Lymphatic mapping and sentinel lymphadenectomy for breast cancer

Current knowledge of hybrid nanoplatforms composed of exosomes and organic/inorganic nanoparticles for disease treatment and cell/tissue imaging

Exosome-nanoparticle hybrid nanoplatforms, can be prepared by combining exosomes with different types of nanoparticles. The main purpose of combining exosomes with nanoparticles is to overcome the limitations of using each of them as drug delivery systems. Using nanoparticles for drug delivery has some limitations, such as high immunogenicity, poor cellular uptake, low biocompatibility, cytotoxicity, low stability, and rapid clearance by immune cells. However, using exosomes as drug delivery systems also has its own drawbacks, such as poor encapsulation efficiency, low production yield, and the inability to load large molecules. These limitations can be addressed by utilizing hybrid nanoplatforms. Additionally, the use of exosomes allows for targeted delivery within the hybrid system. Exosome-inorganic/organic hybrid nanoparticles may be used for both therapy and diagnosis in the future. This may lead to the development of personalized medicine using hybrid nanoparticles. However, there are a few challenges associated with this. Surface modifications, adding functional groups, surface charge adjustments, and preparing nanoparticles with the desired size are crucial to the possibility of preparing exosome-nanoparticle hybrids. Additional challenges for the successful implementation of hybrid platforms in medical treatments and diagnostics include scaling up the manufacturing process and ensuring consistent quality and reproducibility across various batches. This review focuses on various types of exosome-nanoparticle hybrid systems and also discusses the preparation and loading methods for these hybrid nanoplatforms. Furthermore, the potential applications of these hybrid nanocarriers in drug/gene delivery, disease treatment and diagnosis, and cell/tissue imaging are explained.

Functionalizing tetrahedral framework nucleic acids-based nanostructures for tumor in situ imaging and treatment

Timely in situ imaging and effective treatment are efficient strategies in improving the therapeutic effect and survival rate of tumor patients. In recent years, there has been rapid progress in the development of DNA nanomaterials for tumor in situ imaging and treatment, due to their unsurpassed structural stability, excellent material editability, excellent biocompatibility and individual endocytic pathway. Tetrahedral framework nucleic acids (tFNAs), are a typical example of DNA nanostructures demonstrating superior stability, biocompatibility, cell-entry performance, and flexible drug-loading ability. tFNAs have been shown to be effective in achieving timely tumor in situ imaging and precise treatment. Therefore, the progress in the fabrication, characterization, modification and cellular internalization pathway of tFNAs-based functional systems and their potential in tumor in situ imaging and treatment applications were systematically reviewed in this article. In addition, challenges and future prospects of tFNAs in tumor in situ imaging and treatment as well as potential clinical applications were discussed.

A core-satellite micellar system against primary tumors and their lymphatic metastasis through modulation of fatty acid metabolism blockade and tumor-associated macrophages

Lymph nodes (LNs) are the initial sanctuary of various metastatic tumor cells, and thus a precise lymphatic drug delivery strategy is necessary for the effective inhibition of metastasis. However, the complex biological barriers have restrained the drug delivery to tumor-draining lymph nodes (TDLNs). Metastatic tumor cells would undergo metabolic adaptation towards fatty acid oxidation (FAO) upon reaching the lipid-rich LNs. Herein, to inhibit primary tumors and their lymphatic metastasis, a core-satellite matrix metalloproteinase 2 (MMP-2) responsive micellar system was developed for sequential delivery of paclitaxel (PTX) and the metabolism-regulating drug etomoxir (ET) to tumors and TDLNs, respectively. Upon arrival at the tumor microenvironment (TME), the small satellite micelle encapsulating ET was detached from the core micelle in response to MMP-2, which not only drained to TDLNs via tumor-draining lymphatic vessels and inhibited the FAO of metastatic tumor cells, but also blocked M2-like macrophage polarization in the TME. Meanwhile, the core micelle containing PTX could largely accumulate in the TME and kill tumor cells. In an orthotopic 4T1 breast cancer model, the tumor and TDLN dual-targeted core-satellite micellar system effectively inhibited the growth of the primary tumor and alleviated immune suppression by blocking macrophage polarization. More importantly, tumor lymphatic metastasis was suppressed through FAO metabolic regulation. This strategy provides a promising approach for TDLN targeted therapy against breast cancer and its lymphatic metastasis.

Recent Advances in Sentinel Node Navigation Surgery for Early Gastric Cancer

Maintaining the postoperative quality of life (QOL) while ensuring curability without overtreatment is important in the treatment of early gastric cancer. Postoperative QOL is anticipated to be maintained through minimally invasive function-preserving gastrectomy in early gastric cancer. The concept of the sentinel lymph node (SN) basin is essential to maintain the curability of early gastric cancer using minimally invasive function-preserving gastrectomy. However, additional resection after surgery is difficult to perform in gastric cancer. Thus, the SN basin theory is important. Recently, a multicenter randomized phase III trial in South Korea (SENORITA trial) proved that laparoscopic sentinel node navigation surgery (LSNNS) for stomach preservation results in better postoperative QOL compared with standard gastrectomy in patients with early gastric cancer. LSNNS contributes to patients' QOL based on the concept that curability is not impaired. A multicenter nonrandomized phase III trial is ongoing in Japan, and oncologic safety is expected to be demonstrated. LSNNS has been established as a treatment option for selected patients with early gastric cancer, and its application will become widespread in the future.

Factors Predicting Positive Sentinel Lymph Node Biopsy in Clinically Node-Negative Breast Cancer

Purpose

Sentinel lymph node (SLN) biopsy (SLNB) is the standard tool to stage the axilla of breast cancer patients. This study aimed to identify the predictors of positive SLNB in patients with clinically node-negative breast cancer.

Patients and Methods

A retrospective, single-institution cohort of patients with early-stage breast cancer without clinically identifiable axillary lymphadenopathy was chosen from January 2010 to December 2018. Logistic regression was used to identify possible predictors of positive SLNB.

