Pathology evaluation of sentinel lymph nodes in breast cancer: protocol recommendations and rationale

HistoMSC: Density and topology analysis for AI-based visual annotation of histopathology whole slide images

We introduce an end-to-end framework for the automated visual annotation of histopathology whole slide images. Our method integrates deep learning models to achieve precise localization and classification of cell nuclei with spatial data aggregation to extend classes of sparsely distributed nuclei across the entire slide. We introduce a novel and cost-effective approach to localization, leveraging a U-Net architecture and a ResNet-50 backbone. The performance is boosted through color normalization techniques, helping achieve robustness under color variations resulting from diverse scanners and staining reagents. The framework is complemented by a YOLO detection architecture, augmented with generative methods. For classification, we use context patches around each nucleus, fed to various deep architectures. Sparse nuclei-level annotations are then aggregated using kernel density estimation, followed by color-coding and isocontouring. This reduces visual clutter and provides per-pixel probabilities with respect to pathology taxonomies. Finally, we use Morse-Smale theory to generate abstract annotations, highlighting extrema in the density functions and potential spatial interactions in the form of abstract graphs. Thus, our visualization allows for exploration at scales ranging from individual nuclei to the macro-scale. We tested the effectiveness of our framework in an assessment by six pathologists using various neoplastic cases. Our results demonstrate the robustness and usefulness of the proposed framework in aiding histopathologists in their analysis and interpretation of whole slide images.

Indocyanine Green Near-Infrared Fluorescence-Guided Sentinel Lymph Node Biopsy in Colon Cancer

Background/Objectives: Indocyanine green (ICG)-guided near-infrared (NIR) fluorescence imaging represents a potentially advantageous approach for the identification of lymphatic drainage pathways. This study was undertaken to evaluate the efficacy of ICG-guided NIR fluorescence in mapping lymphatic drainage and facilitating sentinel lymph node biopsy (SLNB) in patients diagnosed with colon cancer. Methods: A prospective cohort of 30 consecutive patients with colon cancer undergoing surgical resection at our institution was enrolled in this study. Peritumoral injection of ICG was performed to facilitate intraoperative identification of sentinel lymph nodes (SLNs). Identified SLNs were marked and excised ex vivo following specimen retrieval. All the retrieved specimens were submitted for histopathological analysis using hematoxylin and eosin (H&E) staining. SLNs that were negative for metastatic disease upon H&E staining underwent further examination via immunohistochemistry (IHC). Results: Successful identification of SLNs was achieved in 83.33% of cases. The false positive rate was 6.6%, and the false negative rate was 8%, respectively. Atypical lymphatic drainage patterns were observed in 6.6% of the patients. Notably, the patients exhibiting atypical lymphatic drainage subsequently developed metastases during the follow-up period. Immunohistochemical analysis failed to detect micrometastases in SLNs that were initially deemed negative based on H&E staining. Conclusions: NIR-ICG fluorescence is a safe, reliable, and technically feasible method for performing SLNB in patients with colon cancer. Furthermore, this technique offers the potential for intraoperative identification of atypical lymphatic drainage pathways, which may have significant implications for determining the optimal extent of standard lymphadenectomy.

Evaluating Tumor Size to Ki67 Proliferation Index Ratio for Optimizing Surgical Axillary Treatment Decisions in Breast Cancer Patients

Despite advancements in breast cancer surgery, the decision-making process for axillary treatment remains complex, necessitating new predictors like the tumor size to Ki67 proliferation index ratio. Intraoperative examination of the sentinel lymph node is performed to reduce the risk of a secondary surgery. Several studies have demonstrated that even in the presence of moderate nodal involvement, local disease control can be achieved by omitting axillary lymph node dissection (ALND). The aim of our retrospective study is to compare patients subjected to sentinel lymph node biopsy (SNLB) with or without intraoperative evaluation. This study included patients with breast cancer who underwent breast-conserving surgery and SNLB. Of the 551 patients, 333 (60.4%) underwent an SNLB intraoperative evaluation (SLNB-IE), while 218 (39.6%) underwent sentinel lymph node dissection diagnostic evaluation (SLNB-DE). Our analysis revealed that the tumor size to Ki67 ratio is an independent predictive factor for axillary tumor burden, suggesting its utility in surgical decision-making. A secondary ALND was performed in 2 (0.6%) vs. 7 (2.8%), p = 0.032, and in 1 (0.4%) vs. 4 (2.1%), p = 0.171, excluding patients with T ≥ 2. Surgical time was significantly shorter (p > 0.001) in the SLNB-DE group. According to a multivariate analysis, lesion dimension (OR 1.678; 95%CI 1.019-2.145; WALD:7.588; p = 0.006) and the ratio of lesion dimension to the Ki67 proliferation index (OR 0.08; 95%CI 0.011-0.141; WALD:11.004 p = 0.001) were both predictive factors for a higher axillary tumor burden. A value of 0.425, which is the ratio of tumor dimension to the Ki67 proliferation index, was identified as a predictor of tumor burden in the axilla (sensitivity, 78%; specificity, 87.5%). Intraoperative evaluation of SNLB may be omitted but could be considered in potential candidates for cyclin inhibitor and cN0 therapy with a higher ratio of tumor dimension to the Ki67 proliferation index in order to avoid secondary surgery.

Feasibility of an indocyanine green-hyaluronic acid mixture (LuminoMark™) for targeting suspicious axillary lymph nodes in patients with breast cancer

PURPOSE

During breast cancer surgery, the use of dyes such as indigo carmine, methylene blue, or indocyanine green (ICG) for targeting axillary lymph nodes (ALNs) under ultrasound guidance can result in rapid diffusion, complicated tissue differentiation, and disruption of staining. LuminoMark™, a novel ICG-hyaluronic acid mixture, can provide real-time visualization and minimize dye spread, thereby ensuring a clear surgical field. The aim of our study was to evaluate the efficacy of LuminoMark™ for targeting ALNs in patients with breast cancer.

METHODS

A total of 13 patients with breast cancer (mean age 56.5 years; 92.3% female) and suspicious ALNs underwent targeted axillary surgery (TAS) with activated charcoal and LuminoMark™ injected into the LNs in the surgical field. The clinicopathological variables of the patients and diagnostic performance were assessed. The LNs injected with LuminoMark™ were examined for consistency with sentinel LNs (SLNs) and non-SLNs, as well as with charcoal-tattooed LNs.

RESULTS

The identification of SLNs took approximately 15.6 min from the start of skin incision, and it required 25.6 and 17.7 min, for charcoal-tattooed and LuminoMarkTM-illuminated LNs, respectively. The identification rate was 92.3% with charcoal and 100% with LuminoMark™. The concordance rate between LuminoMark™ illumination and SLNs was higher than that between charcoal tattooing and SLNs. The concordance rate between the two methods was 76.9% (n = 10). Three months after surgery, the charcoal tattoo remained visible on the skin; however, LuminoMark™ was not visible.

CONCLUSION

Although both methods demonstrated high detection rates, the rate was higher using LuminoMark™. As LuminoMark™ was administered directly into LNs, this improved the accuracy of identifying LNs.

The EORTC 22922/10925 trial investigating regional nodal irradiation in stage I-III breast cancer: Outcomes according to locoregional and systemic therapies

The EORTC 22922/10925 trial aimed to investigate the impact on overall survival (OS) of elective internal mammary and medial supraclavicular (IM-MS) radiation therapy (RT) in breast cancer stage I-III. Surgery for the primary tumour and axillary lymph nodes, chest wall RT, boost RT after whole breast RT in breast conserving therapy (BCT), RT to operated axilla, and systemic therapy were per physician's preference. The aim of the current analysis is to assess breast cancer outcomes according to different locoregional and systemic therapy used in the trial.

MATERIAL/METHODS

Data with a median follow-up of 15.7 years were extracted from the trial's case report forms. Kaplan-Meier curves of disease-free and OS and cumulative incidence curves of breast cancer events were produced. An exploratory analysis of the effect of the type of locoregional and systemic therapy on breast cancer outcomes was conducted using the Cox model or the Fine & Gray model accounting for competing risks, both models being adjusted for baseline patient and disease characteristics and treatment. The significance level was set at 5 %, 2-sided.

RESULTS

Of the 4,004 patients included, 625 (16%) did not receive any postoperative systemic therapy, 1,185 (30%) received endocrine therapy only, 994 (25%) chemotherapy only, and 1,200 (30%) both chemotherapy and endocrine therapy, without differences between the randomisation arms. Administration and type of therapy was associated with age, menopausal status, clinical T- and N-stage and ER status (p < 0.0001). Local control was better with mastectomy (with/without postmastectomy RT) as compared to BCT, but mastectomy was associated with more distant metastasis (DM) as first event. Similarly, DM as first event occurred more in the BCT group that received a boost as compared to no boost and in those who received RT to the lower axillary level. IM-MS RT reduced significantly regional recurrences and improved disease-free survival in a sensitivity stratified analysis. OS was worse with mastectomy as compared to BCT and with irradiation of the axilla but better with sentinel node dissection and adjuvant combined chemo and hormonal therapy.

