Identification Of Tumor Tissue Research Articles

Topical dual-probe staining using quantum dot-labeled antibodies for identifying tumor biomarkers in fresh specimens.

PurposeRapid, intra-operative identification of tumor tissue in the margins of excised specimens has become an important focus in the pursuit of reducing re-excision rates, especially for breast conserving surgery. Dual-probe difference specimen imaging (DDSI) is an emerging approach that uses the difference in uptake/clearance kinetics between a pair of fluorescently-labeled stains, one targeted to a biomarker-of-interest and the other an untargeted isotype, to reveal receptor-specific images of the specimen. Previous studies using antibodies labeled with either enhanced Raman particles or organic fluorophores have shown promising tumor vs. normal diagnostic performance. Yet, the unique properties of quantum dot-labeled antibody complexes (QDACs), which provide spectrally-distinct fluorescence emission from a common excitation source, make them ideal candidates for this application. Herein, we evaluate the diagnostic performance of QDAC-based DDSI in excised xenografts.ProceduresExcised fresh specimens of normal tissue and human tumor xenografts with elevated expression of HER2 were stained with a HER2-targeted QDAC and an untargeted QDAC isotype. Stained specimens were imaged on a custom hyperspectral imaging system capable of spectrally separating the quantum dot signatures, and images processed using the DDSI approach. The diagnostic performance of this technique under different incubation temperatures and probe concentrations was evaluated using receiver-operator characteristic analysis.ResultsHER2-targeted QDAC-DDSI was able to distinguish HER2(+) tumors from normal tissue with reasonably high diagnostic performance; however, this performance was sensitive to temperature during the staining procedure. Area under the curve values were 0.61 when staining at room temperature but increased to over 0.81 when staining at 37 °C. Diagnostic performance was not affected by increasing stain concentration.ConclusionsThis study is the first to report dual-probe difference imaging of specimens using QDACs and hyperspectral imaging. Our results show promising diagnostic performance under certain conditions, and compel further optimization and evaluation of this intra-operative margin assessment technique.

Pancreatic Ductal Adenocarcinoma: Molecular Expression Patterns after Neoadjuvant FOLFIRINOX Treatment.

Background: Positive margin (R1) rates following pancreatic cancer resection vary between 20-75% (Tummers 2019). The clinical relevance of this is underlined by the two-fold increase in survival time after radical (R0) compared to R1 resection rates (Tummers, 2019). Distinguishing pancreatic ductal adenocarcinoma (PDAC) from peritumoral inflammation, tumor necrosis and fibrosis induced by neoadjuvant treatment is challenging. Molecular targeted imaging using fluorescence is an intra-operative technique which could aid in tumor tissue identification. Previous research has shown alterations in tumor cell molecular expression patterns following neoadjuvant chemotherapy. As neoadjuvant treatment strategies are being adopted into pancreatic cancer guidelines, determining the effect of neoadjuvant treatment regimens on PDAC molecular status is of evident importance for targeted fluorescence imaging (Boogerd, 2018).

Inline cartridge extraction for rapid brain tumor tissue identification by molecular profiling

The development of perspective diagnostic techniques in medicine requires efficient high-throughput biological sample analysis methods. Here, we present an inline cartridge extraction that facilitates the screening rate of mass spectrometry shotgun lipidomic analysis of tissue samples. We illustrate the method by its application to tumor tissue identification in neurosurgery. In perspective, this high-performance method provides new possibilities for the investigation of cancer pathogenesis and metabolic disorders.

Laser Ablation Electrospray Ionization Time-of-Flight Mass Spectrometry for Direct Analysis of Biological Tissue.

Direct analysis and identification of biological tissue is significant for clinical applications. In this study, porcine liver and kidney have been analyzed using laser ablation electrospray ionization time-of-flight mass spectrometry (LAESI-TOFMS). This method showed good reproducibility for the same types of tissue and is capable of distinguishing different tissue species. The margin assessment was also performed using porcine renal tissue, and the response time was less than 6 s. Furthermore, human hepatocarcinoma tissue and normal tissue were identified using this method. Our results indicate that LAESI-TOFMS is a feasible approach for direct identification of tumor tissue and potential for assessment of the resection margin.