Results

Four hundred and seventy patients were identified; their mean age was 50±11 years. Most patients had the following characteristics: invasive ductal carcinoma (n=382, 81.3%), unilateral tumor (n=461, 98.1%), unifocal disease (n=351, 74.7%), intermediate grade (n=276, 59.0%), and estrogen and progesterone receptor positivity with human epidermal growth factor receptor 2 negativity (n=305, 64.9%). The mean size of the breast mass was 2.3±1.5 cm. SLNB was positive in 128 (27.2%) cases. The mean number of SLNs was 2±1.2. Axillary lymph node dissection was performed in 109 patients. The mean number of lymph nodes removed was 15±6. In 66 (60.6%) of the 109 patients with metastatic axillary nodes, only the SLNs were found to be positive. The number of SLNs, tumor size, tumor grade, receptor status, prominent axillary lymph nodes, and lymphovascular invasion predicted positive SLNB (P = 0.01, 0.03, 0.03, and 0.04 and <0.001 and <0.001, respectively).

Conclusion

Our results suggest that a number of histopathological and radiological characteristics of breast cancer can predict SLNB positivity in clinically node-negative breast cancer patients.

iTRAQ proteomics of sentinel lymph nodes for identification of extracellular matrix proteins to flag metastasis in early breast cancer

Patients with early breast cancer are affected by metastasis to axillary lymph nodes. Metastasis to these nodes is crucial for staging and quality of surgery. Sentinel Lymph Node Biopsy that is currently used to assess lymph node metastasis is not effective. This necessitates identification of biomarkers that can flag metastasis. Early stage breast cancer patients were recruited. Surgical resection of breast was followed by identification of sentinel lymph nodes. Fresh frozen section biopsy was used to assign metastatic and non-metastatic sentinel lymph nodes. Discovery phase included iTRAQ proteomics coupled with mass spectrometric analysis to identify differentially expressed proteins. Data is available via ProteomeXchange with identifier PXD027668. Validation was done by bioinformatic analysis and ELISA. There were 2398 unique protein groups and 109 differentially expressed proteins comparing metastatic and non-metastatic lymph nodes. Forty nine proteins were up-regulated, and sixty proteins that were down regulated in metastatic group. Bioinformatic analysis showed ECM-receptor interaction pathways to be implicated in lymph node metastasis. ELISA confirmed up-regulation of ECM proteins in metastatic lymph nodes. ECM proteins have requisite parameters to be developed as a diagnostic tool to assess status of sentinel lymph nodes to guide surgical intervention in early breast cancer.

The bright future of nanotechnology in lymphatic system imaging and imaging-guided surgery

Lymphatic system is identified the second vascular system after the blood circulation in mammalian species, however the research on lymphatic system has long been hampered by the lack of comprehensive imaging modality. Nanomaterials have shown the potential to enhance the quality of lymphatic imaging due to the unparalleled advantages such as the specific passive targeting and efficient co-delivery of cocktail to peripheral lymphatic system, ease molecular engineering for precise active targeting and prolonged retention in the lymphatic system of interest. Multimodal lymphatic imaging based on nanotechnology provides a complementary means to understand the kinetics of lymphoid tissues and quantify its function. In this review, we introduce the established approaches of lymphatic imaging used in clinic and summarize their strengths and weaknesses, and list the critical influence factors on lymphatic imaging. Meanwhile, the recent developments in the field of pre-clinical lymphatic imaging are discussed to shed new lights on the design of new imaging agents, the improvement of delivery methods and imaging-guided surgery strategies.

A CT-based Radiomics Model for Prediction of Lymph Node Metastasis in Early Stage Gastric Cancer

RATIONALE AND OBJECTIVES

To develop and validate a CT-based radiomics model for preoperative prediction of lymph node metastasis (LNM) in early stage gastric cancer (EGC).

MATERIALS AND METHODS

Four hundred and sixty-three consecutive EGC patients were enrolled in this retrospective study. Radiomics features were extracted from portal venous phase CT scans. A radiomics signature was built based on highly reproducible features using the least absolute shrinkage and selection operator method. The predictive performance of radiomics signature was tested in the training and testing cohorts. Multivariate logistic regression analysis was conducted to build a radiomics-based model combined radiomics signature and lymph node status according to CT. Performance of the model was determined by its discrimination, calibration, and clinical usefulness.

RESULTS

The radiomics signature comprised six robust features showed significant association with LNM in both cohorts. A radiomics model that incorporated radiomics signature and CT-reported lymph node status showed good calibration and discrimination in the training cohort (AUC = 0.91) and testing cohort (AUC = 0.89). Decision curve analysis confirmed the clinical utility of this model.

CONCLUSION

The CT-based radiomics model showed favorable accuracy for prediction of LNM in EGC and may help to improve clinical decision-making.

Recent updates and current issues of sentinel node navigation surgery for early gastric cancer

With the increase in the incidence of early gastric cancer (EGC), several endoscopic and laparoscopic approaches, such as endoscopic submucosal dissection and function-preserving gastrectomy, have been accepted as standard treatments. Sentinel node navigation surgery (SNNS) is an ideal surgical option for preservation of most parts of the stomach and consequent maintenance of normal gastric function to improve quality of life in patients with EGC. Although many previous studies and clinical trials have demonstrated the safety and feasibility of the sentinel node concept in gastric cancer, the clinical application of SNNS is debatable. Several issues regarding technical standardization and oncological safety need to be resolved. Recently several studies to resolve these problems are being actively performed, and SNNS might be an important surgical option in the treatment of gastric cancer in the future.

Is the intraoperative frozen section analysis of sentinel lymph nodes necessary in clinically negative node breast cancer?

Purpose

Although metastasis occurs in 1 or 2 sentinel lymph nodes (SLNs), axillary lymph node dissection (ALND) has been widely not performed. For axillary staging and management, the necessity of intraoperative frozen section analysis of SLN has been controversial. The aim of this study is to evaluate the validity and benefit of SLN analysis by permanent section alone in clinically negative lymph node breast cancer patients.

Methods

We conducted a retrospective study of 283 cases with negative node clinical findings between July 2018 and August 2019 in Samsung Medical Center. Clinical nodal stage was evaluated by physical examination, breast ultrasonography, breast magnetic resonance imaging, and chest computerized tomography. The cases were divided into 2 groups; the permanent group had 151 cases (53.4%) and the frozen group had 132 cases (46.6%). We retrospectively analyzed the differences in the number of metastatic lymph nodes and rates of performed ALND between the 2 groups.