CONCLUSION

Different components of therapy influenced the site of first event. IM-MS RT improved outcomes in different breast cancer outcomes were most probably related that the group were balanced due to the trial arms and stratification methods.

Value of sentinel node ultrastaging and pathologic techniques in tumoral detection

PURPOSE OF REVIEW

Sentinel lymph node assessment is an option for patients with clinically early-stage vulvar cancer, endometrial cancer, cervical cancer, and, more recently, ovarian cancer. However, although ultrastaging is mandatory as part of the node evaluation, universally accepted pathology protocols are lacking. This review focuses on the current evidence for the most relevant aspects of sentinel lymph node evaluation, as well as some controversial topics like frozen section or one-step nucleic acid amplification.

RECENT FINDINGS

The diagnostic accuracy of sentinel lymph node detection algorithms for patients with gynecologic neoplasms is high. However, the heterogeneity among the published studies and the absence of clear recommendations from most guidelines make it challenging to recommend one protocol over another. The minimum requirement from ultrastaging protocols (regarding the number of levels to be assessed, among others) to get the highest accuracy with a minor cost is unknown.

SUMMARY

Sentinel lymph node evaluation is now part of the surgical management for most early-stage gynecologic neoplasms. However, a universally accepted ultrastaging pathology protocol is lacking in literature and clinical practice. This gap requires significant effort from the gynecologic oncology and pathology community to be closed and then to allow advancements in surgical management for early-stage gynecologic tumors to go forward.

A novel nomogram and survival analysis for different lymph node status in breast cancer based on the SEER database

INTRODUCTION

The axillary lymph node status (ALNS) and internal mammary lymph nodes (IMLN) expression associated with breast cancer are closely linked to prognosis. This study aimed to establish a nomogram to predict survival at 3, 5, and 10 years in patients with various lymph node statuses.

METHODS

We obtained data from patients with breast cancer between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER database). Chi-square analysis was performed to test for differences in the pathological characteristics of the groups, and Kaplan-Meier analysis and the log-rank test were used to plot and compare the correlation between overall survival (OS) and breast cancer specific survival (BCSS). The log-rank test was used for the univariate analysis, and statistically significant characteristics were included in the multivariate and Cox regression analyses. Finally, Independent factor identification was included in constructing the nomogram using R studio 4.2.0; area under curve (AUC) values were calculated, and receiver operating characteristic (ROC) curve, calibration, and decision curve analysis (DCA) curves were plotted for evaluation.

RESULTS

A total of 279,078 patients were enrolled and analysed, demonstrating that the isolated tumour cells (ITC) group had clinicopathological characteristics similar to those of micrometastases (Mic). Multivariate analysis was performed to identify each subgroup's independent risk factors and construct a nomogram. The AUC values were 74.7 (95% CI 73.6-75.8), 72.8 (95% CI 71.9-73.8), and 71.2 (95% CI 70.2-72.2) for 3-, 5-, and 10-year OS, respectively, and 82.2 (95% CI 80.9-83.6), 80.1 (95% CI 79.0-81.2), and 75.5 (95% CI 74.3-76.8) for BCSS in overall breast cancer cases, respectively. AUC values for 3-, 5-, and 10-year OS in the ITC group were 64.8 (95% CI 56.5-73.2), 67.7 (95% CI 62.0-73.4), and 65.4 (95% CI 60.0-70.7), respectively. For those in the Mic group, AUC values for 3-, 5-, and 10-year OS were 72.9 (95% CI 70.7-75.1), 72.4 (95% CI 70.6-74.1), and 71.3 (95% CI 69.6-73.1), respectively, and AUC values for BCSS were 77.8 (95% CI 74.9-80.7), 75.7 (95% CI 73.5-77.9), and 70.3 (95% CI 68.0-72.6), respectively. In the IMLN group, AUC values for 3-, 5-, and 10-year OS were 75.2 (95% CI 71.7-78.7), 73.4 (95% CI 70.0-76.8), and 74.0 (95% CI 69.6-78.5), respectively, and AUC values for BCSS were 76.6 (95% CI 73.0-80.3), 74.1 (95% CI 70.5-77.7), and 74.7 (95% CI 69.8-79.5), respectively. The ROC, calibration, and DCA curves verified that the nomogram had better predictability and benefits.

CONCLUSION

This study is the first to investigate the predictive value of different axillary lymph node statuses and internal mammary lymph node metastases in breast cancer, providing clinicians with additional aid in treatment decisions.

Introducing effective genes in lymph node metastasis of breast cancer patients using SHAP values based on the mRNA expression data

OBJECTIVE

Breast cancer, a global concern predominantly impacting women, poses a significant threat when not identified early. While survival rates for breast cancer patients are typically favorable, the emergence of regional metastases markedly diminishes survival prospects. Detecting metastases and comprehending their molecular underpinnings are crucial for tailoring effective treatments and improving patient survival outcomes.

METHODS

Various artificial intelligence methods and techniques were employed in this study to achieve accurate outcomes. Initially, the data was organized and underwent hold-out cross-validation, data cleaning, and normalization. Subsequently, feature selection was conducted using ANOVA and binary Particle Swarm Optimization (PSO). During the analysis phase, the discriminative power of the selected features was evaluated using machine learning classification algorithms. Finally, the selected features were considered, and the SHAP algorithm was utilized to identify the most significant features for enhancing the decoding of dominant molecular mechanisms in lymph node metastases.

RESULTS

In this study, five main steps were followed for the analysis of mRNA expression data: reading, preprocessing, feature selection, classification, and SHAP algorithm. The RF classifier utilized the candidate mRNAs to differentiate between negative and positive categories with an accuracy of 61% and an AUC of 0.6. During the SHAP process, intriguing relationships between the selected mRNAs and positive/negative lymph node status were discovered. The results indicate that GDF5, BAHCC1, LCN2, FGF14-AS2, and IDH2 are among the top five most impactful mRNAs based on their SHAP values.

CONCLUSION

The prominent identified mRNAs including GDF5, BAHCC1, LCN2, FGF14-AS2, and IDH2, are implicated in lymph node metastasis. This study holds promise in elucidating a thorough insight into key candidate genes that could significantly impact the early detection and tailored therapeutic strategies for lymph node metastasis in patients with breast cancer.

Establishing guidelines for sentinel lymph node ultrastaging in endometrial cancer

BACKGROUND

Many sentinel lymph node (SLN) ultrastaging protocols for endometrial cancer exist, but there is no consensus method.

OBJECTIVE

This study aims to develop guidelines for size criteria in SLN evaluation for endometrial cancer, to determine whether a single cytokeratin AE1:AE3 immunohistochemical slide provides sufficient data for diagnosis, and to compare cost efficiency between current and limited ultrastaging protocols at a large tertiary care institution.

METHODS

Our current SLN ultrastaging protocol consists of cutting two adjacent paraffin block sections at two levels (L1 and L2), 50 μm apart, with two slides at each level stained with hematoxylin and eosin and cytokeratin AE1:AE3 immunohistochemistry. We retrospectively reviewed digitized L1 and L2 slides of all positive ultrastaged SLNs from patients treated for endometrial cancer between January 2013 and January 2020. SLN diagnosis was defined by measuring the largest cluster of contiguous tumor cells in a single cross section: macrometastasis (>2.0 mm), micrometastasis (>0.2 to ≤2.0 mm or >200 cells), or isolated tumor cells (≤0.2 mm or ≤200 cells). Concordance between L1 and L2 results was evaluated. Cost efficiency between current (two immunohistochemical slides per block) and proposed limited (one immunohistochemical slide per block) protocols was compared.

RESULTS

Digitized slides of 147 positive SLNs from 109 patients were reviewed; 4.1% of SLNs were reclassified based on refined size criteria. Complete concordance between L1 and L2 interpretations was seen in 91.8% of SLNs. A false-negative rate of 0%-0.9% in detecting micrometastasis and macrometastasis using a limited protocol was observed. Estimated charge-level savings of a limited protocol were 50% per patient.

CONCLUSION

High diagnostic accuracy in SLN interpretation may be achieved using a limited ultrastaging protocol of one immunohistochemical slide per block and linear measurement of the largest cluster of contiguous tumor cells. Implementation of the proposed limited ultrastaging protocol may result in laboratory cost savings with minimal impact on health outcomes.