Characterizing the heterogeneity in 5-aminolevulinic acid-induced fluorescence in glioblastoma.

5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is an effective surgical adjunct for the intraoperative identification of tumor tissue during resection of high-grade gliomas. The use of 5-ALA-induced PpIX fluorescence in glioblastoma (GBM) has been shown to double the extent of gross-total resection and 6-month progression-free survival. The heterogeneity of 5-ALA-induced PpIX fluorescence observed during surgery presents a technical and diagnostic challenge when utilizing this tool intraoperatively. While some regions show bright fluorescence after 5-ALA administration, other regions do not, despite that both regions of the tumor may be histopathologically indistinguishable. The authors examined the biological basis of this heterogeneity using computational methods. The authors collected both fluorescent and nonfluorescent GBM specimens from a total of 14 patients undergoing surgery and examined their gene expression profiles. In this study, the authors found that the gene expression patterns characterizing fluorescent and nonfluorescent GBM surgical specimens were profoundly different and were associated with distinct cellular functions and different biological pathways. Nonfluorescent tumor tissue tended to resemble the neural subtype of GBM; meanwhile, fluorescent tumor tissue did not exhibit a prominent pattern corresponding to known subtypes of GBM. Consistent with this observation, neural GBM samples from The Cancer Genome Atlas database exhibited a significantly lower fluorescence score than nonneural GBM samples as determined by a fluorescence gene signature developed by the authors. These results provide a greater understanding regarding the biological basis of differential fluorescence observed intraoperatively and can provide a basis to identify novel strategies to maximize the effectiveness of fluorescence agents.

Fluorescein Sodium in the Surgical Treatment of Recurrent Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is the most common primary brain tumor and has a high recurrence rate. Maximizing the extent of resection (EOR) in recurrent GBM has proved to be the cornerstone of neurosurgical retreatment. The development of surgical microscopes fitted with fluorescein-specific filters has facilitated fluorescein-guided microsurgery and the identification of tumor tissue. Use of fluorescein sodium (FL) in primary high-grade glioma resection has shown promising results. Here, we present our experience with FL and the dedicated surgical microscope filter YELLOW 560 nm in 106 patients with recurrent GBM. A total of 106 patients with recurrent GBM were included (53 women, 53 men; mean age, 53 years). A total of 5 mg/kg bodyweight of FL was intravenously injected approximately 45 minutes before craniotomy. A YELLOW 560 nm filter (PENTERO 900 [Carl Zeiss Meditec, Oberkochen Germany]) was used for microsurgical tumor resection and resection control. Surgical reports were reviewed regarding the degree of fluorescent staining. Postoperative magnetic resonance images were examined within 48 hours after surgery regarding the EOR and postoperative course regarding neurologic outcome, complications, and any adverse events. Bright fluorescent staining was present in all patients, which markedly enhanced tumor visibility and was deemed helpful for tumor resection. Seventeen patients (16%) showed residual tumor tissue on postoperative magnetic resonance imaging (MRI). Therefore, gross total resection was achieved in 89 patients (84%). No adverse events were registered postoperatively. FL and YELLOW 560 nm are readily available methods for fluorescence-guided tumor resection, similar to contrast enhancement in T1-weighted MRI. FL may improve resection in recurrent GBM with minimal risk, and tumor margins are clearly visualized. FL and the YELLOW 560 nm filter are safe and feasible tools for safe maximal resection of recurrent glioblastoma.

Auditory and Visual User Interface for Optical Guidance During Stereotactic Brain Tumor Biopsies.