Results

Baseline and clinicopathologic characteristics between the 2 groups were well balanced. Three cases in the permanent group and 6 cases in the frozen group underwent additional or immediate ALND. The rates of ALND between the 2 groups were not significantly different (P = 0.312). The cased of 78.9% and 89.5% with metastatic lymph nodes in permanent and frozen groups were in the pathologic N1 stage, respectively.

Conclusion

SLNs analysis by permanent section alone may be performed in clinically negative axillary node breast cancer patients. Our findings can help to avoid unnecessary intraoperative frozen section analysis.

Sentinel lymph node detection differs when comparing lymphoscintigraphy to lymphography using water soluble iodinated contrast medium and digital radiography in dogs

Sentinel lymph node (SLN) mapping by various means has become standard of care in certain types of human cancers and is receiving more attention in veterinary oncology. Current SLN mapping techniques can be costly and often require advanced imaging equipment. The objective of this prospective, method comparison study was to compare an SLN mapping protocol of lymphoscintigraphy to lymphography using water soluble iodinated contrast medium (WIC) and digital radiography for identification of an SLN. Lymphoscintigraphy and lymphography were performed on eight healthy purpose-bred dogs using technetium-99m sulfur colloid and WIC injected into the subcutaneous tissues in a four-quadrant technique around a predefined area of skin on the brachium. Images were obtained using a gamma camera and digital radiography at different time points post-injection. Image sequences were evaluated by one of two American College of Veterinary Radiology board-certified veterinary radiologists. Data obtained were compared between methods using descriptive statistics. An SLN was identified in all dogs with lymphoscintigraphy and seven of eight dogs with lymphography. Agreement between results of the lymphoscintigraphy and lymphography studies was a complete match in three dogs, a partial match in four dogs, and no match in one dog. The SLN detected differed based on the imaging modality used.

The effect of surgery on lymphoscintigraphy drainage patterns from the canine brachium in a simulated tumor model

OBJECTIVE

To determine the effect of surgery on lymphoscintigraphy drainage patterns from the canine brachium.

STUDY DESIGN

Experimental study.

ANIMALS

Eight healthy research beagles.

METHODS

A predefined area of skin measuring 2 × 1.5 cm in dimension was designated on either the right or left brachium. Preoperative lymphoscintigraphy was performed with technetium sulfur colloid injected into the subcutaneous tissues around the predefined anatomic location in a four-quadrant technique. Dogs underwent surgery for excision of the predefined area of skin, subcutis, and fascia of the lateral head of the triceps muscle with 1-cm margins. Eighteen days after surgery, lymphoscintigraphy was again performed with technetium sulfur colloid injected into the subcutaneous tissues around the surgical scar in a four-quadrant technique.

RESULTS

Sentinel lymph nodes were identified in eight of eight dogs preoperatively and in eight of eight dogs postoperatively. Agreement between the results of the preoperative and postoperative lymphoscintigraphy studies was identified as complete in four of eight dogs and partial in four of eight dogs. Sentinel lymph node identification occurred immediately in three of eight dogs preoperatively and in eight of eight dogs postoperatively.

CONCLUSION

Sentinel lymph node identification occurred faster postoperatively. Agreement or partial agreement between the results of the preoperative and postoperative lymphoscintigraphy studies was observed in eight of eight dogs.

CLINICAL SIGNIFICANCE

Surgery appears to have an effect on lymphoscintigraphy drainage patterns. Additional studies are required to compare preoperative and postoperative sentinel lymph node mapping patterns in tumor-bearing dogs. However, this study provides preliminary information regarding the effect of surgery on sentinel lymph node identification.

Feasibility and surgical impact of Z0011 trial criteria in a single-Institution practice

The purpose of this study is the evaluation of clinical and surgical impact of the Z0011 trial criteria on the management of breast cancer (BC) patients undergoing breast conservative surgery (BCS) at the European Institute of Oncology (IEO). We studied 1386 patients who underwent BCS and sentinel lymph node biopsy (SLNB) from July 2016 to July 2018. Clinical evaluation, breast ultrasound, mammogram, and cyto/histological examination were performed for all patients at the time of diagnosis. Frozen sections of the sentinel lymph node (SLN) were not performed for any patient. Patients who underwent neo-adjuvant therapy were excluded. To evaluate the results before and after the introduction of Z0011 criteria, a group of 1425 patients with the same characteristics who underwent BCS and SLNB from July 2013 to July 2015 were analyzed. We studied the characteristics of the patients by nodal status, and we observed that T stage, tumor grade, and lymphovascular invasion were statistically related with the highest rate of positive SLN. Of the 1386 patients who underwent surgery after the introduction of the Z011 trial, 1156 patients (83.4%) had negative SLN, 230 patients (16.6%) had positive SLN. Subsequent axillary lymph node dissection (ALND) was performed in only 7 cases (3.0%). Of the 1425 patients operated before the introduction of the Z0011 trial, 216 patients had subsequent ALND (15%). The reduction in the number of ALND performed after the introduction of Z0011 is statistically significant, and this could result in a remarkable reduction of the comorbidities of our patients.

A radiomics-based model for prediction of lymph node metastasis in gastric cancer

PURPOSE

To develop and validate a radiomics-based model for preoperative prediction of lymph node metastasis (LNM) in gastric cancer (GC).

METHOD

A total of 768 GC patients were enrolled in this retrospective study. Radiomics features were extracted from portal venous phase computed tomography (CT) scans. A radiomics signature was built with highly reproducible features using the least absolute shrinkage and selection operator (LASSO) method in the training cohort (n = 486). The signature was further validated in internal validation (n = 240) and external testing cohorts (n = 42). Multivariate logistic regression analysis was conducted to build a model that combined radiomics signature, serum biomarkers, and lymph node status according to CT. Performance of the model was determined by its discrimination, calibration, and clinical usefulness. The predictive value of the model was also evaluated in early stage GC (EGC) subgroup.