The role of lymph nodes and their drainage in canine mammary gland tumours: Systematic review

Mammary gland tumours are the most common neoplasms in intact bitches. Over the last decades, veterinary oncology has evolved in detecting and determining the lymph nodes to be removed in these patients for an accurate staging and prognosis, as well as to achieve better disease control and higher overall survival time. Our objective was to describe recent advances related to lymphatic drainage in bitches with mammary gland tumours, focusing on surgery, diagnosis, and prognosis. Through a systematic review using PubMed as the database, a thorough multi-step search reduced 316 studies to 30 for analysis. Vital dyes appear to be crucial in reducing the overall surgery time through transoperative staining of the lymph nodes. Imaging contrasts provide information regarding specific tumour drainage; however, there is still little evidence for their use. The axillary and superficial inguinal lymph nodes are well-established as regional lymph nodes of the cranial and caudal mammary glands. In sequence, accessory axillary, medial iliac, popliteal, and sternal lymph nodes should receive attention if they demonstrate contrast drainage, even considering that the literature has not shown a relationship between drainage and metastasis in these cases. In conclusion, recent studies have provided us with more support in regional lymph node excision regarding the TNM staging system. Studies are highly heterogeneous and method comparisons do not fit due to the non-uniformity of samples, materials, and procedures. We suggest further studies with a larger sample size, complete follow-up of patients, contrast use, and lymph node morphological and immunohistochemical analysis.

Pragmatic guide to the macroscopic evaluation of breast specimens

The pathological assessment of a breast surgical specimen starts with macroscopic evaluation, arguably one of the most critical steps, as only a small percentage of the tissue is examined microscopically. To properly evaluate and select tissue sections from breast specimens, it is essential to correlate radiological findings, prior biopsies, procedures and treatment with the gross findings. Owing to its fatty nature, breast tissue requires special attention for proper fixation to ensure appropriate microscopic evaluation and performance of ancillary studies. In addition, knowledge of the information necessary for patient management will ensure that these data are collected during the macroscopic evaluation, and appropriate sections are taken to obtain the information needed from the microscopic evaluation. Herein, we present a review of the macroscopic evaluation of different breast specimen types, including processing requirements, challenges and recommendations.

Update on Sentinel Lymph Node Methods and Pathology in Breast Cancer

Breast cancer stands out as the most commonly diagnosed cancer among women globally. Precise lymph node staging holds critical significance for both predicting outcomes in early-stage disease and formulating effective treatment strategies to control regional disease progression in breast cancer patients. No imaging technique possesses sufficient accuracy to identify lymph node metastases in the early stages (I or II) of primary breast cancer. However, the sentinel node procedure emerges as a valuable approach for identifying metastatic axillary nodes. The sentinel lymph node is the hypothetical first lymph node or group of nodes draining a cancer. In case of established cancerous dissemination, it is postulated that the sentinel lymph nodes are the target organs primarily reached by metastasizing cancer cells from the tumor. The utilization of the sentinel node technique has brought about changes in the assessment of lymph nodes. It involves evaluating the sentinel node during surgery, enabling prompt lymph node dissection when the sentinel node procedure is positive. Additionally, histological ultra-stratification is employed to uncover occult metastases. This review aims to provide an update of this valuable technique, with focus on the practical aspects of the procedure and the different histological protocols of sentinel node evaluation in breast cancer.

Synthesis, and In-silico Studies of Indole-chalcone Derivatives Targeting Estrogen Receptor Alpha (ER-α) for Breast Cancer

BACKGROUND

Breast cancer is the prominent reason of death in women worldwide, and the cases are increasing day by day. There are many FDA-approved drugs for treating breast cancer. Due to drug resistance, and problems in selectivity, there is a need to develop more effective agents with few side effects. Indole derivatives have demonstrated significant pharmacological potential as anti-breast cancer agents. Further, chalcone derivatives incorporating heterocyclic scaffolds play a significant role in medicine. Indole-chalcone-based compounds offer the potential for improved biological activity and enhanced drug-like properties. It prompted us to explore the synthesis of Indole-Chalcone derivatives targeting estrogen receptor alpha (ER-α) to discover potent anti-breast cancer agents.

OBJECTIVES

To synthesize indole-chalcone derivatives and study their binding interactions for ER-α protein by molecular docking for breast cancer treatment.

METHODS

In this study, indole-chalcone derivatives have been synthesized using conventional heating. With the help of Schrodinger software, molecular interaction as well as ADME (Adsorption, Distribution, Metabolism, and Excretion) studies of the compounds were conducted.

RESULTS

Among all the synthesized compounds, four compounds (1, 2, 3, and 4) showed better docking scores (-10.24 kcal/mol, -10.15 kcal/mol, -9.40 kcal/mol, -9.29 kcal/mol, respectively) than the standard tamoxifen (-8.43 kcal/mol).

CONCLUSION

From In-silico studies, we can conclude that four compounds from the synthesized series fit into the active site of ER-α. ADME properties of synthesized derivatives were found in the acceptable range. In the future, these compounds can be further explored for biological activity.

Updates in the Use of Immunohistochemical Stains in Breast and Gynecologic Pathology

CONTEXT.—

The use of immunohistochemical stains in breast and gynecologic pathology has become increasingly complex, with various diagnostic, prognostic, and predictive applications.

OBJECTIVE.—

To provide an update and review of immunohistochemical stains used in the practice of breast and gynecologic pathology. Established and new entities are reviewed, with descriptions of histomorphology and immunohistochemical staining patterns and discussion of interpretive pitfalls.

DATA SOURCES.—

Data were obtained from review of the English-language literature and firsthand experience of the authors in breast and gynecologic pathology.

CONCLUSIONS.—

Many entities in breast and gynecologic pathology benefit from evaluation with various immunohistochemical stains. These studies not only aid in the diagnosis and staging of tumors but also can provide prognostic and predictive information. Updated guidelines for recommended ancillary studies such as mismatch repair, p53, and human epidermal growth factor receptor 2 (HER2) studies in endometrium, as well as estrogen and progesterone receptors and HER2 in breast, are discussed. Finally, the use and interpretation of established and novel immunohistochemical stains are discussed in various breast and gynecologic malignancies.

Omission of axillary lymph node dissection in breast cancer patients with micrometastasis or isolated tumor cells in sentinel lymph nodes: a 12-year experience in a tertiary breast unit

INTRODUCTION

After the IBCSG 23-01 trial, our breast center no longer performed axillary lymph node dissection (ALND) after detection of isolated tumor cells (ITC) or micrometastasis in the sentinel lymph nodes (SLN). A recent study suggested that up to half of the patients with micrometastasis in the SLN could benefit from ALND in terms of disease-free survival (DFS) and overall survival (OS).

METHODS

This retrospective, unicentric, study analyzed 261 consecutive cT1-3 cN0 breast cancer patients with ITC or micrometastasis in their SLN. Primary objective was comparison of ALND vs. SLN biopsy (SLNB) with regard to DFS and OS. Secondary objectives included analysis of factors associated with an increased rate of locoregional recurrence (LRR), distant metastasis (DM) and metachronous contralateral breast cancer (MCBC).

RESULTS

DFS events occurred in 19 patients (7.3%) and 14 patients died (5.4%). Median follow-up time was 78 months. 251 patients (96.2%) had micrometastasis in their SLN. There was no difference in the OS or DFS of ALND vs. SLNB patients. History of previous contralateral breast cancer and WBI were associated with an increased and decreased rate of LRR, respectively. Larger tumor size was associated with an increased rate of DM. Non-ductal histological types were associated with an increased rate of MCBC.

DISCUSSION

Avoiding ALND may be safe in pN1mi/pN0(i+) patients. Besides, we strongly encourage clinicians to develop their own follow-up protocols based on the best available evidence, to rapidly identify and treat breast cancer recurrence.

Discordance Between Conventional and Detailed Lymph Node Analysis in Resected, Node-negative Pancreatic or Ampullary Adenocarcinomas and Association With Adverse Survival Outcomes: A Single-institution Analysis

OBJECTIVE

To assess the frequency of occult metastases (OM) in patients with resected pancreatic ductal adenocarcinoma (PDAC) or ampullary adenocarcinoma (AA) discovered on detailed pathologic examination on lymph nodes (LNs) previously considered negative by conventional analysis and to examine the association between OM and overall survival (OS).

BACKGROUND

Poor prognosis of patients with no pathologic evidence of LN metastases may be due to OM that is not detected on conventional LN analysis.

METHODS

Patients with LN-negative resected PDAC or AA (2010-2020) were identified from our institutional database. Original hematoxylin and eosin ( H and E ) slides were reanalyzed. In addition, selected LN were analyzed by H and E (3 sections/LN) and pan-cytokeratin (AE1-AE3/PCK26) immunohistochemistry.

RESULTS

A total of 598 LNs from 74 LN-negative patients were reexamined. Nineteen patients (25.7%) had OM; 9 (47.4%) were found with immunohistochemistry but not on H and E . The number of positive LNs ranged from 1 to 3. No clinicodemographic, pathologic, or treatment-related factors were associated with OM. On conventional LN analysis, 3/19 patients (15.8%) had stage IA, 9/34 (26.5%) had stage IB, and 7/19 (36.8%) had stage IIA. On detailed LN analysis, 11/19 patients (57.9%) were upstaged to IIB, whereas 8/19 (42.1%) had isolated tumor cells only (N0i+). OM was associated with shorter OS (median OS: 22.3 vs 50.5 months; hazard ratio=3.95, 95% CI: 1.58-9.86).

CONCLUSIONS

There is a 26% discordance rate between conventional and detailed LN pathologic analysis in resected PDAC and AA. The presence of OM is associated with shorter OS.

