Preoperative predictors of successful tumour localization by intraoperative molecular imaging with pafolacianine in lung cancer to create predictive nomogram.

OBJECTIVES: Intraoperative molecular imaging (IMI) uses cancer-targeted fluorescent probe to locate nodules. Pafolacianine is a Food and Drug Administration-approved fluorescent probe for lung cancer. However, it has a 8-12% false negative rate for localization. Our goal is to define preoperative predictors of tumour localization by IMI. METHODS: We performed a retrospective review of patients who underwent IMI using pafolacianine for lung lesions from June 2015 to August 2019. Candidate predictors including sex, age, body mass index, smoking history, tumour size, distance of tumour from surface, use of neoadjuvant therapy and positron emission tomography avidity were included. The outcome was fluorescence in vivo and comprehensively included those who were true or false positives negatives. Multiple imputation was used to handle the missing data. The final model was evaluated using the area under the receiver operating characteristic curve. RESULTS: Three hundred nine patients were included in our study. The mean age was 64 (standard deviation 13) and 68% had a smoking history. The mean distance of the tumours from the pleural surface was 0.4 cm (standard deviation 0.6). Smoking in pack-years and distance from pleura had an odds ratio of 0.99 [95% confidence interval: 0.98-0.99; P = 0.03] and 0.46 [95% confidence interval: 0.27-0.78; P = 0.004], respectively. The final model had an area under the receiver operating characteristic curve of 0.68 and was used to create a nomogram that gives a probability of fluorescence in vivo. CONCLUSIONS: Primary tumours that are deeper from the pleural surface, especially in patients with a higher pack-years, are associated with a decreased likelihood of intraoperative localization. We identified a nomogram to predict the likelihood of tumour localization with IMI with pafolacianine.

Molecular Imaging in Precision-Cut Non-Small Cell Lung Cancer Slices.

BACKGROUND: Small animal models remain invaluable for the preclinical study of emerging molecular imaging agents. However, the data obtained in this setting are generated in genetically homogenous animals that do not mimic human pathophysiology. The purpose of this study was to prospectively validate precision-cut lung slices (PCLSs) obtained from patients with lung cancer as a translational tool for the development of targeted fluorophores. METHODS: The lung tissue was gently inflated with 2% Low-Melt Agarose (Fisher, 16520050) to avoid lung damage and minimize inflation pressure. The slices were then loaded into specialized cylindrical cartridges and inserted into a compressotome, and slices 150 to 350 µm thick were cut. Samples were incubated with fluorophore conjugates for ex vivo validation and immunohistochemical staining for receptor expression. RESULTS: A total of 184 unique 3-dimensional, architecturally preserved normal lung and non-small cell lung cancer samples were obtained between 2020 and 2022. The median nodule size was 1.1 ± 0.21 cm for benign lesions and 2.1 ± 0.19 cm for malignant nodules. A total of 101 of 135 (74.8%) malignant lesions were adenocarcinoma spectrum lung cancers. The median viability was 9.78 ± 1.86 days, and 1 µM of FAPL-S0456 (high-affinity fibroblast activation protein [FAP] targeting ligand linked to the near-infrared fluorophore S0456, On Target Laboratories)-targeted near-infrared fluorochrome localization demonstrated correlative labeling of FAP-positive tumor areas with a correlation coefficient of +0.94 (P < .01). There was no FAP fluorochrome uptake in normal lungs (r = -1; P < .001). CONCLUSIONS: PCLSs comprise a novel human tissue-based translational model that can be used to validate the efficacy of molecular imaging fluorochromes. PCLSs preserve the tumor microenvironment and parenchymal architecture that closely resemble the interactions of the immune and stromal components in humans.

A pH-Activatable Nanoprobe Labels Diverse Histologic Subtypes of Human Lung Cancer During Resection.