RESULTS

The radiomics signature comprised 7 robust features showed favorable prediction efficacy in all cohorts. A radiomics-based model that incorporated radiomics signature, serum CA72-4, and CT-reported lymph node status had good calibration and discrimination in training cohort [AUC, 0.92; 95% confidence interval (CI), 0.89-0.95] and validation cohort (AUC 0.86; 95% CI, 0.81-0.91). The model also showed a favorable predictive performance for EGC patients with an AUC of 0.85 (95% CI, 0.76-0.94). Decision curve analysis confirmed the clinical utility of this model.

CONCLUSIONS

The radiomics-based model showed favorable accuracy for prediction of LNM in GC. The model may also serve as a noninvasive tool for preoperative evaluation of LNM in EGC.

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.

Clinical feasibility of imaging with indocyanine green combined with carbon nanoparticles for sentinel lymph node identification in papillary thyroid microcarcinoma

BACKGROUND

Although several previous studies demonstrated the feasibility and efficacy of indocyanine green (ICG) for thyroid cancer surgery, ICG was administered through venous injection and focused on parathyroid gland protection. We thus aimed to study the feasibility of imaging using ICG combined with carbon nanoparticles (CNs) in the identification of sentinel lymph nodes (SLNs) in patients diagnosed with papillary thyroid microcarcinoma (PTMC).

METHODS

Two approaches were applied to detect lymph nodes in PTMC surgery. Patients were randomized into 2 groups. ICG and CNs were injected into the thyroid in Group A. In Group B, only CNs was injected. Black-stained or fluorescent nodes observed using near-infrared fluorescence imaging systems were defined as SLNs. SLN and central lymph node (CLN) dissection was completed in both groups. The pathological and postoperative outcomes were compared between 2 groups.

RESULTS

There were 40 patients in Group A and 60 in Group B. A total of 138 SLNs were identified; 72 and 66 SLNs were detected and dissected in Groups A and B, respectively. The number of SLNs identified (per patient) in Group A was higher than that in Group B (P = .027). The number of harvested CLNs was 161 and 192 in Groups A and B, respectively, out of which 45 and 48 lymph nodes with metastasis were confirmed by permanent pathology. The CLN metastatic rate in Group A was higher than that in Group B (P = .048).

CONCLUSION

Imaging using ICG combined CNs is feasible and safe for SLN identification in PTMC patients. Compared with using only CNs, more SLNs can be removed and more metastatic lymph nodes can be confirmed when using the combined method. Although the combined method appears to accurately stage tumors, further research is needed.

Novel Hybrid Dextran-Gadolinium Nanoparticles as High-relaxivity T1 Magnetic Resonance Imaging Contrast Agent for Mapping the Sentinel Lymph Node

OBJECTIVES

To assess the applicability of a novel hybrid dextran-gadolinium nanoparticles (NPs) as high-relaxivity T1 magnetic resonance imaging (MRI) contrast agent for mapping the sentinel lymph node (SLN).

METHODS

Dextran-bis-acrylamide-polyacrylic acid (Dex-MBA-PAA) NPs were synthesized through a self-assembly assisted approach and complexed with multiple chelated gadolinium (Gd) (III) ions. After their characterization was validated, they were used to mapping SLNs by MRI in Wistar rats, and their biosafety was evaluated.

RESULTS

Dextran-MBA-polyacrylic acid-Gd NPs have suitable particle size and much higher longitudinal relaxivity (r1) than that of commonly used clinical MRI contrast agents (eg, gadopentetic acid dimeglumine salt injection). The in vivo T1-weighted MRI results revealed their effectiveness at mapping SLNs. And their biological safety was also verified.

CONCLUSIONS

Dextran-MBA-polyacrylic acid-Gd NPs were synthesized and validated by in vitro and in vivo experiments for their ability to visualize SLNs by MRI with accurate positioning and excellent biosafety, and they have great potential for clinical SLN mapping.

Near Infrared Fluorescent Lymph Node Mapping with Indocyanine Green in Breast Cancer Patients: A Prospective Trial

BACKGROUND

Near infrared (NIR) fluorescence imaging is an emerging modality that can enable real-time image-guided procedures. Indocyanine green (ICG) is an FDA-approved, inexpensive, and widely available NIR dye. We hypothesized that axillary lymphatic mapping with ICG is equivalent to lymphatic mapping with technetium 99m (^99mTc) in breast cancer patients.

STUDY DESIGN

Breast cancer patients (cT1-2, N0) were prospectively enrolled. Patients underwent lymphatic mapping with ^99mTc preoperatively and ICG mapping intraoperatively (0.8 mL). Sentinel lymph node (SLN) biopsy was guided by NIR camera and gamma probe. Rate of failed mapping, number of SLNs identified, and rate of identifying pathologically positive SLNs were compared between the 2 techniques (p < 0.05 was considered statistically significant).

RESULTS

Ninety-two female patients were enrolled (median age 59 years). Mean transit time from ICG injection in the breast to localization in the axilla was 5 minutes (range 2 to 29 minutes). No adverse reactions to ICG were noted. Mean number of SLNs identified with ICG and ^99mTc was 2.4 (SD 1.42) and 2.2 (SD 1.23), respectively (p = 0.34). Pathologically positive SLNs were identified in 18 (19.8%) patients. A total of 24 pathologically positive SLNs in 18 patients were identified by ICG in 24 of 24 (100%) patients and by ^99mTc in 23 of 24 (96%) patients (p = 0.99).

CONCLUSIONS

Indocyanine green with NIR fluorescence imaging can be safely and efficiently used for real-time intraoperative lymphatic mapping in breast cancer patients. Indocyanine green performs similarly to ^99mTc with regard to the number of SLNs identified, rate of failed mapping, and identification of pathologically positive SLNs.