Artificial Intelligence-Aided Diagnosis of Breast Cancer Lymph Node Metastasis on Histologic Slides in a Digital Workflow

Identifying lymph node (LN) metastasis in invasive breast carcinoma can be tedious and time-consuming. We investigated an artificial intelligence (AI) algorithm to detect LN metastasis by screening hematoxylin and eosin (H&E) slides in a clinical digital workflow. The study included 2 sentinel LN (SLN) cohorts (a validation cohort with 234 SLNs and a consensus cohort with 102 SLNs) and 1 nonsentinel LN cohort (258 LNs enriched with lobular carcinoma and postneoadjuvant therapy cases). All H&E slides were scanned into whole slide images in a clinical digital workflow, and whole slide images were automatically batch-analyzed using the Visiopharm Integrator System (VIS) metastasis AI algorithm. For the SLN validation cohort, the VIS metastasis AI algorithm detected all 46 metastases, including 19 macrometastases, 26 micrometastases, and 1 with isolated tumor cells with a sensitivity of 100%, specificity of 41.5%, positive predictive value of 29.5%, and negative predictive value (NPV) of 100%. The false positivity was caused by histiocytes (52.7%), crushed lymphocytes (18.2%), and others (29.1%), which were readily recognized during pathologists' reviews. For the SLN consensus cohort, 3 pathologists examined all VIS AI annotated H&E slides and cytokeratin immunohistochemistry slides with similar average concordance rates (99% for both modalities). However, the average time consumed by pathologists using VIS AI annotated slides was significantly less than using immunohistochemistry slides (0.6 vs 1.0 minutes, P = .0377). For the nonsentinel LN cohort, the AI algorithm detected all 81 metastases, including 23 from lobular carcinoma and 31 from postneoadjuvant chemotherapy cases, with a sensitivity of 100%, specificity of 78.5%, positive predictive value of 68.1%, and NPV of 100%. The VIS AI algorithm showed perfect sensitivity and NPV in detecting LN metastasis and less time consumed, suggesting its potential utility as a screening modality in routine clinical digital pathology workflow to improve efficiency.

Systematic review and meta-analysis of the prognostic impact of lymph node micrometastasis and isolated tumour cells in patients with stage I-IIIA non-small cell lung cancer

Lymph node micrometastases could be one of the reasons for the high recurrence rate after complete surgical resection in stage I-IIIA non-small cell lung cancer (NSCLC). The standard evaluation of a single haematoxylin and eosin (H&E) slide of a paraffin-embedded section of a lymph node is insufficient for the detection of micrometastases, and there is a need for additional histopathological evaluation. The association of lymph node micrometastases with survival remains as yet unresolved. The aim of this systematic review and meta-analysis is to investigate if lymph node micrometastases and isolated tumour cells in patients with stage I-IIIA NSCLC, detected with multiple sectioning and/or immunohistochemistry (IHC) and/or reverse transcriptase polymerase chain reaction (RT-PCR), are associated with overall survival (OS) and disease-free survival (DFS) after surgical resection. We performed a meta-analysis of time-to-event outcomes based on 15 articles using ancillary techniques to detect micrometastases. We extracted the OS and DFS every 3-6 months after surgery, for patients with and without occult lymph node micrometastasis, from the survival curves published in each article. These data were used to reconstruct OS and DFS for 'micrometastasis' and 'no micrometastasis' groups. Based on all included studies that used IHC, serial sectioning, or RT-PCR, we found a 5-year OS of 55% (micrometastasis) vs. 75% (no micrometastasis), and a 5-year DFS of 53% (micrometastasis) vs. 75% (no micrometastasis). Patients with stage I-IIIA NSCLC with lymph node micrometastases detected by ancillary histopathological and molecular techniques have a significantly poorer OS and DFS compared to patients without lymph node micrometastases.

The Risk of Recurrence in Endometrial Cancer Patients with Low-Volume Metastasis in the Sentinel Lymph Nodes: A Retrospective Multi-Institutional Study

The aim of this study was to assess the impact of low-volume metastasis (LVM) on disease-free survival (DFS) in women with apparent early-stage endometrial cancer (EC) who underwent sentinel lymph node (SLN) mapping. Patients with pre-operative early-stage EC were retrospectively collected from an international collaboration including 13 referring institutions. A total of 1428 patients were included in this analysis. One hundred and eighty-six patients (13%) had lymph node involvement. Fifty-nine percent of positive SLN exhibited micrometastases, 26.9% micrometastases, and 14% isolated tumor cells. Seventeen patients with positive lymph nodes did not receive any adjuvant therapy. At a median follow-up of 33.3 months, the disease had recurred in 114 women (8%). Patients with micrometastases in the lymph nodes had a worse prognosis of disease-free survival compared to patients with negative nodes or LVM. The rate of recurrence was significantly higher for women with micrometastases than those with low-volume metastases (HR = 2.61; p = 0.01). The administration of adjuvant treatment in patients with LVM, without uterine risk factors, remains a matter of debate and requires further evaluation.

Feasibility of Breast Cancer Metastasis Assessment of Ex Vivo Sentinel Lymph Nodes through a p-H&E Optical Coherence Microscopic Imaging System

Frozen-sectioned hematoxylin-eosin (H&E) image evaluation is the current method for intraoperative breast cancer metastasis assessment through ex vivo sentinel lymph nodes (SLNs). After frozen sectioning, the sliced fatty region of the frozen-sectioned specimen is easily dropped because of different freezing points for fatty tissues and other tissues. Optical-sectioned H&E images provide a nondestructive method for obtaining the insight en face image near the attached surface of the dissected specimen, preventing the freezing problem of fatty tissue. Specimens from 29 patients at Wanfang Hospital were collected after excision and were analyzed at the pathology laboratory, and a fluorescence-in-built optical coherence microscopic imaging system (OCMIS) was then used to visualize the pseudo-H&E (p-H&E) images of the SLNs for intraoperative breast cancer metastasis assessment, and the specificity, sensitivity, and accuracy were 100%, 88.9%, and 98.8% (n = 83), respectively. Compared with gold-standard paraffin-sectioned H&E images, the specificity, sensitivity, and accuracy obtained with the frozen-sectioned H&E images (n = 85) of the specimens were the same as those obtained with the p-H&E images (n = 95). Thus, OCMIS is a useful noninvasive image-assisted tool for breast cancer metastasis assessment based on SLN images.

Reporting of Surgically Removed Lymph Nodes for Breast Tumors: Recommendations From the International Collaboration on Cancer Reporting

CONTEXT.—

The International Collaboration on Cancer Reporting (ICCR), supported by major pathology and cancer organizations, aims at the standardization of evidence-based pathology reporting of different types of cancers, with the inclusion of all parameters deemed to be relevant for best patient care and future data collection. Lymph node metastasis is one of the most important prognostic factors in breast cancer.

OBJECTIVE.—

To produce a histopathology reporting guide by a panel of recognized experts from the fields of pathology and surgery with elements deemed to be core (required) and noncore (recommended) to report when assessing regional lymph nodes of patients with breast cancer.

DATA SOURCES.—

Published literature, previous guidelines/recommendations, and current cancer staging principles were the basis of the data set drafted by the expert panel. This was discussed in a series of teleconferences and email communications. The draft data set was then made available for public consultation through the ICCR Web site. After this consultation and ICCR ratification, the data set was finalized.

CONCLUSIONS.—

The ICCR has published a data set for the reporting of surgically removed lymph nodes (including sentinel lymph node biopsy, axillary lymph node dissection, targeted axillary surgery, and lymph node sampling specimens) for breast tumors. This is part of a series of 4 ICCR breast cancer-related data sets. It includes 10 core elements along with 2 noncore elements. This should allow for synoptic reporting, which is more precise, uniform, and complete than nonsynoptic reporting, and leads to improved patient outcomes.

Pathological processing of sentinel lymph nodes in endometrial carcinoma - routine aspects of grossing, ultra-staging, and surgico-pathological parameters in a series of 833 lymph nodes

Sentinel lymph nodes are widely accepted in the treatment of endometrial carcinoma. Whereas surgical aspects are well studied, the pathological work-up in terms of grossing, frozen section, and the so-called ultra-staging is still a matter of debate. This results in conflicting national or center-based recommendations. In a series of consecutive 833 sentinel lymph nodes from 206 patients in endometrial carcinomas, we compared three different grossing techniques and the use of frozen section in terms of anatomy, detection rates, and survival. In total, 42 macro-metastases, 6 micro-metastases, and 25 nodes with isolated tumor cells were found. Lymph nodes affected at least with micro-metastasis were about 0.5cm enlarged. Detection rates in lamellation technique increased with a step of 5.9% to 8.3% in comparison to bi-valved or complete embedding. The lamellation technique presented with a slight beneficial prognosis in pN0 subgroup (OS, p=0.05), which besides size effects might be attributed to trimming loss. In frozen section, this effect was less pronounced than expected (OS, p=0.56). Ultra-staging only revealed additional micro-metastases and isolated tumor cells. Exclusively, macro-metastases showed poor survival (p<0.001). In multivariate analysis, T-stage, subtype, and lympho-vascular invasion status outperformed this staging parameter significantly. Grossing of sentinel lymph nodes is the most essential step with evidence to prefer lamellation in 2 mm steps. Step sectioning should consider widely spaced protocols to exclude macro-metastases. Frozen sections might add value to the intra-operative assessment of endometrial carcinoma in selected cases. The excellent biological behavior of cases with isolated tumor cells might question the routine application of pan-cytokeratin as ultra-staging method.