During stereotactic brain tumor biopsies, the detection of protoporphyrin IX (PpIX) fluorescence and microvascular perfusion using laser Doppler flowmetry (LDF) with a handheld fiber optic probe allows the identification of tumor tissue while decreasing the risk of intracranial hemorrhage. Neurosurgeons performing this procedure usually view the measurement values on a screen. When their visual focus is directed at the surgical site, they require an assistant to verbally relay the values. An auditory and visual user interface (UI), which displays measurement values accurately and allows fast and intuitive signal recognition, can improve this procedure. This paper experimentally evaluates an auditory and visual UI for providing real-time measurement feedback during stereotactic brain tumor biopsies. In a user study (n = 15), the accuracy of auditory and visual response was determined using function response tests, and user acceptance was evaluated. The auditory signals proved to be intuitive and easy to recognize and remember. The visual display of measurement values was easy to understand and facilitated the user's decision-making process. Moreover, the UI exhibited high user acceptance.

Tumor Tissue Identification Technology by Estimating Features of Immunostaining Images using Convolutional Neural Networks

Tumor Tissue Identification Technology by Estimating Features of Immunostaining Images using Convolutional Neural Networks

Intraoperative optical imaging of metabolic changes after direct cortical stimulation - a clinical tool for guidance during tumor resection?

Brain tumor resection is even today one of the most challenging disciplines in neurosurgery. The current state of the art for the identification of tumor tissue during the surgical procedure comprises a wide variety of different tools, each with its own limitations and drawbacks. In this paper, we present a novel approach, the use of optical imaging in connection with direct electrical cortical stimulation (DCS), for identification of impaired tumor tissue and functional intact normal brain tissue under intraoperative conditions. Measurements with an optical imaging setup were performed as a proof of concept on three patients who underwent tumor resection of superficial gliomas. Direct electrical stimulations were applied on tumor tissue and surrounding brain tissue in each patient and characteristic features from the observed changes in the optical properties were compared between the different groups. The results reveal that in all patients a differentiation between non-functional tumor tissue and functional intact brain tissue was possible, and the technique might be a useful clinical tool in the future.

Rapid discrimination of human oesophageal squamous cell carcinoma by mass spectrometry based on differences in amino acid metabolism

Oesophageal cancer (OC) is associated with high morbidity and mortality, and surgery is the most effective approach to treat it. In order to reduce surgical risks and duration of surgery, we explored a new strategy to determine tumour margins in surgery. In this study, we included 128 cancerous and 128 noncancerous database entries obtained from 32 human patients. Using internal extractive electrospray ionization-MS, in positive ion detection mode, the relative abundances of m/z 104.13, m/z 116.10, m/z 132.13, and m/z 175.13 were higher in cancer tissue while the relative abundances of m/z 82.99, m/z 133.11, m/z 147.08, m/z 154.06, and m/z 188.05 were higher in normal tissue. Using partial least squares analysis, the mass spectra of cancer samples was discriminated from those of normal tissues, and the discriminatory ions were obtained from loading plots. Dimethylglycine(m/z 104), proline(m/z 116), isoleucine(m/z 132), asparagine(m/z 133), glutamine(m/z 147), and arginine(m/z 175) were identified by collision-induced dissociation experiments. Using the ROC curve analysis, we verified the validity of six amino acids for the identification of tumour tissue. Further investigations of tissue amino acids may allow us to better understand the underlying mechanisms involved in OC and develop novel means to identify tumour tissue during operation.

Fluorescence lifetime-based contrast enhancement of indocyanine green-labeled tumors.

Although the development of tumor-targeted fluorescent probes is a major area of investigation, it will be several years before these probes are realized for clinical use. Here, we report an approach that employs indocyanine-green (ICG), a clinically approved, nontargeted dye, in conjunction with fluorescence lifetime (FLT) detection to provide high accuracy for tumor-tissue identification in mouse models of subcutaneous human breast and brain tmors. The improved performance relies on the distinct FLTs of ICG within tumors versus tissue autofluorescence and is further aided by the well-known enhanced permeability and retention of ICG in tumors and the clearance of ICG from normal tissue several hours after intravenous injection. We demonstrate that FLT detection can provide more than 98% sensitivity and specificity, and a 10-fold reduction in error rates compared to intensity-based detection. Our studies suggest the significant potential of FLT-contrast for accurate tumor-tissue identification using ICG and other targeted probes under development, both for intraoperative imaging and for ex-vivo margin assessment of surgical specimens.

