

Based on this Meta-analysis, this technique could be valued promising for detecting the presence of LN metastases. ICG injection with reduced concentration and larger volume may provide improved performance.