One-Step Nucleic Acid Amplification System in Comparison to the Intraoperative Frozen Section and Definitive Histological Examination Among Breast Cancer Patients: A Retrospective Survival Study

Simple Summary

Implementing intraoperative assessment of sentinel lymph nodes by one-step nucleic acid amplification in early breast cancer can reduce the surgical burden to the patient and the costs to the health system. However, only limited data are available in terms of long-term disease-free survival and overall survival. Therefore, this study aims to compare disease-free survival and overall survival between one-step nucleic acid amplification, frozen section, and definitive histology. These results could impact the healthcare community, adding further proof to the body of evidence supporting the broader adoption of this innovative technology that enables a safe reduction in patient surgical burden and healthcare costs.

Background

The one-step nucleic acid amplification (OSNA) system is a novel molecular technique, which consents to quick intraoperative detection of sentinel lymph node metastases by the amplification of cytokeratin 19 mRNA. Our study aims to evaluate the OSNA method in comparison with frozen section (FS) and definitive histological examination of the sentinel lymph node biopsy among early breast cancer patients considering disease-free survival (DFS) and overall survival (OS).

Methods

In this study, we included all women who underwent sentinel lymph node biopsy (SLNB) for breast cancers classified as TNM stage I and II in our center between January 2005 and January 2017, and the follow-up was collected up to January 2019. We divided patients among three groups based on SLNB evaluation: definitive histological examination, intra-operative FS, or OSNA.

Results

We included 2412 SLNBs: 727 by definitive histological examination, 697 by FS, and 988 by OSNA. Isolated tumor cells were found in 2.32% of cases, micrometastasis in 9.12%, and macrometastases in 13.64%. Surgical procedure duration was significantly shorter in OSNA than in FS (42.1 minutes ±5.1 vs. 70.1 minutes ±10.5, p <0.05). No significant differences have been observed among the three groups regarding OS, DSF, cumulative local, or distant metastases. In particular 5-year DFS was 96.38% in definitive histology (95% C.I. 95.02-97.75%), 96.37% in FS (95% C.I. 94.98-97.78%), and 96.51% in OSNA group (95% C.I. 95.32-97.72%).

Conclusions

No difference in OS and DFS was found comparing OSNA, FS, and definitive histology. Furthermore, reduced operative time was found in the OSNA group.

Longitudinal lymph node step-sectioning for the identification of metastatic disease in canine mast cell tumor

Lymph node (LN) metastasis in canine mast cell tumor (MCT) can affect prognosis and postsurgical treatment recommendations; however, routine histological single-section examination may underestimate the incidence of metastases. This prospective study aimed at determining whether longitudinal step-sectioning of the entire LN allows for a more reliable detection of metastases. Dogs with MCT undergoing resection of the primary tumor and regional lymphadenectomy were enrolled. Formalin-fixed LNs were bisected longitudinally, both halves were embedded in paraffin and histological sections prepared at 200 μm steps. The nodal mast cells were classified according to the Weishaar classification. First-section evaluation (FSE; ie, examination of the first section obtained from the blocks) and whole LN step-section evaluation (SSE) were compared. Fifty-eight LNs were included. The median number of sections per LN was 6 (range, 3–28). FSE with toluidine blue (TB) revealed 27 (47%) nonmetastatic (HN0), 14 (24%) premetastatic (HN1), 9 (15%) early metastatic (HN2), and 8 (14%) overtly metastatic (HN3) LNs. SSE with TB resulted in upgrading the LN status in 2 cases (HN2 to HN3; HN0 to HN1). Evaluation of the first section plus an additional step-section resulted in 100% accuracy. Compared with SSE with TB, the accuracy of FSE with HE was 98% for HN3 LNs and 74% for HN2 LNs. FSE appears to reliably allow for the detection of LN metastasis in MCT, although examination of a further parallel section at a 200 μm step may increase the accuracy. A metachromatic stain is recommended for the identification of early metastases.

Artificial intelligence applied to breast pathology

The convergence of digital pathology and computer vision is increasingly enabling computers to perform tasks performed by humans. As a result, artificial intelligence (AI) is having an astoundingly positive effect on the field of pathology, including breast pathology. Research using machine learning and the development of algorithms that learn patterns from labeled digital data based on "deep learning" neural networks and feature-engineered approaches to analyze histology images have recently provided promising results. Thus far, image analysis and more complex AI-based tools have demonstrated excellent success performing tasks such as the quantification of breast biomarkers and Ki67, mitosis detection, lymph node metastasis recognition, tissue segmentation for diagnosing breast carcinoma, prognostication, computational assessment of tumor-infiltrating lymphocytes, and prediction of molecular expression as well as treatment response and benefit of therapy from routine H&E images. This review critically examines the literature regarding these applications of AI in the area of breast pathology.

How Do Pathologists in Academic Institutions Across the United States and Canada Evaluate Sentinel Lymph Nodes in Breast Cancer? A Practice Survey

OBJECTIVES

There are little data on how changes in the clinical management of axillary lymph nodes in breast cancer have influenced pathologist evaluation of sentinel lymph nodes.

METHODS

A 14-question survey was sent to Canadian and US breast pathologists at academic institutions (AIs).

RESULTS

Pathologists from 23 AIs responded. Intraoperative evaluation (IOE) is performed for selected cases in 9 AIs, for almost all in 10, and not performed in 4. Thirteen use frozen sections (FSs) alone. During IOE, perinodal fat is completely trimmed in 8, not trimmed in 9, and variable in 2. For FS, in 12 the entire node is submitted at 2-mm intervals. Preferred plane of sectioning is parallel to the long axis in 8 and perpendicular in 12. In 11, a single H&E slide is obtained, whereas 12 opt for multiple levels. In 11, cytokeratin is obtained if necessary, and immunostains are routine in 10. Thirteen consider tumor cells in pericapsular lymphatics as lymphovascular invasion (LVI), and 10 consider it isolated tumor cells (ITCs).

CONCLUSIONS

There is dichotomy in practice with near-equal support for routine vs case-by-case multilevel/immunostain evaluation, perpendicular vs parallel sectioning, complete vs incomplete fat removal, and tumor in pericapsular lymphatics as LVI vs ITCs.

A retrospective study on prophylactic regional lymphadenectomy versus nodal observation only in the management of dogs with stage I, completely resected, low-grade cutaneous mast cell tumors

BACKGROUND

While lymphadenectomy of metastatic lymph nodes (LNs) has been associated with improved outcome, the clinical utility of prophylactic lymphadenectomy in dogs with stage I cutaneous mast cell tumors (cMCTs) remains a controversial topic. To assess the therapeutic role of lymphadenectomy of uninvolved regional LNs, the long-term outcome of cMCT-bearing dogs with cytologically negative and surgically unresected regional LNs (observation only, OO) was compared with that of dogs with surgically resected and histologically negative regional LNs (prophylactic regional lymphadenectomy, PRL).

RESULTS

A retrospective analysis of 64 dogs with a low-grade, completely resected stage I cMCT was performed: 35 (54.7%) dogs were subjected to OO and 29 (45.3%) underwent PRL. Dogs were monitored for a median of 813 and 763 days in the OO group and PRL group, respectively. The number of dogs undergoing MCT progression was significantly higher in the OO group (P = 0.028) and curve comparison revealed a tendency to a better time to progression in the PRL group (P = 0.058). No significant difference in survival time (P = 0.294) was observed between dogs in the OO and PRL groups.

CONCLUSIONS

Our results showed that lack of immediate lymphadenectomy was associated with a higher risk for tumor progression. This preliminary judgement, reinforced by the findings that lymphadenectomy was well tolerated in all cases, and that histopathology provides the definitive assessment of the nodal pathological status, may suggest that prophylactic lymphadenectomy is indicated in the management of stage I MCTs. Larger prospective studies are warranted for generating clinical evidence of this latter hypothesis.

Diagnostic Performance of Indocyanine Green Plus Methylene Blue Versus Radioisotope Plus Methylene Blue Dye Method for Sentinel Lymph Node Biopsy in Node-Negative Early Breast Cancer

PURPOSE

Sentinel lymph node biopsy (SLNB) by dual-dye method (radioisotope plus blue) is the gold standard for axillary staging in patients with breast cancer, but in developing countries, logistic issues and financial constraint play a vital role. Recently, indocyanine green (ICG) has emerged as an alternative to radioisotope (technetium-99 [Tc-99]) for SLNB in breast cancer. This study compared the diagnostic performance of Tc-99 plus methylene blue (MB) dye versus ICG + MB dye SLNB.