Tumor Tissue Identification Technology by Automatic Classification of Stained Images and Convolutional Neural Networks

Tumor Tissue Identification Technology by Automatic Classification of Stained Images and Convolutional Neural Networks

Fluorescence-guided resection of high-grade gliomas: A systematic review and meta-analysis

The present systematic review and meta-analysis was to analyze of the advantages of intraoperative fluorescence-guided resection of high-grade gliomas. Systematic computerized searches of the PubMed and Web of Knowledge were performed. The outcomes included diagnostic value for identification of tumor tissue, gross total resection, and prognosis. The summary receiver operating characteristic curves (SROC), the pooled sensitivities, the pooled specificities, the pooled odd ratio (OR) and the pooled hazard ratio (HR) were estimated by meta-analysis. Twelve studies were included. The pooled sensitivity and the pooled specificity for identification of tumor tissue was 0.84 (95% CI: 0.81-0.87), and 0.91 (95% CI: 0.87-0.94), respectively. And the overall weighted AUC of the SROC curve was 0.9520 ± 0.0116. The summary OR of the gross total resection rate in patients with fluorescein-guided resection compared with patients with no fluorescein was 4.372 (95% CI 2.937-6.508). Fluorescein-guided resection was associated with a reduced risk of progression-free survival compared with no fluorescein, with HR 0.73 (95% CI 0.57-0.94, P = 0.01). The pooled HR of overall survival was 1.000 (95% CI 0.960-1.040) between two groups. No significant publication bias was found. Fluorescence-guided resection of high-grade gliomas is effective for diagnosing tumor margins, increasing gross total resection, and reducing the risk of progression-free survival. But this conclusion should be confirmed by large sample randomized controlled clinical trials.

Brain tumor classification on intraoperative contrast-enhanced ultrasound.

Contrast-enhanced ultrasound (CEUS) imaging of tissue perfusion is based on microbubble echo detection. CEUS can visualize tumors based on local perfusion variations. The acquired video data are qualitatively interpreted by subjective visualization in clinical practice. An automated CEUS classifier was developed for intraoperative identification of tumor tissue and especially tumor borders. Support vector machines (SVM) were trained using CEU data sets to differentiate tumor and non-tumor tissue in glioblastoma patients. The classification was based on features derived from model functions approximated to time courses for each pixel in the video data. Classification performance was evaluated with single and cross- patient training data sets. The minimum mean classification error (14.6 %) with single patient data set training was achieved by SVM training using a sigmoid combination of model function parameter sets. A comparison of different model functions showed that the minimum average classification error (17.4 %) in a cross-validation study with 13 patients was achieved with the sigmoid model using an automatic relevance detection kernel. CEUS-based classification map images derived from approximated model functions can be generated with moderate accuracy and have significant potential to support intraoperative decisions concerning glioblastoma tumor borders.

Fluorescence-guided surgery and biopsy in gliomas with an exoscope system.

Background. The introduction of fluorescence-guided resection allows a better identification of tumor tissue and its more radical resection. We describe our experience with a modified exoscope to detect 5 ALA-induced fluorescence in neuronavigation-guided brain surgery or biopsy of malignant brain tumors. Methods. Thirty-eight patients with a suspected preoperative diagnosis of high-grade astrocytoma were included. We used a neuronavigation device and a high-definition exoscope system with a built-in filter to detect 5-ALA fluorescence in all cases. Thirty patients underwent craniotomy with tumor resection and 8 underwent frameless stereotactic brain biopsy. Results. Histopathological diagnosis confirmed the presence of high-grade gliomas in 34 patients. Total resection was achieved in 23 cases and subtotal in 7. No relevant complications related to the administration of 5-ALA were detected. Conclusions. The use of the exoscope in 5-ALA fluorescence-guided tumor surgery has twofold implications: during brain tumor surgery it can be considered a valuable tool to achieve a more radical resection of the lesion, and when applied to a biopsy of a suspected brain high-grade glioma, it decreases the possibility of a negative biopsy.