BACKGROUND: Intraoperative molecular imaging (IMI) uses tumor-targeted optical contrast agents to improve identification and clearance of cancer during surgery. Recently, pH-activatable contrast agents have been developed but none has been tested in lung cancer. Here, we report the successful clinical translation of pegsitacianine (ONM-100), a pH-activatable nanoprobe, for fluorescence-guided lung cancer resection. METHODS: We first characterized the pH setpoint for pegsitacianine fluorescence activation in vitro. We then optimized the specificity, dosing, and timing of pegsitacianine in murine flank xenograft models of lung adenocarcinoma and squamous cell carcinoma. Finally, we tested pegsitacianine in humans undergoing lung cancer surgery as part of an ongoing phase 2 trial. RESULTS: We found that the fluorescence activation of pegsitacianine occurred below physiologic pH in vitro. Using preclinical models of lung cancer, we found that the probe selectively labeled both adenocarcinoma and squamous cell carcinoma xenografts (mean tumor-to-background ratio [TBR] > 2.0 for all cell lines). In the human pilot study, we report cases in which pegsitacianine localized pulmonary adenocarcinoma and pulmonary squamous cell carcinoma (TBRs= 2.7 and 2.4) in real time to illustrate its successful clinical translation and potential to improve surgical management. CONCLUSIONS: This translational study demonstrates the feasibility of pegsitacianine as an IMI probe to label the two most common histologic subtypes of human lung cancer.

Strategies to reduce morbidity following pleurectomy and decortication for malignant pleural mesothelioma.

BACKGROUND: Pleurectomy and decortication (PD) in malignant pleural mesothelioma has a high morbidity mostly associated with aspiration pneumonia (PNA), deep vein thrombosis (DVT), and foreign catheter sepsis. We instituted four strategies to reduce these complications and report our experience. METHODS: This was a retrospective review of patients who underwent PD at the University of Pennsylvania between 2015 and 2022. Our patients underwent standard of care PD in addition to tracheostomy and gastrostomy/jejunostomy tube with therapeutic anticoagulation (AC) leading up to surgery. Measured outcomes were postoperative PNA, DVT, and sepsis. The predicted risk of those same outcomes had patients not undergone the interventions was calculated based on the American College of Surgeons (ACS) surgical risk calculator (SRC). A McNemar's test was used to determine whether the risk of having PNA, DVT and sepsis differed between the two subgroups. RESULTS: Fifty-five patients were included in the study. The mean age was 70 years (SD 6.2) with a mean of 21 (SD 19) pack-years of smoking. PNA, DVT, and catheter-related sepsis occurred in 12, four, and seven patients, respectively. Upon using the ACS SRC prediction model of the nonintervention group, PNA, DVT and catheter related sepsis was predicted to occur in 24 (paired data OR 5, 95% CI: 1.4-17.2; McNemar's test p = 0.008), 14 (paired data OR 3.5, 95% CI: 1.15-10.6; McNemar's test p = 0.03), and 17 (paired OR 3, 95% CI: 1.09-8.3; McNemar's test p = 0.04) patients, respectively. DISCUSSION: Patients undergoing tracheostomy creation, therapeutic AC at the time of diagnosis, and gastrostomy tube placement had a reduced risk of aspiration PNA, DVT, and catheter sepsis.

Preclinical Lymph Node Model for Intraoperative Molecular Imaging of Cancer.

Purpose: Lymph node(LN) dissection is part of most oncologic resections. Intraoperatively identifying a positive LN(+ LN), that harbors malignant cells, can be challenging. We hypothesized that intraoperative molecular imaging(IMI) using a cancer-targeted fluorescent prober can identify + LNs. This study aimed to develop a preclinical model of a + LN and test it using an activatable cathepsin-based enzymatic probe, VGT-309. Procedures: In the first model, we used peripheral blood mononuclear cells (PBMC), representing the lymphocytic composition of the LN, mixed with different concentrations of human lung adenocarcinoma cell line A549. Then, they were embedded in a Matrigel® matrix. A black dye was added to mimic LN anthracosis. Model two was created using a murine spleen, the largest lymphoid organ, injected with various concentrations of A549. To test these models, we co-cultured A549 cells with VGT-309. Mean fluorescence intensity(MFI) was. An independent sample t-test was used to compare the average MFI of each A549:negative control ratio. Results: A significant difference in MFI from our PBMC control was noted when A549 cells were 25% of the LN (p = 0.046) in both 3D cell aggregate models-where the LNs native parenchyma is replaced and the one where the tumor grows over the native parenchyma. For the anthracitic equivalents of these models, the first significant MFI compared to the control was when A549 cells were 9% of the LN (p = 0.002) in the former model, and 16.7% of the LN (p = 0.033) in the latter. In our spleen model, we first noted significance in MFI when A549 cells were 16.67% of the cellular composition.(p = 0.02). Conclusions: A + LN model allows for a granular evaluation of different cellular burdens in + LN that can be assessed using IMI. This first exvivo + LN model can be used in preclinical testing of several existing dyes and in creating more sensitive cameras for IMI-guided LN detection.

Intraoperative molecular imaging: 3rd biennial clinical trials update.