METHODS

Two hundred seven patients with early breast cancer (T1-3N0) were included in the study from 2017 to 2019. SLNB was done either with Tc-99 + MB or with ICG + MB as per availability of radioisotope. SLN identification rate (IR), SLN positivity rate, and metastatic SLN counts were compared between the 2 groups.

RESULTS

IR was 199 (96%) of 207. IR was 95% in Tc-99 + MB compared with 97% with ICG + MB. The mean number of SLNs identified were 3.17 (standard deviation [SD], 1.84), with > 1 SLN identified in 87% patients by Tc-99 + MB. SLN was positive in 31.3% of patients with a metastatic SLN count of 0.37 (SD, 0.76). With ICG + MB, the number of SLNs was 2.73 (SD, 1.55), with > 1 SLN identified in 79% of patients. Twenty-eight percent of patients had positive SLNs, with a metastatic SLN count of 0.41 (SD, 0.77). A sharp decline in the availability of Tc-99 was observed, with 58% of patients in 2014 and only 12% of patients in 2018.

CONCLUSION

ICG is equivalent to Tc-99 for SLNB in early breast cancer and has a good potential to be adopted by surgeons in resource-constrained setups.

Sentinel lymph node assessment in breast cancer-an update on current recommendations

Sentinel lymph node biopsy (SLNB) has become the preferred method of surgical pathological nodal staging of early breast cancer by the end of the nineties. As the most likely sites of metastasis, the SLNs allow a more precise staging, and indeed gross sectioning, step sectioning, immunohistochemistry, and molecular staging methods have been used to disclose metastatic involvement of these lymph nodes. This review summarizes the backgrounds of SLNB, trends in related surgery and pathology. It also gives an insight into European National recommendations related to SLN and divergent daily practices in European pathology departments, on the basis of replies to questionnaires from 84 pathologists from 38 European countries. The questionnaires revealed the post-neoadjuvant setting as an area where a significant minority of pathologists report less confidence in classifying residual nodal involvement into TNM categories. The review also summarizes the neoadjuvant therapy-related aspects of SLNB.

Prognostic value of extranodal extension in axillary lymph node-positive breast cancer

Several studies have demonstrated that extranodal extension (ENE) is associated with prognosis in breast cancer. Whether this association should be described in pathological reports warrants further investigation. In this research, we evaluated the predictive value of ENE in axillary lymph nodes (ALNs) in invasive breast cancer and explored the feasibility of employing ENE to predict clinicopathological features, nodal burden, disease recurrence-free survival (DRFS) and overall survival (OS) in clinical practice. In addition, the cutoff values of perpendicular diameter ENE (PD-ENE) and circumferential diameter ENE (CD-ENE) of ENE were investigated. A total of 402 cases of primary invasive breast cancer were extracted from Fudan University Shanghai Cancer Center; these patients underwent axillary lymph node dissection (ALND) between 2010 and 2015. ENE in the ALN was defined as the tumor cells breaking through the lymph node capsule into peripheral adipose tissue and causing connective tissue reactions. Relationships between ENE and clinicopathological features, nodal burden, disease recurrence-free survival (DRFS) and overall survival (OS) were analyzed. PD-ENE was defined by measuring from the point where tumor tissue broke the node capsule to the highest point of the tumor cells in the perinodal adipose tissue.K The average PD-ENE was 1.8 mm; therefore, we divided ENE-positive patients into two groups: PD-ENE no greater than 2 mm and PD-ENE greater than 2 mm. CD-ENE was defined as measuring along the nodal capsule as the distance between peripheral edges of the ENE area. According to the average circumferential diameter (CD-ENE), we classified ENE-positive patients into two groups: CD-ENE no greater than 3 mm and CD-ENE greater than 3 mm. Correlations between ENE cutoffs and prognosis were analyzed. In this cohort of patients, 158 (39.3%) cases were positive for ENE in ALN.98 (24.4%) cases had PD-ENE no larger than 2 mm, and 60 (14.9%) cases had PD-ENE larger than 2 mm. Also, 112 (27.9%) cases had CD-ENE no larger than 3 mm, and 46 (11.4%) cases had CD-ENE larger than 3 mm. Statistical analysis indicated that histological grade, N stage, and HER2 overexpression subtype were associated with ENE. The presence of ENE had significant statistical correlations with nodal burden, including N stage, median metastatic tumor diameter and peri-lymph node vascular invasion (p < 0.001, p < 0.001, p = 0.001, respectively). Cox regression analysis demonstrated that patients with ENE exhibited significantly reduced DRFS in both univariable analysis (HR 2.126, 95% CI 1.453–3.112, p < 0.001) and multivariable analysis (HR 1.745, 95% CI 1.152–2.642, p = 0.009) compared with patients without ENE. For overall survival (OS), patients with ENE were associated with OS in univariable analysis (HR 2.505, 95% CI 1.337–4.693, p = 0.004) but not in multivariable analysis (HR 1.639, 95% CI 0.824–3.260, p = 0.159). Kaplan–Meier curves and log-rank test showed that patients with ENE in ALN had lower DRFS and OS (for DRFS: p < 0.0001; and for OS: p = 0.002, respectively). However, neither the PD-ENE group (divided by 2 mm) nor the CD-ENE group (divided by 3 mm) exhibited significant differences regarding nodal burden and prognosis. Our study indicated that ENE in the ALN was a predictor of prognosis in breast cancer. ENE was an independent prognostic factor for DRFS and was associated with OS. ENE in the ALN was associated with a higher nodal burden. The size of ENE, which was classified by a 3-mm (CD-ENE) or 2-mm (PD-ENE) cutoff value, had no significant prognostic value in this study. Based on our findings, the presence of ENE should be included in routine pathological reports of breast cancers. However, the cutoff values of ENE warrant further investigation.

Ultrastaging methods of sentinel lymph nodes in endometrial cancer - a systematic review

OBJECTIVE

Sentinel lymph node mapping has emerged as an alternative to lymphadenectomy in evaluating the lymph node status in endometrial cancer. Several pathological methods to examine the sentinel lymph node are applied internationally. The aim of this study was to determine the value of ultrastaging and to assess the ultrastaging method with the highest detection rate of metastases.

METHODS

A systematic review was conducted. Inclusion criteria were: pathologically-confirmed endometrial cancer with sentinel lymph node mapping, report of the histological outcomes, metastases found by hematoxylin and eosin staining and metastases found by ultrastaging were separately mentioned, and description of the ultrastaging method. The primary outcome was the detection of metastases found by ultrastaging that were not detected by routine hematoxylin and eosin staining. The secondary outcome was the difference in detection rate of metastases between several ultrastaging methods. Random effects meta-analyses were conducted.

RESULTS

Fifteen studies were selected, including 2259 patients. Sentinel lymph nodes were examined by routine hematoxylin and eosin staining. Subsequently, multiple ultrastaging methods were used, with differences in macroscopic slicing (bread-loaf/longitudinal), number of microscopic slides, and distance between slides, but all used immunohistochemistry. A positive sentinel lymph node was found in 14% of patients. In 37% of these, this was detected only by ultrastaging. Using more ultrastaging slides did not result in a higher detection rate. Bread-loaf slicing led to a higher detection rate compared with longitudinal slicing (mean detection rates 53% and 33%, respectively).

CONCLUSION

Pathological ultrastaging after routine hematoxylin and eosin staining in endometrial cancer patients has led to an increased detection rate of sentinel lymph node metastases. Different ultrastaging methods are used, with a preference for bread-loaf slicing. However, due to the large heterogeneity of the studies, assessing which ultrastaging method has the highest detection rate of sentinel lymph node metastases was not possible.

Model-based system matrix for iterative reconstruction in sub-diffuse angular-domain fluorescence optical projection tomography

This work concerns a fluorescence optical projection tomography system for low scattering tissue, like lymph nodes, with angular-domain rejection of highly scattered photons. In this regime, filtered backprojection (FBP) image reconstruction has been shown to provide reasonable quality images, yet here a comparison of image quality between images obtained by FBP and iterative image reconstruction with a Monte Carlo generated system matrix, demonstrate measurable improvements with the iterative method. Through simulated and experimental phantoms, iterative algorithms consistently outperformed FBP in terms of contrast and spatial resolution. Moreover, when projection number was reduced, in order to reduce total imaging time, iterative reconstruction suppressed artifacts that hampered the performance of FBP reconstruction (structural similarity of the reconstructed images with "truth" was improved from 0.15 ± 1.2 × 10^-3 to 0.66 ± 0.02); and although the system matrix was generated for homogenous optical properties, when heterogeneity (62.98 cm^-1 variance in µ_s ) was introduced to simulated phantoms, the results were still comparable (structural similarity homo: 0.67 ± 0.02 vs hetero: 0.66 ± 0.02).