Positive non-sentinel axillary lymph nodes in breast cancer with 1-2 sentinel lymph node metastases

Recent clinical trials have shown that sentinel lymph node biopsy (SLNB) alone without axillary lymph node dissection (ALND) can offer excellent regional control if there is sentinel lymph nodes (SLN) metastases to 1-2 nodes. This study aimed to explore the predictive factors for non-sentinel lymph node (NSLN) metastasis in breast cancer patients with 1-2 positive SLNs.Patients with breast cancer and 1-2 positive SLN admitted between March 2009 and March 2017 and who underwent ALND after SLN biopsy (SLNB) at Beijing Chaoyang Hospital were analyzed retrospectively. Factors influencing the status of NSLN were studied by univariate and multivariate analysis.Of 1125 patients, 147 patients had SLN metastasis (13.1%) and 119 patients (81.0%) had 1-2 positive SLNs. Among them, 42 patients (35.3%) had NSLN metastasis. The invasive tumor size (P <.001), histological grade (P =.011), lymphovascular invasion (LVI) (P =.006), and over-expression of HER2 (P =.025) significantly correlated with non-SLN metastasis by univariate analysis. LVI (LVI) (P =.007; OR: 4.130; 95% confidence interval [CI]: 1.465-11.641), invasive tumor size (P <.001; OR: 7.176; 95% CI: 2.710-19.002), and HER2 over-expression (P =.006; OR: 5.489; 95% CI: 1.635-18.428) were independently associated with NSLN metastasis by the Logistic regression model. The ROC analysis identified a cut-off point of 26 mm of tumor size (area under the receiver operating characteristic [ROC] curve [AUC] 0.712, CI: 0.614-0.811) was useful for dividing patients with positive SLN (1-2 nodes) into non-SLN-positive and non-SLN-negative groups.For 1-2 positive SLNs of breast cancer, LVI, large invasive tumor size, and HER2 over-expression are independent factors affecting NSLN metastases.

Frequency and Predictors of Axillary Lymph Node Metastases in Iranian Women with Early Breast Cancer

Background:

Axillary lymph node metastasis is the most important predictive factor for recurrence risk and survival in patients with invasive breast carcinoma. The aim of this study was to determine factors associated with metastatic involvement of axillary lymph nodes in Iranian women with early breast cancer.

Methods:

This article reports a retrospective study of 774 patients with T1-T2 breast cancer who underwent resection of the primary tumor and axillary staging by SLNB and/or ALND between 2005 and 2015 at our institution.

Results:

Of the 774 patients included in this study, 35.5% (275 cases) had axillary lymph node involvement at the time of diagnosis. Factors associated with nodal involvement in univariate analyses were tumor size, lymphovascular invasion (LVI), tumor grade, ER/PR status and HER2 expression. All factors identified with univariate analyses were entered into a multivariate logistic regression model and tumor size (OR= 3.01, CI 2.01–4.49, P <0.001), ER/PR positivity (OR = 1.74, CI 1.1.16–2.62, P = 0.007) and presence of LVI (OR = 3.3.8, CI 2.31–4.95, P <0.001) remained as independent predictors of axillary lymph node involvement.

Conclusions:

In conclusion, the results of this study suggests that positive hormonal receptor status, LVI and tumor size are predictive factors for ALNM in Iranian women with early breast cancer.

Morbidity of Selective Lymph Node Biopsy for Melanoma: Meta-Analysis of Complications

Background and Aim

Intraoperative lymphatic mapping and selective lymph node biopsy is accepted worldwide as the standard procedure for staging regional lymph nodes of 1–4 mm thick melanomas, as well as for other neoplasms. Although it is often stated that selective lymph node biopsy is a minimally invasive procedure associated with few complications, few data exist concerning the morbidity associated with the procedure. The present analysis was performed to evaluate the morbidity associated with selective lymph node biopsy in a long-term follow-up.

Materials and Methods

The study provides a review of 437 selective lymph node biopsies on 269 patients, operated on between the 1994 and the 2009, for the lymph node biopsy of head and neck, groin, axilla, upper and lower limbs and nodal basins. Patients’ history and follow-up were reviewed for 2 weeks after surgery, every 3 months for the first 2 years, every 4 months during the third year, and every 6 months subsequently, and postoperative morbidity was evaluated.

Results

After sentinel node biopsy, 14 patients developed one of the following complications: hematoma, 1 case (0.30%); lymphedema, 1 case (0.30%); seroma, 2 cases (0.61%); wound infection, 6 cases (1.83%); keloid scar, 2 cases (0.61%); and postoperative pain, 2 cases (0.61%). The total complication rate was 4.26%.

Conclusions

Selective lymph node biopsy for melanoma, as for other tumors, in respect to radical lymphadenectomy, is not a complications-free procedure but is usually not severe.

Ultrasound-Guided Fine-Needle Aspiration of Non-palpable and Suspicious Axillary Lymph Nodes with Subsequent Removal after Tattooing: False-Negative Results and Concordance with Sentinel Lymph Nodes

Ultrasonography-guided fine-needle aspiration (US-guided FNA) for axillary lymph nodes (ALNs) is currently used with various techniques for the initial staging of breast cancer and tagging of ALNs. With the implementation of the tattooing of biopsied ALNs, the rate of false-negative results of US-guided FNA for non-palpable and suspicious ALNs and concordance with sentinel lymph nodes were determined by node-to node analyses. A total of 61 patients with breast cancer had negative results for metastasis on US-guided FNA of their non-palpable and suspicious ALNs. The biopsied ALNs were tattooed with an injection of 1-3 mL Charcotrace (Phebra, Lane Cove West, Australia) ink and removed during sentinel lymph node biopsy or axillary dissection. We determined the rate of false-negative results and concordance with the sentinel lymph nodes by a retrospective review of surgical and pathologic findings. The association of false-negative results with clinical and imaging factors was evaluated using logistic regression. Of the 61 ALNs with negative results for US-guided FNA, 13 (21%) had metastases on final pathology. In 56 of 61 ALNs (92%), tattooed ALNs corresponded to the sentinel lymph nodes. Among the 5 patients (8%) without correspondence, 1 patient (2%) had 2 metastatic ALNs of 1 tattooed node and 1 sentinel lymph node. In multivariate analysis, atypical cells on FNA results (odds ratio = 20.7, p = 0.040) was independently associated with false-negative FNA results. False-negative ALNs after US-guided FNA occur at a rate of 21% and most of the tattooed ALNs showed concordance with sentinel lymph nodes.

Chemotherapy port related lymphedema after axillary lymph node dissection

The Mascagni lymphatic pathway comprises superficial channels along the clavicle that drain upper extremity lymph. A 65 year-old woman with recurrent left breast cancer presented with a non-functioning chemotherapy port in the right deltopectoral groove. She had undergone right mastectomy with axillary lymph node dissection (ALND). After port removal and wound closure she developed right upper extremity lymphedema. Patients who have undergone ALND may depend solely on this pathway for upper extremity lymphatic drainage.