Significance: This third biennial intraoperative molecular imaging (IMI) conference shows how optical contrast agents have been applied to develop clinically significant endpoints that improve precision cancer surgery. Aim: National and international experts on IMI presented ongoing clinical trials in cancer surgery and preclinical work. Previously known dyes (with broader applications), new dyes, novel nonfluorescence-based imaging techniques, pediatric dyes, and normal tissue dyes were discussed. Approach: Principal investigators presenting at the Perelman School of Medicine Abramson Cancer Center's third clinical trials update on IMI were selected to discuss their clinical trials and endpoints. Results: Dyes that are FDA-approved or currently under clinical investigation in phase 1, 2, and 3 trials were discussed. Sections on how to move benchwork research to the bedside were also included. There was also a dedicated section for pediatric dyes and nonfluorescence-based dyes that have been newly developed. Conclusions: IMI is a valuable adjunct in precision cancer surgery and has broad applications in multiple subspecialties. It has been reliably used to alter the surgical course of patients and in clinical decision making. There remain gaps in the utilization of IMI in certain subspecialties and potential for developing newer and improved dyes and imaging techniques.

Epidemiological, therapeutic, and survival trends in malignant pleural mesothelioma: A review of the National Cancer Database.

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive cancer of the cells lining the pleural cavity with a low overall incidence. The National Cancer Database (NCDB) released in August 2022 updated data that reflect the newest trends in MPM. METHODS: The NCDB was queried for patients diagnosed with MPM between 2004 and 2020. Variables collected included demographics, tumor characteristics, and treatment. Student's t-test and independent-samples proportions test were used for means analysis. Survival was assessed by the Kaplan-Meier method using SPSS version 28. RESULTS: A total of 41,074 patients were diagnosed with mesothelioma, with a steady incidence (0.25%) between 2004 and 2017. The mean age of diagnosis was 70 (SD 13). 73.2% of the patients were males, 69% had no comorbidities, and 93.3% were white. More patients were diagnosed at Stage 1 after 2008 (p < 0.001). Since 2010, there has been a significant increase in patients offered treatment with 73.9% receiving some therapy (p < 0.01): 50.5% received chemotherapy, 27.6% surgery, 8.6% radiation, and 5.4% immunotherapy. The median overall survival was 10.3 months from diagnosis [95% CI: 10.2-10.5]. Risk factors associated with 30-day mortality from surgical intervention included age (OR = 1.02, p < 0.001), male gender (OR = 1.3, p = 0.03), poorly differentiated grade (OR = 2.1, p < 0.001), Stage 4 (OR = 1.4, p = 0014), and epithelioid histology (OR = 0.51, p = 0.03). CONCLUSION: The current management of MPM is based on stage and histologic subtype. Due to the small numbers of patients at most academic centers, the NCDB provides a robust dataset to draw upon broad data points in treatment discussions with patients.

Single-institution experience of 500 pulmonary resections guided by intraoperative molecular imaging.

OBJECTIVE: Intraoperative molecular imaging (IMI) using tumor-targeted optical contrast agents can improve thoracic cancer resections. There are no large-scale studies to guide surgeons in patient selection or imaging agent choice. Here, we report our institutional experience with IMI for lung and pleural tumor resection in 500 patients over a decade. METHODS: Between December 2011 and November 2021, patients with lung or pleural nodules undergoing resection were preoperatively infused with 1 of 4 optical contrast tracers: EC17, TumorGlow, pafolacianine, or SGM-101. Then, during resection, IMI was used to identify pulmonary nodules, confirm margins, and identify synchronous lesions. We retrospectively reviewed patient demographic data, lesion diagnoses, and IMI tumor-to-background ratios (TBRs). RESULTS: Five hundred patients underwent resection of 677 lesions. We found that there were 4 types of clinical utility of IMI: detection of positive margins (n = 32, 6.4% of patients), identification of residual disease after resection (n = 37, 7.4%), detection of synchronous cancers not predicted on preoperative imaging (n = 26, 5.2%), and minimally invasive localization of nonpalpable lesions (n = 101 lesions, 14.9%). Pafolacianine was most effective for adenocarcinoma-spectrum malignancies (mean TBR, 2.84), and TumorGlow was most effective for metastatic disease and mesothelioma (TBR, 3.1). False-negative fluorescence was primarily seen in mucinous adenocarcinomas (mean TBR, 1.8), heavy smokers (>30 pack years; TBR, 1.9), and tumors greater than 2.0 cm from the pleural surface (TBR, 1.3). CONCLUSIONS: IMI may be effective in improving resection of lung and pleural tumors. The choice of IMI tracer should vary by the surgical indication and the primary clinical challenge.