Intraoperative Detection of Micrometastases in Whole Excised Lymph Nodes Using Fluorescent Paired-Agent Imaging Principles: Identification of a Suitable Staining and Rinsing Protocol

PURPOSE

Correctly identifying nodal status is recognized as a critical prognostic factor in many cancer types and is essential to guide adjuvant treatment. Currently, surgical removal of lymph nodes followed by pathological examination is commonly performed as a standard-of-care to detect node metastases. However, conventional pathology protocols are time-consuming, yet less than 1 % of lymph node volumes are examined, resulting in a 30-60 % rate of missed micrometastases (0.2-2 mm in size).

PROCEDURES

This study presents a method to fluorescently stain excised lymph nodes using paired-agent molecular imaging principles, which entail co-administration of a molecular-targeted imaging agent with a suitable control (untargeted) agent, whereby any nonspecific retention of the targeted agent is accounted for by the signal from the control agent. Specifically, it was demonstrated that by dual-needle continuous infusion of either an antibody-based imaging agent pair (epidermal growth factor receptor (EGFR) targeted agent: IRDye-800CW labeled Cetuximab; control agent: IRDye-700DX-IgG) or an Affibody-based pair (EGFR targeted Affibody® agent: ABY-029; control agent IRDYe-700DX carboxylate) at 0.3 ml/min.

RESULTS

The results demonstrated the possibility to achieve >99 % sensitivity and > 95 % specificity for detection of a single micrometastasis (~0.2 mm diameter) in a whole lymph node within 22 min of tissue processing time.

CONCLUSION

The detection capabilities offer substantial improvements over existing intraoperative lymph node biopsy methods (e.g., frozen pathology has a micrometastasis sensitivity <20 %).

Positive Lymph Node Counts in American Thyroid Association Low-Risk Papillary Thyroid Carcinoma Patients

BACKGROUND

Current American Thyroid Association (ATA) guidelines state that patients with intermediate-risk papillary thyroid cancer (PTC) may benefit from remnant ablation. One criterion for intermediate-risk classification is >5 positive lymph nodes (LNs). We investigate whether performing step-sectioning of LNs increases the metastatic detection rate, thereby influencing ATA risk of recurrence (ROR) classification.

METHODS

A retrospective review was conducted of cases in which ≥ 5 LNs were removed during thyroidectomy and ≤5 LNs were found positive for PTC. Step-sectioning was performed on the original tissue blocks. All slides were re-reviewed by a senior pathologist.

RESULTS

Twenty patients met study criteria. Step-sectioning significantly increased LN yield compared to standard sectioning. In total, we found 12 new positive lymph nodes; seven (58%) were in totally new lymph nodes, while five (42%) were in lymph nodes previously read as negative. All newly discovered metastases were classified as micrometastases (≤2 mm). Of the 15 patients originally classified as low-risk, the step-sectioning protocol impacted two patients (13%), increasing ROR stratification.

CONCLUSION

Intensive step-sectioning reveals additional micrometastases. More detailed analysis did not identify clinically significant nodal disease likely to impact the clinical course of patients in this study. Our study supports current standards of pathology specimen handling related to LN assessment and the impact on ATA ROR classification. Nonetheless, it is important for clinicians to understand their institution's sectioning protocol utilized to report positive and total LN counts, which could impact ATA risk stratification and denote the comprehensive nature of the LN dissection that was performed.

Characterization of an angular domain fluorescence optical projection tomography system for mesoscopic lymph node imaging

Transmittance and fluorescence optical projection tomography can offer high-resolution and high-contrast visualization of whole biological specimens; however, applications are limited to samples exhibiting minimal light scattering. Our previous work demonstrated that angular-domain techniques permitted imaging of ∼1cm diameter noncleared lymph nodes because of their low scattering nature. Here, an angle-restricted transmittance/fluorescence system is presented and characterized in terms of geometric and fluorescence concentration reconstruction accuracy as well as spatial resolution, depth of focus, and fluorescence limits of detection. Using lymph node mimicking phantoms, results demonstrated promising detection and localization capabilities relevant for clinical lymph node applications.

Improved detection of sentinel lymph node metastases allows reliable intraoperative identification of patients with extended axillary lymph node involvement in early breast cancer

An improved procedure that allows accurate detection of negative sentinel lymph node (SLN) and of SLN macrometastases during surgery would be highly desirable in order to protect patients from further surgery and to avoid unnecessary costs. We evaluated the accuracy of an intraoperative procedure that combines touch imprint cytology (TIC) and subsequent frozen section (FS) analysis. 2276 SLNs from 1072 patients with clinical node-negative early breast cancer were evaluated during surgery using TIC. Only cytologically-positive SLN were subsequently analysed with a single FS, preserving cytologically-negative SLN for the final postoperative histological diagnosis. Sensitivity, specificity and the accuracy of this approach were analysed by comparing the results from intra- and postoperative SLN and axillary node evaluation. This intraoperative method displayed 100% specificity for SLN metastases and was significantly more sensitive for prognostically relevant macrometastases (85%) than for micrometastases (10%). Sensitivity was highest for patients with two or more positive LNs (96%) than for those with only one (72%). 98% of the patients with final pN2a-pN3a were already identified during surgery. Patients who received primary axillary lymph node dissection had significantly more frequent metastases in further LNs (44.6%). Sensitivity was highest for patients with luminal-B, HER2+ and triple negative breast cancer and for any subtype if Ki-67 > 40%. TIC and subsequent FS of cytologically-positive SLNs is highly reliable for detection of SLN macrometastases, and allows accurate identification of patients with a high risk of extended axillary involvement during surgery, as well as accurate histological diagnosis of negative SLN.

Breast Sentinel Lymph Node Frozen Section Practice: An Enterprise Audit as a Guide for Moving Forward

CONTEXT.—

In recent years, there has been a shift to less aggressive surgical management of the axilla in breast cancer. Consequently, sentinel lymph node evaluation by frozen section (FS) has declined. Additionally, there has been an impetus to decrease efforts in identifying small sentinel lymph node metastases.

OBJECTIVES.—

To critically evaluate our enterprise performance in evaluating axillary sentinel lymph nodes submitted for FS prior to considering changes in processing.

DESIGN.—

A retrospective review (August 1, 2017-July 31, 2019) was conducted to identify sentinel and nonsentinel lymph nodes from 1 academic institution and 2 community sites. Cases were evaluated for grossing technique and discordance between FS and permanent section (PS) due to sampling and/or interpretive error. Clinicopathologic features were assessed.

RESULTS.—

Lymph nodes from 426 patients with 432 neoplasms were sent for FS. Serial sectioning at 2-mm intervals was adhered to in 338 of 432 (78.2%). Serial sectioning was significantly lower at the community sites (14 of 60; 23.3%) versus at the academic institution (324 of 372; 87.1%; P < .001). Discordant cases were all false negatives (21 of 432; 4.8%). A total of 7 of 21 false negatives (33.3%) had macrometastatic (>2 mm) disease; of these, 3 were post-neoadjuvant chemotherapy, 3 were neither serially sectioned nor posttherapy, and 1 was a small (0.3-cm) focus. A total of 15 of 16 false negatives due to sampling error were detected on the first permanent section level.

CONCLUSIONS.—

Standard serial sectioning of sentinel lymph nodes at 2-mm intervals resulted in infrequent false negatives due to macrometastatic disease. A single additional permanent section level is reasonable, given adherence to serial sectioning.

Evaluation of an enhanced pathological examination protocol for sentinel lymph nodes from patients with breast carcinoma

Clinical trials have shown that many patients with breast cancer with limited sentinel lymph node (SLN) metastatic disease can safely avoid axillary lymph node dissection. Ultra-staging of initially negative SLNs may not confer additional clinical benefit. Despite this, protocols of 'enhanced pathological examination' (EPE) are still widely used. We evaluated the impact of our EPE protocol. If initial SLN H&Es are negative, we cut three additional H&E levels at 500 µm intervals with two spare sections at each level, to allow for immunohistochemistry if necessary. Occult micrometastases or isolated tumour cells were identified, using this protocol, in 3.4%, resulting in change of N stage in 3%. 1% of patients had further axillary surgery based on these findings. Our SLN-EPE protocol provided additional information in a small number of cases and changed axillary management in a minority. It represented a significant workload for scientists and pathologists, and had time and cost implications. We concluded that emphasising careful gross examination along with judicious use of additional levels and immunohistochemistry may be more beneficial than our current protocol.