LEVEL OF EVIDENCE

level V.

Intradermal microbubbles and contrast-enhanced ultrasound (CEUS) is a feasible approach for sentinel lymph node identification in early-stage breast cancer

BACKGROUND

Microbubbles and contrast-enhanced ultrasound (CEUS) is a new technique for locating sentinel lymph node (SLN). The aim of this study is to explore the feasibility of SLNs tracing by CEUS using microbubbles in breast cancer patients and the value of enhancing patterns in diagnosing lymph nodes metastases.

METHODS

A clinical trial was registered (trial registration: ChiCTR-DDT-13003778). One hundred and one consecutive consenting patients with breast cancer undergoing SLN biopsy were enrolled. Before the surgery, microbubble was injected periareolarly. Lymphatic drainage pathway was detected by CEUS, and guidewire was deployed to locate the SLN before the operation. Blue dye was also used to help in tracing sentinel lymph node during the operation. The identification rate and the accuracy rate were recorded. Enhancing patterns of lymph nodes were recorded and compared with the pathological diagnosis.

RESULTS

Of the 101 cases, SLNs in 99 cases were successfully identified by at least one tracer, including 98 cases identified by CEUS and 97 cases by blue dye. There was no significant difference between the two methods (P = 0.705). Guidewires were deployed successfully in all 98 cases, and the localized SLNs were all isolated successfully in the following operations. The status of SLNs isolated by CEUS was completely identical to that of the whole axillary lymph node while 7.1 % cases were misdiagnosed as negative by blue dye method. The sensitivity of predicting SLNs metastases by CEUS enhancing pattern was 81.8 %, the specificity was 86.2 %, and the positive and negative predictive values were 75.0 and 90.3 %, respectively.

CONCLUSIONS

Microbubbles and CEUS are feasible approaches for SLN identification. The enhancing patterns on CEUS may be helpful to recognize the metastasizing SLNs. This novel method may be a promising technique for the clinical application.

A Novel Treatment Method for Lymph Node Metastasis Using a Lymphatic Drug Delivery System with Nano/Microbubbles and Ultrasound

Chemotherapy based on hematogenous administration of drugs to lymph nodes (LNs) located outside the surgically resected area shows limited tissue selectivity and inadequate response rates, resulting in poor prognosis. Here, we demonstrate proof of concept for a lymphatic drug delivery system using nano/microbubbles (NMBs) and ultrasound (US) to achieve sonoporation in LNs located outside the dissection area. First, we demonstrated the in vitro effectiveness of doxorubicin (Dox) delivered into three different tumor cell lines by sonoporation. Sonoporation increased the Dox autofluorescence signal and resulted in a subsequent decrease in cell viability. Next, we verified the antitumor effects of Dox in vivo using MXH10/Mo-lpr/lpr mice that exhibit systemic lymphadenopathy, with some peripheral LNs reaching 10 mm in diameter. We defined the subiliac LN (SiLN) as the upstream LN within the dissection area, and the proper axillary LN (PALN) as the downstream LN outside the dissection area. Dox and NMBs were injected into the SiLN and delivered to the PALN via lymphatic vessels; the PALN was then exposed to US when it had filled with solution. We found that sonoporation enhanced the intracellular uptake of Dox leading to high cytotoxicity. We also found that sonoporation induced extravasation of Dox from lymphatic endothelia and penetration of Dox into tumor tissues within the PALN. Furthermore, our method inhibited tumor growth and diminished blood vessels in the PALN while avoiding systemic toxic effects of Dox. Our findings indicate that a lymphatic drug delivery system with sonoporation represents a promising method for treating metastatic LNs located outside the dissection area.

Advances in research of fluorescence imaging for detection of gastrointestinal tumors

Fluorescence imaging, which has a high sensitivity, produces images by capturing fluorescence signal from the inside of organisms. Over the past few years, notable development of fluorescence imaging technique has been made in the field of gastrointestinal cancer. Imaging instruments and fluorescent probes for fluorescence imaging are being improved and innovated, making it a promising technique for broad clinical applications in the near future. Future clinical applications of fluorescence imaging include aiding diagnosis and surgical treatment of gastrointestinal tumors, which are important development directions of this technique. However, increasing the safety and the accuracy for tumor detection is a challenge for fluorescence imaging. Besides, in order to acquire better diagnostic effects, the combination of fluorescence imaging and other imaging modalities which require novel imaging probes for tumor is also an important trend for fluorescence imaging development.

Metastatic breast cancer cells in lymph nodes increase nodal collagen density

The most life-threatening aspect of breast cancer is the occurrence of metastatic disease. The tumor draining lymph nodes typically are the first sites of metastasis in breast cancer. Collagen I fibers and the extracellular matrix have been implicated in breast cancer to form avenues for metastasis. In this study, we have investigated extracellular matrix molecules such as collagen I fibers in the lymph nodes of mice bearing orthotopic human breast cancer xenografts. The lymph nodes in mice with metastatic MDA-MB-231 and SUM159 tumor xenografts and tumor xenografts grown from circulating tumor cell lines displayed an increased collagen I density compared to mice with no tumor and mice with non-metastatic T-47D and MCF-7 tumor xenografts. These results suggest that cancer cells that have metastasized to the lymph nodes can modify the extracellular matrix components of these lymph nodes. Clinically, collagen density in the lymph nodes may be a good marker for identifying lymph nodes that have been invaded by breast cancer cells.

Simultaneous mapping of pan and sentinel lymph nodes for real-time image-guided surgery

The resection of regional lymph nodes in the basin of a primary tumor is of paramount importance in surgical oncology. Although sentinel lymph node mapping is now the standard of care in breast cancer and melanoma, over 20% of patients require a completion lymphadenectomy. Yet, there is currently no technology available that can image all lymph nodes in the body in real time, or assess both the sentinel node and all nodes simultaneously. In this study, we report an optical fluorescence technology that is capable of simultaneous mapping of pan lymph nodes (PLNs) and sentinel lymph nodes (SLNs) in the same subject. We developed near-infrared fluorophores, which have fluorescence emission maxima either at 700 nm or at 800 nm. One was injected intravenously for identification of all regional lymph nodes in a basin, and the other was injected locally for identification of the SLN. Using the dual-channel FLARE intraoperative imaging system, we could identify and resect all PLNs and SLNs simultaneously. The technology we describe enables simultaneous, real-time visualization of both PLNs and SLNs in the same subject.