Prospective validation of tumor folate receptor expression density with the association of pafolacianine fluorescence during intraoperative molecular imaging-guided lung cancer resections.

PURPOSE: Pafolacianine, a folate receptor alpha-targeted NIR tracer, has demonstrated clear efficacy in intraoperative molecular imaging-guided (IMI) lung cancer surgery. However, the selection of patients who would benefit from IMI remains challenging given the variability of fluorescence with patient-associated and histopathologic factors. Our goal in this study was to prospectively evaluate whether preoperative FRα/FRß staining can predict pafolacianine-based fluorescence during real-time lung cancer resections. METHODS: This was a prospective study conducted between 2018 and 2022 that reviewed core biopsy and intraoperative data from patients with suspected lung cancer. A total of 196 patients were deemed eligible, of whom core biopsies were taken from 38 patients and assessed for FRα and FRß expression by immunohistochemistry (IHC). All patients underwent infusion of pafolacianine 24 h prior to surgery. Intraoperative fluorescence images were captured with the VisionSense bandpass filter-enabled camera. All histopathologic assessments were performed by a board-certified thoracic pathologist. RESULTS: Of the 38 patients, 5 (13.1%) were found to have benign lesions (necrotizing granulomatous inflammation, lymphoid aggregates) and 1 had metastatic non-lung nodule. Thirty (81.5%) had malignant lesions, with the vast majority (23, 77.4%) being lung adenocarcinoma (7 (22.5%) SCC). None of the benign tumors (0/5, 0%) exhibited in vivo fluorescence (mean TBR of 1.72), while 95% of the malignant tumors fluoresced (mean TBR of 3.11 ± 0.31) compared to squamous cell carcinoma (1.89 ± 0.29) of the lung and sarcomatous lung metastasis (2.32 ± 0.09) (p < 0.01). The TBR was significantly higher in the malignant tumors (p = 0.009). The median FRα and FRß staining intensities were both 1.5 for benign tumors, while the FRα and FRß staining intensities were 3 and 2 for malignant tumors, respectively. Increased FRα expression was significantly associated with the presence of fluorescence (p = 0.01), CONCLUSION: This prospective study sought to determine whether preoperative FRα and FRß expression on core biopsy IHC correlates with intraoperative fluorescence during pafolacianine-guided surgery. These results, although of small sample size, including limited non-adenocarcinoma cohort, suggest that performing FRα IHC on preoperative core biopsies of adenocarcinomas as compared to squamous cell carcinomas could provide low-cost, clinically useful information for optimal patient selection which should be further explored in advanced clinical trials.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule Type 5 Receptor-Targeted Fluorescent Intraoperative Molecular Imaging Tracer for Lung Cancer: A Nonrandomized Controlled Trial.

Importance: Localization of subcentimeter ground glass opacities during minimally invasive thoracoscopic lung cancer resections is a significant challenge in thoracic oncology. Intraoperative molecular imaging has emerged as a potential solution, but the availability of suitable fluorescence agents is a limiting factor. Objective: To evaluate the suitability of SGM-101, a carcinoembryonic antigen-related cell adhesion molecule type 5 (CEACAM5) receptor-targeted near-infrared fluorochrome, for molecular imaging-guided lung cancer resections, because glycoprotein is expressed in more than 80% of adenocarcinomas. Design, Setting, and Participants: For this nonrandomized, proof-of-principal, phase 1 controlled trial, patients were divided into 2 groups between August 1, 2020, and January 31, 2022. Patients with known CEACAM5-positive gastrointestinal tumors suggestive of lung metastasis were selected as proof-of-principle positive controls. The investigative group included patients with lung nodules suggestive of primary lung malignant neoplasms. Patients 18 years or older without significant comorbidities that precluded surgical exploration with suspicious pulmonary nodules requiring surgical biopsy were included in the study. Interventions: SGM-101 (10 mg) was infused up to 5 days before index operation, and pulmonary nodules were imaged using a near-infrared camera system with a dedicated thoracoscope. Main Outcomes and Measures: SGM-101 localization to pulmonary nodules and its correlation with CEACAM5 glycoprotein expression by the tumor as quantified by tumor and normal pulmonary parenchymal fluorescence. Results: Ten patients (5 per group; 5 male and 5 female; median [IQR] age, 66 [58-69] years) with 14 total lesions (median [range] lesion size, 0.91 [0.90-2.00] cm) were enrolled in the study. In the control group of 4 patients (1 patient did not undergo surgical resection because of abnormal preoperative cardiac clearance findings that were not deemed related to SGM-101 infusion), the mean (SD) lesion size was 1.33 (0.48) cm, 2 patients had elevated serum CEA markers, and 2 patients had normal serum CEA levels. Of the 4 patients who underwent surgical intervention, those with 2+ and 3+ tissue CEACAM5 expression had excellent tumor fluorescence, with a mean (SD) tumor to background ratio of 3.11 (0.45). In the patient cohort, the mean (SD) lesion size was 0.68 (0.22) cm, and no elevations in serum CEA levels were found. Lack of SGM-101 fluorescence was associated with benign lesions and with lack of CEACAM5 staining. Conclusions and Relevance: This in-human proof-of-principle nonrandomized controlled trial demonstrated SGM-101 localization to CEACAM5-positive tumors with the detection of real-time near-infrared fluorescence in situ, ex vivo, and by immunofluorescence microscopy. These findings suggest that SGM-101 is a safe, receptor-specific, and feasible intraoperative molecular imaging fluorochrome that should be further evaluated in randomized clinical trials. Trial Registration: ClinicalTrials.gov identifier: NCT04315467.