A nanoparticle-based strategy for the imaging of a broad range of tumours by nonlinear amplification of microenvironment signals.

Stimuli-responsive nanomaterials are increasingly important in a variety of applications such as biosensing, molecular imaging, drug delivery and tissue engineering. For cancer detection, a paramount challenge still exists in search of methods that can illuminate tumors universally regardless of their genotypes and phenotypes. Here we capitalized on the acidic, angiogenic tumor microenvironment to achieve broad detection of tumor tissues in a wide variety of mouse cancer models. This was accomplished using ultra-pH sensitive fluorescent nanoprobes that have tunable, exponential fluorescence activation upon encountering subtle, physiologically relevant pH transitions. These nanoprobes were silent in the circulation, then dramatically activated (>300 fold) in response to neovasculature or to the low extracellular pH in tumors. Thus, we have established non-toxic, fluorescent nanoreporters that can non-linearly amplify tumor microenvironmental signals, permitting identification of tumor tissue independently of histological type or driver mutation, and detection of acute treatment responses much more rapidly than conventional imaging approaches.

Blinded Comparator Study of Immunohistochemical Analysis versus a 92-Gene Cancer Classifier in the Diagnosis of the Primary Site in Metastatic Tumors

Accurate tumor classification is fundamental to inform predictive biomarker testing and optimize therapy. Gene expression-based tests are proposed as diagnostic aids in cases with uncertain diagnoses. This study directly compared the diagnostic accuracy of IHC analysis versus molecular classification using a 92-gene RT-PCR assay for determination of the primary tumor site. This prospectively defined blinded study of diagnostically challenging cases included 131 high-grade, primarily metastatic tumors. Cases were reviewed and reference diagnoses established through clinical correlation. Blinded FFPE sections were evaluated by either IHC/morphology analysis or the 92-gene assay. The final analysis included 122 cases. The 92-gene assay demonstrated overall accuracy of 79% (95% CI, 71% to 85%) for tumor classification versus 69% (95% CI, 60% to 76%) for IHC/morphology analysis (P = 0.019). Mean IHC use was 7.9 stains per case (median, 8; range, 2 to 15). IHC/morphology analysis accuracy was 79%, 80%, and 46% when 1 to 6 (n = 42), 7 to 9 (n = 41), and >9 (n = 39) IHC stains were used, respectively, versus 81%, 85%, and 69%, respectively, with the 92-gene assay. Results from this blinded series of high-grade metastatic cases demonstrate superior accuracy with the 92-gene assay versus standard-of-care IHC analysis and strongly support the diagnostic utility of molecular classification in difficult-to-diagnose metastatic cancer.

TU‐A‐BRA‐04: Real‐Time Metabolic Image‐Guidance to Aid Intraoperative Radiation Therapy: Pilot Results in a Small‐Animal Model

Purpose: Real‐time biological imaging is being investigated to delineate positive tumor margins which may provide feedback during intraoperative radiation therapy. We investigated the feasibility of identifying prostate cancer invasion through the capsule of the prostate intra‐operatively in a mouse model using Cerenkov optical emission from Fluorodeoxyglucose (FDG). The potential benefit of using Cerenkov emission is that it provides real‐time images of glucose uptake while avoiding signal from the bladder and surrounding structures beyond the surgical margin. We investigated the performance of a Cerenkov imaging system during surgical prostatectomy in vivo in a tumor mouse model. Methods: All Cerenkov images were collected with a commercial optical imaging system. A transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse model was used to investigate the feasibility of imaging local invasion of the cancer beyond the prostate capsule. A mouse with a ∼1cm prostate tumor with questionable invasion as determined by T2‐W MRI was injected with 1.2mCi of FDG. The injection was followed by PET/CT after 75 minutes, and subsequent sacrifice; surgery commenced 3:45 later. After prostatectomy, Cerenkov images were acquired during an attempt to clear the surgical margin. Results: In all, 8 tissue resections were performed in the surrounding tissues including the seminal vesicles, rectum, and other nearby organs. Cerenkov imaging identified tissues both before surgical resection in vivo, and confirmed their successful excision after surgical intervention ex vivo. The Cerenkov imaging confirmed uptake in the seminal vesicles, as is expected in this tumor model. In addition, several hyperintense regions that were not identified in PET/CT were visible with the interventional system. Conclusions: This proof‐of‐concept study explored the feasibility of using Cerenkov based imaging for the interventional identification of tumor tissue that had spread beyond the prostate. A more in‐depth analysis is currently underway to determine the potential benefit to intraoperative radiation therapy. DOD Breast Cancer Fellowship W81XWH‐10‐1‐0506, Center for Biomedical Imaging at Stanford (CBIS), NCI R01 CA128908, NIH ICMIC P50CA114747.