Real-time fluorescence imaging of abdominal, pleural, and lymphatic metastases

Virally-directed fluorescence imaging has the potential to revolutionize intra-operative oncologic staging and tumor resection. Many viruses genetically engineered to specifically infect tumor cells as cancer therapy can be further modified to have a visible marker gene for cancer staging. In this chapter, we describe such a herpes simplex virus (HSV) modified to be detected by fluorescence. Other viruses so designed can be similarly used in cancer detection and staging. Replication-competent, tumor-specific HSV NV1066 expresses green fluorescent protein (GFP) in infected cancer cells. One single dose of NV1066 administered via intratumor, intracavitary, or systemic injection can spread within and across body cavities to target tumor cells while sparing normal tissue cells from infection. Tumors otherwise invisible by conventional laparoscopy appear green with the use of an endoscope equipped with a fluorescent filter. Furthermore, with GFP expression easily visualized by stereomicroscopy, microscopic, and pathologic analysis is significantly enhanced. This chapter addresses NV1066-directed visualization of peritoneal, pleural, and lymphatic metastases. This chapter also provides protocols for the production of tumor models in various body cavities in rodents.

How many sentinel lymph nodes are enough for accurate axillary staging in t1-2 breast cancer?

Purpose

During a sentinel lymph node biopsy (SLNB) for breast cancer, the appropriate number of sentinel lymph nodes (SLNs) to be removed for accurate axillary staging is still controversial. We hypothesized that there might be an optimal threshold number of SLNs. We investigated how many SLNs should be removed to achieve an acceptable accuracy and ensure minimal morbidity.

Methods

We reviewed data of 328 patients with invasive breast cancer who underwent SLNB followed by complete level I and II axillary dissection between January 2004 and December 2005. The false negative rate (FNR) and accuracy of SLNB according to the number of removed SLNs were evaluated.

Results

The mean number of SLNs removed was 3.0 (range, 1-14), and that of total retrieved axillary lymph nodes was 17.5 (range, 10-40). In total, 111 (33.8%) patients had positive nodes on the permanent pathological report. Among them, 12 patients had negative SLNs; thus, the overall FNR of SLNB was 10.8% (12/111) and the accuracy was 96.3% (316/328). The FNR was 26.6% for a single SLN, 8.0% for two, and 11.1% for three. In cases where four or more SLNs were removed, the FNR decreased to 0% and accuracy reached 100%.

Conclusion

Our data suggest that a SLNB should not only remove one or two of the hottest node(s) when other hot nodes exist. We also suggest that four might be an optimal threshold number of SLNs to be removed and that removal of more than four SLNs does not improve axillary staging accuracy.

Nuclear beta-catenin overexpression in metastatic sentinel lymph node is associated with synchronous liver metastasis in colorectal cancer

BACKGROUND

Beta-catenin, a component of the Wingless/Wnt signaling pathway, can activate target genes linking with the adenomatous polyposis coli (APC) gene in colorectal cancer. The purpose of this study is to investigate whether nuclear beta-catenin overexpression in metastatic sentinel lymph node(s) [SLN(s)] is associated with synchronous liver metastasis.

METHODS

Clinicopathological data from 355 patients (93 cases with liver metastasis and 262 cases without liver metastasis) were reviewed. Beta-catenin expression in metastatic SLN(s) and liver metastatic lesions was examined by immunohistochemistry. The association of nuclear beta-catenin expression in metastatic SLN(s) and liver metastatic lesions was evaluated, and the relationship between nuclear beta-catenin expression and clinicopathological characteristics was analyzed. Finally, univariate and logistic multivariate regression analyses were adopted to discriminate the risk factors of liver metastasis.

RESULTS

Nuclear beta-catenin overexpression in metastatic SLN(s) was observed in 70 patients with liver metastasis and 31 patients without liver metastasis (75.3% vs. 11.8%; P < 0.001). Nuclear beta-catenin expression was noted in all the metastatic lesions. Spearman rank correlation analysis demonstrated that nuclear beta-catenin expression in metastatic SLN(s) had a positive correlation with that in metastatic lesions (r = 0.425, P < 0.001). Univariate and multivariate analyses indicated that nuclear beta-catenin overexpression in metastatic SLN(s) correlated with liver metastasis.

CONCLUSIONS

Nuclear beta-catenin overexpression in metastatic SLN(s) is strongly associated with liver metastasis and may contribute to predict liver metastasis.

Role of axillary staging in women diagnosed with ductal carcinoma in situ with microinvasion

BACKGROUND

Axillary staging via sentinel node biopsy (SLNB) in patients with ductal carcinoma in situ with microinvasion (DCISM) is routinely performed but remains controversial with regard to the risk-benefit ratio.

METHODS

Retrospective single-institution review of patients with diagnosis of DCISM (invasive tumor ≤ 0.1 cm). Age, clinicopathologic data, and follow-up were recorded.

RESULTS

Of 90 patients, 33% were diagnosed by core needle biopsy (CNB), 37% by excisional biopsy, and 29% were upstaged from DCIS on CNB to DCISM at final operation. Three (10%) of 30 patients with DCISM on CNB were upstaged to invasive cancer on final pathology. Median age at diagnosis was 58.9 years (range: 30-89). Lumpectomy was performed in 45% of patients and mastectomy in 55%. Mean number of sentinel nodes was 2.59 (SE 0.17). Six (6.9%) of 87 patients with DCISM as final diagnosis had a positive SLNB (four lumpectomies, two mastectomies). There was no correlation with any clinicopathologic features, including palpable DCIS, DCIS grade/necrosis, or age at diagnosis. All six SLNB-positive patients had a complete axillary dissection; two had additional disease. Median follow-up time was 74.2 months (range: 2-169). In-breast recurrence was seen in three patients (5%), regardless of SLN status, DCIS grade, or necrosis. Two patients developed distant metastasis. Overall survival was 94.19% at 5 years for DCISM and 100% for DCISM with nodal disease.