Sodium Multivitamin Transporter-Targeted Fluorochrome Facilitates Enhanced Metabolic Evaluation of Tumors Through Coenzyme-R Dependent Intracellular Signaling Pathways.

BACKGROUND: Intraoperative molecular imaging (IMI)-guided resections have been shown to improve oncologic outcomes for patients undergoing surgery for solid malignancies. The technology utilizes fluorescent tracers targeting cancer cells without the use of any ionizing radiation. However, currently available targeted IMI tracers are effective only for tumors with a highly specific receptor expression profile, and there is an unmet need for IMI tracers to label a broader range of tumor types. Here, we describe the development and testing of a novel tracer (CR)-S0456) targeted to the sodium multivitamin transporter (SMVT). METHODS: Preclinical models of fibrosarcoma (HT-1080), lung (A549), breast (4T1), and renal cancers (HEK-293 T) in vitro and in vivo were used for assessment of (CR)-S0456 specific tumor labeling via sodium-mediated SMVT uptake in dipotassium phosphate or choline chloride-containing media buffer. Additionally, pharmacologic inhibition of multiple intracellular coenzyme-R obligate signaling pathways, including holocarboxylase synthetase (sulconazole nitrate), PI3K/AKT/mTOR (omipalisib), and calmodulin-dependent phosphatase (calmidazolium), were investigated to assess (CR)-S0456 uptake kinetics. Human fibrosarcoma-bearing xenografts in athymic nude mice were used for tumor and metabolic-specific labeling. Novel NIR needle confocal laser endomicroscopic (nCLE) intratumoral sampling was performed to demonstrate single-cell specific labeling by CR-S0456. RESULTS: CR-S0456 localization in vitro correlated with highly proliferative cell lines (MTT) and doubling time (p < 0.05) with the highest microscopic fluorescence detected in aggressive human fibrosarcomas (HT-1080). Coenzyme-R-specific localization was demonstrated to be SMVT-specific after competitive inhibition of internal localization with excess administration of pantothenic acid. Inhibiting the activity of SMVT by affecting sodium ion hemostasis prevented the complete uptake of CR-S0456. In vivo validation demonstrated (CR)-S0456 localization to xenograft models with accurate identification of primary tumors as well as margin assessment down to 1 mm3 tumor volume. Systemic treatment of xenograft-bearing mice with a dual PI3K/mTOR inhibitor suppressed intratumoral cell signaling and (CR)-S0456 uptake via a reduction in SMVT expression. Novel analysis of in vivo intratumoral cytologic fluorescence using near-infrared confocal laser endomicroscopy demonstrated the absence of coenzyme-R-mediated NIR fluorescence but not fibroblast activation protein (FAP)-conjugated fluorochrome, indicating specific intracellular inhibition of coenzyme-R obligate pathways. CONCLUSION: These findings suggest that a SMVT-targeted NIR contrast agent can be a suitable tracer for imaging a wide range of malignancies as well as evaluating metabolic response to systemic therapies, similar to PET imaging with immune checkpoint inhibitors.

Three-Dimensional Near-Infrared Specimen Mapping Can Identify the Distance from the Tumor to the Surgical Margin During Resection of Pulmonary Ground Glass Opacities.