Clinical significance of extranodal extension in sentinel lymph node positive breast cancer

The precise stage of lymph node (LN) metastasis is a strong prognostic factor in breast cancers, and sentinel lymph node (SLN) is the first station of nodal metastasis. A number of patients have extranodal extension (ENE) in SLN, whereas the clinical values of ENE in SLN in breast cancers are still in exploration. The aim of our study was to evaluate the predictive and prognostic values of ENE in SLN in breast cancers, and to investigate the feasibility of ENE to predict non-SLN metastasis, nodal burden, disease free survival (DFS) and overall survival (OS) in clinical practice. 266 cases of primary invasive breast cancer (cT1-2N0 breast cancer) underwent SLN biopsy and axillary lymph node dissection (ALND) between 2008 and 2015 were extracted from the pathology database of Fudan University Shanghai Cancer Center. ENE in SLN was defined as extension of neoplastic cells through the lymph-nodal capsule into the peri-nodal adipose tissue, and was classified as no larger than 2 mm and larger than 2 mm group. The associations between ENE and clinicopathological features, non-SLN metastasis, nodal burden, DFS, and OS were analyzed. In the 266 patients with involved SLN, 100(37.6%) were positive for ENE in SLN. 67 (25.2%) cases had ENE no larger than 2 mm in diameter, and 33(12.4%) had ENE larger than 2 mm. Among the clinicopathological characteristics, the presence of ENE in SLN was associated with higher pT and pN stages, PR status, lympho-vascular invasion. Logistic regression analysis indicated that patients with ENE in SLN had higher rate of non-SLN metastasis (OR4.80, 95% CI 2.47–9.34, P < 0.001). Meanwhile, in patients with SLN micrometastasis or 1–2 SLNs involvement, ENE positive patients had higher rate of non-SLN metastasis, comparing with ENE negative patients (P < 0.001, P = 0.004 respectively). The presence of ENE in SLN was correlated with nodal burden, including the pattern and number of involved SLN (P < 0.001, P < 0.001 respectively), the number of involved non-SLN and total positive LNs (P < 0.001, P < 0.001 respectively). Patients with ENE had significantly higher frequency of pN2 disease (P < 0.001). For the disease recurrence and survival status, Cox regression analysis showed that patients with ENE in SLN had significantly reduced DFS (HR 3.05, 95%CI 1.13–10.48, P = 0.008) and OS (HR 3.34, 95%CI 0.74–14.52, P = 0.092) in multivariate analysis. Kaplan–Meier curves and log-rank test showed that patients with ENE in SLN had lower DFS and OS (for DFS: P < 0.001; and for OS: P < 0.001 respectively). Whereas no significant difference was found in nodal burden between ENE ≤ 2 mm and > 2 mm groups, except the number of SLN metastasis was higher in patients with ENE > 2 mm. Cox regression analysis, Kaplan–Meier curves and log-rank test indicated that the size of ENE was not an independent factor of DFS and OS. Our study indicated that ENE in SLN was a predictor for non-SLN metastasis, nodal burden and prognosis in breast cancers. Patients with ENE in SLN had a higher rate of non-SLN metastasis, higher frequency of pN2 disease, and poorer prognosis. Patients with ENE in SLN may benefit from additional ALND, even in SLN micrometastasis or 1–2 SLNs involvement patients. The presence of ENE in SLN should be evaluated in clinical practice. Size of ENE which was classified by a 2 mm cutoff value had no significant predictive and prognostic values in this study. The cutoff values of ENE in SLN need further investigation.

Two ultrastaging protocols for the detection of lymph node metastases in early-stage cervical and endometrial cancers

OBJECTIVE

To date, there is no universal consensus on which is the optimal ultrastaging protocol for sentinel lymph node (SLN) evaluation in gynecologic malignancies. To estimate the impact of different ultrastaging methods of SLNs on the detection of patients with nodal metastases in early-stage cervical and endometrial cancers and to describe the incidence of low-volume metastases between two ultrastaging protocols.

METHODS

We retrospectively compared two ultrastaging protocols (ultrastaging-A vs ultrastaging-B) in patients with clinical stage I endometrial cancer or FIGO stage IA-IB1 cervical cancer who underwent primary surgery including SLN biopsy from October 2010 to December 2017 in our institution. The histologic subtypes and grades of the tumors were evaluated according to WHO criteria. Only SLNs underwent ultrastaging, while other lymph nodes were sectioned and examined by routine hematoxylin and eosin (H&E).

RESULTS

Overall 224 patients were reviewed (159 endometrial cancer and 65 cervical cancer). Lymph node involvement was noted in 15% of patients with endometrial cancer (24/159): 24% of patients (9/38) with the ultrastaging protocol A and 12% (15/121) with the ultrastaging protocol B (p=0.08); while for cervical cancer, SLN metastasis was detected in 14% of patients (9/65): 22% (4/18) in ultrastaging-A and 11% (5/47) in ultrastaging-B (p=0.20). Overall, macrometastasis and low-volume metastases were 50% and 50% for endometrial cancer and 78% and 22% for cervical cancer. Median size of nodal metastasis was 2 (range 0.9-8.5) mm for the ultrastaging-A and 1.2 (range 0.4-2.6) mm for the ultrastaging-B protocol in endometrial cancer (p=0.25); 4 (range 2.5-9.8) mm for ultrastaging-A and 4.4 (range 0.3-7.8) mm for ultrastaging-B protocol in cervical cancer (p=0.64).

CONCLUSION

In endometrial or cervical cancer patients, the incidence of SLN metastasis was not different between the two different types of ultrastaging protocol.

[Pathological process for sentinel lymph node]

Sentinel node is defined as the first node to receive drainage from a primary tumor and seems to reflect the nodal status in the lymphatic drainage of the tumor. Sentinel node technique has modified the pathological examination of lymph nodes, with intraoperative evaluation of sentinel node, allowing immediate lymph node dissection in case of positive sentinel node, and histological ultrastratification to detect occult metastases. This is a literature review of different histological protocols of sentinel node according to different organs. Except for sentinel node in breast cancer and melanoma, intraoperative examination of sentinel node is helpful using frozen section, more sensitive than touch imprint cytology. Sentinel node should be embedded in paraffin block entirely after gross sectioning at two millimeters intervals parallel to the long axis of the node. Histological ultrastaging with serial sections can be helpful, but the number of sections and the interval between them is not codified. Three sections at 200-250 microns can identify the majority of micrometastases (<2mm and >200 microns). Systematic immunohistochemistry of sentinel node is not necessary for breast cancers, since isolated tumor cells do not modify the therapeutic strategy, but remains useful in other organs.

Postmastectomy radiation therapy in early breast cancer: Utility or futility?

Postmastectomy radiation therapy (PMRT) has been shown to reduce the risk of locoregional recurrence (LRR), in patients with locally advanced breast cancer who are considered of high-risk because of large tumors (>5 cm) or presence of axillary lymph-node involvement, as well as to reduce breast cancer mortality. However, controversy still remains with respect to indication of PMRT in case of early-stages invasive tumors. This review aims to analyze the impact that PMRT has on final results in women with breast tumors in different scenarios that would otherwise be considered as early breast cancer, such as extensive DCIS, tumors without axillary lymph-node involvement or with minimal microscopic nodal-involvement. The existence of risk factors including young age, premenopausal status, and presence of lymphovascular invasion (LVI), high grade or tumor size >2 cm has been associated with an increased risk of LRR in these patients at early-stages and advises to consider PMRT in selected cases.

Angular restriction fluorescence optical projection tomography to localize micrometastases in lymph nodes

Lymph node biopsy is a primary means of staging breast cancer, yet standard pathological techniques are time-consuming and typically sample less than 1% of the total node volume. A low-cost fluorescence optical projection tomography (OPT) protocol is demonstrated for rapid imaging of whole lymph nodes in three dimensions. The relatively low scattering properties of lymph node tissue can be leveraged to significantly improve spatial resolution of lymph node OPT by employing angular restriction of photon detection. It is demonstrated through porcine lymph node metastases models that simple filtered-backprojection reconstruction is sufficient to detect and localize 200-μm-diameter metastases (the smallest clinically significant) in 1-cm-diameter lymph nodes.

Discrepancy Between the Clinical and Final Pathological Findings of Lymph Node Metastasis in Superficial Esophageal Cancer

BACKGROUND

Recent advances in endoscopic examinations have resulted in the detection of a larger number of early esophageal cancers; however, there have been many cases with clinically negative but pathologically positive lymph node metastasis (LNM). In this study, we aimed to evaluate the discrepancy between the clinical and pathological diagnoses of LNM in patients with cT1a-MM/cT1b N0M0 esophageal cancer, and assess LNM size in these patients to clarify the presence of LNM that cannot be detected with current modalities.

METHODS

This study included 50 patients who underwent surgery for cT1a-MM/cT1b N0M0 thoracic esophageal squamous cell carcinoma between January 2012 and November 2016 at our institution. The maximum size of involved LNs and metastatic nests were measured, and the distribution of LNM was investigated.

RESULTS

Of the 50 patients, 13 (26%) had LNM on pathological examination. Lymphatic invasion was significantly more frequent in the LNM-positive group than in the LNM-negative group (p = 0.005). The median sizes of 28 involved LNs and metastatic nests were 3 and 1.6 mm, respectively. Of these LNs, 20 (71%) were classified as micrometastases (≤ 2 mm). The involved nodes were distributed across three fields.

CONCLUSIONS

There was a discrepancy between the clinical and final pathological findings of LNM in patients with cT1a-MM/cT1b N0M0 esophageal cancer. The detection of involved nodes with current modalities in these patients was difficult because of the small size of LNM. Therefore, continued strong consideration for extended LN dissection is necessary in these patients to ensure appropriate diagnosis and treatment.