Changes in management and survival outcomes for patients receiving gene-expression-based tissue-of-origin test results for difficult-to-diagnose primary cancers.

397 Background: An important step for a novel test is assessing its clinical utility and real-world effect on diagnosis and patient management. This report describes completed results of a cohort of physicians who have ordered a gene expression profile assay for identification of tumor tissue of origin (Pathwork Tissue of Origin Test) for patients with difficult-to-diagnose primary cancers and their subsequent treatment and survival. Methods: The IRB-approved registry collected data from participating physicians who have ordered the Tissue of Origin test. A detailed interview was conducted using both a web-based questionnaire and a confirmatory telephone interview with the physicians. Chart survey included collection of data on patient demographics, diagnostic procedures including imaging and immunohistochemistry as well as therapy. The physicians were queried regarding their working diagnoses and treatment recommendations prior to and after Tissue of Origin Test result availability. Date of death was also obtained with a minimum of one year follow-up from date of biopsy. Results: One hundred seven patients (61 women) have been studied and 65 participating physicians have completed the interview. Results indicate that most patients underwent extensive evaluation (≥ 10 IHC) prior to gene expression analysis. After receiving test results, physicians changed the primary site diagnosis for 53 patients (50%, CI [43,58%]; p<.001) and changed the treatment management for 72 patients (65%, CI [58%,73%]; p<.0001). At last follow-up, 69 patients had died with a median survival of 426 days. More than 30% of patients were alive at 1000 days. Conclusions: This registry study confirms that in patients with difficult-to-diagnose primary cancers, extensive baseline diagnostics are common and less than half of the patients have an established working diagnosis. Results indicate that the Tissue of Origin Test led to a change in working diagnosis and changed treatment recommendations in over half the patients. Survival outcomes compare favorably to historical controls in treatment trials where median survival is generally less than one year.

Performance and Clinical Evaluation of the 92-Gene Real-Time PCR Assay for Tumor Classification

Accurate determination of cancer origin is necessary to guide optimal treatment but remains a diagnostic challenge. Gene expression profiling technologies have aided the classification of tumors and, therefore, could be applied in conjunction with clinicopathologic correlates to improve accuracy. We report an expanded version of the previously described 92-gene assay to classify 30 main tumor types and 54 histological subtypes, with coverage of ≥95% of all solid tumors based on incidence. Increased tissue coverage was achieved through expansion of a reference tumor database containing 2,206 specimens, with a median of 62 samples per main tumor type. The 92-gene classification algorithm demonstrated sensitivities of 87% and 85% for 30 main types and 54 histological subtypes, respectively, in leave-one-out cross validation, and 83% in a test set of 187 tumors representing 28 of the 30 main cancer types. These findings provide further support that broad and diverse tumor classification can be performed using a relatively compact gene set. An additional 300 consecutive cases submitted for clinical testing were profiled to characterize clinical utility in a real-world setting: the 92-gene assay confirmed 78% of samples having a single suspected primary tumor and provided a single molecular prediction in 74% of cases with two or more differential diagnoses. Further development of the 92-gene RT-PCR assay has resulted in a significant expansion in reportable tumor types and histological features with strong performance characteristics and supports the use of molecular classification as an objective standardized adjunct to current methods.