BACKGROUND: Lung cancers can recur locally due to inadequate resection margins. Achieving adequate margin distances is challenging in pulmonary ground glass opacities (GGOs) because they are not easily palpable. To improve margin assessment during resection of GGOs, we propose a novel technique, three-dimensional near-infrared specimen mapping (3D-NSM). METHODS: Twenty patients with a cT1 GGO were enrolled and received a fluorescent tracer preoperatively. After resection, specimens underwent 3D-NSM in the operating room. Margins were graded as positive or negative based upon fluorescence at the staple line. Images were analyzed using ImageJ to quantify the distance from the tumor edge to the nearest staple line. This margin distance calculated by 3D-NSM was compared to the margin distance reported on final pathology several days postoperatively. RESULTS: 3D-NSM identified 20/20 GGOs with no false positive or false negative diagnoses. Mean fluorescence intensity for lesions was 110.92 arbitrary units (A.U.) (IQR: 77.77-122.03 A.U.) compared to 23.68 A.U. (IQR: 19.60-27.06 A.U.) for background lung parenchyma (p < 0.0001). There were 4 tumor-positive or close margins in the study cohort, and all 4 (100%) were identified by 3D-NSM. 3D-NSM margin distances were nearly identical to margin distances reported on final pathology (R2 = 0.9362). 3D-NSM slightly under-predicted margin distance, and the median difference in margins was 1.9 mm (IQR 0.5-4.3 mm). CONCLUSIONS: 3D-NSM rapidly localizes GGOs by fluorescence and detects tumor-positive or close surgical margins. 3D-NSM can accurately quantify the resection margin distance as compared to formal pathology, which allows surgeons to rapidly determine whether sublobar resection margin distances are adequate.

Effects of Light-absorbing Carbons in Intraoperative Molecular Imaging-Guided Lung Cancer Resections.

BACKGROUND: One of the novel advancements to enhance the visual aspects of lung cancer identification is intraoperative molecular imaging (IMI), which can reliably detect tumors that would otherwise be missed by standard techniques such as tactile and visual feedback, particularly for sub-centimeter or ground-glass nodules. However, there remains a subset of patients who do not benefit from IMI due to excessive background fluorescence secondary to parenchymal light-absorbing carbon deposition. Our goal was to identify the effects of these carbonaceous materials on the quality of IMI-guided lung cancer resections. STUDY DESIGN AND METHODS: Between July 2014 and May 2021, a total of 311 patients were included in the study. Patients underwent infusion of the study drug OTL38 or ICG up to 24 h prior to VATS for lung cancer. Several factors such as age, tumor subtype, PET SUV, smoking, demographics, chronic lung conditions, patient domicile, and anthracosis were analyzed with respect to lung fluorescence during IMI. P values < 0.05 were considered statistically significant. RESULTS: Variables such as age, sex, and race had no statistical correlation to IMI success. However, smoking status and pack year had a statistically significant correlation with background parenchymal fluorescence and lung inflammation (p < 0.05). MFI of background (lung parenchyma) correlated with smoking history (p < 0.05) which led to decreased tumor-to-background ratio (TBR) measurements for all patients with proven malignancy (p < 0.05). Patients with chronic lung disease appear to have increased background parenchymal fluorescence regardless of smoking history (287 vs. 154, p < 0.01). City dwellers compared to other groups appear to be exposed to higher pollutant load and have higher rates of anthracosis, but living location's impact on fluorescence quantification appears to be not statistically significant. CONCLUSION: Smokers with greater than 10 PPY and those with chronic lung disease appear to have decreased lesion-to-background discrimination, significant anthracosis, and reduced IMI efficacy secondary to light-absorbing carbon deposition.

Evaluation of OTL38-Generated Tumor-to-Background Ratio in Intraoperative Molecular Imaging-Guided Lung Cancer Resections.