CONCLUSION

DCISM comprises 0.6% of breast cancer diagnoses at our institution. There is a low likelihood of nodal spread; however, a lack of identifiable clinicopathologic features associated with a positive SLNB limits selective SLNB use.

Role of intra-operative touch imprint cytology in the treatment of breast cancer

OBJECTIVES

A prospective study was carried out to evaluate the role of intra-operative touch imprint cytology (TIC) in the assessment of sentinel lymph node (SLN) involvement for staging and treatment of early-stage, clinically node-negative breast carcinoma.

METHODS

Forty-five patients with early-stage, clinically node-negative breast cancer underwent a SLN biopsy with intra-operative TIC. The SLN was bisected if its width was less than 4 mm or sliced every 2 mm if it was more than 4 mm. The imprint specimens were stained with haematoxylin and eosin (H&E). Rapid immunochemistry (IH) was performed in case of equivocal cytological result. Permanent sections were evaluated with H&E and IH staining. The results of TIC were compared to histopathological results.

RESULTS

The sensitivity, specificity and overall accuracy of TIC on a node basis were 65.5%, 96.3%, 85.5%, respectively. When calculated according to the size of SLN metastasis, the sensitivity of TIC for overt metastasis was 84.6%, while it was 62.5% for micrometastasis and 37.5% for sub-micrometastasis. The mean size of nodal metastasis was 5.08 mm and 1.25 mm for true positive and false negative results, respectively (P = 0.0236). Because of intra-operative TIC, 76.5% of the patients who needed further axillary lymph node dissection (ALND) could undergo this during the same operating time.

CONCLUSIONS

TIC is a rapid and reliable method for the intra-operative assessment of metastatic sentinel node involvement in patients with early-stage, clinically node-negative breast carcinoma. Despite a low sensitivity comparable to frozen section (FS) in detecting micro- and sub-micrometastases, the technique offers the advantage of full tissue preservation for subsequent histological analysis.

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

INTRODUCTION

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Practical applications of nuclear medicine in imaging breast cancer

The rise in incidence, morbidity, and mortality of breast cancer has triggered multiple imaging efforts to detect this malignancy early, stage it accurately, and monitor it with precision in the posttherapeutic course. Among different imaging modalities, nuclear medicine provides an important contribution to the clinical management of breast cancer. This article discusses four practical applications based on the use of radionuclides in the evaluation of breast malignancy, focusing on scintimammography, preoperative tumor localization procedure using radioactive seeds, sentinel nodal scintigraphy, and F-18 fluorodeoxyglucose positron emission tomography/computed tomography.

Quantitative RT-PCR detection of tumor cells in sentinel lymph nodes isolated from colon cancer patients with an ex vivo approach

OBJECTIVE

To investigate quantitative RT-PCR-based detection of tumor cells in lymph nodes (LNs) isolated from colon cancer patients by ex vivo sentinel lymph node (SLN) mapping.

SUMMARY BACKGROUND DATA

Although lymph node status is among the strongest prognostic factors in colon cancer patients, 20% to 30% of node negative patients experience disease recurrence. These patients may have LN metastases that are not detected by routine examination.

METHODS

Ex vivo SLN mapping was applied to 131 prospectively recruited patients undergoing curative surgery for primary colon cancer. The SLNs were analyzed for the presence of tumor cells by routine histology and real-time RT-PCR quantitation of cytokeratin 20 (CK20) and mucin 2(MUC2) mRNA.

RESULTS

SLNs were identified in 125 (95%) of the 131 patients included.Routine histologic analysis of SLNs and other regional lymph nodes revealed LN metastases in 42 patients (N+), of which 29 (69%) had metastases detected in 1 or more SLNs (sensitivity, 69%; false negative rate, 31%).When analyzing the SLNs by quantitative RT-PCR, the sensitivity, compared with routine LN examination, was 37/42 (88%) for both the CK20 and the MUC2 mRNA markers. In addition, 46% and 27% of the patients' node negative by routine LN examination (N0) were positive for the CK20 and MUC2 mRNA markers, respectively, possibly reflecting the presence of occult tumor cells in their SLNs.

CONCLUSIONS

Quantitative RT-PCR analysis of SLNs identified N+ patients with high sensitivity and revealed a subgroup of N0 patients with potential occult LN disease.

Testing the Feasibility of Intra-Operative Sentinel Lymph Node Touch Imprint Cytology

INTRODUCTION

Sentinel lymph node biopsy is emerging as the new standard for axillary staging in breast cancer. Intra-operative assessment of the sentinel lymph nodes allows immediate completion of axillary dissection during the same anaesthetic. This project was a quality assurance practice to establish feasibility, time-to-report, as well as accuracy of performing intra-operative assessment of sentinel lymph nodes using touch imprint cytology in our centre.

PATIENTS AND METHODS

This prospective audit included 146 sentinel lymph nodes from 74 consecutive patients with invasive breast cancer. All patients underwent axillary sentinel lymph node biopsy using combined blue dye and radiocolloid technique. Results of intra-operative touch imprint cytology using haematoxylin and eosin staining were compared with the definitive histopathology results.

RESULTS

Mean time to report touch imprint cytology was 25.7 ± 6.4 min (range, 15–40 min). Histopathology demonstrated metastasis in 25 sentinel nodes from 17 (23%) patients. Intra-operative touch imprint cytology detected 15 nodes in 11 patients, giving a sensitivity of 60% (nodes) and 66.7% (patients) and specificity of 99.2% (nodes) and 98.2% (patients) based on the number of nodes and patients involved, respectively. Touch imprint cytology failed to show metastatic involvement in 10 nodes from 6 patients; of these, five nodes had micrometastasis (< 2 mm) and the other five had macrometastasis. One touch imprint cytology positive node contained isolated tumour cells only. Using intra-operative touch imprint cytology made a change in treatment of 11(14.9%) patients, and spared second axillary procedure in 7 (9.4%) patients.

CONCLUSIONS

Intra-operative sentinel lymph node assessment using touch imprint cytology is feasible within a busy NHS practice. We now offer touch imprint cytology to patients following appropriate counselling.