INTRODUCTION: Cancer surgery has multiple challenges including localizing small lesions, ensuring negative margins, and identifying synchronous cancers. One of the tools proposed to address these issues is intraoperative molecular imaging (IMI). An important consideration in IMI is the quantification of the tumor fluorescence during the procedure and using that data to add clinical value. Currently, the most commonly cited measure of quantification is the tumor-to-background ratio (TBR). Our goal was to evaluate the clinical value of TBR measured with OTL38 NIR tracer during a lung cancer resection. METHODS: Intraoperative data was retrospectively reviewed from a prospectively collected 5-year database. Between 2015 and 2020, 279 patients were included in the study. For standardization, all patients underwent infusion of the same targeted molecular optical contrast agent (OTL38) for lung cancer resections; then, the mean fluorescence intensity of the tumors and background tissues were calculated. To evaluate the clinical efficacy of the TBR calculation, the results were correlated with patient, biologic, tumor, and technological factors. RESULTS: For pulmonary surgery, patient factors such as gender, age, smoking history, and time from infusion of OTL38 to surgery did not have any statistical significance in predicting the TBR during surgery. In addition, TBR measurements did not correlate with location of the tumor in the lung (p = 0.123). There was no statistical correlation of preoperative positron emission tomography measurements (standardized uptake value) with intraoperative TBR. However, there was statistically significant negative correlation of in situ TBR measurement and the distance of the lesion from the surface of the organ (p < 0.001). Adenocarcinoma spectrum lesions overall had statistically significant correlation with in situ fluorescence compared to other NSCLC malignancies (p < 0.01) but TBR measurements could not identify histopathologic subtype on univariate analysis (p = 0.089). There was a tendency for in situ fluorescence for moderately and well-differentiated adenocarcinoma spectrum lesions, but this was not statistically significant. When comparing the in situ TBR of benign to malignant nodules in the lung, there was no statistically significant association (p = 0.145). In subset analysis, adenocarcinoma spectrum lesions tend to fluoresce at brighter with OTL38 compared to other histologic subtypes. CONCLUSION: In our various iterations, the results of our retrospective analysis did not show that TBR measurements during OTL38-guided surgery provide clinically useful information about the nature of the nodule or cancer. The true value of IMI is in the ability for the surgeon to use the fluorescence to guide the surgeon to the tumor and margins, but that sophisticated quantification of the amount of fluorescence may not have clinical utility.

Glycoprotein Receptor CEACAM5-Targeted Intraoperative Molecular Imaging Tracer in Non-Small Cell Lung Cancer.

BACKGROUND: Intraoperative molecular imaging has emerged as a potential tool in addressing challenges faced during lung cancer surgery by localizing small lesions, ensuring negative margins, and identifying synchronous cancers. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) glycoprotein has emerged as a potential target in fluorescent labeling of non-small cell lung cancer given the high antigen density in tumor cells and absence of expression in normal parenchyma. The goal of our study was to determine whether anti-CEACAM5 targeted near-infrared fluorochrome could be a suitable target in non-small cell lung cancer. METHODS: The CEACAM5 expression was evaluated in AB-12 (known negative control), HT29 (known positive control), and H460 (non-small cell lung cancer) cell lines by polymerase chain reaction. SGM-101, a CEACAM5 antibody, coupled with a BM-104 near-infrared fluorescent tracer was evaluated with dose escalation, in vitro cellular localization, and immunofluorescence microscopy. Subsequently, in vivo validation was performed in 52 athymic nude xenografts. RESULTS: Polymerase chain reaction analysis demonstrated 3000x relative expression of CEACAM5 in HT-29 cells compared with AB-12. The H460 cells showed 1000x relative expression compared with AB12 (P < .05). Both HT29 and H460 cells showed tracer internalization with signal to background ratio of 4.5 (SD 0.34) whereas there was minimal uptake by AB12 cells with signal to background ratio 1.1 (SD 0.1; P < .05). There was linear fluorescence increase with increasing tracer dosing in receptor expressing cell lines. In preclinical models, HT-29 and H460 cells lines produced near-infrared fluorescence with average tumor to background ratio of 3.89 (SD 0.25) irrespective of tumor size compared with no fluorescence by AB12 tumors (P < .05). The CEACAM5 expressing tumors had excellent dye uptake compared with AB12 tumors. CONCLUSIONS: CEACAM5 serves as a possible receptor for targeted intraoperative molecular imaging resections in lung cancer. This study sets a path for evaluation of CEACAM5 targets in future clinical trials.

Cathepsin detection to identify malignant cells during robotic pulmonary resection.

Background: Intraoperative molecular imaging (IMI) uses a fluorescent probe to identify occult cancers. VGT-309 is a quenched activity-based probe that is activated in the presence of cathepsins, enzymes overexpressed in cancer cells, and detected by near-infrared (NIR) light. This study aims to evaluate the sensitivity and the positive predictive value (PPV) of robotic-assisted thoracic surgery (RATS) with intraoperative molecular imaging (RIMI) using VGT-309 to localize tumors using NIR light to detect areas with increased cathepsin activity. Our secondary outcome was to compare RIMI to video-assisted thoracic surgery (VATS) with intraoperative molecular imaging (VIMI). Methods: In a phase 2 clinical trial at the University of Pennsylvania, patients (n=10) with suspicious pulmonary lesions underwent RATS. First, white light was used followed by RIMI to identify tissues with increased cathepsin activity. Then, VIMI was performed to compare the sensitivity and PPV in identifying the cathepsin activity. The resected specimens were then evaluated for fluorescence and underwent histopathological analysis for cathepsin expression. Image analysis was performed using ImageJ software. Statistical analysis was conducted using IBM SPSS Statistics software. A P value of 0.05 or less was considered significant. Results: RATS with white light identified 6 out of the 10 pulmonary nodules, whereas adding RIMI identified an additional 4 more pulmonary nodules. RIMI and VIMI were able to detect the same 8/10 (80%) nodules. The addition of VIMI did not identify any lesions that RIMI may have missed. The mean fluorescence intensity of tumors visualized by RIMI was 115.81 A.U. [standard deviation (SD) =58.57] compared to 95.6 A.U. (SD =14.81) by VIMI (P=0.41). The mean tumor-to-background ratios (TBR) of tumors visualized by RIMI was 9.20 (SD =9.12) compared to 2.29 A.U. (SD =1.11) using VIMI (P=0.1). The sensitivity of RIMI and VIMI was 88.9% which was superior to that of RATS (55.6%). The PPV of RATS was 83.3% compared to 100% in RIMI and VIMI. Conclusions: RIMI is a valuable option for visualization of occult disease using VGT-309-guided IMI through identifying areas of increased cathepsin activity. In this small series, RIMI and VIMI showed clinical equivalence in sensitivity and PPV of detecting cathepsin activity.

Expert consensus on indocyanine green fluorescence imaging for thoracoscopic lung resection (The Version 2022).

The use of the white-light thoracoscopy is hampered by the low contrast between oncologic margins and surrounding normal parenchyma. As a result, many patients with in situ or micro-infiltrating adenocarcinoma have to undergo lobectomy due to a lack of tactile and visual feedback in the resection of solitary pulmonary nodules. Near-infrared (NIR) guided indocyanine green (ICG) fluorescence imaging technique has been widely investigated due to its unique capability in addressing the current challenges; however, there is no special consensus on the evidence and recommendations for its preoperative and intraoperative applications. This manuscript will describe the development process of a consensus on ICG fluorescence-guided thoracoscopic resection of pulmonary lesions and make recommendations that can be applied in a greater number of centers. Specifically, an expert panel of thoracic surgeons and radiographers was formed. Based on the quality of evidence and strength of recommendations, the consensus was developed in conjunction with the Chinese Guidelines on Video-assisted Thoracoscopy, and the National Comprehensive Cancer Network (NCCN) guidelines on the management of pulmonary lesions. Each of the statements was discussed and agreed upon with a unanimous consensus amongst the panel. A total of 6 consensus statements were developed. Fluorescence-guided thoracoscopy has unique advantages in the visualization of pulmonary nodules, and recognition and resection of the anterior plane of the pulmonary segment. The expert panel agrees that fluorescence-guided thoracoscopic surgery has the potential to become a routine operation for the treatment of pulmonary lesions.

Novel intraoperative near-infrared imaging strategy to identify abnormalities in the anterior mediastinum.

Thoracic surgeons are frequently asked to biopsy suspicious tissues in the anterior mediastinum to discriminate between a reactive versus malignant pathology such as lymph nodes. The most common benign cause of a mediastinal lymph node is a reactive lymph node from a prior infection or inflammatory process such as post-COVID or granulomatous disease. The most common malignant cause is a lymphoproliferative disorder but also metastatic disease from neck, breast and other regional cancers. Biopsies in this location are challenging because they are far from the trachea and the sternum is a barrier to most diagnostic procedures. Thus, a surgical biopsy is frequently required and a common procedure for Thoracic surgeons. Technically, identifying these lesions can be challenging, particularly for small lesions or those in patients with high body mass index. In order to improve contrast between diseased tissue in the anterior mediastinum and surrounding adipose tissue, we have been studying near-infrared imaging during surgery using indocyanine green (ICG) to give contrast to the abnormal tissues and to avoid an unnecessary extended resection. We developed a modified technique to give ICG to a patient during a biopsy in the anterior mediastinum to specifically highlight abnormal tissues. As a proof-of-principle, we present a case of a young woman with a suspicious 2 cm mediastinal lymph node that required surgical biopsy.